<?xml version="1.0" encoding="us-ascii"?>
<!-- Created by Merrill Corporation -->
<!-- Generated by Fujitsu Interstage XWand B0189 -->
<!--Generated by IRIS XBRL Generation Engine-->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xlink="http://www.w3.org/1999/xlink">
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureScheduleIIValuationAndQualifyingAccountsDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureScheduleIIValuationAndQualifyingAccountsDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureRelatedPartyTransactionsDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureRelatedPartyTransactionsDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureIncomeTaxesDetails3" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureIncomeTaxesDetails3" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureStockBasedCompensationDetails2" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureStockBasedCompensationDetails2" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureDebtDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureDebtDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails3" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureFairValueOfFinancialInstrumentsDetails3" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureAcquisitionsDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureAcquisitionsDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureGoodwillAndOtherIntangibleAssetsDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureGoodwillAndOtherIntangibleAssetsDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureDerivativeFinancialInstrumentsDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureDerivativeFinancialInstrumentsDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureSubsequentEventDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureSubsequentEventDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureStockBasedCompensationDetails3" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureStockBasedCompensationDetails3" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureStockBasedCompensationDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureStockBasedCompensationDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureStockBasedCompensationDetails4" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureStockBasedCompensationDetails4" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureSignificantAccountingPoliciesDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureSignificantAccountingPoliciesDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails6" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureFairValueOfFinancialInstrumentsDetails6" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureCashCashEquivalentsAndInvestmentsDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureCashCashEquivalentsAndInvestmentsDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails2" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureFairValueOfFinancialInstrumentsDetails2" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureAcquisitionDetails2" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureAcquisitionDetails2" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureRisksAndUncertaintiesDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureRisksAndUncertaintiesDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureIncomeTaxesDetails2" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureIncomeTaxesDetails2" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureStockholdersEquityDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureStockholdersEquityDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails4" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureFairValueOfFinancialInstrumentsDetails4" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails5" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureFairValueOfFinancialInstrumentsDetails5" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureCashCashEquivalentsAndInvestmentsDetails2" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureCashCashEquivalentsAndInvestmentsDetails2" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureFairValueOfFinancialInstrumentsDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureCommitmentsAndContingenciesDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureCommitmentsAndContingenciesDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureRisksAndUncertaintiesTables" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureRisksAndUncertaintiesTables" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureSegmentInformationDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureSegmentInformationDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureDerivativeFinancialInstrumentsDetails2" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureDerivativeFinancialInstrumentsDetails2" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureDerivativeFinancialInstrumentsDetails3" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureDerivativeFinancialInstrumentsDetails3" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureBalanceSheetDetailsDetails" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureBalanceSheetDetailsDetails" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureStockholdersEquityDetails2" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureStockholdersEquityDetails2" />
  <link:roleRef roleURI="http://www.silabs.com/role/DisclosureAcquisitionsTables" xlink:type="simple" xlink:href="slab-20131228.xsd#DisclosureAcquisitionsTables" />
  <link:roleRef roleURI="http://www.silabs.com/role/StatementOfStockholdersEquity" xlink:type="simple" xlink:href="slab-20131228.xsd#StatementOfStockholdersEquity" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" />
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureScheduleIIValuationAndQualifyingAccountsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAndQualifyingAccountsDisclosureLineItems" xlink:label="ValuationAndQualifyingAccountsDisclosureLineItems" xlink:title="ValuationAndQualifyingAccountsDisclosureLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAndQualifyingAccountsDisclosureTable" xlink:label="ValuationAndQualifyingAccountsDisclosureTable" xlink:title="ValuationAndQualifyingAccountsDisclosureTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="ValuationAndQualifyingAccountsDisclosureLineItems" xlink:to="ValuationAndQualifyingAccountsDisclosureTable" xlink:title="definition: ValuationAndQualifyingAccountsDisclosureLineItems to ValuationAndQualifyingAccountsDisclosureTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAllowancesAndReservesTypeAxis" xlink:label="ValuationAllowancesAndReservesTypeAxis" xlink:title="ValuationAllowancesAndReservesTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ValuationAndQualifyingAccountsDisclosureTable" xlink:to="ValuationAllowancesAndReservesTypeAxis" xlink:title="definition: ValuationAndQualifyingAccountsDisclosureTable to ValuationAllowancesAndReservesTypeAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAllowancesAndReservesDomain" xlink:label="ValuationAllowancesAndReservesDomain" xlink:title="ValuationAllowancesAndReservesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ValuationAllowancesAndReservesTypeAxis" xlink:to="ValuationAllowancesAndReservesDomain" xlink:title="definition: ValuationAllowancesAndReservesTypeAxis to ValuationAllowancesAndReservesDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAllowancesAndReservesDomain" xlink:label="ValuationAllowancesAndReservesDomain_2" xlink:title="ValuationAllowancesAndReservesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ValuationAllowancesAndReservesTypeAxis" xlink:to="ValuationAllowancesAndReservesDomain_2" xlink:title="definition: ValuationAllowancesAndReservesTypeAxis to ValuationAllowancesAndReservesDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAllowanceOfDeferredTaxAssetsMember" xlink:label="ValuationAllowanceOfDeferredTaxAssetsMember" xlink:title="ValuationAllowanceOfDeferredTaxAssetsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ValuationAllowancesAndReservesDomain" xlink:to="ValuationAllowanceOfDeferredTaxAssetsMember" xlink:title="definition: ValuationAllowancesAndReservesDomain to ValuationAllowanceOfDeferredTaxAssetsMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MovementInValuationAllowancesAndReservesRollForward" xlink:label="MovementInValuationAllowancesAndReservesRollForward" xlink:title="MovementInValuationAllowancesAndReservesRollForward" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ValuationAndQualifyingAccountsDisclosureLineItems" xlink:to="MovementInValuationAllowancesAndReservesRollForward" xlink:title="definition: ValuationAndQualifyingAccountsDisclosureLineItems to MovementInValuationAllowancesAndReservesRollForward" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAllowancesAndReservesBalance" xlink:label="ValuationAllowancesAndReservesBalance" xlink:title="ValuationAllowancesAndReservesBalance" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MovementInValuationAllowancesAndReservesRollForward" xlink:to="ValuationAllowancesAndReservesBalance" xlink:title="definition: MovementInValuationAllowancesAndReservesRollForward to ValuationAllowancesAndReservesBalance" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense" xlink:label="ValuationAllowancesAndReservesChargedToCostAndExpense" xlink:title="ValuationAllowancesAndReservesChargedToCostAndExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MovementInValuationAllowancesAndReservesRollForward" xlink:to="ValuationAllowancesAndReservesChargedToCostAndExpense" xlink:title="definition: MovementInValuationAllowancesAndReservesRollForward to ValuationAllowancesAndReservesChargedToCostAndExpense" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts" xlink:label="ValuationAllowancesAndReservesChargedToOtherAccounts" xlink:title="ValuationAllowancesAndReservesChargedToOtherAccounts" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MovementInValuationAllowancesAndReservesRollForward" xlink:to="ValuationAllowancesAndReservesChargedToOtherAccounts" xlink:title="definition: MovementInValuationAllowancesAndReservesRollForward to ValuationAllowancesAndReservesChargedToOtherAccounts" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationAllowancesAndReservesDeductions" xlink:label="ValuationAllowancesAndReservesDeductions" xlink:title="ValuationAllowancesAndReservesDeductions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MovementInValuationAllowancesAndReservesRollForward" xlink:to="ValuationAllowancesAndReservesDeductions" xlink:title="definition: MovementInValuationAllowancesAndReservesRollForward to ValuationAllowancesAndReservesDeductions" use="optional" order="4.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureRelatedPartyTransactionsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="RelatedPartyTransactionLineItems" xlink:title="RelatedPartyTransactionLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:title="ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="RelatedPartyTransactionLineItems" xlink:to="ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:title="definition: RelatedPartyTransactionLineItems to ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="RelatedPartyTransactionsByRelatedPartyAxis" xlink:title="RelatedPartyTransactionsByRelatedPartyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="RelatedPartyTransactionsByRelatedPartyAxis" xlink:title="definition: ScheduleOfRelatedPartyTransactionsByRelatedPartyTable to RelatedPartyTransactionsByRelatedPartyAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RelatedPartyDomain" xlink:label="RelatedPartyDomain" xlink:title="RelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="RelatedPartyDomain" xlink:title="definition: RelatedPartyTransactionsByRelatedPartyAxis to RelatedPartyDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RelatedPartyDomain" xlink:label="RelatedPartyDomain_2" xlink:title="RelatedPartyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="RelatedPartyDomain_2" xlink:title="definition: RelatedPartyTransactionsByRelatedPartyAxis to RelatedPartyDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PresidentMember" xlink:label="PresidentMember" xlink:title="PresidentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyDomain" xlink:to="PresidentMember" xlink:title="definition: RelatedPartyDomain to PresidentMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ExecutiveVicePresidentMember" xlink:label="ExecutiveVicePresidentMember" xlink:title="ExecutiveVicePresidentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyDomain" xlink:to="ExecutiveVicePresidentMember" xlink:title="definition: RelatedPartyDomain to ExecutiveVicePresidentMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DirectorMember" xlink:label="DirectorMember" xlink:title="DirectorMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyDomain" xlink:to="DirectorMember" xlink:title="definition: RelatedPartyDomain to DirectorMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfRelatedPartyTransactionsByRelatedPartyTable to BusinessAcquisitionAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EnergyMicroMember" xlink:label="EnergyMicroMember" xlink:title="EnergyMicroMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="EnergyMicroMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to EnergyMicroMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty" xlink:label="RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty" xlink:title="RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyTransactionLineItems" xlink:to="RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty" xlink:title="definition: RelatedPartyTransactionLineItems to RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BeneficialOwnershipPercentageInAcquiredEntity" xlink:label="BeneficialOwnershipPercentageInAcquiredEntity" xlink:title="BeneficialOwnershipPercentageInAcquiredEntity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyTransactionLineItems" xlink:to="BeneficialOwnershipPercentageInAcquiredEntity" xlink:title="definition: RelatedPartyTransactionLineItems to BeneficialOwnershipPercentageInAcquiredEntity" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessCombinationInitialConsiderationTransferred" xlink:label="BusinessCombinationInitialConsiderationTransferred" xlink:title="BusinessCombinationInitialConsiderationTransferred" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyTransactionLineItems" xlink:to="BusinessCombinationInitialConsiderationTransferred" xlink:title="definition: RelatedPartyTransactionLineItems to BusinessCombinationInitialConsiderationTransferred" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EscrowDeposit" xlink:label="EscrowDeposit" xlink:title="EscrowDeposit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyTransactionLineItems" xlink:to="EscrowDeposit" xlink:title="definition: RelatedPartyTransactionLineItems to EscrowDeposit" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:label="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:title="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyTransactionLineItems" xlink:to="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:title="definition: RelatedPartyTransactionLineItems to BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_RelatedPartyTransactionsInvestmentInAcquiredEntityByRelatedParty" xlink:label="RelatedPartyTransactionsInvestmentInAcquiredEntityByRelatedParty" xlink:title="RelatedPartyTransactionsInvestmentInAcquiredEntityByRelatedParty" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RelatedPartyTransactionLineItems" xlink:to="RelatedPartyTransactionsInvestmentInAcquiredEntityByRelatedParty" xlink:title="definition: RelatedPartyTransactionLineItems to RelatedPartyTransactionsInvestmentInAcquiredEntityByRelatedParty" use="optional" order="7.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureIncomeTaxesDetails3">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeTaxContingencyLineItems" xlink:label="IncomeTaxContingencyLineItems" xlink:title="IncomeTaxContingencyLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeTaxContingencyTable" xlink:label="IncomeTaxContingencyTable" xlink:title="IncomeTaxContingencyTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="IncomeTaxContingencyLineItems" xlink:to="IncomeTaxContingencyTable" xlink:title="definition: IncomeTaxContingencyLineItems to IncomeTaxContingencyTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="IncomeTaxContingencyTable" xlink:to="RangeAxis" xlink:title="definition: IncomeTaxContingencyTable to RangeAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense" xlink:label="UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense" xlink:title="UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeTaxContingencyLineItems" xlink:to="UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense" xlink:title="definition: IncomeTaxContingencyLineItems to UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued" xlink:label="UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued" xlink:title="UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeTaxContingencyLineItems" xlink:to="UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued" xlink:title="definition: IncomeTaxContingencyLineItems to UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued" use="optional" order="3.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureStockBasedCompensationDetails2">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:title="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="AwardTypeAxis" xlink:title="AwardTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="AwardTypeAxis" xlink:title="definition: ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable to AwardTypeAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:title="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="AwardTypeAxis" xlink:to="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:title="definition: AwardTypeAxis to ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="EmployeeStockOptionMember" xlink:title="EmployeeStockOptionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="EmployeeStockOptionMember" xlink:title="definition: ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain to EmployeeStockOptionMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_RestrictedStockAwardsAndRestrictedStockUnitsRSUMember" xlink:label="RestrictedStockAwardsAndRestrictedStockUnitsRSUMember" xlink:title="RestrictedStockAwardsAndRestrictedStockUnitsRSUMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="RestrictedStockAwardsAndRestrictedStockUnitsRSUMember" xlink:title="definition: ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain to RestrictedStockAwardsAndRestrictedStockUnitsRSUMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_RestrictedStockAwardsRestrictedStockUnitsRSUAndMarketStockUnitsMSUMember" xlink:label="RestrictedStockAwardsRestrictedStockUnitsRSUAndMarketStockUnitsMSUMember" xlink:title="RestrictedStockAwardsRestrictedStockUnitsRSUAndMarketStockUnitsMSUMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="RestrictedStockAwardsRestrictedStockUnitsRSUAndMarketStockUnitsMSUMember" xlink:title="definition: ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain to RestrictedStockAwardsRestrictedStockUnitsRSUAndMarketStockUnitsMSUMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:title="StockIssuedDuringPeriodSharesStockOptionsExercised" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:to="StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward to StockIssuedDuringPeriodSharesStockOptionsExercised" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:label="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:title="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" xlink:to="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract to ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageExercisePriceAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:label="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:title="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" xlink:to="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract to SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" xlink:label="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" xlink:title="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" xlink:to="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract to SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" xlink:label="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" xlink:title="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" xlink:to="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract to SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" use="optional" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:label="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:title="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:to="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract to SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" use="optional" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestNumber" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestNumber" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestNumber" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestNumber" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestNumber" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract" use="optional" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentOtherThanOptionsOutstandingWeightedAverageRemainingVestingTerm" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentOtherThanOptionsOutstandingWeightedAverageRemainingVestingTerm" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentOtherThanOptionsOutstandingWeightedAverageRemainingVestingTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentOtherThanOptionsOutstandingWeightedAverageRemainingVestingTerm" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentOtherThanOptionsOutstandingWeightedAverageRemainingVestingTerm" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestWeightedAverageRemainingVestingTerm" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestWeightedAverageRemainingVestingTerm" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestWeightedAverageRemainingVestingTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestWeightedAverageRemainingVestingTerm" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageRemainingVestingTermAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestWeightedAverageRemainingVestingTerm" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract" xlink:label="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract" xlink:title="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedAggregateIntrinsicValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedAggregateIntrinsicValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedAggregateIntrinsicValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedAggregateIntrinsicValue" xlink:title="definition: SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedAggregateIntrinsicValue" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestAggregateIntrinsicValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestAggregateIntrinsicValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestAggregateIntrinsicValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestAggregateIntrinsicValue" xlink:title="definition: SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingAndExpectedToVestAggregateIntrinsicValue" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateFairValueAbstract" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateFairValueAbstract" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateFairValueAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateFairValueAbstract" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateFairValueAbstract" use="optional" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateFairValueAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateFairValueAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract" use="optional" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalIntrinsicValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalIntrinsicValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalIntrinsicValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalIntrinsicValue" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalIntrinsicValue" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalGrantDateFairValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalGrantDateFairValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalGrantDateFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalGrantDateFairValue" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardStockBasedPaymentAndStockOptionValuesAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalGrantDateFairValue" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:label="EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:title="EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" use="optional" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:title="EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" use="optional" order="14.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions" xlink:label="ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions" xlink:title="ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions" use="optional" order="15.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureDebtDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="DebtInstrumentLineItems" xlink:title="DebtInstrumentLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="DebtInstrumentTable" xlink:title="DebtInstrumentTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentTable" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="CreditFacilityAxis" xlink:title="CreditFacilityAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="CreditFacilityAxis" xlink:title="definition: DebtInstrumentTable to CreditFacilityAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="CreditFacilityDomain" xlink:title="CreditFacilityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="CreditFacilityAxis" xlink:to="CreditFacilityDomain" xlink:title="definition: CreditFacilityAxis to CreditFacilityDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="CreditFacilityDomain_2" xlink:title="CreditFacilityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="CreditFacilityAxis" xlink:to="CreditFacilityDomain_2" xlink:title="definition: CreditFacilityAxis to CreditFacilityDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LineOfCreditMember" xlink:label="LineOfCreditMember" xlink:title="LineOfCreditMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditFacilityDomain" xlink:to="LineOfCreditMember" xlink:title="definition: CreditFacilityDomain to LineOfCreditMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="RevolvingCreditFacilityMember" xlink:title="RevolvingCreditFacilityMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditFacilityDomain" xlink:to="RevolvingCreditFacilityMember" xlink:title="definition: CreditFacilityDomain to RevolvingCreditFacilityMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_TermLoanFacilityAndRevolvingCreditFacilityOtherThanSwinglineLoansMember" xlink:label="TermLoanFacilityAndRevolvingCreditFacilityOtherThanSwinglineLoansMember" xlink:title="TermLoanFacilityAndRevolvingCreditFacilityOtherThanSwinglineLoansMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditFacilityDomain" xlink:to="TermLoanFacilityAndRevolvingCreditFacilityOtherThanSwinglineLoansMember" xlink:title="definition: CreditFacilityDomain to TermLoanFacilityAndRevolvingCreditFacilityOtherThanSwinglineLoansMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_TermLoanFacilityRevolvingCreditFacilitySwinglineAndOtherLoansMember" xlink:label="TermLoanFacilityRevolvingCreditFacilitySwinglineAndOtherLoansMember" xlink:title="TermLoanFacilityRevolvingCreditFacilitySwinglineAndOtherLoansMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="CreditFacilityDomain" xlink:to="TermLoanFacilityRevolvingCreditFacilitySwinglineAndOtherLoansMember" xlink:title="definition: CreditFacilityDomain to TermLoanFacilityRevolvingCreditFacilitySwinglineAndOtherLoansMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="LongtermDebtTypeAxis" xlink:title="LongtermDebtTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="LongtermDebtTypeAxis" xlink:title="definition: DebtInstrumentTable to LongtermDebtTypeAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="LongtermDebtTypeDomain" xlink:title="LongtermDebtTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="LongtermDebtTypeAxis" xlink:to="LongtermDebtTypeDomain" xlink:title="definition: LongtermDebtTypeAxis to LongtermDebtTypeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="LongtermDebtTypeDomain_2" xlink:title="LongtermDebtTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="LongtermDebtTypeAxis" xlink:to="LongtermDebtTypeDomain_2" xlink:title="definition: LongtermDebtTypeAxis to LongtermDebtTypeDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LoansPayableMember" xlink:label="LoansPayableMember" xlink:title="LoansPayableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongtermDebtTypeDomain" xlink:to="LoansPayableMember" xlink:title="definition: LongtermDebtTypeDomain to LoansPayableMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_VariableRateAxis" xlink:label="VariableRateAxis" xlink:title="VariableRateAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="VariableRateAxis" xlink:title="definition: DebtInstrumentTable to VariableRateAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="VariableRateDomain" xlink:title="VariableRateDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="VariableRateAxis" xlink:to="VariableRateDomain" xlink:title="definition: VariableRateAxis to VariableRateDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="VariableRateDomain_2" xlink:title="VariableRateDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="VariableRateAxis" xlink:to="VariableRateDomain_2" xlink:title="definition: VariableRateAxis to VariableRateDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LondonInterbankOfferedRateLIBORMember" xlink:label="LondonInterbankOfferedRateLIBORMember" xlink:title="LondonInterbankOfferedRateLIBORMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="VariableRateDomain" xlink:to="LondonInterbankOfferedRateLIBORMember" xlink:title="definition: VariableRateDomain to LondonInterbankOfferedRateLIBORMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PrimeRateMember" xlink:label="PrimeRateMember" xlink:title="PrimeRateMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="VariableRateDomain" xlink:to="PrimeRateMember" xlink:title="definition: VariableRateDomain to PrimeRateMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_DebtInstrumentVariableRateBaseFederalFundsMember" xlink:label="DebtInstrumentVariableRateBaseFederalFundsMember" xlink:title="DebtInstrumentVariableRateBaseFederalFundsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="VariableRateDomain" xlink:to="DebtInstrumentVariableRateBaseFederalFundsMember" xlink:title="definition: VariableRateDomain to DebtInstrumentVariableRateBaseFederalFundsMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_DebtInstrumentVariableRateBaseOneMonthLIBORMember" xlink:label="DebtInstrumentVariableRateBaseOneMonthLIBORMember" xlink:title="DebtInstrumentVariableRateBaseOneMonthLIBORMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="VariableRateDomain" xlink:to="DebtInstrumentVariableRateBaseOneMonthLIBORMember" xlink:title="definition: VariableRateDomain to DebtInstrumentVariableRateBaseOneMonthLIBORMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_DebtInstrumentVariableRateBaseBaseRateMember" xlink:label="DebtInstrumentVariableRateBaseBaseRateMember" xlink:title="DebtInstrumentVariableRateBaseBaseRateMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="VariableRateDomain" xlink:to="DebtInstrumentVariableRateBaseBaseRateMember" xlink:title="definition: VariableRateDomain to DebtInstrumentVariableRateBaseBaseRateMember" use="optional" order="5.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DebtInstrumentTable" xlink:to="RangeAxis" xlink:title="definition: DebtInstrumentTable to RangeAxis" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="LineOfCreditFacilityMaximumBorrowingCapacity" xlink:title="LineOfCreditFacilityMaximumBorrowingCapacity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityMaximumBorrowingCapacity" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityMaximumBorrowingCapacity" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="DebtInstrumentTerm" xlink:title="DebtInstrumentTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentTerm" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentTerm" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LineOfCreditFacilityPercentageAmortizationOfPrincipalInEachOfFirstTwoYears" xlink:label="LineOfCreditFacilityPercentageAmortizationOfPrincipalInEachOfFirstTwoYears" xlink:title="LineOfCreditFacilityPercentageAmortizationOfPrincipalInEachOfFirstTwoYears" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityPercentageAmortizationOfPrincipalInEachOfFirstTwoYears" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityPercentageAmortizationOfPrincipalInEachOfFirstTwoYears" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LineOfCreditFacilityNumberOfYearsWithFivePercentPrincipalAmortization" xlink:label="LineOfCreditFacilityNumberOfYearsWithFivePercentPrincipalAmortization" xlink:title="LineOfCreditFacilityNumberOfYearsWithFivePercentPrincipalAmortization" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityNumberOfYearsWithFivePercentPrincipalAmortization" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityNumberOfYearsWithFivePercentPrincipalAmortization" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LineOfCreditFacilityPercentageAmortizationOfPrincipalInYearsThreeThroughFive" xlink:label="LineOfCreditFacilityPercentageAmortizationOfPrincipalInYearsThreeThroughFive" xlink:title="LineOfCreditFacilityPercentageAmortizationOfPrincipalInYearsThreeThroughFive" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityPercentageAmortizationOfPrincipalInYearsThreeThroughFive" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityPercentageAmortizationOfPrincipalInYearsThreeThroughFive" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LineOfCreditFacilityNumberOfYearsWithTenPercentPrincipalAmortization" xlink:label="LineOfCreditFacilityNumberOfYearsWithTenPercentPrincipalAmortization" xlink:title="LineOfCreditFacilityNumberOfYearsWithTenPercentPrincipalAmortization" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityNumberOfYearsWithTenPercentPrincipalAmortization" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityNumberOfYearsWithTenPercentPrincipalAmortization" use="optional" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LettersOfCreditMaximumAmount" xlink:label="LettersOfCreditMaximumAmount" xlink:title="LettersOfCreditMaximumAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LettersOfCreditMaximumAmount" xlink:title="definition: DebtInstrumentLineItems to LettersOfCreditMaximumAmount" use="optional" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SwinglineLoanMaximumAmount" xlink:label="SwinglineLoanMaximumAmount" xlink:title="SwinglineLoanMaximumAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="SwinglineLoanMaximumAmount" xlink:title="definition: DebtInstrumentLineItems to SwinglineLoanMaximumAmount" use="optional" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LineOfCreditFacilityAdditionalCapacityIncreaseOption" xlink:label="LineOfCreditFacilityAdditionalCapacityIncreaseOption" xlink:title="LineOfCreditFacilityAdditionalCapacityIncreaseOption" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityAdditionalCapacityIncreaseOption" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityAdditionalCapacityIncreaseOption" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LineOfCreditFacilityAmountOutstanding" xlink:label="LineOfCreditFacilityAmountOutstanding" xlink:title="LineOfCreditFacilityAmountOutstanding" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityAmountOutstanding" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityAmountOutstanding" use="optional" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentDescriptionOfVariableRateBasis" xlink:label="DebtInstrumentDescriptionOfVariableRateBasis" xlink:title="DebtInstrumentDescriptionOfVariableRateBasis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentDescriptionOfVariableRateBasis" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentDescriptionOfVariableRateBasis" use="optional" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="DebtInstrumentBasisSpreadOnVariableRate1" xlink:title="DebtInstrumentBasisSpreadOnVariableRate1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentBasisSpreadOnVariableRate1" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentBasisSpreadOnVariableRate1" use="optional" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LineOfCreditFacilityMaximumLeverageRatio" xlink:label="LineOfCreditFacilityMaximumLeverageRatio" xlink:title="LineOfCreditFacilityMaximumLeverageRatio" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityMaximumLeverageRatio" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityMaximumLeverageRatio" use="optional" order="14.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LineOfCreditFacilityMinimumFixedChargeCoverageRatio" xlink:label="LineOfCreditFacilityMinimumFixedChargeCoverageRatio" xlink:title="LineOfCreditFacilityMinimumFixedChargeCoverageRatio" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityMinimumFixedChargeCoverageRatio" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityMinimumFixedChargeCoverageRatio" use="optional" order="15.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtPercentageBearingFixedInterestRate" xlink:label="LongTermDebtPercentageBearingFixedInterestRate" xlink:title="LongTermDebtPercentageBearingFixedInterestRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebtPercentageBearingFixedInterestRate" xlink:title="definition: DebtInstrumentLineItems to LongTermDebtPercentageBearingFixedInterestRate" use="optional" order="16.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:label="DebtInstrumentInterestRateEffectivePercentage" xlink:title="DebtInstrumentInterestRateEffectivePercentage" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentInterestRateEffectivePercentage" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentInterestRateEffectivePercentage" use="optional" order="17.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtByMaturityAbstract" xlink:label="LongTermDebtByMaturityAbstract" xlink:title="LongTermDebtByMaturityAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebtByMaturityAbstract" xlink:title="definition: DebtInstrumentLineItems to LongTermDebtByMaturityAbstract" use="optional" order="18.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:label="LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:title="LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongTermDebtByMaturityAbstract" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:title="definition: LongTermDebtByMaturityAbstract to LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:label="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:title="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongTermDebtByMaturityAbstract" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:title="definition: LongTermDebtByMaturityAbstract to LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:label="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:title="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongTermDebtByMaturityAbstract" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:title="definition: LongTermDebtByMaturityAbstract to LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:label="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:title="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongTermDebtByMaturityAbstract" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:title="definition: LongTermDebtByMaturityAbstract to LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebt" xlink:label="LongTermDebt" xlink:title="LongTermDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongTermDebtByMaturityAbstract" xlink:to="LongTermDebt" xlink:title="definition: LongTermDebtByMaturityAbstract to LongTermDebt" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:label="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:title="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongTermDebtByMaturityAbstract" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:title="definition: LongTermDebtByMaturityAbstract to LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear" xlink:label="LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear" xlink:title="LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongTermDebtByMaturityAbstract" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear" xlink:title="definition: LongTermDebtByMaturityAbstract to LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear" use="optional" order="8001.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails3">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:label="FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:title="FairValueInputsLiabilitiesQuantitativeInformationLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:label="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:title="FairValueInputsLiabilitiesQuantitativeInformationTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:to="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationLineItems to FairValueInputsLiabilitiesQuantitativeInformationTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByLiabilityClassAxis" xlink:label="FairValueByLiabilityClassAxis" xlink:title="FairValueByLiabilityClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:to="FairValueByLiabilityClassAxis" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationTable to FairValueByLiabilityClassAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:title="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByLiabilityClassAxis" xlink:to="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:title="definition: FairValueByLiabilityClassAxis to FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ContingentConsiderationMember" xlink:label="ContingentConsiderationMember" xlink:title="ContingentConsiderationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:to="ContingentConsiderationMember" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain to ContingentConsiderationMember" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:to="RangeAxis" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationTable to RangeAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationTechniqueAxis" xlink:label="ValuationTechniqueAxis" xlink:title="ValuationTechniqueAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:to="ValuationTechniqueAxis" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationTable to ValuationTechniqueAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationTechniqueDomain" xlink:label="ValuationTechniqueDomain" xlink:title="ValuationTechniqueDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ValuationTechniqueAxis" xlink:to="ValuationTechniqueDomain" xlink:title="definition: ValuationTechniqueAxis to ValuationTechniqueDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_MonteCarloSimulationMember" xlink:label="MonteCarloSimulationMember" xlink:title="MonteCarloSimulationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ValuationTechniqueDomain" xlink:to="MonteCarloSimulationMember" xlink:title="definition: ValuationTechniqueDomain to MonteCarloSimulationMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsLongTermRevenueGrowthRate" xlink:label="FairValueInputsLongTermRevenueGrowthRate" xlink:title="FairValueInputsLongTermRevenueGrowthRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:to="FairValueInputsLongTermRevenueGrowthRate" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationLineItems to FairValueInputsLongTermRevenueGrowthRate" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssumptionsExpectedVolatilityRate" xlink:label="FairValueAssumptionsExpectedVolatilityRate" xlink:title="FairValueAssumptionsExpectedVolatilityRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:to="FairValueAssumptionsExpectedVolatilityRate" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationLineItems to FairValueAssumptionsExpectedVolatilityRate" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssumptionsExpectedTerm" xlink:label="FairValueAssumptionsExpectedTerm" xlink:title="FairValueAssumptionsExpectedTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:to="FairValueAssumptionsExpectedTerm" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationLineItems to FairValueAssumptionsExpectedTerm" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsDiscountRate" xlink:label="FairValueInputsDiscountRate" xlink:title="FairValueInputsDiscountRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:to="FairValueInputsDiscountRate" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationLineItems to FairValueInputsDiscountRate" use="optional" order="5.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureAcquisitionsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EnergyMicroMember" xlink:label="EnergyMicroMember" xlink:title="EnergyMicroMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="EnergyMicroMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to EnergyMicroMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EmberCorporationMember" xlink:label="EmberCorporationMember" xlink:title="EmberCorporationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="EmberCorporationMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to EmberCorporationMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_HeadquartersLeasesMember" xlink:label="HeadquartersLeasesMember" xlink:title="HeadquartersLeasesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="HeadquartersLeasesMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to HeadquartersLeasesMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_WCesarChavez400Member" xlink:label="WCesarChavez400Member" xlink:title="WCesarChavez400Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="HeadquartersLeasesMember" xlink:to="WCesarChavez400Member" xlink:title="definition: HeadquartersLeasesMember to WCesarChavez400Member" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_WCesarChavez200Member" xlink:label="WCesarChavez200Member" xlink:title="WCesarChavez200Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="HeadquartersLeasesMember" xlink:to="WCesarChavez200Member" xlink:title="definition: HeadquartersLeasesMember to WCesarChavez200Member" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SpectraLinearIncMember" xlink:label="SpectraLinearIncMember" xlink:title="SpectraLinearIncMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="SpectraLinearIncMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to SpectraLinearIncMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="BusinessAcquisitionLineItems" xlink:title="BusinessAcquisitionLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="ScheduleOfBusinessAcquisitionsByAcquisitionTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="BusinessAcquisitionLineItems" xlink:to="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="definition: BusinessAcquisitionLineItems to ScheduleOfBusinessAcquisitionsByAcquisitionTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to BusinessAcquisitionAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="IndefiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to IndefiniteLivedIntangibleAssetsByMajorClassAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: IndefiniteLivedIntangibleAssetsByMajorClassAxis to IndefiniteLivedIntangibleAssetsMajorClassNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InProcessResearchAndDevelopmentMember" xlink:label="InProcessResearchAndDevelopmentMember" xlink:title="InProcessResearchAndDevelopmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="InProcessResearchAndDevelopmentMember" xlink:title="definition: IndefiniteLivedIntangibleAssetsMajorClassNameDomain to InProcessResearchAndDevelopmentMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="FiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to FiniteLivedIntangibleAssetsByMajorClassAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_TechnologyBasedIntangibleAssetsMember" xlink:label="TechnologyBasedIntangibleAssetsMember" xlink:title="TechnologyBasedIntangibleAssetsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="TechnologyBasedIntangibleAssetsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to TechnologyBasedIntangibleAssetsMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DevelopedTechnologyRightsMember" xlink:label="DevelopedTechnologyRightsMember" xlink:title="DevelopedTechnologyRightsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="DevelopedTechnologyRightsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to DevelopedTechnologyRightsMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CustomerRelationshipsMember" xlink:label="CustomerRelationshipsMember" xlink:title="CustomerRelationshipsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="CustomerRelationshipsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to CustomerRelationshipsMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_TrademarksMember" xlink:label="TrademarksMember" xlink:title="TrademarksMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="TrademarksMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to TrademarksMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferred1" xlink:label="BusinessCombinationConsiderationTransferred1" xlink:title="BusinessCombinationConsiderationTransferred1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationConsiderationTransferred1" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationConsiderationTransferred1" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationLiabilitiesArisingFromContingenciesAmountRecognized" xlink:label="BusinessCombinationLiabilitiesArisingFromContingenciesAmountRecognized" xlink:title="BusinessCombinationLiabilitiesArisingFromContingenciesAmountRecognized" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationLiabilitiesArisingFromContingenciesAmountRecognized" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationLiabilitiesArisingFromContingenciesAmountRecognized" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessCombinationInitialConsiderationTransferred" xlink:label="BusinessCombinationInitialConsiderationTransferred" xlink:title="BusinessCombinationInitialConsiderationTransferred" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationInitialConsiderationTransferred" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationInitialConsiderationTransferred" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred" xlink:label="BusinessCombinationConsiderationTransferredLiabilitiesIncurred" xlink:title="BusinessCombinationConsiderationTransferredLiabilitiesIncurred" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationConsiderationTransferredLiabilitiesIncurred" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationConsiderationTransferredLiabilitiesIncurred" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" xlink:label="BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" xlink:title="BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionSharesIssuableCreditorNoticePeriod" xlink:label="BusinessAcquisitionSharesIssuableCreditorNoticePeriod" xlink:title="BusinessAcquisitionSharesIssuableCreditorNoticePeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionSharesIssuableCreditorNoticePeriod" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionSharesIssuableCreditorNoticePeriod" use="optional" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability" xlink:label="BusinessCombinationContingentConsiderationLiability" xlink:title="BusinessCombinationContingentConsiderationLiability" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationContingentConsiderationLiability" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationContingentConsiderationLiability" use="optional" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:label="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:title="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" use="optional" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionPercentageOfMinimumAnnualRevenueGrowthRequiredForAdditionalConsiderationPayment" xlink:label="BusinessAcquisitionPercentageOfMinimumAnnualRevenueGrowthRequiredForAdditionalConsiderationPayment" xlink:title="BusinessAcquisitionPercentageOfMinimumAnnualRevenueGrowthRequiredForAdditionalConsiderationPayment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPercentageOfMinimumAnnualRevenueGrowthRequiredForAdditionalConsiderationPayment" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPercentageOfMinimumAnnualRevenueGrowthRequiredForAdditionalConsiderationPayment" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionEarnOutPeriod" xlink:label="BusinessAcquisitionEarnOutPeriod" xlink:title="BusinessAcquisitionEarnOutPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionEarnOutPeriod" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionEarnOutPeriod" use="optional" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessCombinationContingentConsiderationMaximumAnnualPayment" xlink:label="BusinessCombinationContingentConsiderationMaximumAnnualPayment" xlink:title="BusinessCombinationContingentConsiderationMaximumAnnualPayment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationContingentConsiderationMaximumAnnualPayment" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationContingentConsiderationMaximumAnnualPayment" use="optional" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessCombinationContingentConsiderationMinimumRevenueInFiscalYearFromEarnOutProductsRequiredForEntireEarnOutToBePayable" xlink:label="BusinessCombinationContingentConsiderationMinimumRevenueInFiscalYearFromEarnOutProductsRequiredForEntireEarnOutToBePayable" xlink:title="BusinessCombinationContingentConsiderationMinimumRevenueInFiscalYearFromEarnOutProductsRequiredForEntireEarnOutToBePayable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationContingentConsiderationMinimumRevenueInFiscalYearFromEarnOutProductsRequiredForEntireEarnOutToBePayable" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationContingentConsiderationMinimumRevenueInFiscalYearFromEarnOutProductsRequiredForEntireEarnOutToBePayable" use="optional" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EscrowDeposit" xlink:label="EscrowDeposit" xlink:title="EscrowDeposit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="EscrowDeposit" xlink:title="definition: BusinessAcquisitionLineItems to EscrowDeposit" use="optional" order="14.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessCombinationContingentConsiderationPercentageContingentOnContinuedEmploymentOfCertainKeyEmployees" xlink:label="BusinessCombinationContingentConsiderationPercentageContingentOnContinuedEmploymentOfCertainKeyEmployees" xlink:title="BusinessCombinationContingentConsiderationPercentageContingentOnContinuedEmploymentOfCertainKeyEmployees" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationContingentConsiderationPercentageContingentOnContinuedEmploymentOfCertainKeyEmployees" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationContingentConsiderationPercentageContingentOnContinuedEmploymentOfCertainKeyEmployees" use="optional" order="15.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionKeyEmployeesContinuedEmploymentPeriodForCalculatingPortionOfEarnOutFollowingAcquisitionDate" xlink:label="BusinessAcquisitionKeyEmployeesContinuedEmploymentPeriodForCalculatingPortionOfEarnOutFollowingAcquisitionDate" xlink:title="BusinessAcquisitionKeyEmployeesContinuedEmploymentPeriodForCalculatingPortionOfEarnOutFollowingAcquisitionDate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionKeyEmployeesContinuedEmploymentPeriodForCalculatingPortionOfEarnOutFollowingAcquisitionDate" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionKeyEmployeesContinuedEmploymentPeriodForCalculatingPortionOfEarnOutFollowingAcquisitionDate" use="optional" order="16.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionCostOfAcquiredLiabilitiesAssumedNet" xlink:label="BusinessAcquisitionCostOfAcquiredLiabilitiesAssumedNet" xlink:title="BusinessAcquisitionCostOfAcquiredLiabilitiesAssumedNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionCostOfAcquiredLiabilitiesAssumedNet" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionCostOfAcquiredLiabilitiesAssumedNet" use="optional" order="17.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionPostCombinationCostCompensationPaidToEmployeesOfAcquiredEntity" xlink:label="BusinessAcquisitionPostCombinationCostCompensationPaidToEmployeesOfAcquiredEntity" xlink:title="BusinessAcquisitionPostCombinationCostCompensationPaidToEmployeesOfAcquiredEntity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPostCombinationCostCompensationPaidToEmployeesOfAcquiredEntity" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPostCombinationCostCompensationPaidToEmployeesOfAcquiredEntity" use="optional" order="18.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" use="optional" order="19.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_Goodwill" xlink:label="Goodwill" xlink:title="Goodwill" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="Goodwill" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to Goodwill" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionPurchasePriceAllocationDeferredTaxAssetsNetNoncurrent" xlink:label="BusinessAcquisitionPurchasePriceAllocationDeferredTaxAssetsNetNoncurrent" xlink:title="BusinessAcquisitionPurchasePriceAllocationDeferredTaxAssetsNetNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessAcquisitionPurchasePriceAllocationDeferredTaxAssetsNetNoncurrent" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessAcquisitionPurchasePriceAllocationDeferredTaxAssetsNetNoncurrent" use="optional" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" use="optional" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNotesPayableCurrent" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNotesPayableCurrent" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNotesPayableCurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNotesPayableCurrent" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNotesPayableCurrent" use="optional" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" use="optional" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt" use="optional" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" use="optional" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilities" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilities" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilities" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilities" use="optional" order="14.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:title="definition: BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNetAbstract to BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" use="optional" order="15.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" xlink:label="BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" xlink:title="BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" use="optional" order="20.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:label="AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:title="AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:title="definition: BusinessAcquisitionLineItems to AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" use="optional" order="21.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_IndefiniteLivedIntangibleAssetsDiscountRateApplicableToCashFlows" xlink:label="IndefiniteLivedIntangibleAssetsDiscountRateApplicableToCashFlows" xlink:title="IndefiniteLivedIntangibleAssetsDiscountRateApplicableToCashFlows" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="IndefiniteLivedIntangibleAssetsDiscountRateApplicableToCashFlows" xlink:title="definition: BusinessAcquisitionLineItems to IndefiniteLivedIntangibleAssetsDiscountRateApplicableToCashFlows" use="optional" order="22.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_OperatingLeasesPurchasePriceForBuildings" xlink:label="OperatingLeasesPurchasePriceForBuildings" xlink:title="OperatingLeasesPurchasePriceForBuildings" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="OperatingLeasesPurchasePriceForBuildings" xlink:title="definition: BusinessAcquisitionLineItems to OperatingLeasesPurchasePriceForBuildings" use="optional" order="23.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildings" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildings" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildings" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildings" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildings" use="optional" order="24.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionPurchasePriceAllocationLeaseholdInterestInGroundLeases" xlink:label="BusinessAcquisitionPurchasePriceAllocationLeaseholdInterestInGroundLeases" xlink:title="BusinessAcquisitionPurchasePriceAllocationLeaseholdInterestInGroundLeases" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPurchasePriceAllocationLeaseholdInterestInGroundLeases" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPurchasePriceAllocationLeaseholdInterestInGroundLeases" use="optional" order="25.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionPurchasePriceAllocationAcquiredUnfavorableLeases" xlink:label="BusinessAcquisitionPurchasePriceAllocationAcquiredUnfavorableLeases" xlink:title="BusinessAcquisitionPurchasePriceAllocationAcquiredUnfavorableLeases" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPurchasePriceAllocationAcquiredUnfavorableLeases" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPurchasePriceAllocationAcquiredUnfavorableLeases" use="optional" order="26.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BusinessAcquisitionPurchasePriceAllocationLeaseRelatedCharges" xlink:label="BusinessAcquisitionPurchasePriceAllocationLeaseRelatedCharges" xlink:title="BusinessAcquisitionPurchasePriceAllocationLeaseRelatedCharges" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionPurchasePriceAllocationLeaseRelatedCharges" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionPurchasePriceAllocationLeaseRelatedCharges" use="optional" order="27.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationBargainPurchaseGainRecognizedAmount" xlink:label="BusinessCombinationBargainPurchaseGainRecognizedAmount" xlink:title="BusinessCombinationBargainPurchaseGainRecognizedAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationBargainPurchaseGainRecognizedAmount" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationBargainPurchaseGainRecognizedAmount" use="optional" order="28.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="PropertyPlantAndEquipmentUsefulLife" xlink:title="PropertyPlantAndEquipmentUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="PropertyPlantAndEquipmentUsefulLife" xlink:title="definition: BusinessAcquisitionLineItems to PropertyPlantAndEquipmentUsefulLife" use="optional" order="29.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LeaseholdInterestInGroundLeasesUsefulLife" xlink:label="LeaseholdInterestInGroundLeasesUsefulLife" xlink:title="LeaseholdInterestInGroundLeasesUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="LeaseholdInterestInGroundLeasesUsefulLife" xlink:title="definition: BusinessAcquisitionLineItems to LeaseholdInterestInGroundLeasesUsefulLife" use="optional" order="30.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_NumberOfLeasesPurchasePriceFixed" xlink:label="NumberOfLeasesPurchasePriceFixed" xlink:title="NumberOfLeasesPurchasePriceFixed" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="NumberOfLeasesPurchasePriceFixed" xlink:title="definition: BusinessAcquisitionLineItems to NumberOfLeasesPurchasePriceFixed" use="optional" order="31.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureGoodwillAndOtherIntangibleAssetsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="IndefiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: IndefiniteLivedIntangibleAssetsByMajorClassAxis to IndefiniteLivedIntangibleAssetsMajorClassNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InProcessResearchAndDevelopmentMember" xlink:label="InProcessResearchAndDevelopmentMember" xlink:title="InProcessResearchAndDevelopmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="InProcessResearchAndDevelopmentMember" xlink:title="definition: IndefiniteLivedIntangibleAssetsMajorClassNameDomain to InProcessResearchAndDevelopmentMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="FiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CustomerRelationshipsMember" xlink:label="CustomerRelationshipsMember" xlink:title="CustomerRelationshipsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="CustomerRelationshipsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to CustomerRelationshipsMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_TrademarksMember" xlink:label="TrademarksMember" xlink:title="TrademarksMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="TrademarksMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to TrademarksMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_CoreAndDevelopedTechnologyMember" xlink:label="CoreAndDevelopedTechnologyMember" xlink:title="CoreAndDevelopedTechnologyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="CoreAndDevelopedTechnologyMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to CoreAndDevelopedTechnologyMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PatentsMember" xlink:label="PatentsMember" xlink:title="PatentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="PatentsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to PatentsMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" xlink:label="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" xlink:title="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" xlink:label="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" xlink:title="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" xlink:to="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" xlink:title="definition: FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems to ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable to FiniteLivedIntangibleAssetsByMajorClassAxis" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable" xlink:to="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfFiniteLivedAndIndefiniteLivedIntangibleAssetsByMajorClassTable to IndefiniteLivedIntangibleAssetsByMajorClassAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:label="AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:title="AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" xlink:to="AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:title="definition: FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems to AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="FiniteLivedIntangibleAssetsGross" xlink:title="FiniteLivedIntangibleAssetsGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsGross" xlink:title="definition: FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsGross" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:title="FiniteLivedIntangibleAssetsAccumulatedAmortization" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:title="definition: FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAccumulatedAmortization" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill" xlink:label="IndefiniteLivedIntangibleAssetsExcludingGoodwill" xlink:title="IndefiniteLivedIntangibleAssetsExcludingGoodwill" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" xlink:to="IndefiniteLivedIntangibleAssetsExcludingGoodwill" xlink:title="definition: FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems to IndefiniteLivedIntangibleAssetsExcludingGoodwill" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill" xlink:label="IntangibleAssetsGrossExcludingGoodwill" xlink:title="IntangibleAssetsGrossExcludingGoodwill" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems" xlink:to="IntangibleAssetsGrossExcludingGoodwill" xlink:title="definition: FiniteLivedAndIndefiniteLivedIntangibleAssetsLineItems to IntangibleAssetsGrossExcludingGoodwill" use="optional" order="6.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureDerivativeFinancialInstrumentsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeLineItems" xlink:label="DerivativeLineItems" xlink:title="DerivativeLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeTable" xlink:label="DerivativeTable" xlink:title="DerivativeTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DerivativeLineItems" xlink:to="DerivativeTable" xlink:title="definition: DerivativeLineItems to DerivativeTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:label="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:title="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DerivativeTable" xlink:to="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:title="definition: DerivativeTable to DerivativeInstrumentsGainLossByHedgingRelationshipAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_HedgingRelationshipDomain" xlink:label="HedgingRelationshipDomain" xlink:title="HedgingRelationshipDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:to="HedgingRelationshipDomain" xlink:title="definition: DerivativeInstrumentsGainLossByHedgingRelationshipAxis to HedgingRelationshipDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CashFlowHedgingMember" xlink:label="CashFlowHedgingMember" xlink:title="CashFlowHedgingMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="HedgingRelationshipDomain" xlink:to="CashFlowHedgingMember" xlink:title="definition: HedgingRelationshipDomain to CashFlowHedgingMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="DerivativeInstrumentRiskAxis" xlink:title="DerivativeInstrumentRiskAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DerivativeTable" xlink:to="DerivativeInstrumentRiskAxis" xlink:title="definition: DerivativeTable to DerivativeInstrumentRiskAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="DerivativeContractTypeDomain" xlink:title="DerivativeContractTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="DerivativeInstrumentRiskAxis" xlink:to="DerivativeContractTypeDomain" xlink:title="definition: DerivativeInstrumentRiskAxis to DerivativeContractTypeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InterestRateSwapMember" xlink:label="InterestRateSwapMember" xlink:title="InterestRateSwapMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DerivativeContractTypeDomain" xlink:to="InterestRateSwapMember" xlink:title="definition: DerivativeContractTypeDomain to InterestRateSwapMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd#invest_DerivativeNotionalAmount" xlink:label="DerivativeNotionalAmount" xlink:title="DerivativeNotionalAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DerivativeLineItems" xlink:to="DerivativeNotionalAmount" xlink:title="definition: DerivativeLineItems to DerivativeNotionalAmount" use="optional" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureSubsequentEventDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EnergyMicroMember" xlink:label="EnergyMicroMember" xlink:title="EnergyMicroMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="EnergyMicroMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to EnergyMicroMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SubsequentEventLineItems" xlink:label="SubsequentEventLineItems" xlink:title="SubsequentEventLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SubsequentEventTable" xlink:label="SubsequentEventTable" xlink:title="SubsequentEventTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="SubsequentEventLineItems" xlink:to="SubsequentEventTable" xlink:title="definition: SubsequentEventLineItems to SubsequentEventTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="SubsequentEventTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: SubsequentEventTable to BusinessAcquisitionAxis" use="optional" order="1.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureStockBasedCompensationDetails3">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:title="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="IncomeStatementLocationAxis" xlink:title="IncomeStatementLocationAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="IncomeStatementLocationAxis" xlink:title="definition: ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable to IncomeStatementLocationAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="IncomeStatementLocationDomain" xlink:title="IncomeStatementLocationDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="IncomeStatementLocationAxis" xlink:to="IncomeStatementLocationDomain" xlink:title="definition: IncomeStatementLocationAxis to IncomeStatementLocationDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="CostOfSalesMember" xlink:title="CostOfSalesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeStatementLocationDomain" xlink:to="CostOfSalesMember" xlink:title="definition: IncomeStatementLocationDomain to CostOfSalesMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="ResearchAndDevelopmentExpenseMember" xlink:title="ResearchAndDevelopmentExpenseMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeStatementLocationDomain" xlink:to="ResearchAndDevelopmentExpenseMember" xlink:title="definition: IncomeStatementLocationDomain to ResearchAndDevelopmentExpenseMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SellingGeneralAndAdministrativeExpenseMember" xlink:label="SellingGeneralAndAdministrativeExpenseMember" xlink:title="SellingGeneralAndAdministrativeExpenseMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeStatementLocationDomain" xlink:to="SellingGeneralAndAdministrativeExpenseMember" xlink:title="definition: IncomeStatementLocationDomain to SellingGeneralAndAdministrativeExpenseMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="PlanNameAxis" xlink:title="PlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="PlanNameAxis" xlink:title="definition: ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable to PlanNameAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="PlanNameDomain" xlink:title="PlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="PlanNameAxis" xlink:to="PlanNameDomain" xlink:title="definition: PlanNameAxis to PlanNameDomain" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_StockIncentivePlan2009Member" xlink:label="StockIncentivePlan2009Member" xlink:title="StockIncentivePlan2009Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PlanNameDomain" xlink:to="StockIncentivePlan2009Member" xlink:title="definition: PlanNameDomain to StockIncentivePlan2009Member" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:label="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:title="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="AllocatedShareBasedCompensationExpense" xlink:title="AllocatedShareBasedCompensationExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="AllocatedShareBasedCompensationExpense" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to AllocatedShareBasedCompensationExpense" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense" xlink:label="EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense" xlink:title="EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpenseNetOfTax" xlink:label="AllocatedShareBasedCompensationExpenseNetOfTax" xlink:title="AllocatedShareBasedCompensationExpenseNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="AllocatedShareBasedCompensationExpenseNetOfTax" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to AllocatedShareBasedCompensationExpenseNetOfTax" use="optional" order="4.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureStockBasedCompensationDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="AwardTypeAxis" xlink:title="AwardTypeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:title="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="AwardTypeAxis" xlink:to="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:title="definition: AwardTypeAxis to ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_2" xlink:title="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="AwardTypeAxis" xlink:to="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_2" xlink:title="definition: AwardTypeAxis to ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="EmployeeStockOptionMember" xlink:title="EmployeeStockOptionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="EmployeeStockOptionMember" xlink:title="definition: ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain to EmployeeStockOptionMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_FullValueAwardsMember" xlink:label="FullValueAwardsMember" xlink:title="FullValueAwardsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="FullValueAwardsMember" xlink:title="definition: ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain to FullValueAwardsMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_MarketStockUnitsMember" xlink:label="MarketStockUnitsMember" xlink:title="MarketStockUnitsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="MarketStockUnitsMember" xlink:title="definition: ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain to MarketStockUnitsMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="IncomeStatementLocationAxis" xlink:title="IncomeStatementLocationAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="IncomeStatementLocationDomain" xlink:title="IncomeStatementLocationDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="IncomeStatementLocationAxis" xlink:to="IncomeStatementLocationDomain" xlink:title="definition: IncomeStatementLocationAxis to IncomeStatementLocationDomain" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="IncomeStatementLocationDomain_2" xlink:title="IncomeStatementLocationDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="IncomeStatementLocationAxis" xlink:to="IncomeStatementLocationDomain_2" xlink:title="definition: IncomeStatementLocationAxis to IncomeStatementLocationDomain" use="optional" order="8001.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EmployeeStockOptionsAndStockAppreciationRightsMember" xlink:label="EmployeeStockOptionsAndStockAppreciationRightsMember" xlink:title="EmployeeStockOptionsAndStockAppreciationRightsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeStatementLocationDomain" xlink:to="EmployeeStockOptionsAndStockAppreciationRightsMember" xlink:title="definition: IncomeStatementLocationDomain to EmployeeStockOptionsAndStockAppreciationRightsMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="CostOfSalesMember" xlink:title="CostOfSalesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeStockOptionsAndStockAppreciationRightsMember" xlink:to="CostOfSalesMember" xlink:title="definition: EmployeeStockOptionsAndStockAppreciationRightsMember to CostOfSalesMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="ResearchAndDevelopmentExpenseMember" xlink:title="ResearchAndDevelopmentExpenseMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeStockOptionsAndStockAppreciationRightsMember" xlink:to="ResearchAndDevelopmentExpenseMember" xlink:title="definition: EmployeeStockOptionsAndStockAppreciationRightsMember to ResearchAndDevelopmentExpenseMember" use="optional" order="8001.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SellingGeneralAndAdministrativeExpenseMember" xlink:label="SellingGeneralAndAdministrativeExpenseMember" xlink:title="SellingGeneralAndAdministrativeExpenseMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeStockOptionsAndStockAppreciationRightsMember" xlink:to="SellingGeneralAndAdministrativeExpenseMember" xlink:title="definition: EmployeeStockOptionsAndStockAppreciationRightsMember to SellingGeneralAndAdministrativeExpenseMember" use="optional" order="8002.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="PlanNameAxis" xlink:title="PlanNameAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="PlanNameDomain" xlink:title="PlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="PlanNameAxis" xlink:to="PlanNameDomain" xlink:title="definition: PlanNameAxis to PlanNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="PlanNameDomain_2" xlink:title="PlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="PlanNameAxis" xlink:to="PlanNameDomain_2" xlink:title="definition: PlanNameAxis to PlanNameDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_StockIncentivePlan2009Member" xlink:label="StockIncentivePlan2009Member" xlink:title="StockIncentivePlan2009Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PlanNameDomain" xlink:to="StockIncentivePlan2009Member" xlink:title="definition: PlanNameDomain to StockIncentivePlan2009Member" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_StockIncentivePlan2000Member" xlink:label="StockIncentivePlan2000Member" xlink:title="StockIncentivePlan2000Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PlanNameDomain" xlink:to="StockIncentivePlan2000Member" xlink:title="definition: PlanNameDomain to StockIncentivePlan2000Member" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EmployeeStockPurchasePlan2009Member" xlink:label="EmployeeStockPurchasePlan2009Member" xlink:title="EmployeeStockPurchasePlan2009Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PlanNameDomain" xlink:to="EmployeeStockPurchasePlan2009Member" xlink:title="definition: PlanNameDomain to EmployeeStockPurchasePlan2009Member" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:label="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:title="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:label="ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:title="ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:to="PlanNameAxis" xlink:title="definition: ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable to PlanNameAxis" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:to="AwardTypeAxis" xlink:title="definition: ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable to AwardTypeAxis" use="optional" order="2.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:to="IncomeStatementLocationAxis" xlink:title="definition: ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable to IncomeStatementLocationAxis" use="optional" order="3.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:to="RangeAxis" xlink:title="definition: ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable to RangeAxis" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanExpirationDating" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanExpirationDating" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanExpirationDating" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanExpirationDating" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanExpirationDating" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesToBeDeductedFromSharesAvailableForIssuanceForEachShareGranted" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesToBeDeductedFromSharesAvailableForIssuanceForEachShareGranted" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesToBeDeductedFromSharesAvailableForIssuanceForEachShareGranted" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesToBeDeductedFromSharesAvailableForIssuanceForEachShareGranted" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesToBeDeductedFromSharesAvailableForIssuanceForEachShareGranted" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExercisePriceAsPercentageOfGrantDateFairValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExercisePriceAsPercentageOfGrantDateFairValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExercisePriceAsPercentageOfGrantDateFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExercisePriceAsPercentageOfGrantDateFairValue" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExercisePriceAsPercentageOfGrantDateFairValue" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumTermOfOffering" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumTermOfOffering" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumTermOfOffering" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumTermOfOffering" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumTermOfOffering" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementByShareBasedPaymentAwardTerm" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardTerm" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardTerm" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardTerm" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardTerm" use="optional" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" use="optional" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" use="optional" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EmployeeServiceShareBasedCompensationNetReductionInSellingGeneralAndAdministrativeExpense" xlink:label="EmployeeServiceShareBasedCompensationNetReductionInSellingGeneralAndAdministrativeExpense" xlink:title="EmployeeServiceShareBasedCompensationNetReductionInSellingGeneralAndAdministrativeExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="EmployeeServiceShareBasedCompensationNetReductionInSellingGeneralAndAdministrativeExpense" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to EmployeeServiceShareBasedCompensationNetReductionInSellingGeneralAndAdministrativeExpense" use="optional" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" use="optional" order="12.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" use="optional" order="13.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:to="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract to ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:label="SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:title="SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:to="SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract to SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ShareBasedCompensationArrangementCashConsiderationBasedUponAchievementOfSpecifiedLevelsOfMarketConditions" xlink:label="ShareBasedCompensationArrangementCashConsiderationBasedUponAchievementOfSpecifiedLevelsOfMarketConditions" xlink:title="ShareBasedCompensationArrangementCashConsiderationBasedUponAchievementOfSpecifiedLevelsOfMarketConditions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="ShareBasedCompensationArrangementCashConsiderationBasedUponAchievementOfSpecifiedLevelsOfMarketConditions" xlink:title="definition: EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems to ShareBasedCompensationArrangementCashConsiderationBasedUponAchievementOfSpecifiedLevelsOfMarketConditions" use="optional" order="14.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureStockBasedCompensationDetails4">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:title="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:title="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="PlanNameAxis" xlink:title="PlanNameAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="PlanNameAxis" xlink:title="definition: ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable to PlanNameAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="PlanNameDomain" xlink:title="PlanNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="PlanNameAxis" xlink:to="PlanNameDomain" xlink:title="definition: PlanNameAxis to PlanNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_StockIncentivePlan2009Member" xlink:label="StockIncentivePlan2009Member" xlink:title="StockIncentivePlan2009Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PlanNameDomain" xlink:to="StockIncentivePlan2009Member" xlink:title="definition: PlanNameDomain to StockIncentivePlan2009Member" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_StockIncentivePlan2000Member" xlink:label="StockIncentivePlan2000Member" xlink:title="StockIncentivePlan2000Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PlanNameDomain" xlink:to="StockIncentivePlan2000Member" xlink:title="definition: PlanNameDomain to StockIncentivePlan2000Member" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EmployeeStockPurchasePlan2009Member" xlink:label="EmployeeStockPurchasePlan2009Member" xlink:title="EmployeeStockPurchasePlan2009Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PlanNameDomain" xlink:to="EmployeeStockPurchasePlan2009Member" xlink:title="definition: PlanNameDomain to EmployeeStockPurchasePlan2009Member" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="CommonStockCapitalSharesReservedForFutureIssuance" xlink:title="CommonStockCapitalSharesReservedForFutureIssuance" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="CommonStockCapitalSharesReservedForFutureIssuance" xlink:title="definition: ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems to CommonStockCapitalSharesReservedForFutureIssuance" use="optional" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureSignificantAccountingPoliciesDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SummaryOfSignificantAccountingPoliciesLineItems" xlink:label="SummaryOfSignificantAccountingPoliciesLineItems" xlink:title="SummaryOfSignificantAccountingPoliciesLineItems" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SummaryOfSignificantAccountingPoliciesTable" xlink:label="SummaryOfSignificantAccountingPoliciesTable" xlink:title="SummaryOfSignificantAccountingPoliciesTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="SummaryOfSignificantAccountingPoliciesLineItems" xlink:to="SummaryOfSignificantAccountingPoliciesTable" xlink:title="definition: SummaryOfSignificantAccountingPoliciesLineItems to SummaryOfSignificantAccountingPoliciesTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="SummaryOfSignificantAccountingPoliciesTable" xlink:to="RangeAxis" xlink:title="definition: SummaryOfSignificantAccountingPoliciesTable to RangeAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="PropertyPlantAndEquipmentByTypeAxis" xlink:title="PropertyPlantAndEquipmentByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="SummaryOfSignificantAccountingPoliciesTable" xlink:to="PropertyPlantAndEquipmentByTypeAxis" xlink:title="definition: SummaryOfSignificantAccountingPoliciesTable to PropertyPlantAndEquipmentByTypeAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="PropertyPlantAndEquipmentTypeDomain" xlink:title="PropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="PropertyPlantAndEquipmentByTypeAxis" xlink:to="PropertyPlantAndEquipmentTypeDomain" xlink:title="definition: PropertyPlantAndEquipmentByTypeAxis to PropertyPlantAndEquipmentTypeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="PropertyPlantAndEquipmentTypeDomain_2" xlink:title="PropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="PropertyPlantAndEquipmentByTypeAxis" xlink:to="PropertyPlantAndEquipmentTypeDomain_2" xlink:title="definition: PropertyPlantAndEquipmentByTypeAxis to PropertyPlantAndEquipmentTypeDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BuildingMember" xlink:label="BuildingMember" xlink:title="BuildingMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="BuildingMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to BuildingMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LeaseholdInterestInGroundLeasesMember" xlink:label="LeaseholdInterestInGroundLeasesMember" xlink:title="LeaseholdInterestInGroundLeasesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="LeaseholdInterestInGroundLeasesMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to LeaseholdInterestInGroundLeasesMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LengthOfFiscalYear" xlink:label="LengthOfFiscalYear" xlink:title="LengthOfFiscalYear" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SummaryOfSignificantAccountingPoliciesLineItems" xlink:to="LengthOfFiscalYear" xlink:title="definition: SummaryOfSignificantAccountingPoliciesLineItems to LengthOfFiscalYear" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="PropertyPlantAndEquipmentAbstract" xlink:title="PropertyPlantAndEquipmentAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SummaryOfSignificantAccountingPoliciesLineItems" xlink:to="PropertyPlantAndEquipmentAbstract" xlink:title="definition: SummaryOfSignificantAccountingPoliciesLineItems to PropertyPlantAndEquipmentAbstract" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="PropertyPlantAndEquipmentUsefulLife" xlink:title="PropertyPlantAndEquipmentUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentAbstract" xlink:to="PropertyPlantAndEquipmentUsefulLife" xlink:title="definition: PropertyPlantAndEquipmentAbstract to PropertyPlantAndEquipmentUsefulLife" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LongLivedAssetsAbstract" xlink:label="LongLivedAssetsAbstract" xlink:title="LongLivedAssetsAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SummaryOfSignificantAccountingPoliciesLineItems" xlink:to="LongLivedAssetsAbstract" xlink:title="definition: SummaryOfSignificantAccountingPoliciesLineItems to LongLivedAssetsAbstract" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:label="FiniteLivedIntangibleAssetUsefulLife" xlink:title="FiniteLivedIntangibleAssetUsefulLife" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="LongLivedAssetsAbstract" xlink:to="FiniteLivedIntangibleAssetUsefulLife" xlink:title="definition: LongLivedAssetsAbstract to FiniteLivedIntangibleAssetUsefulLife" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_NumberOfDaysInFiscalQuarter52WeekYear" xlink:label="NumberOfDaysInFiscalQuarter52WeekYear" xlink:title="NumberOfDaysInFiscalQuarter52WeekYear" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SummaryOfSignificantAccountingPoliciesLineItems" xlink:to="NumberOfDaysInFiscalQuarter52WeekYear" xlink:title="definition: SummaryOfSignificantAccountingPoliciesLineItems to NumberOfDaysInFiscalQuarter52WeekYear" use="optional" order="8000.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails6">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_WeightedAverageMember" xlink:label="WeightedAverageMember" xlink:title="WeightedAverageMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="WeightedAverageMember" xlink:title="definition: RangeMember to WeightedAverageMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:label="FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:title="FairValueInputsLiabilitiesQuantitativeInformationLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:label="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:title="FairValueInputsLiabilitiesQuantitativeInformationTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:to="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationLineItems to FairValueInputsLiabilitiesQuantitativeInformationTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByLiabilityClassAxis" xlink:label="FairValueByLiabilityClassAxis" xlink:title="FairValueByLiabilityClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:to="FairValueByLiabilityClassAxis" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationTable to FairValueByLiabilityClassAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:title="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByLiabilityClassAxis" xlink:to="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:title="definition: FairValueByLiabilityClassAxis to FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ContingentConsiderationMember" xlink:label="ContingentConsiderationMember" xlink:title="ContingentConsiderationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:to="ContingentConsiderationMember" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain to ContingentConsiderationMember" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:to="RangeAxis" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationTable to RangeAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationTechniqueAxis" xlink:label="ValuationTechniqueAxis" xlink:title="ValuationTechniqueAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsLiabilitiesQuantitativeInformationTable" xlink:to="ValuationTechniqueAxis" xlink:title="definition: FairValueInputsLiabilitiesQuantitativeInformationTable to ValuationTechniqueAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationTechniqueDomain" xlink:label="ValuationTechniqueDomain" xlink:title="ValuationTechniqueDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ValuationTechniqueAxis" xlink:to="ValuationTechniqueDomain" xlink:title="definition: ValuationTechniqueAxis to ValuationTechniqueDomain" use="optional" order="1.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureCashCashEquivalentsAndInvestmentsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="8001.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:title="ScheduleOfAvailableForSaleSecuritiesLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="ScheduleOfAvailableForSaleSecuritiesTable" xlink:title="ScheduleOfAvailableForSaleSecuritiesTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="ScheduleOfAvailableForSaleSecuritiesTable" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to ScheduleOfAvailableForSaleSecuritiesTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:title="MajorTypesOfDebtAndEquitySecuritiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfAvailableForSaleSecuritiesTable" xlink:to="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesTable to MajorTypesOfDebtAndEquitySecuritiesAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:title="MajorTypesOfDebtAndEquitySecuritiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:to="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesAxis to MajorTypesOfDebtAndEquitySecuritiesDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="MajorTypesOfDebtAndEquitySecuritiesDomain_2" xlink:title="MajorTypesOfDebtAndEquitySecuritiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:to="MajorTypesOfDebtAndEquitySecuritiesDomain_2" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesAxis to MajorTypesOfDebtAndEquitySecuritiesDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_USTreasuryBillSecuritiesMember" xlink:label="USTreasuryBillSecuritiesMember" xlink:title="USTreasuryBillSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="USTreasuryBillSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to USTreasuryBillSecuritiesMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="MoneyMarketFundsMember" xlink:title="MoneyMarketFundsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="MoneyMarketFundsMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to MoneyMarketFundsMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CommercialPaperMember" xlink:label="CommercialPaperMember" xlink:title="CommercialPaperMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="CommercialPaperMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to CommercialPaperMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CertificatesOfDepositMember" xlink:label="CertificatesOfDepositMember" xlink:title="CertificatesOfDepositMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="CertificatesOfDepositMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to CertificatesOfDepositMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="CorporateDebtSecuritiesMember" xlink:title="CorporateDebtSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="CorporateDebtSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to CorporateDebtSecuritiesMember" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MunicipalBondsMember" xlink:label="MunicipalBondsMember" xlink:title="MunicipalBondsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="MunicipalBondsMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to MunicipalBondsMember" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_VariableRateDemandObligationMember" xlink:label="VariableRateDemandObligationMember" xlink:title="VariableRateDemandObligationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="VariableRateDemandObligationMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to VariableRateDemandObligationMember" use="optional" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="AssetBackedSecuritiesMember" xlink:title="AssetBackedSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="AssetBackedSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to AssetBackedSecuritiesMember" use="optional" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_USTreasuryAndGovernmentMember" xlink:label="USTreasuryAndGovernmentMember" xlink:title="USTreasuryAndGovernmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="USTreasuryAndGovernmentMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to USTreasuryAndGovernmentMember" use="optional" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember" xlink:label="ForeignGovernmentDebtSecuritiesMember" xlink:title="ForeignGovernmentDebtSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="ForeignGovernmentDebtSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to ForeignGovernmentDebtSecuritiesMember" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AuctionRateSecuritiesMember" xlink:label="AuctionRateSecuritiesMember" xlink:title="AuctionRateSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="AuctionRateSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to AuctionRateSecuritiesMember" use="optional" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InvestmentTypeAxis" xlink:label="InvestmentTypeAxis" xlink:title="InvestmentTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfAvailableForSaleSecuritiesTable" xlink:to="InvestmentTypeAxis" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesTable to InvestmentTypeAxis" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="InvestmentTypeCategorizationMember" xlink:title="InvestmentTypeCategorizationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="InvestmentTypeAxis" xlink:to="InvestmentTypeCategorizationMember" xlink:title="definition: InvestmentTypeAxis to InvestmentTypeCategorizationMember" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="InvestmentTypeCategorizationMember_2" xlink:title="InvestmentTypeCategorizationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="InvestmentTypeAxis" xlink:to="InvestmentTypeCategorizationMember_2" xlink:title="definition: InvestmentTypeAxis to InvestmentTypeCategorizationMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CashEquivalentsMember" xlink:label="CashEquivalentsMember" xlink:title="CashEquivalentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="CashEquivalentsMember" xlink:title="definition: InvestmentTypeCategorizationMember to CashEquivalentsMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShortTermInvestmentsMember" xlink:label="ShortTermInvestmentsMember" xlink:title="ShortTermInvestmentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="ShortTermInvestmentsMember" xlink:title="definition: InvestmentTypeCategorizationMember to ShortTermInvestmentsMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LongTermInvestmentsMember" xlink:label="LongTermInvestmentsMember" xlink:title="LongTermInvestmentsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="LongTermInvestmentsMember" xlink:title="definition: InvestmentTypeCategorizationMember to LongTermInvestmentsMember" use="optional" order="3.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfAvailableForSaleSecuritiesTable" xlink:to="RangeAxis" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesTable to RangeAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:label="AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:title="AvailableForSaleDebtSecuritiesAmortizedCostBasis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to AvailableForSaleDebtSecuritiesAmortizedCostBasis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments" xlink:label="AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments" xlink:title="AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to AvailableForSaleSecuritiesGrossUnrealizedLossAccumulatedInInvestments" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments" xlink:label="AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments" xlink:title="AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to AvailableForSaleSecuritiesGrossUnrealizedGainAccumulatedInInvestments" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecurities" xlink:label="AvailableForSaleSecurities" xlink:title="AvailableForSaleSecurities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="AvailableForSaleSecurities" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to AvailableForSaleSecurities" use="optional" order="5.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails2">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember_2" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="RangeAxis" xlink:to="RangeMember_2" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_WeightedAverageMember" xlink:label="WeightedAverageMember" xlink:title="WeightedAverageMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="WeightedAverageMember" xlink:title="definition: RangeMember to WeightedAverageMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationTechniqueAxis" xlink:label="ValuationTechniqueAxis" xlink:title="ValuationTechniqueAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationTechniqueDomain" xlink:label="ValuationTechniqueDomain" xlink:title="ValuationTechniqueDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ValuationTechniqueAxis" xlink:to="ValuationTechniqueDomain" xlink:title="definition: ValuationTechniqueAxis to ValuationTechniqueDomain" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ValuationTechniqueDomain" xlink:label="ValuationTechniqueDomain_2" xlink:title="ValuationTechniqueDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ValuationTechniqueAxis" xlink:to="ValuationTechniqueDomain_2" xlink:title="definition: ValuationTechniqueAxis to ValuationTechniqueDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_DiscountedCashFlowValuationTechniqueMember" xlink:label="DiscountedCashFlowValuationTechniqueMember" xlink:title="DiscountedCashFlowValuationTechniqueMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ValuationTechniqueDomain" xlink:to="DiscountedCashFlowValuationTechniqueMember" xlink:title="definition: ValuationTechniqueDomain to DiscountedCashFlowValuationTechniqueMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsAssetsQuantitativeInformationLineItems" xlink:label="FairValueInputsAssetsQuantitativeInformationLineItems" xlink:title="FairValueInputsAssetsQuantitativeInformationLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsAssetsQuantitativeInformationTable" xlink:label="FairValueInputsAssetsQuantitativeInformationTable" xlink:title="FairValueInputsAssetsQuantitativeInformationTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FairValueInputsAssetsQuantitativeInformationLineItems" xlink:to="FairValueInputsAssetsQuantitativeInformationTable" xlink:title="definition: FairValueInputsAssetsQuantitativeInformationLineItems to FairValueInputsAssetsQuantitativeInformationTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="FairValueByAssetClassAxis" xlink:title="FairValueByAssetClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsAssetsQuantitativeInformationTable" xlink:to="FairValueByAssetClassAxis" xlink:title="definition: FairValueInputsAssetsQuantitativeInformationTable to FairValueByAssetClassAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:title="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByAssetClassAxis" xlink:to="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:title="definition: FairValueByAssetClassAxis to FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AuctionRateSecuritiesMember" xlink:label="AuctionRateSecuritiesMember" xlink:title="AuctionRateSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:to="AuctionRateSecuritiesMember" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain to AuctionRateSecuritiesMember" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsAssetsQuantitativeInformationTable" xlink:to="RangeAxis" xlink:title="definition: FairValueInputsAssetsQuantitativeInformationTable to RangeAxis" use="optional" order="2.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueInputsAssetsQuantitativeInformationTable" xlink:to="ValuationTechniqueAxis" xlink:title="definition: FairValueInputsAssetsQuantitativeInformationTable to ValuationTechniqueAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_FairValueInputsEstimatedInterestRates" xlink:label="FairValueInputsEstimatedInterestRates" xlink:title="FairValueInputsEstimatedInterestRates" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueInputsAssetsQuantitativeInformationLineItems" xlink:to="FairValueInputsEstimatedInterestRates" xlink:title="definition: FairValueInputsAssetsQuantitativeInformationLineItems to FairValueInputsEstimatedInterestRates" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_FairValueInputsExpectedHoldingPeriods" xlink:label="FairValueInputsExpectedHoldingPeriods" xlink:title="FairValueInputsExpectedHoldingPeriods" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueInputsAssetsQuantitativeInformationLineItems" xlink:to="FairValueInputsExpectedHoldingPeriods" xlink:title="definition: FairValueInputsAssetsQuantitativeInformationLineItems to FairValueInputsExpectedHoldingPeriods" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_FairValueInputsLiquidityDiscount" xlink:label="FairValueInputsLiquidityDiscount" xlink:title="FairValueInputsLiquidityDiscount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueInputsAssetsQuantitativeInformationLineItems" xlink:to="FairValueInputsLiquidityDiscount" xlink:title="definition: FairValueInputsAssetsQuantitativeInformationLineItems to FairValueInputsLiquidityDiscount" use="optional" order="4.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureAcquisitionDetails2">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain_2" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain_2" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EmberCorporationMember" xlink:label="EmberCorporationMember" xlink:title="EmberCorporationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="EmberCorporationMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to EmberCorporationMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_HeadquartersLeasesMember" xlink:label="HeadquartersLeasesMember" xlink:title="HeadquartersLeasesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="HeadquartersLeasesMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to HeadquartersLeasesMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_WCesarChavez400Member" xlink:label="WCesarChavez400Member" xlink:title="WCesarChavez400Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="HeadquartersLeasesMember" xlink:to="WCesarChavez400Member" xlink:title="definition: HeadquartersLeasesMember to WCesarChavez400Member" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SpectraLinearIncMember" xlink:label="SpectraLinearIncMember" xlink:title="SpectraLinearIncMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="SpectraLinearIncMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to SpectraLinearIncMember" use="optional" order="8001.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="BusinessAcquisitionLineItems" xlink:title="BusinessAcquisitionLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="ScheduleOfBusinessAcquisitionsByAcquisitionTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="BusinessAcquisitionLineItems" xlink:to="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="definition: BusinessAcquisitionLineItems to ScheduleOfBusinessAcquisitionsByAcquisitionTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to BusinessAcquisitionAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="IndefiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to IndefiniteLivedIntangibleAssetsByMajorClassAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: IndefiniteLivedIntangibleAssetsByMajorClassAxis to IndefiniteLivedIntangibleAssetsMajorClassNameDomain" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="IndefiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="IndefiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="IndefiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="IndefiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="definition: IndefiniteLivedIntangibleAssetsByMajorClassAxis to IndefiniteLivedIntangibleAssetsMajorClassNameDomain" use="optional" order="8001.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="FiniteLivedIntangibleAssetsByMajorClassAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to FiniteLivedIntangibleAssetsByMajorClassAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DevelopedTechnologyRightsMember" xlink:label="DevelopedTechnologyRightsMember" xlink:title="DevelopedTechnologyRightsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="DevelopedTechnologyRightsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to DevelopedTechnologyRightsMember" use="optional" order="8001.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CustomerRelationshipsMember" xlink:label="CustomerRelationshipsMember" xlink:title="CustomerRelationshipsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="CustomerRelationshipsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to CustomerRelationshipsMember" use="optional" order="8002.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_TrademarksMember" xlink:label="TrademarksMember" xlink:title="TrademarksMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="TrademarksMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to TrademarksMember" use="optional" order="8003.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_CoreAndDevelopedTechnologyMember" xlink:label="CoreAndDevelopedTechnologyMember" xlink:title="CoreAndDevelopedTechnologyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="CoreAndDevelopedTechnologyMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to CoreAndDevelopedTechnologyMember" use="optional" order="8000.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureRisksAndUncertaintiesDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskLineItems" xlink:label="ConcentrationRiskLineItems" xlink:title="ConcentrationRiskLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskTable" xlink:label="ConcentrationRiskTable" xlink:title="ConcentrationRiskTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="ConcentrationRiskLineItems" xlink:to="ConcentrationRiskTable" xlink:title="definition: ConcentrationRiskLineItems to ConcentrationRiskTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="ConcentrationRiskByBenchmarkAxis" xlink:title="ConcentrationRiskByBenchmarkAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ConcentrationRiskTable" xlink:to="ConcentrationRiskByBenchmarkAxis" xlink:title="definition: ConcentrationRiskTable to ConcentrationRiskByBenchmarkAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="ConcentrationRiskBenchmarkDomain" xlink:title="ConcentrationRiskBenchmarkDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ConcentrationRiskByBenchmarkAxis" xlink:to="ConcentrationRiskBenchmarkDomain" xlink:title="definition: ConcentrationRiskByBenchmarkAxis to ConcentrationRiskBenchmarkDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccountsReceivableMember" xlink:label="AccountsReceivableMember" xlink:title="AccountsReceivableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskBenchmarkDomain" xlink:to="AccountsReceivableMember" xlink:title="definition: ConcentrationRiskBenchmarkDomain to AccountsReceivableMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SalesRevenueGoodsNetMember" xlink:label="SalesRevenueGoodsNetMember" xlink:title="SalesRevenueGoodsNetMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskBenchmarkDomain" xlink:to="SalesRevenueGoodsNetMember" xlink:title="definition: ConcentrationRiskBenchmarkDomain to SalesRevenueGoodsNetMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="ConcentrationRiskByTypeAxis" xlink:title="ConcentrationRiskByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ConcentrationRiskTable" xlink:to="ConcentrationRiskByTypeAxis" xlink:title="definition: ConcentrationRiskTable to ConcentrationRiskByTypeAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="ConcentrationRiskTypeDomain" xlink:title="ConcentrationRiskTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ConcentrationRiskByTypeAxis" xlink:to="ConcentrationRiskTypeDomain" xlink:title="definition: ConcentrationRiskByTypeAxis to ConcentrationRiskTypeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CustomerConcentrationRiskMember" xlink:label="CustomerConcentrationRiskMember" xlink:title="CustomerConcentrationRiskMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="CustomerConcentrationRiskMember" xlink:title="definition: ConcentrationRiskTypeDomain to CustomerConcentrationRiskMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorCustomersAxis" xlink:label="MajorCustomersAxis" xlink:title="MajorCustomersAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ConcentrationRiskTable" xlink:to="MajorCustomersAxis" xlink:title="definition: ConcentrationRiskTable to MajorCustomersAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_NameOfMajorCustomerDomain" xlink:label="NameOfMajorCustomerDomain" xlink:title="NameOfMajorCustomerDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="MajorCustomersAxis" xlink:to="NameOfMajorCustomerDomain" xlink:title="definition: MajorCustomersAxis to NameOfMajorCustomerDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_NameOfMajorCustomerDomain" xlink:label="NameOfMajorCustomerDomain_2" xlink:title="NameOfMajorCustomerDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="MajorCustomersAxis" xlink:to="NameOfMajorCustomerDomain_2" xlink:title="definition: MajorCustomersAxis to NameOfMajorCustomerDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_DistributorsMember" xlink:label="DistributorsMember" xlink:title="DistributorsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="NameOfMajorCustomerDomain" xlink:to="DistributorsMember" xlink:title="definition: NameOfMajorCustomerDomain to DistributorsMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EdomTechnologyMember" xlink:label="EdomTechnologyMember" xlink:title="EdomTechnologyMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DistributorsMember" xlink:to="EdomTechnologyMember" xlink:title="definition: DistributorsMember to EdomTechnologyMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ArrowElectronicsMember" xlink:label="ArrowElectronicsMember" xlink:title="ArrowElectronicsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DistributorsMember" xlink:to="ArrowElectronicsMember" xlink:title="definition: DistributorsMember to ArrowElectronicsMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AvnetMember" xlink:label="AvnetMember" xlink:title="AvnetMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DistributorsMember" xlink:to="AvnetMember" xlink:title="definition: DistributorsMember to AvnetMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_MacnicaMember" xlink:label="MacnicaMember" xlink:title="MacnicaMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DistributorsMember" xlink:to="MacnicaMember" xlink:title="definition: DistributorsMember to MacnicaMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EndCustomersMember" xlink:label="EndCustomersMember" xlink:title="EndCustomersMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="NameOfMajorCustomerDomain" xlink:to="EndCustomersMember" xlink:title="definition: NameOfMajorCustomerDomain to EndCustomersMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SamsungMember" xlink:label="SamsungMember" xlink:title="SamsungMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EndCustomersMember" xlink:to="SamsungMember" xlink:title="definition: EndCustomersMember to SamsungMember" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ConcentrationRiskTable" xlink:to="RangeAxis" xlink:title="definition: ConcentrationRiskTable to RangeAxis" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskPercentage1" xlink:label="ConcentrationRiskPercentage1" xlink:title="ConcentrationRiskPercentage1" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskLineItems" xlink:to="ConcentrationRiskPercentage1" xlink:title="definition: ConcentrationRiskLineItems to ConcentrationRiskPercentage1" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_InterestRateOnUnsettledBalancesDueUponDemand" xlink:label="InterestRateOnUnsettledBalancesDueUponDemand" xlink:title="InterestRateOnUnsettledBalancesDueUponDemand" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskLineItems" xlink:to="InterestRateOnUnsettledBalancesDueUponDemand" xlink:title="definition: ConcentrationRiskLineItems to InterestRateOnUnsettledBalancesDueUponDemand" use="optional" order="3.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureIncomeTaxesDetails2">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EnergyMicroMember" xlink:label="EnergyMicroMember" xlink:title="EnergyMicroMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="EnergyMicroMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to EnergyMicroMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_CygnalIntegratedProductsAndSiliconClocksIncSpectraLinearAndEmberMember" xlink:label="CygnalIntegratedProductsAndSiliconClocksIncSpectraLinearAndEmberMember" xlink:title="CygnalIntegratedProductsAndSiliconClocksIncSpectraLinearAndEmberMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="CygnalIntegratedProductsAndSiliconClocksIncSpectraLinearAndEmberMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to CygnalIntegratedProductsAndSiliconClocksIncSpectraLinearAndEmberMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MinimumMember" xlink:label="MinimumMember" xlink:title="MinimumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MinimumMember" xlink:title="definition: RangeMember to MinimumMember" use="optional" order="8001.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_OperatingLossAndTaxCreditCarryforwardLineItems" xlink:label="OperatingLossAndTaxCreditCarryforwardLineItems" xlink:title="OperatingLossAndTaxCreditCarryforwardLineItems" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" xlink:label="ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" xlink:title="ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="OperatingLossAndTaxCreditCarryforwardLineItems" xlink:to="ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" xlink:title="definition: OperatingLossAndTaxCreditCarryforwardLineItems to ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfOperatingLossAndTaxCreditCarryforwardTable to BusinessAcquisitionAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeTaxAuthorityAxis" xlink:label="IncomeTaxAuthorityAxis" xlink:title="IncomeTaxAuthorityAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" xlink:to="IncomeTaxAuthorityAxis" xlink:title="definition: ScheduleOfOperatingLossAndTaxCreditCarryforwardTable to IncomeTaxAuthorityAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="IncomeTaxAuthorityDomain" xlink:title="IncomeTaxAuthorityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="IncomeTaxAuthorityAxis" xlink:to="IncomeTaxAuthorityDomain" xlink:title="definition: IncomeTaxAuthorityAxis to IncomeTaxAuthorityDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="IncomeTaxAuthorityDomain_2" xlink:title="IncomeTaxAuthorityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="IncomeTaxAuthorityAxis" xlink:to="IncomeTaxAuthorityDomain_2" xlink:title="definition: IncomeTaxAuthorityAxis to IncomeTaxAuthorityDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DomesticCountryMember" xlink:label="DomesticCountryMember" xlink:title="DomesticCountryMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeTaxAuthorityDomain" xlink:to="DomesticCountryMember" xlink:title="definition: IncomeTaxAuthorityDomain to DomesticCountryMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StateAndLocalJurisdictionMember" xlink:label="StateAndLocalJurisdictionMember" xlink:title="StateAndLocalJurisdictionMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeTaxAuthorityDomain" xlink:to="StateAndLocalJurisdictionMember" xlink:title="definition: IncomeTaxAuthorityDomain to StateAndLocalJurisdictionMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ForeignCountryMember" xlink:label="ForeignCountryMember" xlink:title="ForeignCountryMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeTaxAuthorityDomain" xlink:to="ForeignCountryMember" xlink:title="definition: IncomeTaxAuthorityDomain to ForeignCountryMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementGeographicalAxis" xlink:label="StatementGeographicalAxis" xlink:title="StatementGeographicalAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" xlink:to="StatementGeographicalAxis" xlink:title="definition: ScheduleOfOperatingLossAndTaxCreditCarryforwardTable to StatementGeographicalAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="SegmentGeographicalDomain" xlink:title="SegmentGeographicalDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="StatementGeographicalAxis" xlink:to="SegmentGeographicalDomain" xlink:title="definition: StatementGeographicalAxis to SegmentGeographicalDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd#country_SG" xlink:label="SG" xlink:title="SG" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SegmentGeographicalDomain" xlink:to="SG" xlink:title="definition: SegmentGeographicalDomain to SG" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfOperatingLossAndTaxCreditCarryforwardTable" xlink:to="RangeAxis" xlink:title="definition: ScheduleOfOperatingLossAndTaxCreditCarryforwardTable to RangeAxis" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_OperatingLossCarryforwards" xlink:label="OperatingLossCarryforwards" xlink:title="OperatingLossCarryforwards" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="OperatingLossAndTaxCreditCarryforwardLineItems" xlink:to="OperatingLossCarryforwards" xlink:title="definition: OperatingLossAndTaxCreditCarryforwardLineItems to OperatingLossCarryforwards" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_TaxCreditCarryforwardAmount" xlink:label="TaxCreditCarryforwardAmount" xlink:title="TaxCreditCarryforwardAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="OperatingLossAndTaxCreditCarryforwardLineItems" xlink:to="TaxCreditCarryforwardAmount" xlink:title="definition: OperatingLossAndTaxCreditCarryforwardLineItems to TaxCreditCarryforwardAmount" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:label="DeferredTaxAssetsLiabilitiesNet" xlink:title="DeferredTaxAssetsLiabilitiesNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="OperatingLossAndTaxCreditCarryforwardLineItems" xlink:to="DeferredTaxAssetsLiabilitiesNet" xlink:title="definition: OperatingLossAndTaxCreditCarryforwardLineItems to DeferredTaxAssetsLiabilitiesNet" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ProvisionForUndistributedEarningsFromForeignSubsidiaries" xlink:label="ProvisionForUndistributedEarningsFromForeignSubsidiaries" xlink:title="ProvisionForUndistributedEarningsFromForeignSubsidiaries" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="OperatingLossAndTaxCreditCarryforwardLineItems" xlink:to="ProvisionForUndistributedEarningsFromForeignSubsidiaries" xlink:title="definition: OperatingLossAndTaxCreditCarryforwardLineItems to ProvisionForUndistributedEarningsFromForeignSubsidiaries" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="IncomeTaxExpenseBenefit" xlink:title="IncomeTaxExpenseBenefit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="OperatingLossAndTaxCreditCarryforwardLineItems" xlink:to="IncomeTaxExpenseBenefit" xlink:title="definition: OperatingLossAndTaxCreditCarryforwardLineItems to IncomeTaxExpenseBenefit" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_IncomeTaxBenefitPerDilutedShare" xlink:label="IncomeTaxBenefitPerDilutedShare" xlink:title="IncomeTaxBenefitPerDilutedShare" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="OperatingLossAndTaxCreditCarryforwardLineItems" xlink:to="IncomeTaxBenefitPerDilutedShare" xlink:title="definition: OperatingLossAndTaxCreditCarryforwardLineItems to IncomeTaxBenefitPerDilutedShare" use="optional" order="7.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureStockholdersEquityDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeAxis" xlink:label="RangeAxis" xlink:title="RangeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RangeMember" xlink:label="RangeMember" xlink:title="RangeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="RangeAxis" xlink:to="RangeMember" xlink:title="definition: RangeAxis to RangeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumMember" xlink:label="MaximumMember" xlink:title="MaximumMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RangeMember" xlink:to="MaximumMember" xlink:title="definition: RangeMember to MaximumMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementLineItems" xlink:label="StatementLineItems" xlink:title="StatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementTable" xlink:label="StatementTable" xlink:title="StatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="StatementLineItems" xlink:to="StatementTable" xlink:title="definition: StatementLineItems to StatementTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="StatementTable" xlink:to="RangeAxis" xlink:title="definition: StatementTable to RangeAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="StatementEquityComponentsAxis" xlink:title="StatementEquityComponentsAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="StatementTable" xlink:to="StatementEquityComponentsAxis" xlink:title="definition: StatementTable to StatementEquityComponentsAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="EquityComponentDomain" xlink:title="EquityComponentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="StatementEquityComponentsAxis" xlink:to="EquityComponentDomain" xlink:title="definition: StatementEquityComponentsAxis to EquityComponentDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="EquityComponentDomain_2" xlink:title="EquityComponentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="StatementEquityComponentsAxis" xlink:to="EquityComponentDomain_2" xlink:title="definition: StatementEquityComponentsAxis to EquityComponentDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:label="AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:title="AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:title="definition: EquityComponentDomain to AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:label="AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:title="AccumulatedNetUnrealizedInvestmentGainLossMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:title="definition: EquityComponentDomain to AccumulatedNetUnrealizedInvestmentGainLossMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockRepurchaseProgramAuthorizedAmount" xlink:label="StockRepurchaseProgramAuthorizedAmount" xlink:title="StockRepurchaseProgramAuthorizedAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="StockRepurchaseProgramAuthorizedAmount" xlink:title="definition: StatementLineItems to StockRepurchaseProgramAuthorizedAmount" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" xlink:label="AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" xlink:title="AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" xlink:title="definition: StatementLineItems to AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:title="AccumulatedOtherComprehensiveIncomeLossNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" xlink:to="AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:title="definition: AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward to AccumulatedOtherComprehensiveIncomeLossNetOfTax" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax" xlink:label="OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax" xlink:title="OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" xlink:to="OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax" xlink:title="definition: AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward to OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" xlink:label="ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" xlink:title="ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" xlink:to="ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" xlink:title="definition: AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward to ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:label="OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:title="OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward" xlink:to="OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:title="definition: AccumulatedOtherComprehensiveIncomeLossNetOfTaxRollForward to OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" use="optional" order="4.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails4">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="FairValueByAssetClassAxis" xlink:title="FairValueByAssetClassAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:title="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByAssetClassAxis" xlink:to="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:title="definition: FairValueByAssetClassAxis to FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_2" xlink:title="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FairValueByAssetClassAxis" xlink:to="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_2" xlink:title="definition: FairValueByAssetClassAxis to FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AuctionRateSecuritiesMember" xlink:label="AuctionRateSecuritiesMember" xlink:title="AuctionRateSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:to="AuctionRateSecuritiesMember" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain to AuctionRateSecuritiesMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:label="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:title="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:label="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:title="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:to="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems to FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="FairValueByMeasurementFrequencyAxis" xlink:title="FairValueByMeasurementFrequencyAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:to="FairValueByMeasurementFrequencyAxis" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable to FairValueByMeasurementFrequencyAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="FairValueMeasurementFrequencyDomain" xlink:title="FairValueMeasurementFrequencyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByMeasurementFrequencyAxis" xlink:to="FairValueMeasurementFrequencyDomain" xlink:title="definition: FairValueByMeasurementFrequencyAxis to FairValueMeasurementFrequencyDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementsRecurringMember" xlink:label="FairValueMeasurementsRecurringMember" xlink:title="FairValueMeasurementsRecurringMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueMeasurementFrequencyDomain" xlink:to="FairValueMeasurementsRecurringMember" xlink:title="definition: FairValueMeasurementFrequencyDomain to FairValueMeasurementsRecurringMember" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:to="FairValueByAssetClassAxis" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable to FairValueByAssetClassAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:label="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:title="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:to="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems to FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" xlink:label="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" xlink:title="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward to FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss" xlink:label="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss" xlink:title="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward to FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:label="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:title="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:title="definition: FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward to FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" use="optional" order="3.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails5">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByLiabilityClassAxis" xlink:label="FairValueByLiabilityClassAxis" xlink:title="FairValueByLiabilityClassAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:title="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByLiabilityClassAxis" xlink:to="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:title="definition: FairValueByLiabilityClassAxis to FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_2" xlink:title="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FairValueByLiabilityClassAxis" xlink:to="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_2" xlink:title="definition: FairValueByLiabilityClassAxis to FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ContingentConsiderationMember" xlink:label="ContingentConsiderationMember" xlink:title="ContingentConsiderationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:to="ContingentConsiderationMember" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain to ContingentConsiderationMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="FairValueByMeasurementFrequencyAxis" xlink:title="FairValueByMeasurementFrequencyAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="FairValueMeasurementFrequencyDomain" xlink:title="FairValueMeasurementFrequencyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByMeasurementFrequencyAxis" xlink:to="FairValueMeasurementFrequencyDomain" xlink:title="definition: FairValueByMeasurementFrequencyAxis to FairValueMeasurementFrequencyDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementsRecurringMember" xlink:label="FairValueMeasurementsRecurringMember" xlink:title="FairValueMeasurementsRecurringMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueMeasurementFrequencyDomain" xlink:to="FairValueMeasurementsRecurringMember" xlink:title="definition: FairValueMeasurementFrequencyDomain to FairValueMeasurementsRecurringMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:label="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:title="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:label="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:title="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:to="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems to FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:to="FairValueByMeasurementFrequencyAxis" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable to FairValueByMeasurementFrequencyAxis" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:to="FairValueByLiabilityClassAxis" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable to FairValueByLiabilityClassAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:label="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:title="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:to="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems to FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:label="FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:title="FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward to FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues" xlink:label="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues" xlink:title="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward to FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" xlink:label="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" xlink:title="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward to FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLossIncludedInSellingGeneralAndAdministrativeExpenseOrOtherIncome" xlink:label="FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLossIncludedInSellingGeneralAndAdministrativeExpenseOrOtherIncome" xlink:title="FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLossIncludedInSellingGeneralAndAdministrativeExpenseOrOtherIncome" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLossIncludedInSellingGeneralAndAdministrativeExpenseOrOtherIncome" xlink:title="definition: FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward to FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLossIncludedInSellingGeneralAndAdministrativeExpenseOrOtherIncome" use="optional" order="4.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureCashCashEquivalentsAndInvestmentsDetails2">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:title="ScheduleOfAvailableForSaleSecuritiesLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="ScheduleOfAvailableForSaleSecuritiesTable" xlink:title="ScheduleOfAvailableForSaleSecuritiesTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="ScheduleOfAvailableForSaleSecuritiesTable" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to ScheduleOfAvailableForSaleSecuritiesTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:title="MajorTypesOfDebtAndEquitySecuritiesAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfAvailableForSaleSecuritiesTable" xlink:to="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesTable to MajorTypesOfDebtAndEquitySecuritiesAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:title="MajorTypesOfDebtAndEquitySecuritiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:to="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesAxis to MajorTypesOfDebtAndEquitySecuritiesDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="CorporateDebtSecuritiesMember" xlink:title="CorporateDebtSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="CorporateDebtSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to CorporateDebtSecuritiesMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MunicipalBondsMember" xlink:label="MunicipalBondsMember" xlink:title="MunicipalBondsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="MunicipalBondsMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to MunicipalBondsMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="AssetBackedSecuritiesMember" xlink:title="AssetBackedSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="AssetBackedSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to AssetBackedSecuritiesMember" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AuctionRateSecuritiesMember" xlink:label="AuctionRateSecuritiesMember" xlink:title="AuctionRateSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="AuctionRateSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to AuctionRateSecuritiesMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract" xlink:label="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract" xlink:title="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" xlink:label="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" xlink:title="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract" xlink:to="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" xlink:title="definition: AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract to AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" xlink:label="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" xlink:title="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract" xlink:to="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" xlink:title="definition: AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract to AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue" xlink:label="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue" xlink:title="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract" xlink:to="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue" xlink:title="definition: AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValueAbstract to AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract" xlink:label="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract" xlink:title="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLossesAccumulatedInInvestments" xlink:label="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLossesAccumulatedInInvestments" xlink:title="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLossesAccumulatedInInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract" xlink:to="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLossesAccumulatedInInvestments" xlink:title="definition: AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract to AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLossesAccumulatedInInvestments" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLossesAccumulatedInInvestments" xlink:label="AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLossesAccumulatedInInvestments" xlink:title="AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLossesAccumulatedInInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract" xlink:to="AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLossesAccumulatedInInvestments" xlink:title="definition: AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract to AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLossesAccumulatedInInvestments" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAccumulatedInInvestments" xlink:label="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAccumulatedInInvestments" xlink:title="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAccumulatedInInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract" xlink:to="AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAccumulatedInInvestments" xlink:title="definition: AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAbstract to AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAggregateLossesAccumulatedInInvestments" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" xlink:title="definition: AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract to AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsAmortizedCost" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsAmortizedCost" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsAmortizedCost" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsAmortizedCost" xlink:title="definition: AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract to AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsAmortizedCost" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost" xlink:title="definition: AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract to AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost" xlink:title="definition: AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract to AvailableForSaleSecuritiesDebtMaturitiesAmortizedCost" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:title="definition: ScheduleOfAvailableForSaleSecuritiesLineItems to AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" xlink:title="definition: AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract to AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsFairValue" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsFairValue" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsFairValue" xlink:title="definition: AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract to AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTenYearsFairValue" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" xlink:label="AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" xlink:title="AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:to="AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" xlink:title="definition: AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract to AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:label="AvailableForSaleSecuritiesDebtSecurities" xlink:title="AvailableForSaleSecuritiesDebtSecurities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract" xlink:to="AvailableForSaleSecuritiesDebtSecurities" xlink:title="definition: AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract to AvailableForSaleSecuritiesDebtSecurities" use="optional" order="4.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureFairValueOfFinancialInstrumentsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:title="MajorTypesOfDebtAndEquitySecuritiesAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:title="MajorTypesOfDebtAndEquitySecuritiesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:to="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesAxis to MajorTypesOfDebtAndEquitySecuritiesDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_USTreasuryBillSecuritiesMember" xlink:label="USTreasuryBillSecuritiesMember" xlink:title="USTreasuryBillSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="USTreasuryBillSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to USTreasuryBillSecuritiesMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="MoneyMarketFundsMember" xlink:title="MoneyMarketFundsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="MoneyMarketFundsMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to MoneyMarketFundsMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CommercialPaperMember" xlink:label="CommercialPaperMember" xlink:title="CommercialPaperMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="CommercialPaperMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to CommercialPaperMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CertificatesOfDepositMember" xlink:label="CertificatesOfDepositMember" xlink:title="CertificatesOfDepositMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="CertificatesOfDepositMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to CertificatesOfDepositMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="CorporateDebtSecuritiesMember" xlink:title="CorporateDebtSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="CorporateDebtSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to CorporateDebtSecuritiesMember" use="optional" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MunicipalBondsMember" xlink:label="MunicipalBondsMember" xlink:title="MunicipalBondsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="MunicipalBondsMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to MunicipalBondsMember" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_VariableRateDemandObligationMember" xlink:label="VariableRateDemandObligationMember" xlink:title="VariableRateDemandObligationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="VariableRateDemandObligationMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to VariableRateDemandObligationMember" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="AssetBackedSecuritiesMember" xlink:title="AssetBackedSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="AssetBackedSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to AssetBackedSecuritiesMember" use="optional" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_USTreasuryAndGovernmentMember" xlink:label="USTreasuryAndGovernmentMember" xlink:title="USTreasuryAndGovernmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="USTreasuryAndGovernmentMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to USTreasuryAndGovernmentMember" use="optional" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember" xlink:label="ForeignGovernmentDebtSecuritiesMember" xlink:title="ForeignGovernmentDebtSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="ForeignGovernmentDebtSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to ForeignGovernmentDebtSecuritiesMember" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AuctionRateSecuritiesMember" xlink:label="AuctionRateSecuritiesMember" xlink:title="AuctionRateSecuritiesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:to="AuctionRateSecuritiesMember" xlink:title="definition: MajorTypesOfDebtAndEquitySecuritiesDomain to AuctionRateSecuritiesMember" use="optional" order="11.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="FairValueByMeasurementFrequencyAxis" xlink:title="FairValueByMeasurementFrequencyAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="FairValueMeasurementFrequencyDomain" xlink:title="FairValueMeasurementFrequencyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByMeasurementFrequencyAxis" xlink:to="FairValueMeasurementFrequencyDomain" xlink:title="definition: FairValueByMeasurementFrequencyAxis to FairValueMeasurementFrequencyDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="FairValueMeasurementFrequencyDomain_2" xlink:title="FairValueMeasurementFrequencyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FairValueByMeasurementFrequencyAxis" xlink:to="FairValueMeasurementFrequencyDomain_2" xlink:title="definition: FairValueByMeasurementFrequencyAxis to FairValueMeasurementFrequencyDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementsRecurringMember" xlink:label="FairValueMeasurementsRecurringMember" xlink:title="FairValueMeasurementsRecurringMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueMeasurementFrequencyDomain" xlink:to="FairValueMeasurementsRecurringMember" xlink:title="definition: FairValueMeasurementFrequencyDomain to FairValueMeasurementsRecurringMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:title="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:title="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="FairValueByMeasurementFrequencyAxis" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable to FairValueByMeasurementFrequencyAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="FairValueByFairValueHierarchyLevelAxis" xlink:title="FairValueByFairValueHierarchyLevelAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="FairValueByFairValueHierarchyLevelAxis" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable to FairValueByFairValueHierarchyLevelAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="FairValueMeasurementsFairValueHierarchyDomain" xlink:title="FairValueMeasurementsFairValueHierarchyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FairValueByFairValueHierarchyLevelAxis" xlink:to="FairValueMeasurementsFairValueHierarchyDomain" xlink:title="definition: FairValueByFairValueHierarchyLevelAxis to FairValueMeasurementsFairValueHierarchyDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="FairValueMeasurementsFairValueHierarchyDomain_2" xlink:title="FairValueMeasurementsFairValueHierarchyDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FairValueByFairValueHierarchyLevelAxis" xlink:to="FairValueMeasurementsFairValueHierarchyDomain_2" xlink:title="definition: FairValueByFairValueHierarchyLevelAxis to FairValueMeasurementsFairValueHierarchyDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="FairValueInputsLevel1Member" xlink:title="FairValueInputsLevel1Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueMeasurementsFairValueHierarchyDomain" xlink:to="FairValueInputsLevel1Member" xlink:title="definition: FairValueMeasurementsFairValueHierarchyDomain to FairValueInputsLevel1Member" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="FairValueInputsLevel2Member" xlink:title="FairValueInputsLevel2Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueMeasurementsFairValueHierarchyDomain" xlink:to="FairValueInputsLevel2Member" xlink:title="definition: FairValueMeasurementsFairValueHierarchyDomain to FairValueInputsLevel2Member" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="FairValueInputsLevel3Member" xlink:title="FairValueInputsLevel3Member" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueMeasurementsFairValueHierarchyDomain" xlink:to="FairValueInputsLevel3Member" xlink:title="definition: FairValueMeasurementsFairValueHierarchyDomain to FairValueInputsLevel3Member" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:label="EstimateOfFairValueFairValueDisclosureMember" xlink:title="EstimateOfFairValueFairValueDisclosureMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueMeasurementsFairValueHierarchyDomain" xlink:to="EstimateOfFairValueFairValueDisclosureMember" xlink:title="definition: FairValueMeasurementsFairValueHierarchyDomain to EstimateOfFairValueFairValueDisclosureMember" use="optional" order="4.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable to MajorTypesOfDebtAndEquitySecuritiesAxis" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:label="CashAndCashEquivalentsFairValueDisclosure" xlink:title="CashAndCashEquivalentsFairValueDisclosure" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="CashAndCashEquivalentsFairValueDisclosure" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to CashAndCashEquivalentsFairValueDisclosure" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ShortTermInvestments" xlink:label="ShortTermInvestments" xlink:title="ShortTermInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="ShortTermInvestments" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to ShortTermInvestments" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecuritiesNoncurrent" xlink:label="AvailableForSaleSecuritiesDebtSecuritiesNoncurrent" xlink:title="AvailableForSaleSecuritiesDebtSecuritiesNoncurrent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="AvailableForSaleSecuritiesDebtSecuritiesNoncurrent" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to AvailableForSaleSecuritiesDebtSecuritiesNoncurrent" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeAssets" xlink:label="DerivativeAssets" xlink:title="DerivativeAssets" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="DerivativeAssets" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to DerivativeAssets" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_OtherAssetsFairValueDisclosure" xlink:label="OtherAssetsFairValueDisclosure" xlink:title="OtherAssetsFairValueDisclosure" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="OtherAssetsFairValueDisclosure" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to OtherAssetsFairValueDisclosure" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AssetsFairValueDisclosure" xlink:label="AssetsFairValueDisclosure" xlink:title="AssetsFairValueDisclosure" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="AssetsFairValueDisclosure" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to AssetsFairValueDisclosure" use="optional" order="7.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeLiabilities" xlink:label="DerivativeLiabilities" xlink:title="DerivativeLiabilities" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="DerivativeLiabilities" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to DerivativeLiabilities" use="optional" order="8.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:label="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:title="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" use="optional" order="9.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosure" xlink:label="LiabilitiesFairValueDisclosure" xlink:title="LiabilitiesFairValueDisclosure" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="LiabilitiesFairValueDisclosure" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to LiabilitiesFairValueDisclosure" use="optional" order="10.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureCommitmentsAndContingenciesDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_OperatingLeasedAssetsLineItems" xlink:label="OperatingLeasedAssetsLineItems" xlink:title="OperatingLeasedAssetsLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfOperatingLeasedAssetsTable" xlink:label="ScheduleOfOperatingLeasedAssetsTable" xlink:title="ScheduleOfOperatingLeasedAssetsTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="OperatingLeasedAssetsLineItems" xlink:to="ScheduleOfOperatingLeasedAssetsTable" xlink:title="definition: OperatingLeasedAssetsLineItems to ScheduleOfOperatingLeasedAssetsTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2013/dei-2013-01-31.xsd#dei_LegalEntityAxis" xlink:label="LegalEntityAxis" xlink:title="LegalEntityAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfOperatingLeasedAssetsTable" xlink:to="LegalEntityAxis" xlink:title="definition: ScheduleOfOperatingLeasedAssetsTable to LegalEntityAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2013/dei-2013-01-31.xsd#dei_EntityDomain" xlink:label="EntityDomain" xlink:title="EntityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="LegalEntityAxis" xlink:to="EntityDomain" xlink:title="definition: LegalEntityAxis to EntityDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2013/dei-2013-01-31.xsd#dei_EntityDomain" xlink:label="EntityDomain_2" xlink:title="EntityDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="LegalEntityAxis" xlink:to="EntityDomain_2" xlink:title="definition: LegalEntityAxis to EntityDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_MaxLinearIncMember" xlink:label="MaxLinearIncMember" xlink:title="MaxLinearIncMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EntityDomain" xlink:to="MaxLinearIncMember" xlink:title="definition: EntityDomain to MaxLinearIncMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_PatentLitigationAbstract" xlink:label="PatentLitigationAbstract" xlink:title="PatentLitigationAbstract" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="OperatingLeasedAssetsLineItems" xlink:to="PatentLitigationAbstract" xlink:title="definition: OperatingLeasedAssetsLineItems to PatentLitigationAbstract" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LossContingencyNumberOfPatentInfringementLawsuitsFiled" xlink:label="LossContingencyNumberOfPatentInfringementLawsuitsFiled" xlink:title="LossContingencyNumberOfPatentInfringementLawsuitsFiled" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PatentLitigationAbstract" xlink:to="LossContingencyNumberOfPatentInfringementLawsuitsFiled" xlink:title="definition: PatentLitigationAbstract to LossContingencyNumberOfPatentInfringementLawsuitsFiled" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LitigationSettlementAmount" xlink:label="LitigationSettlementAmount" xlink:title="LitigationSettlementAmount" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PatentLitigationAbstract" xlink:to="LitigationSettlementAmount" xlink:title="definition: PatentLitigationAbstract to LitigationSettlementAmount" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LossContingencyCovenantPeriod" xlink:label="LossContingencyCovenantPeriod" xlink:title="LossContingencyCovenantPeriod" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PatentLitigationAbstract" xlink:to="LossContingencyCovenantPeriod" xlink:title="definition: PatentLitigationAbstract to LossContingencyCovenantPeriod" use="optional" order="3.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureRisksAndUncertaintiesTables">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskLineItems" xlink:label="ConcentrationRiskLineItems" xlink:title="ConcentrationRiskLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskTable" xlink:label="ConcentrationRiskTable" xlink:title="ConcentrationRiskTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="ConcentrationRiskLineItems" xlink:to="ConcentrationRiskTable" xlink:title="definition: ConcentrationRiskLineItems to ConcentrationRiskTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="ConcentrationRiskByBenchmarkAxis" xlink:title="ConcentrationRiskByBenchmarkAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ConcentrationRiskTable" xlink:to="ConcentrationRiskByBenchmarkAxis" xlink:title="definition: ConcentrationRiskTable to ConcentrationRiskByBenchmarkAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="ConcentrationRiskBenchmarkDomain" xlink:title="ConcentrationRiskBenchmarkDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ConcentrationRiskByBenchmarkAxis" xlink:to="ConcentrationRiskBenchmarkDomain" xlink:title="definition: ConcentrationRiskByBenchmarkAxis to ConcentrationRiskBenchmarkDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="ConcentrationRiskBenchmarkDomain_2" xlink:title="ConcentrationRiskBenchmarkDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ConcentrationRiskByBenchmarkAxis" xlink:to="ConcentrationRiskBenchmarkDomain_2" xlink:title="definition: ConcentrationRiskByBenchmarkAxis to ConcentrationRiskBenchmarkDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccountsReceivableMember" xlink:label="AccountsReceivableMember" xlink:title="AccountsReceivableMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskBenchmarkDomain" xlink:to="AccountsReceivableMember" xlink:title="definition: ConcentrationRiskBenchmarkDomain to AccountsReceivableMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SalesRevenueGoodsNetMember" xlink:label="SalesRevenueGoodsNetMember" xlink:title="SalesRevenueGoodsNetMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskBenchmarkDomain" xlink:to="SalesRevenueGoodsNetMember" xlink:title="definition: ConcentrationRiskBenchmarkDomain to SalesRevenueGoodsNetMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="ConcentrationRiskByTypeAxis" xlink:title="ConcentrationRiskByTypeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ConcentrationRiskTable" xlink:to="ConcentrationRiskByTypeAxis" xlink:title="definition: ConcentrationRiskTable to ConcentrationRiskByTypeAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="ConcentrationRiskTypeDomain" xlink:title="ConcentrationRiskTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ConcentrationRiskByTypeAxis" xlink:to="ConcentrationRiskTypeDomain" xlink:title="definition: ConcentrationRiskByTypeAxis to ConcentrationRiskTypeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="ConcentrationRiskTypeDomain_2" xlink:title="ConcentrationRiskTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ConcentrationRiskByTypeAxis" xlink:to="ConcentrationRiskTypeDomain_2" xlink:title="definition: ConcentrationRiskByTypeAxis to ConcentrationRiskTypeDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CustomerConcentrationRiskMember" xlink:label="CustomerConcentrationRiskMember" xlink:title="CustomerConcentrationRiskMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="CustomerConcentrationRiskMember" xlink:title="definition: ConcentrationRiskTypeDomain to CustomerConcentrationRiskMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SchedulesOfConcentrationOfRiskByRiskFactorTextBlock" xlink:label="SchedulesOfConcentrationOfRiskByRiskFactorTextBlock" xlink:title="SchedulesOfConcentrationOfRiskByRiskFactorTextBlock" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskLineItems" xlink:to="SchedulesOfConcentrationOfRiskByRiskFactorTextBlock" xlink:title="definition: ConcentrationRiskLineItems to SchedulesOfConcentrationOfRiskByRiskFactorTextBlock" use="optional" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureSegmentInformationDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementGeographicalAxis" xlink:label="StatementGeographicalAxis" xlink:title="StatementGeographicalAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="SegmentGeographicalDomain" xlink:title="SegmentGeographicalDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="StatementGeographicalAxis" xlink:to="SegmentGeographicalDomain" xlink:title="definition: StatementGeographicalAxis to SegmentGeographicalDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="SegmentGeographicalDomain_2" xlink:title="SegmentGeographicalDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="StatementGeographicalAxis" xlink:to="SegmentGeographicalDomain_2" xlink:title="definition: StatementGeographicalAxis to SegmentGeographicalDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd#country_SG" xlink:label="SG" xlink:title="SG" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SegmentGeographicalDomain" xlink:to="SG" xlink:title="definition: SegmentGeographicalDomain to SG" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd#country_US" xlink:label="US" xlink:title="US" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SegmentGeographicalDomain" xlink:to="US" xlink:title="definition: SegmentGeographicalDomain to US" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd#country_CN" xlink:label="CN" xlink:title="CN" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SegmentGeographicalDomain" xlink:to="CN" xlink:title="definition: SegmentGeographicalDomain to CN" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd#country_TW" xlink:label="TW" xlink:title="TW" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SegmentGeographicalDomain" xlink:to="TW" xlink:title="definition: SegmentGeographicalDomain to TW" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd#country_JP" xlink:label="JP" xlink:title="JP" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SegmentGeographicalDomain" xlink:to="JP" xlink:title="definition: SegmentGeographicalDomain to JP" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/country/2013/country-2013-01-31.xsd#country_KR" xlink:label="KR" xlink:title="KR" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SegmentGeographicalDomain" xlink:to="KR" xlink:title="definition: SegmentGeographicalDomain to KR" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_OtherCountriesMember" xlink:label="OtherCountriesMember" xlink:title="OtherCountriesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="SegmentGeographicalDomain" xlink:to="OtherCountriesMember" xlink:title="definition: SegmentGeographicalDomain to OtherCountriesMember" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:label="RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:title="RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:label="ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:title="ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:to="ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:title="definition: RevenuesFromExternalCustomersAndLongLivedAssetsLineItems to ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ProductOrServiceAxis" xlink:label="ProductOrServiceAxis" xlink:title="ProductOrServiceAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:to="ProductOrServiceAxis" xlink:title="definition: ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable to ProductOrServiceAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="ProductsAndServicesDomain" xlink:title="ProductsAndServicesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ProductOrServiceAxis" xlink:to="ProductsAndServicesDomain" xlink:title="definition: ProductOrServiceAxis to ProductsAndServicesDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="ProductsAndServicesDomain_2" xlink:title="ProductsAndServicesDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ProductOrServiceAxis" xlink:to="ProductsAndServicesDomain_2" xlink:title="definition: ProductOrServiceAxis to ProductsAndServicesDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BroadBasedSegmentMember" xlink:label="BroadBasedSegmentMember" xlink:title="BroadBasedSegmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="BroadBasedSegmentMember" xlink:title="definition: ProductsAndServicesDomain to BroadBasedSegmentMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_BroadcastSegmentMember" xlink:label="BroadcastSegmentMember" xlink:title="BroadcastSegmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="BroadcastSegmentMember" xlink:title="definition: ProductsAndServicesDomain to BroadcastSegmentMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_AccessSegmentMember" xlink:label="AccessSegmentMember" xlink:title="AccessSegmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ProductsAndServicesDomain" xlink:to="AccessSegmentMember" xlink:title="definition: ProductsAndServicesDomain to AccessSegmentMember" use="optional" order="3.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:to="StatementGeographicalAxis" xlink:title="definition: ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable to StatementGeographicalAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SalesRevenueNet" xlink:label="SalesRevenueNet" xlink:title="SalesRevenueNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:to="SalesRevenueNet" xlink:title="definition: RevenuesFromExternalCustomersAndLongLivedAssetsLineItems to SalesRevenueNet" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="PropertyPlantAndEquipmentNet" xlink:title="PropertyPlantAndEquipmentNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:to="PropertyPlantAndEquipmentNet" xlink:title="definition: RevenuesFromExternalCustomersAndLongLivedAssetsLineItems to PropertyPlantAndEquipmentNet" use="optional" order="3.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureDerivativeFinancialInstrumentsDetails2">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativesFairValueLineItems" xlink:label="DerivativesFairValueLineItems" xlink:title="DerivativesFairValueLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:label="FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:title="FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DerivativesFairValueLineItems" xlink:to="FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:title="definition: DerivativesFairValueLineItems to FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="BalanceSheetLocationAxis" xlink:title="BalanceSheetLocationAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:to="BalanceSheetLocationAxis" xlink:title="definition: FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable to BalanceSheetLocationAxis" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="BalanceSheetLocationDomain" xlink:title="BalanceSheetLocationDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BalanceSheetLocationAxis" xlink:to="BalanceSheetLocationDomain" xlink:title="definition: BalanceSheetLocationAxis to BalanceSheetLocationDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="BalanceSheetLocationDomain_2" xlink:title="BalanceSheetLocationDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="BalanceSheetLocationAxis" xlink:to="BalanceSheetLocationDomain_2" xlink:title="definition: BalanceSheetLocationAxis to BalanceSheetLocationDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_OtherAssetsNetMember" xlink:label="OtherAssetsNetMember" xlink:title="OtherAssetsNetMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BalanceSheetLocationDomain" xlink:to="OtherAssetsNetMember" xlink:title="definition: BalanceSheetLocationDomain to OtherAssetsNetMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LiabilitiesNoncurrentMember" xlink:label="LiabilitiesNoncurrentMember" xlink:title="LiabilitiesNoncurrentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BalanceSheetLocationDomain" xlink:to="LiabilitiesNoncurrentMember" xlink:title="definition: BalanceSheetLocationDomain to LiabilitiesNoncurrentMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InterestRateCashFlowHedgeLiabilityAtFairValue" xlink:label="InterestRateCashFlowHedgeLiabilityAtFairValue" xlink:title="InterestRateCashFlowHedgeLiabilityAtFairValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DerivativesFairValueLineItems" xlink:to="InterestRateCashFlowHedgeLiabilityAtFairValue" xlink:title="definition: DerivativesFairValueLineItems to InterestRateCashFlowHedgeLiabilityAtFairValue" use="optional" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureDerivativeFinancialInstrumentsDetails3">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="IncomeStatementLocationAxis" xlink:title="IncomeStatementLocationAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="IncomeStatementLocationDomain" xlink:title="IncomeStatementLocationDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="IncomeStatementLocationAxis" xlink:to="IncomeStatementLocationDomain" xlink:title="definition: IncomeStatementLocationAxis to IncomeStatementLocationDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_RentExpensesMember" xlink:label="RentExpensesMember" xlink:title="RentExpensesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeStatementLocationDomain" xlink:to="RentExpensesMember" xlink:title="definition: IncomeStatementLocationDomain to RentExpensesMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InterestExpenseMember" xlink:label="InterestExpenseMember" xlink:title="InterestExpenseMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncomeStatementLocationDomain" xlink:to="InterestExpenseMember" xlink:title="definition: IncomeStatementLocationDomain to InterestExpenseMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:label="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:title="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_HedgingRelationshipDomain" xlink:label="HedgingRelationshipDomain" xlink:title="HedgingRelationshipDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:to="HedgingRelationshipDomain" xlink:title="definition: DerivativeInstrumentsGainLossByHedgingRelationshipAxis to HedgingRelationshipDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_HedgingRelationshipDomain" xlink:label="HedgingRelationshipDomain_2" xlink:title="HedgingRelationshipDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:to="HedgingRelationshipDomain_2" xlink:title="definition: DerivativeInstrumentsGainLossByHedgingRelationshipAxis to HedgingRelationshipDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CashFlowHedgingMember" xlink:label="CashFlowHedgingMember" xlink:title="CashFlowHedgingMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="HedgingRelationshipDomain" xlink:to="CashFlowHedgingMember" xlink:title="definition: HedgingRelationshipDomain to CashFlowHedgingMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="DerivativeInstrumentRiskAxis" xlink:title="DerivativeInstrumentRiskAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="DerivativeContractTypeDomain" xlink:title="DerivativeContractTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="DerivativeInstrumentRiskAxis" xlink:to="DerivativeContractTypeDomain" xlink:title="definition: DerivativeInstrumentRiskAxis to DerivativeContractTypeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="DerivativeContractTypeDomain_2" xlink:title="DerivativeContractTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="DerivativeInstrumentRiskAxis" xlink:to="DerivativeContractTypeDomain_2" xlink:title="definition: DerivativeInstrumentRiskAxis to DerivativeContractTypeDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InterestRateSwapMember" xlink:label="InterestRateSwapMember" xlink:title="InterestRateSwapMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DerivativeContractTypeDomain" xlink:to="InterestRateSwapMember" xlink:title="definition: DerivativeContractTypeDomain to InterestRateSwapMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems" xlink:label="DerivativeInstrumentsGainLossLineItems" xlink:title="DerivativeInstrumentsGainLossLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:label="DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:title="DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="DerivativeInstrumentsGainLossLineItems" xlink:to="DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:title="definition: DerivativeInstrumentsGainLossLineItems to DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:to="DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:title="definition: DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable to DerivativeInstrumentsGainLossByHedgingRelationshipAxis" use="optional" order="1.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:to="DerivativeInstrumentRiskAxis" xlink:title="definition: DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable to DerivativeInstrumentRiskAxis" use="optional" order="2.0" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:to="IncomeStatementLocationAxis" xlink:title="definition: DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable to IncomeStatementLocationAxis" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet" xlink:label="DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet" xlink:title="DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DerivativeInstrumentsGainLossLineItems" xlink:to="DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet" xlink:title="definition: DerivativeInstrumentsGainLossLineItems to DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNet" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet" xlink:label="InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet" xlink:title="InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DerivativeInstrumentsGainLossLineItems" xlink:to="InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet" xlink:title="definition: DerivativeInstrumentsGainLossLineItems to InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet" use="optional" order="3.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureBalanceSheetDetailsDetails">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="PropertyPlantAndEquipmentByTypeAxis" xlink:title="PropertyPlantAndEquipmentByTypeAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="PropertyPlantAndEquipmentTypeDomain" xlink:title="PropertyPlantAndEquipmentTypeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="PropertyPlantAndEquipmentByTypeAxis" xlink:to="PropertyPlantAndEquipmentTypeDomain" xlink:title="definition: PropertyPlantAndEquipmentByTypeAxis to PropertyPlantAndEquipmentTypeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_LeaseholdInterestInGroundLeasesMember" xlink:label="LeaseholdInterestInGroundLeasesMember" xlink:title="LeaseholdInterestInGroundLeasesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="LeaseholdInterestInGroundLeasesMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to LeaseholdInterestInGroundLeasesMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BuildingAndBuildingImprovementsMember" xlink:label="BuildingAndBuildingImprovementsMember" xlink:title="BuildingAndBuildingImprovementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="BuildingAndBuildingImprovementsMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to BuildingAndBuildingImprovementsMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EquipmentMember" xlink:label="EquipmentMember" xlink:title="EquipmentMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="EquipmentMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to EquipmentMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_ComputersAndSoftwareMember" xlink:label="ComputersAndSoftwareMember" xlink:title="ComputersAndSoftwareMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="ComputersAndSoftwareMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to ComputersAndSoftwareMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="FurnitureAndFixturesMember" xlink:title="FurnitureAndFixturesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="FurnitureAndFixturesMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to FurnitureAndFixturesMember" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="LeaseholdImprovementsMember" xlink:title="LeaseholdImprovementsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentTypeDomain" xlink:to="LeaseholdImprovementsMember" xlink:title="definition: PropertyPlantAndEquipmentTypeDomain to LeaseholdImprovementsMember" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="PropertyPlantAndEquipmentLineItems" xlink:title="PropertyPlantAndEquipmentLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="ScheduleOfPropertyPlantAndEquipmentTable" xlink:title="ScheduleOfPropertyPlantAndEquipmentTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="PropertyPlantAndEquipmentLineItems" xlink:to="ScheduleOfPropertyPlantAndEquipmentTable" xlink:title="definition: PropertyPlantAndEquipmentLineItems to ScheduleOfPropertyPlantAndEquipmentTable" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfPropertyPlantAndEquipmentTable" xlink:to="PropertyPlantAndEquipmentByTypeAxis" xlink:title="definition: ScheduleOfPropertyPlantAndEquipmentTable to PropertyPlantAndEquipmentByTypeAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="PropertyPlantAndEquipmentGross" xlink:title="PropertyPlantAndEquipmentGross" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentLineItems" xlink:to="PropertyPlantAndEquipmentGross" xlink:title="definition: PropertyPlantAndEquipmentLineItems to PropertyPlantAndEquipmentGross" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:title="AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentLineItems" xlink:to="AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:title="definition: PropertyPlantAndEquipmentLineItems to AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="PropertyPlantAndEquipmentNet" xlink:title="PropertyPlantAndEquipmentNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="PropertyPlantAndEquipmentLineItems" xlink:to="PropertyPlantAndEquipmentNet" xlink:title="definition: PropertyPlantAndEquipmentLineItems to PropertyPlantAndEquipmentNet" use="optional" order="4.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureStockholdersEquityDetails2">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="StatementEquityComponentsAxis" xlink:title="StatementEquityComponentsAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="EquityComponentDomain" xlink:title="EquityComponentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="StatementEquityComponentsAxis" xlink:to="EquityComponentDomain" xlink:title="definition: StatementEquityComponentsAxis to EquityComponentDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:label="AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:title="AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:title="definition: EquityComponentDomain to AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:label="AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:title="AccumulatedNetUnrealizedInvestmentGainLossMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:title="definition: EquityComponentDomain to AccumulatedNetUnrealizedInvestmentGainLossMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:label="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:title="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:label="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:title="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:title="definition: ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems to ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:to="StatementEquityComponentsAxis" xlink:title="definition: ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable to StatementEquityComponentsAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:label="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:title="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:to="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:title="definition: ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable to ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:label="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:title="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:to="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:title="definition: ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis to ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:label="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_2" xlink:title="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:to="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_2" xlink:title="definition: ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis to ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:label="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:title="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:to="ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:title="definition: ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain to ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LeaseAndRentalExpense" xlink:label="LeaseAndRentalExpense" xlink:title="LeaseAndRentalExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="LeaseAndRentalExpense" xlink:title="definition: ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems to LeaseAndRentalExpense" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InterestExpense" xlink:label="InterestExpense" xlink:title="InterestExpense" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="InterestExpense" xlink:title="definition: ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems to InterestExpense" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InvestmentIncomeInterest" xlink:label="InvestmentIncomeInterest" xlink:title="InvestmentIncomeInterest" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="InvestmentIncomeInterest" xlink:title="definition: ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems to InvestmentIncomeInterest" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:title="IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:title="definition: ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems to IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" use="optional" order="5.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="IncomeTaxExpenseBenefit" xlink:title="IncomeTaxExpenseBenefit" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="IncomeTaxExpenseBenefit" xlink:title="definition: ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems to IncomeTaxExpenseBenefit" use="optional" order="6.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="NetIncomeLossAvailableToCommonStockholdersBasic" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="definition: ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems to NetIncomeLossAvailableToCommonStockholdersBasic" use="optional" order="7.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/DisclosureAcquisitionsTables">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EnergyMicroMember" xlink:label="EnergyMicroMember" xlink:title="EnergyMicroMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="EnergyMicroMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to EnergyMicroMember" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_EmberCorporationMember" xlink:label="EmberCorporationMember" xlink:title="EmberCorporationMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="EmberCorporationMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to EmberCorporationMember" use="optional" order="2.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_HeadquartersLeasesMember" xlink:label="HeadquartersLeasesMember" xlink:title="HeadquartersLeasesMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="HeadquartersLeasesMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to HeadquartersLeasesMember" use="optional" order="3.0" />
    <link:loc xlink:type="locator" xlink:href="slab-20131228.xsd#slab_SpectraLinearIncMember" xlink:label="SpectraLinearIncMember" xlink:title="SpectraLinearIncMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="SpectraLinearIncMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to SpectraLinearIncMember" use="optional" order="4.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="BusinessAcquisitionLineItems" xlink:title="BusinessAcquisitionLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="ScheduleOfBusinessAcquisitionsByAcquisitionTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="BusinessAcquisitionLineItems" xlink:to="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="definition: BusinessAcquisitionLineItems to ScheduleOfBusinessAcquisitionsByAcquisitionTable" use="optional" order="1.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to BusinessAcquisitionAxis" use="optional" order="1.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xlink:label="ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xlink:title="ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xlink:title="definition: BusinessAcquisitionLineItems to ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" use="optional" order="2.0" />
  </link:definitionLink>
  <link:definitionLink xlink:type="extended" xlink:role="http://www.silabs.com/role/StatementOfStockholdersEquity">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementLineItems" xlink:label="StatementLineItems" xlink:title="StatementLineItems" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementTable" xlink:label="StatementTable" xlink:title="StatementTable" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="StatementLineItems" xlink:to="StatementTable" xlink:title="definition: StatementLineItems to StatementTable" use="optional" order="10.0" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="StatementEquityComponentsAxis" xlink:title="StatementEquityComponentsAxis" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="StatementTable" xlink:to="StatementEquityComponentsAxis" xlink:title="definition: StatementTable to StatementEquityComponentsAxis" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="EquityComponentDomain" xlink:title="EquityComponentDomain" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="StatementEquityComponentsAxis" xlink:to="EquityComponentDomain" xlink:title="definition: StatementEquityComponentsAxis to EquityComponentDomain" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CommonStockMember" xlink:label="CommonStockMember" xlink:title="CommonStockMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="CommonStockMember" xlink:title="definition: EquityComponentDomain to CommonStockMember" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="AdditionalPaidInCapitalMember" xlink:title="AdditionalPaidInCapitalMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="AdditionalPaidInCapitalMember" xlink:title="definition: EquityComponentDomain to AdditionalPaidInCapitalMember" use="optional" order="20.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="RetainedEarningsMember" xlink:title="RetainedEarningsMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="RetainedEarningsMember" xlink:title="definition: EquityComponentDomain to RetainedEarningsMember" use="optional" order="30.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="AccumulatedOtherComprehensiveIncomeMember" xlink:title="AccumulatedOtherComprehensiveIncomeMember" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="EquityComponentDomain" xlink:to="AccumulatedOtherComprehensiveIncomeMember" xlink:title="definition: EquityComponentDomain to AccumulatedOtherComprehensiveIncomeMember" use="optional" order="40.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="IncreaseDecreaseInStockholdersEquityRollForward" xlink:title="IncreaseDecreaseInStockholdersEquityRollForward" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StatementLineItems" xlink:to="IncreaseDecreaseInStockholdersEquityRollForward" xlink:title="definition: StatementLineItems to IncreaseDecreaseInStockholdersEquityRollForward" use="optional" order="20.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="NetIncomeLossAvailableToCommonStockholdersBasic" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="NetIncomeLossAvailableToCommonStockholdersBasic" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to NetIncomeLossAvailableToCommonStockholdersBasic" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:label="OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:title="OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" use="optional" order="20.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="StockIssuedDuringPeriodValueShareBasedCompensation" xlink:title="StockIssuedDuringPeriodValueShareBasedCompensation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="StockIssuedDuringPeriodValueShareBasedCompensation" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to StockIssuedDuringPeriodValueShareBasedCompensation" use="optional" order="30.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:title="StockIssuedDuringPeriodSharesShareBasedCompensation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StockIssuedDuringPeriodValueShareBasedCompensation" xlink:to="StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:title="definition: StockIssuedDuringPeriodValueShareBasedCompensation to StockIssuedDuringPeriodSharesShareBasedCompensation" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation" xlink:label="AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation" xlink:title="AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation" use="optional" order="8000.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xlink:label="StockRepurchasedAndRetiredDuringPeriodValue" xlink:title="StockRepurchasedAndRetiredDuringPeriodValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="StockRepurchasedAndRetiredDuringPeriodValue" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to StockRepurchasedAndRetiredDuringPeriodValue" use="optional" order="50.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xlink:label="StockRepurchasedAndRetiredDuringPeriodShares" xlink:title="StockRepurchasedAndRetiredDuringPeriodShares" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StockRepurchasedAndRetiredDuringPeriodValue" xlink:to="StockRepurchasedAndRetiredDuringPeriodShares" xlink:title="definition: StockRepurchasedAndRetiredDuringPeriodValue to StockRepurchasedAndRetiredDuringPeriodShares" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:title="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" use="optional" order="60.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions" xlink:label="StockIssuedDuringPeriodValueAcquisitions" xlink:title="StockIssuedDuringPeriodValueAcquisitions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="StockIssuedDuringPeriodValueAcquisitions" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to StockIssuedDuringPeriodValueAcquisitions" use="optional" order="70.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesAcquisitions" xlink:label="StockIssuedDuringPeriodSharesAcquisitions" xlink:title="StockIssuedDuringPeriodSharesAcquisitions" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StockIssuedDuringPeriodValueAcquisitions" xlink:to="StockIssuedDuringPeriodSharesAcquisitions" xlink:title="definition: StockIssuedDuringPeriodValueAcquisitions to StockIssuedDuringPeriodSharesAcquisitions" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="StockholdersEquity" xlink:title="StockholdersEquity" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="StockholdersEquity" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to StockholdersEquity" use="optional" order="80.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="CommonStockSharesOutstanding" xlink:title="CommonStockSharesOutstanding" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="CommonStockSharesOutstanding" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to CommonStockSharesOutstanding" use="optional" order="90.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockholdersEquityPeriodIncreaseDecrease" xlink:label="StockholdersEquityPeriodIncreaseDecrease" xlink:title="StockholdersEquityPeriodIncreaseDecrease" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="StockholdersEquityPeriodIncreaseDecrease" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to StockholdersEquityPeriodIncreaseDecrease" use="optional" order="100.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:label="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:title="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="StockholdersEquityPeriodIncreaseDecrease" xlink:to="StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" xlink:title="definition: StockholdersEquityPeriodIncreaseDecrease to StockIssuedDuringPeriodSharesPeriodIncreaseDecrease" use="optional" order="10.0" />
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet" xlink:label="AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet" xlink:title="AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet" />
    <link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet" xlink:title="definition: IncreaseDecreaseInStockholdersEquityRollForward to AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet" order="40.0" />
  </link:definitionLink>
</link:linkbase>
