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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001413753-08-000020.txt : 20080303
<SEC-HEADER>0001413753-08-000020.hdr.sgml : 20080303
<ACCEPTANCE-DATETIME>20080303181616
ACCESSION NUMBER:		0001413753-08-000020
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20080228
FILED AS OF DATE:		20080303
DATE AS OF CHANGE:		20080303

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DANTEC ALAIN
		CENTRAL INDEX KEY:			0001336929

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-06395
		FILM NUMBER:		08661140

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		805 498 2111

	MAIL ADDRESS:	
		STREET 1:		200 FLYNN ROAD
		CITY:			CAMARILLO
		STATE:			CA
		ZIP:			93012-8790

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SEMTECH CORP
		CENTRAL INDEX KEY:			0000088941
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				952119684
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0127

	BUSINESS ADDRESS:	
		STREET 1:		200 FLYNN ROAD
		CITY:			CAMARILLO
		STATE:			CA
		ZIP:			93012-8790
		BUSINESS PHONE:		8054982111

	MAIL ADDRESS:	
		STREET 1:		200 FLYNN ROAD
		CITY:			CAMARILLO
		STATE:			CA
		ZIP:			93012-8790
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-02-28</periodOfReport>

    <issuer>
        <issuerCik>0000088941</issuerCik>
        <issuerName>SEMTECH CORP</issuerName>
        <issuerTradingSymbol>SMTC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001336929</rptOwnerCik>
            <rptOwnerName>DANTEC ALAIN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 FLYNN ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CAMARILLO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>93012-8790</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-02-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>12500</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>35000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>13.15</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-02-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>25000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2019-02-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>25000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>25000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">This is restricted stock that vests in three approximately equal annual installments beginning on February 28, 2009</footnote>
        <footnote id="F2">This option vests in three approximately equal annual installments beginning on February 28, 2009</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Alain Dantec by Drew L. Alexis under Power of Attorney dated January 23, 2008 (copy attached)</signatureName>
        <signatureDate>2008-03-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>attach_1.htm
<DESCRIPTION>ALAIN DANTEC POWER OF ATTORNEY DATED JANUARY 23, 2008
<TEXT>
<HTML><BODY><PRE>POWER OF ATTORNEY



The undersigned, Alain Dantec, hereby constitutes and

appoints Emeka Chukwu, Suzanna Fabos and Drew L. Alexis, each of them,

jointly and severally, his lawful attorney in fact and agent,

with full power of substitution and resubstitution, for him

and in his name, place and stead, in any and all capacities,

to execute and file with the Securities and Exchange Commission

and any stock exchange or similar authority (or any other

governmental or regulatory authority) Forms ID, 3, 4 and 5 under

Section 16(a) of the Securities Exchange Act of 1934, as amended

(the Act) and the rules thereunder, or any other appropriate

form, and all amendments thereto with all exhibits and any and

all documents required to be filed with respect thereto, relating

to his holdings or beneficial ownership of securities issued by

Semtech Corporation, a corporation organized under the laws of

the State of Delaware (the Corporation), granting unto said

attorneys in fact and agents, and each of them, full power and

authority to do and perform each and every act and thing requisite

or necessary to be done as fully to all intents and purposes as

he might or could do in person, hereby ratifying and confirming

all that said attorneys in fact and agents, and each of them, or

his substitute or substitutes, may do or lawfully cause to

be done by virtue hereof.



The undersigned acknowledges that the foregoing attorneys in fact

and agents, solely by virtue of serving in such capacity at the

request of the undersigned, are not assuming, nor is the Corporation

assuming, any of the undersigneds responsibilities to comply with

Section 16 of the Act.



This Power of Attorney shall remain in full force and effect until

the undersigned is no longer required to file Forms ID, 3, 4 and 5 with

respect to the undersigneds holdings or beneficial ownership of

and transactions in securities issued by the Corporation, unless

earlier revoked by the undersigned in a writing delivered to the

foregoing attorneys in fact.





/s/ Alain Dantec

January 23, 2008

</PRE></BODY></HTML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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