    <SEC-DOCUMENT>0001437749-22-024940-index.html : 20221027
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    <ACCEPTANCE-DATETIME>20221027160124
    ACCESSION NUMBER:		0001437749-22-024940
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		28
    CONFORMED PERIOD OF REPORT:	20221027
    ITEM INFORMATION:		Results of Operations and Financial Condition
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20221027
    DATE AS OF CHANGE:		20221027

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			MONOLITHIC POWER SYSTEMS INC
    		CENTRAL INDEX KEY:			0001280452
    		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
    		IRS NUMBER:				770466789
    		STATE OF INCORPORATION:			DE
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-51026
    		FILM NUMBER:		221337270

    	BUSINESS ADDRESS:
    		STREET 1:		5808 LAKE WASHINGTON BLVD. NE
    		CITY:			KIRKLAND
    		STATE:			WA
    		ZIP:			98033
    		BUSINESS PHONE:		425-296-9956

    	MAIL ADDRESS:
    		STREET 1:		5808 LAKE WASHINGTON BLVD. NE
    		CITY:			KIRKLAND
    		STATE:			WA
    		ZIP:			98033
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    <FILENAME>mpwr-20221027.xsd
    <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA
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    <FILENAME>Financial_Report.xlsx
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