-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001246948-03-000017.txt : 20031030
<SEC-HEADER>0001246948-03-000017.hdr.sgml : 20031030
<ACCEPTANCE-DATETIME>20031030113155
ACCESSION NUMBER:		0001246948-03-000017
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031028
FILED AS OF DATE:		20031030

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SILICON LABORATORIES INC
		CENTRAL INDEX KEY:			0001038074
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				742793174
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4635 BOSTON LN
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78735

	MAIL ADDRESS:	
		STREET 1:		4635 BOSTON LANE
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78735

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BRENNAN RUSSELL J
		CENTRAL INDEX KEY:			0001198394

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-29823
		FILM NUMBER:		03965666

	BUSINESS ADDRESS:	
		STREET 1:		4635 BOSTON LANE
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78735
		BUSINESS PHONE:		5124168500
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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        <issuerName>SILICON LABORATORIES INC</issuerName>
        <issuerTradingSymbol>SLAB</issuerTradingSymbol>
    </issuer>

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            <rptOwnerName>BRENNAN RUSSELL J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>4635 BOSTON LANE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>AUSTIN</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>78735</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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            <transactionAmounts>
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                <transactionFormType>4</transactionFormType>
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            </securityTitle>
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            <transactionDate>
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                </underlyingSecurityTitle>
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            <securityTitle>
                <value>Non-Qualified Stock Option (right to buy)</value>
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    </derivativeTable>

    <footnotes>
        <footnote id="F1">Option first became exercisable on September 12, 2003.  Option vests and becomes exercisable over a 60-month period with respect to (i) twenty percent (20%) of the option shares vest and become exercisable upon optionee's completion of one year of service measured from September 12, 2002 and (ii) the balance of the option shares vest and become exercisable in a series of forty-eight (48) successive equal monthly installments over the forty-eight (48) month period measured from the first year anniversary of September 12, 2002.</footnote>
        <footnote id="F2">Not applicable per instruction 4(c)(iii).</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>Russell J. Brennan</signatureName>
        <signatureDate>2003-10-30</signatureDate>
    </ownerSignature>

</ownershipDocument>

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</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----