-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 H4AYTza1il4nqnPKYEfVlM5m2CcQu15y9mIgjMSCdzyJUgANYy5jldOa2YI3tmnO
 8uXKvCjOwcKa5t3+b6u89A==

<SEC-DOCUMENT>0000791907-09-000025.txt : 20090227
<SEC-HEADER>0000791907-09-000025.hdr.sgml : 20090227
<ACCEPTANCE-DATETIME>20090227142429
ACCESSION NUMBER:		0000791907-09-000025
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090226
FILED AS OF DATE:		20090227
DATE AS OF CHANGE:		20090227

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SWANSON ROBERT H JR
		CENTRAL INDEX KEY:			0001253580

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14864
		FILM NUMBER:		09641744

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		4084321900 X2412

	MAIL ADDRESS:	
		STREET 1:		1630 MCCARTHY BLVD
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LINEAR TECHNOLOGY CORP /CA/
		CENTRAL INDEX KEY:			0000791907
		STANDARD INDUSTRIAL CLASSIFICATION:	SEMICONDUCTORS & RELATED DEVICES [3674]
		IRS NUMBER:				942778785
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0703

	BUSINESS ADDRESS:	
		STREET 1:		1630 MCCARTHY BLVD
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035
		BUSINESS PHONE:		4084321900

	MAIL ADDRESS:	
		STREET 1:		1630 MCCARTHY BLVD
		CITY:			MILPITAS
		STATE:			CA
		ZIP:			95035
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-02-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000791907</issuerCik>
        <issuerName>LINEAR TECHNOLOGY CORP /CA/</issuerName>
        <issuerTradingSymbol>LLTC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001253580</rptOwnerCik>
            <rptOwnerName>SWANSON ROBERT H JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1630 MCCARTHY BLVD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MILPITAS</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95035</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Executive Chairman</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>3.125% Convertible Senior Note</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>50.47</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-02-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionTotalValue>
                    <value>2000000</value>
                </transactionTotalValue>
                <transactionPricePerShare>
                    <value>1890000</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2027-05-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityValue>
                    <value>2000000</value>
                </underlyingSecurityValue>
            </underlyingSecurity>
            <postTransactionAmounts>
                <valueOwnedFollowingTransaction>
                    <value>2000000</value>
                </valueOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Exercisable as of transaction date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Robert H. Swanson, Jr.</signatureName>
        <signatureDate>2009-02-27</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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