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                    <ccc>XXXXXXXX</ccc>
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            <liveTestFlag>LIVE</liveTestFlag>



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            <issuerCik>0001280452</issuerCik>
            <issuerName>MONOLITHIC POWER SYSTEMS, INC.</issuerName>
            <secFileNumber>000-51026</secFileNumber>
            <issuerAddress>
                <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
                <ns2:city>Kirkland</ns2:city>
                <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                <ns2:zipCode>98033</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(425) 296-9956</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>SARIA TSENG</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>1858</noOfUnitsSold>
            <aggregateMarketValue>1532199.70</aggregateMarketValue>
            <noOfUnitsOutstanding>48672000</noOfUnitsOutstanding>
            <approxSaleDate>07/02/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <acquiredDate>11/11/2021</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Shares</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>1858</amountOfSecuritiesAcquired>
            <paymentDate>11/11/2021</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</name>
                <address>
                    <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
                    <ns2:city>Kirkland</ns2:city>
                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/01/2024</saleDate>
            <amountOfSecuritiesSold>2656</amountOfSecuritiesSold>
            <grossProceeds>2168199.04</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</name>
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                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/01/2024</saleDate>
            <amountOfSecuritiesSold>6380</amountOfSecuritiesSold>
            <grossProceeds>5152014.60</grossProceeds>
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                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
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            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/01/2024</saleDate>
            <amountOfSecuritiesSold>1495</amountOfSecuritiesSold>
            <grossProceeds>1206423.44</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</name>
                <address>
                    <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
                    <ns2:city>Kirkland</ns2:city>
                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/01/2024</saleDate>
            <amountOfSecuritiesSold>1758</amountOfSecuritiesSold>
            <grossProceeds>1419349.78</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</name>
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                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
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            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/01/2024</saleDate>
            <amountOfSecuritiesSold>10448</amountOfSecuritiesSold>
            <grossProceeds>8435858.34</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
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                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/01/2024</saleDate>
            <amountOfSecuritiesSold>2099</amountOfSecuritiesSold>
            <grossProceeds>1694619.88</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</name>
                <address>
                    <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
                    <ns2:city>Kirkland</ns2:city>
                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/01/2024</saleDate>
            <amountOfSecuritiesSold>16</amountOfSecuritiesSold>
            <grossProceeds>12911.98</grossProceeds>
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        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</name>
                <address>
                    <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
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                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>07/01/2024</saleDate>
            <amountOfSecuritiesSold>12241</amountOfSecuritiesSold>
            <grossProceeds>9889259.08</grossProceeds>
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        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</name>
                <address>
                    <ns2:street1>5808 Lake Washington Blvd. NE</ns2:street1>
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                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <saleDate>05/08/2024</saleDate>
            <amountOfSecuritiesSold>11</amountOfSecuritiesSold>
            <grossProceeds>7603.90</grossProceeds>
        </securitiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>SARIA TSENG</name>
                <address>
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                    <ns2:stateOrCountry>WA</ns2:stateOrCountry>
                    <ns2:zipCode>98033</ns2:zipCode>
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            <securitiesClassTitle>COMMON</securitiesClassTitle>
            <saleDate>05/08/2024</saleDate>
            <amountOfSecuritiesSold>858</amountOfSecuritiesSold>
            <grossProceeds>592020.00</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>07/02/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>02/29/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Saria Tseng</signature>
        </noticeSignature>
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[{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 10314}]
144
0001312593
XXXXXXXX
LIVE
0001280452
MONOLITHIC POWER SYSTEMS, INC.
000-51026
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
(425) 296-9956
SARIA TSENG
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
1858
1532199.70
48672000
07/02/2024
NASDAQ
COMMON
11/11/2021
Performance Shares
ISSUER
N
1858
11/11/2021
Not Applicable
N
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
07/01/2024
2656
2168199.04
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
07/01/2024
6380
5152014.60
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
07/01/2024
1495
1206423.44
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
07/01/2024
1758
1419349.78
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
07/01/2024
10448
8435858.34
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
07/01/2024
2099
1694619.88
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
07/01/2024
16
12911.98
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
Common
07/01/2024
12241
9889259.08
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
COMMON
05/08/2024
11
7603.90
SARIA TSENG
5808 Lake Washington Blvd. NE
Kirkland
WA
98033
COMMON
05/08/2024
858
592020.00
07/02/2024
02/29/2024
/s/ Saria Tseng