MPWR Monolithic Power Systems Inc

FORM 4 [ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).         
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES                                                                                   
OMB APPROVAL
OMB Number: 3235-0287
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940                       

1. Name and Address of Reporting Person * Xiao Deming	2. Issuer Name and Ticker or Trading Symbol MONOLITHIC POWER SYSTEMS INC [ MPWR ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                    _____ 10% Owner __X__ Officer (give title below)    _____ Other (specify below) Pres. of MPS Asia Operations
(Last)          (First)          (Middle) 5808 LAKE WASHINGTON BLVD NE	3. Date of Earliest Transaction (MM/DD/YYYY) 7/21/2020
(Street) KIRKLAND, WA 98033 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Performance Shares (1)	(1)	7/21/2020		A (1)		32165		(1)	(1)	Common Stock	32165	$0.0	32165	D

Explanation of Responses:

(1)

On July 21, 2020, the reporting person was granted a target number of 6,433 performance units and can earn up to a maximum of 32,165 performance units subject to satisfaction of share price targets ranging from $260 to $300 over a performance period from July 21, 2020 to July 20, 2023. In addition, all performance units are subject to the achievement of a business operating goal with a performance period through December 31, 2021, as determined by the Compensation Committee of the Company. 75% of the performance units are subject to time-based vesting and require service through July 20, 2023, and the remaining 25% of the performance units are subject to time-based vesting and require service through July 20, 2024. Once vested, the performance units convert into shares of common stock on a 1-for-1 basis and the resulting shares, net of tax withholdings, have a post-vesting sales restriction period of one year.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Xiao Deming 5808 LAKE WASHINGTON BLVD NE KIRKLAND, WA 98033			Pres. of MPS Asia Operations

Signatures
By: Saria Tseng For: Deming Xiao		7/23/2020
**Signature of Reporting Person		Date