Exhibit 99.1

Monolithic Power Systems Announces Third Quarter 2025 Dividend

KIRKLAND, Washington, September 11, 2025 -- Monolithic Power Systems, Inc. (Nasdaq: MPWR), a global company that provides high-performance, semiconductor-based power electronics solutions, announced today its third quarter dividend of $1.56 per common share to all stockholders of record as of the close of business on September 30, 2025. The dividend will be paid on October 15, 2025.

Safe Harbor Statement

This news release includes “forward-looking statements” intended to qualify for the safe harbor from liability established by the Private Securities Litigation Reform Act of 1995. These forward-looking statements are based on our current expectations, estimates and projections about our business and industry, management’s beliefs, and certain assumptions made by us, all of which are subject to change. Forward-looking statements can often be identified by words such as “anticipates,” “expects,” “forecasts,” “intends,” “believes,” “plans,” “may,” “will,” or “continue,” and similar expressions and variations or negatives of these words. All such statements are subject to certain risks, assumptions and uncertainties, including those described in our most recent Annual Report on Form 10-K and Quarterly Reports on Form 10-Qs, and in other documents that we file or furnish with the Securities and Exchange Commission. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially and adversely from those projected, and may affect our future operating results, financial position and cash flows. Accordingly, you are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date they are made. Except to the extent required by law, MPS does not undertake, and expressly disclaims, any duty or obligation to update publicly any forward-looking statement after the initial distribution of this release, whether as a result of new information, future events, changes in assumptions or otherwise.

About Monolithic Power Systems

Monolithic Power Systems, Inc. (“MPS”) is a fabless global company that provides high-performance, semiconductor-based power electronics solutions. MPS’s mission is to reduce energy and material consumption to improve all aspects of quality of life and create a sustainable future. Founded in 1997 by our CEO Michael Hsing, MPS has three core strengths: deep system-level knowledge, strong semiconductor design expertise, and innovative proprietary technologies in the areas of semiconductor processes, system integration, and packaging. These combined advantages enable MPS to deliver reliable, compact, and monolithic solutions that are highly energy-efficient, cost-effective, and environmentally responsible while providing a consistent return on investment to our stockholders. MPS can be contacted through its website at www.monolithicpower.com or its support offices around the world.

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Monolithic Power Systems, MPS, and the MPS logo are registered trademarks of Monolithic Power Systems, Inc. in the U.S. and trademarked in certain other countries.

Contact:

Bernie Blegen

Executive Vice President and Chief Financial Officer

Monolithic Power Systems, Inc.

408-826-0777

MONOLITHIC POWER SYSTEMS INC 8-K