CALIFORNIA COURT UPHOLDS JURY VERDICT IN FAVOR OF MONOLITHIC POWER SYSTEMS AGAINST O2 PATENT CLAIMS

SAN JOSE, Calif. October 31, 2007-- Monolithic Power Systems (MPS) (Nasdaq: MPWR), a leading fabless manufacturer of high-performance analog and mixed-signal semiconductors, announced today that the U.S. District Court for the Northern District of California issued a final judgment and rulings affirming the jury verdict entered on May 16, 2007 that all of the patent claims asserted by O2 Micro International (Nasdaq: OIIM) against MPS and MPS’s customer ASUSTeK Computer are invalid. The judgment also found that none of the accused MPS CCFL inverter controllers infringes O2 Micro's patent claims (U.S. patent number 6,396,722).

The company expects that O2 Micro may appeal the case to the U.S. Court of Appeals for the Federal Circuit.

MPS is represented in this case by Cooley Godward & Kronish LLP and Latham & Watkins LLP. MPS's trial counsel includes Mark Flagel, Tom Friel, Jim Brogan, Dean Dunlavey and Matt Brigham.

About Monolithic Power Systems
Monolithic Power Systems, Inc. (MPS) develops and markets proprietary, advanced analog and mixed-signal semiconductors. The company combines advanced process technology with its highly experienced analog designers to produce high-performance power management integrated circuits (ICs) for DC to DC converters, LED drivers, Cold Cathode Fluorescent Lamp (CCFL) backlight controllers, Class D audio amplifiers, and Linear ICs. MPS products are used extensively in computing and network communications products, LCD monitors and TVs, and a wide variety of consumer and portable electronics products. MPS partners with world-class manufacturing organizations to deliver top quality, ultra-compact, high-performance solutions through the most productive, cost-efficient channels. Founded in 1997 and headquartered in San Jose, California, the company has expanded its global presence with sales offices in Taiwan, China, Korea, Japan, and Europe, which operate under MPS International, Ltd.

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