Broadcom sues Microtune over patents

Communications chipmaker Broadcom has sued rival Microtune, alleging that Microtune's power amplifiers, tuners and Bluetooth products violate Broadcom patents.

The lawsuit, announced Monday by Broadcom, marks the latest legal wrangling for the company. The chipmaker is currently a plaintiff or defendant in patent lawsuits involving Intel, National Semiconductor and ST Microelectronics.

"In an economic downturn, many companies choose to tighten down on intellectual property rights," said Sandy Harrison, an analyst with Banc of America Securities. "They attempt to stake out and defend their intellectual property rights, especially if they are losing business to that competitor. In general, we tend see more suits among semiconductor companies in times like these."

The new suit, filed in the U.S. District Court for the Northern District of California, involves Microtune's electrostatic discharge protection circuits and various wireless technologies. It's the third twist in Broadcom's ongoing litigation with Microtune.

Last year, Broadcom filed a patent infringement lawsuit against Microtune in the U.S. District Court for the Eastern District of Texas. The lawsuit, which is expected to go to trial next year, centers on Microtune's solid-state RF tuner products.

A Broadcom representative said the two suits are not related to a patent infringement lawsuit Microtune brought against Broadcom in 2001. That trial, involving a Broadcom TV turner chip, is set to begin March 3.

A Microtune representative said the company would reserve comment on Broadcom's latest lawsuit until its March trial is completed.