Symmetricom, the San Jose-based timekeeping technology company with an office in Santa Rosa, is being acquired by Microsemi Corp.

The deal is valued at $230 million, according to a news release by Microsemi, which offers semiconductor and system solutions for communications, defense, security and aerospace markets. Microsemi is based in Aliso Viejo.

The Santa Rosa office of Symmetricom, which once employed more than 100 people, has been downsizing substantially in recent years. Today, only a "couple handful" of sales people remain in the Santa Rosa office, said Tracy Schriver, director of marketing and communications for Symmetricom. The company employs about 500 people, she said.

Details about the acquisition's impact on Symmetricom's employees were not available Thursday.

"We're in the middle of an acquisition so there's not much that we can say," Schriver said.

Symmetricom's timekeeping technologies empower data, voice, mobile, video networks, GPS satellites, national time references and power grids.

The acquisition will enable the companies to offer end-to-end timing solutions for clients, said James J. Peterson, Microsemi president and CEO.

"I believe Microsemi is the ideal company to leverage Symmetricom's technology and capabilities further into the communications market," said Elizabeth Fetter, Symmetricom's CEO, in a statement.

Symmetricom announced major staff reductions in its Santa Rosa office in early 2011, after it outsourced some of its production to another company. That production change resulted in slumping sales because of delayed product shipments.

Symmetricom purchased the Santa Rosa business in 2002 from TrueTime, which was founded in 1972.