Microsemi Corp., a Santa Ana-based semiconductor firm, signed an agreement Wednesday to acquire Linfinity Microelectronics Inc. of Garden Grove from Symmetricom Corp. in a $24.13-million cash deal. Symmetricom said it expected to report a net after-tax loss of as much as $4 million, or 26 cents a share, from the deal, expected to close next month. Microsemi said the deal helps secure a strategic partnership with Linfinity, which makes integrated circuits that manage the power used by consumer electronics. The firm has about 220 employees. No layoffs are expected. Microsemi stock fell 44 cents to close at $11.06. Symmetricom stock was down 6 cents to $7.88, both on Nasdaq.