(Corrects to chip maker from handset maker in first paragraph)
* Cirrus offers 235 pence for each Wolfson share
* Says bid supported by 7pct of target's shareholders
* Wolfson shares up more than 70 pct
By Kate Holton
LONDON, April 29 (Reuters) - U.S. chip maker Cirrus Logic Inc is to buy Wolfson Microelectronics Plc for an agreed 291 million pounds ($489 million) in cash, sending shares in the British company up more than 70 percent.
Wolfson, an Edinburgh-based company which specialises in audio technology, had suffered in recent months after missing out on a deal to make chips for the 4G version of Samsung Electronics Co Ltd's Galaxy S4 smartphone.
Wolfson becomes the latest in a series of British technology groups to be bought by overseas interests in recent years, after Autonomy was sold to Hewlett-Packard Co, CGI Group Inc bought Logica and Misys was acquired by U.S.-based private equity firm Vista Equity Partners.
Cirrus, a supplier to Apple Inc, said the agreed 235 pence per share deal for its nearest rival would strengthen its portfolio and add new products such as Wolfson's successful microphones.
Wolfson Chairman Michael Ruettgers said: "Together with Cirrus Logic, we believe this will create a powerful platform for future growth, above and beyond our standalone potential".
Wolfson, which employs around 420 at 12 locations worldwide, also published first-quarter results showing slightly lower than expected revenue.
The group posted an underlying operating loss of $4.5 million, up from $2.8 million a year before, on revenue which slumped to $28.8 million from $48.1 million.
Cirrus said its offer already had the backing of 7 percent of Wolfson's investors.
Analysts at brokerage N+1 Singer said their confidence in Wolfson's technology had not been fully reflected in the financial performance of the company, but said the bid showed the value of its expertise.
"The premium valuation in today's bid reflects the IP (intellectual property) in the product portfolio and the potential which this has in a larger-scale business," they said.
Shares in Wolfson - which dropped to their lowest level in nearly two years in February after the company posted an underlying operating loss of $4.5 million for the final quarter of 2013 - were up 73 percent in early morning trading.
The advance took its stock market value to 270 million pounds.
Dan Ridsdale, analyst at Edison Investment Research, said: Cirrus had got a good deal. "While (Wolfson's) Q1 results were weak as expected, we feel that Cirrus is buying this business at a trading nadir and believe that a recovery in (business) ... primarily at Samsung should drive a strong recovery in H2," Ridsdale said.
In its results statement, Wolfson said it was strengthening its relationship with Samsung with a number of design wins.