RF Micro Devices ( RFMD) blows past its fiscal third-quarter targets, riding a surge in demand for mobile phones.

The Greensboro, N.C., wireless chipmaker shares rose 8% after the company posted adjusted earnings of $34 million, or 16 cents a share. Those numbers compare with a profit of $16 million, or 8 cents a share, in the year-ago period. Analysts were looking for an adjusted profit of 13 cents, according to Reuters Research.

Sales for the quarter ended Dec. 31 were $281 million, up from the $247 million in the prior quarter and above the $208 million revenue level in the year-ago period. Analysts expected fiscal third-quarter revenue of $273 million.

Looking ahead to the end of the current quarter, RF Micro expects seasonal dropoff to be less than usual. The company's guidance for the quarter is for sales somewhere between $250 million and $260 million. That is roughly in line with analysts' consensus of $255 for the quarter.

The company says its pro forma profit will be about 10 cents to 11 cents a share in the fiscal third quarter ending in March. That is in line with the Street's expectation.

"The December 2006 quarter highlights RFMD's ability to drive continued revenue growth and improving profitability," CFO Dean Priddy said in a press release Tuesday. "With our expanded manufacturing capacity, we believe that RFMD is capable of continued revenue growth and reduced manufacturing costs," Priddy continued.

RF Micro shares rose 56 cents to $7.44 in after-hours trading Tuesday.