* Q3 adj shr $0.67 beats est by $0.07
* Q3 rev $125.9 mln vs est $123.8 mln
* Sees Q4 adj shr $0.60-$0.63 vs est $0.60
* Sees Q4 rev $124-$129 mln vs est $126.3 mln
* CEO says looking to buy private firms (Adds CEO comments, share buyback, updates stock movement)
By Sudipto Ganguly
BANGALORE, Oct 28 (Reuters) - Silicon Laboratories (SLAB.O) posted better-than-expected quarterly results helped by strong demand for its FM radio tuner chips, especially for handsets made by a key customer, Samsung (005930.KS).
Silicon Laboratories also forecast fourth-quarter results in line with Wall Street expectations, reflecting the expected moderation in demand in the current quarter at Samsung. [ID:nBNG533420]
The expected fall in demand at Samsung was the main reason for the forecasted sequential fall in its radio frequency (RF) chips sales in the current fourth quarter, Chief Executive Necip Sayiner told Reuters in an interview.
However, in the third quarter, revenue soared at five out of its eight product lines -- audio, video, short-range wireless, timing and micro-controllers -- led by a 40 percent surge in its RF business.
"These five product lines along with the power business will continue to support our growth in the near future," Sayiner told Reuters.
The company, whose competitors include Texas Instruments TXI.N, Analog Devices ADI.N and Broadcom (BRCM.O), was also looking at strategic acquisition opportunities, he said.
"We're primarily looking at the late stage private companies that we can help grow faster, than they can on their own, Sayiner told Reuters.
The company, whose customers also include Huawei [HWT.UL], LG Electronics (066570.KS) and Motorola MOT.N, also said it will buy back up to $150 million shares through the end of 2010.
Third-quarter profit rocketed to $22.4 million, or 47 cents a share, from $1.2 million, or 2 cents a share, a year ago.
Adjusted earnings and revenue both came in ahead of Wall Street expectations. [ID:nWNAB5665]
For the fourth quarter, the company expects adjusted earnings of 60 cents to 63 cents a share, on revenue of $124 million to $129 million.
Analysts were expecting earnings of 60 cents, on revenue of $126.3 million, according to Thomson Reuters I/B/E/S.
Shares of the Austin, Texas-based company rose about 4 percent, before paring some of those gains to trade up 42 cents at $41.80 in afternoon trade on Nasdaq. (Reporting by Sudipto Ganguly in Bangalore; Editing by Ratul Ray Chaudhuri and Savio D'Souza)