UPDATE 2-Volterra Q3 earnings rise; gives Q4 view

* Earnings of $0.25/shr meets analysts' estimates

* Revenue rises 62 percent to $30.6 mln

* Gross margin rises 72 percent to $17.7 mln

* Sees Q4 EPS at $0.16-$0.24; rev $26 mln-$30 mln (Adds outlook from conference call, share movement)

Oct 20 (Reuters) - Volterra Semiconductor Corp (VLTR.O), a low-voltage power supply chipmaker, posted higher third-quarter earnings, which was in line with analysts' expectations, helped by a 72 percent jump in gross margins.

In a conference call with analysts, the company forecast fourth-quarter earnings of 16 cents to 24 cents per share, before items, on revenue of $26 million to $30 million.

Analysts on average were expecting earnings of 24 cents a share, before items, on revenue of $30.34 million, according to Reuters Estimates.

For the latest third quarter, Volterra posted earnings of $5.4 million, or 21 cents a share for the quarter ended Sept. 30, compared with 497,000, or 2 cents a share, a year earlier.

Excluding items, Volterra earned 25 cents per share, while revenue rose 62 percent to $30.6 million.

Analysts on average had expected a profit of 25 cents a share, before items, on revenue of $30 million.

Shares of the Fremont, California-based company rose more than 4 percent to $9.80 in trading after the bell Monday. They closed at $9.40 on Nasdaq. (Reporting by Bijoy Koyitty in Bangalore; Editing by Vinu Pilakkott, Gopakumar Warrier)