* Expects first-quarter rev $645-$685 mln vs est $663.8 mln
* Fourth-quarter adj earnings $0.08/share vs est $0.07
* Fourth-quarter revenue $680.2 mln vs $671.2 mln
Feb 7 (Reuters) - ON Semiconductor Corp, a maker of power-management chips, reported quarterly revenue above analysts' estimates and forecast current-quarter sales largely above market expectations as it anticipates a rebound in demand.
The company expects first-quarter revenue of $645 million to $685 million, while analysts are expecting $663.8 million, according to Thomson Reuters.
ON Semiconductor said new design wins and increasingly lean inventory levels at customers and distributors suggests that it was seeing the bottom of the down cycle.
"Backlog levels for the first quarter of 2013 represent about 80 percent to 85 percent of our anticipated first-quarter 2013 revenue," Chief Executive Keith Jackson said in a statement.
The company, which makes radio-frequency custom chips for consumer, automotive and industrial markets, struggled with weak demand throughout last year, after floods in Thailand in late 2011 affected production as well as demand from customers.
ON Semiconductor counts Flextronics, Samsung Electronics Co Ltd, Sony Corp and Panasonic Corp among its customers.
Fourth-quarter net loss attributable to the company widened to $138.2 million, or 31 cents per share, from $8.8 million, or 2 cents per share, a year earlier.
The bigger loss was mainly due to lower orders from its customers and asset-impairment charges stemming from its Sanyo Semiconductor business.
The company, which has been trying to turn around the loss-making Sanyo unit that it acquired in January 2011, took a $150.4 million non-cash asset impairment charge related to the unit in the fourth quarter.
The Sanyo unit designs, manufactures and sells radio frequency and power-related components used in flash memory devices and touch sensors.
"In 2013, we will continue to take additional actions at our SANYO Semiconductor Products Group to reduce the break-even level and return this operating segment to profitability," Jackson said.
The company cut about 250 jobs and canceled annual cash bonuses for senior executives in August to reduce costs.
Excluding charges, the company earned 8 cents per share.
Fourth-quarter revenue fell 11 percent to $680.2 million.
Analysts expected adjusted earnings of 7 cents per share, on revenue of $671.2 million.
The Phoenix, Arizona-based company's shares were down 1 percent at $8.10 before the bell. They closed at $8.19 on the Nasdaq on Wednesday.