* Japan stocks expected to take cues from dollar-yen after Yellen - analyst
* Nikon stumbles on wider loss forecast
By Ayai Tomisawa
TOKYO, Feb 14 (Reuters) - Japanese stocks edged down on Tuesday morning, with Toshiba Corp's falling as investors brace for the industrial conglomerate to book a massive multibillion dollar writedown when it reports earnings shortly.
Many investors were also sidelined ahead of Federal Reserve Chair Janet Yellen's semi-annual testimony on policy later in the global day
The Nikkei share average was down 0.1 percent at 19,429.84 in midmorning trade, pulling back from more than one-month highs scaled on the previous day.
Toshiba shares slumped 2.0 percent as investors wait on its earnings at 0300 GMT when the company is set to uncover the scale of a multi-billion dollar writedown from cost overruns at its U.S. nuclear arm, along with a recovery plans as it scrambles for cash.
Exporters were mixed, with Toyota Motor Corp shedding 0.3 percent, Honda Motor Co falling 0.3 percent, and Panasonic Corp rising 0.3 percent.
Yellen is due to present the U.S. central bank's semi-annual report on monetary policy and the economy in testimony to the Senate Banking Committee later in the day, followed by a the semi-annual monetary testimony before the House Financial Committee on Wednesday.
With the Fed's policy path still a key catalyst for global asset markets, Yellen's comments will be closely watched for any further clarity on rate increases over the rest of this year.
Yoshinori Shigemi, global market strategist at JPMorgan Asset Management, said Japanese stocks will likely take cues from the dollar-yen moves, which may be influenced by Yellen's comments.
"Since the Nikkei has recovered from its recent lows, investors started to be cautious about its valuations," Shigemi said.
On Tuesday, the dollar was slightly lower at 113.69 yen , below Monday's high of 114.17 but well above a 10-week low of 111.59 yen touched a week ago.
Nikon Corp dived 13 percent after the company warned of a net loss of 9 billion yen for the year ending March, wider than a loss of 6 billion yen it had expected earlier.
CLSA cut its rating to "sell" from "underperform", saying that it is making progress in restructuring but for a second straight quarter, it cut its guidance for the full year as it has lower expectations for the imaging and instrument segments.
The broader Topix dropped 0.2 percent to 1,441.86 and the JPX-Nikkei Index 400 fell 0.2 percent to 13,914.72.
(Editing by Shri Navaratnam)