Toshiba Corp has received bids ranging from 200 billion yen to as much as 400 billion yen ($1.8-3.6 billion) for a 19.9 percent stake in its flash memory business, a person directly involved in the deal told Reuters on Thursday. A sale at that price would help Toshiba offset a multi-billion dollar writedown on its U.S. nuclear power business, which investors worry could wipe out shareholder equity. Suitors for the Japanese company's chip unit include rivals SK Hynix Inc and Micron Technology Inc, data storage firm Western Digital Corp and financial investors such as Bain Capital, people told Reuters earlier this week.