A senior human resources manager at Toshiba has filed a $100 million lawsuit accusing a U.S. unit of the Japanese technology company of gender bias against women in pay and promotions.

The plaintiff, Elaine Cyphers, contends that Toshiba America pays women lower salaries and bonuses than men who perform similar work. She alleges the company steers women into lower-grade positions and favors men in promotions.

She said this results in an "astounding lack of women in leadership positions," despite Toshiba's creation six years ago of a "Gender Equality Office."

Toshiba spokesman Tom Gallatin in an email said the company generally does not discuss pending litigation.

A lawyer for Cyphers did not immediately return a request for comment.

Cyphers said she has been human resources manager at Toshiba America Nuclear Energy and the highest-ranking U.S. human resources employee at that unit. She said she was paid $90,000 to $91,800 a year between 2008 and 2010, while men in similar jobs at Toshiba were paid about $120,000 annually.

The lawsuit is the latest of many accusing companies of favoring men over women in the workplace. It seeks class-action status on behalf of all current and former Toshiba female employees in the United States. Cyphers said she also filed a complaint with the Equal Employment Opportunity Commission.

Last July, Novartis agreed to pay $175 million to settle a class-action lawsuit accusing the Swiss drugmaker of discriminating against 5,600 women sales representatives in pay and promotions. A lawyer representing Cyphers was involved in that case.

The U.S. Supreme Court is expected to decide by June whether Wal-Mart must continue to defend against the largest U.S. class-action gender bias lawsuit in history, brought on behalf of as many as 1.5 million current and former female employees.

Cyphers said she had worked in human resources for 25 years before Toshiba hired her in June 2008, and moved about 110 miles to Falls Church, Va., for the job.

She said Toshiba soon promoted a less-experienced man to a new position above her, and later sought to force her from the company in retaliation for complaints about discrimination.

When Cyphers returned last month from medical leave, a supervisor told her to leave and not to return "until further notice," so she "promptly collected her belongings" and left, the complaint said. She now lives in North Carolina, it added.

The case is Cyphers v. Toshiba America Inc et al, U.S. District Court, Southern District of New York, No. 11-00642.