WASHINGTON, March 7 (Reuters) - The U.S. Trade

Representative's Office will hold a hearing on Tuesday into

older Chinese-made "legacy" semiconductors that could heap more

U.S. tariffs on chips from China that power everyday goods from

autos to washing machines to telecoms gear.

The probe, which was started under President Joe Biden in

December, aims to protect American and other semiconductor

producers from China's massive state-driven buildup of domestic

chip supply. A 50% U.S. tariff on Chinese semiconductors started

on Jan. 1.