Patent ID: 7193425

Claim:
A semiconductor test device for switching a driver output between one of a plurality of voltages and a higher voltage that is higher than the highest voltage of said plurality of voltages and outputting said driver output to test a device under test, comprising: a first buffer portion operable to output said plurality of voltages by a push-pull circuit of an emitter follower serving as a source and an emitter follower serving as a sink; a second buffer portion operable to output said higher voltage by a push-pull circuit of said emitter follower serving as said sink of said first buffer portion and an emitter follower serving as a source of said higher voltage; and a switching means for switching which one of the emitter follower serving as a source in the first buffer and the emitter follower serving as a source in the second buffer serves as a source to form the push-pull circuit together with said emitter follower serving as said sink of said first buffer portion.