Emitter drive: a technique to drive a bipolar power transistor switching at 100 kHz

Abstract

Theoretical support and experimental results concerning the application of an emitter driven bipolar power transistor to a 400 V 10 A power switch are presented. The central idea of the emitter drive is to turn off and on the bipolar transistor controlling the flow of the emitter current, using another switch. This switch was implemented with a low voltage power MOSFET. In this way it is possible to achieve a power switch with fairly high voltage rating, without excessive forward voltage drop (not achievable using power MOSFETS), and greater speed than by means of a bipolar transistor using the traditional base drive.<>