Inverter switch stage using bipolar transistor totem-pole circuit - has controlled current source FET supplying current to base of bipolar transistor when transistor is conductive, and preventing current when transistor is off, to provide TTL output.

摘要

The inverter switch stage has 2 series bipolar transistors (1,2) between 2 supply potentials (VCC,VEE), the collector/base path of each transistor lying in parallel with the drain/source path of a respective complementary MOSFET (3,4). The input terminal (8) is coupled to both MOSFET gates and the output terminal (7) is coupled to the junction between the emitter of the first bipolar transistor and the collector of the second bipolar transistor. A controlled current source is coupled between the base of the second bipolar transistor and a fixed potential (VI) for providing a current only when the bipolar transistor is conductive.