Current switch emitter follower with current mirror coupled push-pull output stage

摘要

Disclosed is a high performance current switch push-pull driver circuit. A first output of the current switch is direct coupled to the push-pull driver while the second output of the current switch is coupled to the push-pull driver by means of an emitter follower and current mirror. Emitter followers connected to the current switch provide a first pair of true/complement outputs while push-pull drivers provide a second set of true/complementary outputs having a higher drive capability. The current mirror is biased near its turn on potential providing current control switching of the current mode transistor and the push-pull driver transistor with which it is coupled. The circuit is greatly tolerant for varying load conditions, is protected against short circuit and power supply failures and has means for three state operation.