Output transistor for signalling or amplification in transmission syst - has AND=gate with output linked to transistor base and input connected to load and circuit input to protect against load short circuit

摘要

Transistor is protected against short-circuits at the load, and is controlled at its base by binary signals. It is intended for an electronic signal reproduction circuit in which signalling criteria control the base of a transistor whose collector is connected to a device processing signalling criteria. Output of an AND circuit (N) is connected to the transistor (T) base. AND circuit first input is controlled by binary signal or signalling criteria, and its second input is connected to a circuit (I, R2, C) for inverting and delaying binary signals or signalling criteria. A circuit (D) is inserted between transistor (T) collector and second input of the AND circuit (N) which holds this second input at the potential of one of the binary values ("1") when the transistor (T) is saturated.