Abstract: A bus driver circuit for applying a binary signal to a bus line comprises an input transistor (Q.sub.1) for receiving the signal to be applied to the bus line and an output transistor (Q.sub.2) which taps the signal from the emitter of the input transistor and furnishes its output signal at its collector via a Schottky diode (D.sub.1). Between the base and the collector of the output transistor (Q.sub.2) the collector-emitter path of a transistor (Q.sub.3) is inserted, to the base of which a reference voltage (U.sub.ref) for defining the low value (L) of the binary signal to be applied to the bus line is applied via a Schottky diode (D.sub.3).