Bicmos integrated circuit device utilizing schottky diodes

Abstract

The invention relates to a BiCMOS or bipolar/CMOS hybrid integrated circuit device which has both bipolar transistors and MOS transistors on the same semiconductor substrate. An output circuit of the device having a push-pull configuration is constructed of two bipolar transistors Darlington-connected with each other arranged at the upper push-side and a MOS transistor arranged at the lower pull-side. A Schottky diode is interposed between the power supply line and the Darlington-connected bipolar transistors, thereby preventing the flow of currents from an output node into the output circuit. The output circuit also includes a clamping circuit of a Schottky diode for preventing the output bipolar transistor from being saturated and, a discharging circuit of a Schottky diode and a resistor connected in series, for discharging the charges stored in the base of the same bipolar transistor. The output circuit is simple in its construction as compared with the conventional ones and can readily be connected to or disconnected from, for example, a bus line even when the bus line is in an active state.