SEMICONDUCTOR OUTPUT CIRCUIT

摘要

PURPOSE:To reduce malfunction due to external noise or the like in the semiconductor output circuit which drives an FET using a photo diode optically isolated. CONSTITUTION:A smoothing circuit 5 comprising a diode 7, a capacitor 8 and a resistor 6 and an output section comprising a FET protection diode 9 and a photocoupler 3 are connected between a gate and a source of a FET 2 driven by a photocoupler 1 subjected to optical isolation and the photocoupler 3 is turned on when the FET is turned off. Thus, malfunction due to external noise or the like is reduced in the semiconductor output circuit employing the FET.