To prevent the malfunction that is caused by external radio waves in an output circuit that uses a PNP type switching transistor.

A collector is connected to the base of a switching transistor Q1, and a 2nd transistor Q2 whose emitter is connected to power supply is provided. An inverted input that inverts a base input to the output transistor Q1 is applied to the base of the 2nd transistor. By doing so, the transistors Q1 and Q2 perform a reverse phase operation. Thus, a malfunction is eliminated because a leakage current to a parasitic capacitor C1 is fed from the transistor Q2 when the transistor Q1 is off.