PURPOSE: To reduce power consumption by controlling the output point of an inverter for which a 1st power supply formed by P and N transistors(TRs) controlled by an output from an input signal circuit is supplied through an output level setting circuit for which a 2nd power supply is supplied.

CONSTITUTION: A 1st inverter 61 formed by PTRs 21, 22 and an NTR 23 connected in series is driven by the 1st power supply EVLC such as 3V, a 2nd inverter 62 similar to the inverter 61 is also similarly driven and one 29 of the output points of these inverters 61, 62 is connected to an output terminal Sout. On the other hand, the output points 28, 29 are controlled by an output level setting circuit 32 driven by the 2nd power supply of 2V, e.g. and when an input signal from an input signal terminal SIN to the circuit 32 driven by a power supply VDD falls from 'H' to 'L', the potential of the input points 28, 29 is turned to the potential of the power supply VDD for a short time and current formig into the inverter circuits is reduced to reduce power consumption. When the input signal turns from 'L' to 'H', a similar result can be obtained.