PURPOSE: To perform high-speed operation by supplying a driving stage with a power voltage higher than the power voltage of a final stage which has a capacitive load.

CONSTITUTION: When an input signal is applied to a terminal 16, MOS transistors (TR) 12 and 13 turn on and an MOSTR 14 turns off. A capacitive load 15 is therefore driven at a power voltage VDD2. When the input signal is ceased, the TRs 12 and 13 turn off and a power voltage VDD1 higher than a power voltage VDD2 is applied to the gate of the TR14. Consequently, the TR14 turns on speedily to charge the capacitive load 15 abruptly.