To form plural signal output systems without greatly increasing a chip occupation area by providing plural output stages for driving external loads, an amplifier circuit for driving a plurality of output stages and a current switch for selectively setting the plurality of output stages into an operation state in accordance with a switch control signal.

The output means 100 and 200 drive the corresponding external loads. An operational amplifier circuit A1 dives the output stages 100 and 200 based on an inputted signal. MOS transistors M3, M5, M6 and M8 selectively set the output stages 100 and 200 in an operation state in accordance with the switch control signal. Since the operational amplifier circuit A1 for driving the output means 100 and 200 is shared by the output stages 100 and 200 with such means, a chip occupation area can be reduced compared to a case when private operational amplifiers for driving the output stages are provided for the respective output stages 100 and 200.