Abstract: An operation amplifier 1 for driving an liquid crystal panel is constructed of: differential stage circuits 2, 3, drive stage circuits 4, 5, output transistors 11 to 14, switching means for switching the connections of the differential stage circuits 2, 3 and the drive stage circuits 4, 5, and a middle-potential side power source 10. These differential stage circuits 2, 3 and drive stage circuits 4, 5 are operated between the high-potential side power source 8 and the low-potential side power source 9. The output transistors 11, 12 are operated between the high-potential side power source 8 and the middle-power side power source 10, and also the output transistors 13, 14 are operated between the middle-potential side power source 10 and the low-potential side power source 9, which are alternately driven by the drive stage circuits 4, 5, respectively.