OPERATIONAL AMPLIFIER

PROBLEM TO BE SOLVED: To prevent increase in current consumption, and to improve the frequency characteristics of a circuit. SOLUTION: In an operational amplifier having transistors Q9, Q10 whose collectors are commonly connected to an output terminal 13; a transconductance amplifier A1 which is connected to input terminals 11, 12; a transistor Q3 which determines the base current of the transistor Q10 in proportion to the non-inversion side output current of the transconductance amplifier A1; and a transistor Q5, which determines base current of the transistor Q9 in proportion to inversion side output current of the transconductance amplifier A1, by determining the suction amount of a current from a current source I2, in proportion to the collector current of the transistor Q3; the current source I2 is replaced by a transistor Q6, which determines collector current in proportion to the inverting side output current of the transconductance amplifier A1. COPYRIGHT: (C)2011,JPO&INPIT