DIFFERENTIAL AMPLIFIER

PROBLEM TO BE SOLVED: To provide a differential amplifier that has less non-linear error, has a wide band, and can freely switch a gain. SOLUTION: The differential amplifier 1 includes an input part 11 containing input circuits (Q1, Q2, Q5, Q6, RE1, and RE2) in which a pair of input signals is input and a pair of signals having a difference corresponding to the difference is output, and compensation circuits (Q3 and Q4) which compensate a distortion generated at the input circuit using a pair of signals output from the input circuit, an output part 12 containing a plurality of amplification circuits 12a and 12b in which distortion is compensated by the compensation circuit for the input circuit and a pair of signals output from the input circuit is amplified, and a control circuit 20 for controlling switching of the amplification circuits 12a and 12b, between an amplification circuit which is to be an active state and an amplification circuit which is to be an inactive state. COPYRIGHT: (C)2010,JPO&INPIT