DIFFERENTIAL AMPLIFIER

PROBLEM TO BE SOLVED: To provide a differential amplifier from which an output signal without distortion is obtained regardless of a wide input voltage range. SOLUTION: Two differential input circuits 111, 112 are made up of MOS transistors(TRs) 1111 , 1112 , 1121 , and 1122 , one of the differential input circuits is directly connected to an inverting input terminal 116 and a noninverting input terminal 117 and the other differential input circuit connects to the inverting input terminal 116 and the noninverting input terminal 117 via level shift circuits 120a, 120b. The differential amplifier amplifies an input voltage with a range from a ground level to a power supply voltage and the electric characteristic of the two differential input circuits 111, 112 is identical to each other, then no distortion is caused in an output signal. A current control circuit connects to each of the differential input circuits 111,112 and when the control circuit cannot be normally operated, no current is supplied.