A differential circuit includes a differential pair and a back gate bias circuit. The differential circuit includes a first MOS transistor and a second MOS transistor provided between a first power supply line, to which a first power supply voltage is applied, and a second power supply line, to which a second power supply voltage is applied. The back gate bias circuit applies a bias voltage closer to the first power supply voltage than source potentials of the first MOS transistor and the second MOS transistor to back gates of the first MOS transistor and the second MOS transistor.