A state wherein offset voltage is reduced can be maintained regardless of environmental fluctuation. A differential amplification unit has differential pair transistors, and amplifies a difference between input voltages. An offset voltage measurement unit samples offset voltage generated due to an imbalance in the current drive capacities of the differential pair transistors in a first mode, and determines the polarity of the sampled offset voltage in a second mode. A control unit switches the operating mode between the first mode and second mode, and outputs a control signal for correcting the offset voltage in accordance with the polarity determination result when in the second mode. An offset voltage correction unit corrects the offset voltage based on the control signal.