PURPOSE: To provide the CMOS comparator with small circuit configuration, low power consumption and high accuracy with respect to the differential chopper type CMOS comparator.

CONSTITUTION: A reset operation or a comparison operation is selected in the differential chopper type CMOS comparator, which compares the quantity between an input voltage Vin and a reference voltage Vref. An offset correction circuit 21 is coupled with the differential chopper type CMOS comparator by a current mirror circuit and an offset of the differential chopper type CMOS comparator is stored by the reset operation and the offset is cancelled in the comparison operation to correct the output of the differential chopper type CMOS comparator. A strobe latch circuit 22 latches a voltage at a high/low level corresponding to the quantity between the input voltage Vin and the reference voltage Vref in response to a change in an output current of the offset correction circuit 21.