PURPOSE: To accelerate a complementary MISFET comparator circuit without deteriorating the characteristics of in-phase component removing ratio by reducing the voltage amplitude of an output stage with an MISFET element.

CONSTITUTION: A differential amplifier of difference inputting single-ended output is composed of MISFET M11∼M15. A driver MISFET M16 and a load MISFET M17 form an output stage inverting amplifier, and a source-grounded MISFET M18 in which a gate electrode is connected to a constant-voltage source Vb12 and a drain electrode is connected to a comparator output terminal in the same conductivity type channel as the MISFET M16 is added thereto. Thus, even if its input voltage amplitude is large and the MISFET M16 becomes high resistance, the output voltage of the comparator is not fluctuated. Accordingly, the output voltage amplitude is small and the input comparison can be performed more rapidly.