Comparator circuit, power supply control ic, and switching power supply device

An offset correction method for a comparator circuit including

• a first comparator arranged to compare an input signal with a reference voltage so as to generate a first comparison signal and
• a second comparator arranged to compare the input signal with a variable reference voltage so as to generate a second comparison signal,
• a response speed of the first comparator being faster than a response speed of the second comparator,
• a power consumption of the second comparator being smaller than a power consumption of the first comparator,
• the method comprising:
• while outputting the first comparison signal as a comparison signal, sweeping the variable reference voltage until, before a logic level of the first comparison signal switches, a logic level of the second comparison signal switches as a result of the second comparator responding earlier than the first comparator to the variable reference voltage crossing the reference voltage;
• and
• after completing sweeping of the variable reference voltage, moving to a state where the second comparison signal can be output as the comparison signal.