Control circuit for switching power supply apparatus

Abstract

A control circuit 2a for a switching power supply apparatus includes a comparator COMPa for comparing a voltage corresponding to a current flowing through a switching element PT1 with a voltage to be compared therewith, and outputting a comparison signal corresponding to a result of the comparison. To the comparator, a blanking pulse signal is also input. Here, the blanking pulse signal indicates whether or not it is currently in a predetermined period that is set for ensuring that the switching element is not turned off for the predetermined period after the switching element has been turned on. When the blanking pulse signal indicates that it is currently in the predetermined period, the comparison signal is set to low level independently of the voltage corresponding to the current and the voltage to be compared therewith.

Dependencies are inferred from the claim text.