Patent ID: 8085022

Claim:
A switching regulator comprising: a power switch circuit including at least one power transistor switch which operates to convert an input voltage to an output voltage; a PWM (Pulse Width Modulation) generation circuit for generating a duty signal in a normal operation mode according to a feedback signal relating to the output voltage; a pulse skipping circuit for calculating On-time in a pulse skipping mode, the On-time being calculated according to a signal from a node with non-constant voltage level, the node being connected with the power transistor switch, wherein the pulse skipping circuit includes: an average circuit for obtaining an average of the signal from the node and outputting a signal proportional to the average; a sawtooth wave generator for generating a sawtooth wave signal according to the signal from the node, wherein the slope of the sawtooth wave signal relates to the input voltage; and a comparator for comparing the output of the average circuit with the sawtooth wave signal to determine the On-time in the pulse skipping mode; and a driver circuit for driving the at least one power transistor switch according to one of the outputs from the PWM generation circuit and the pulse skipping circuit.