Patent ID: 8422259

Claim:
A switch-mode power supply, comprising an apparatus for compensating inductor current peak, a first comparator, a logic control circuit, a driver circuit, a power switch, and an inductor current sensing circuit; wherein when the power switch turns on, the inductor current of the switch-mode power supply flows through the inductor current sensing circuit which provides a sensing voltage; the apparatus for compensating inductor current peak comprises a differential circuit and a compensating network; the differential circuit receives a reference voltage and the sensing voltage as inputs and compares the reference voltage and the sensing voltage to obtain a compensation voltage; the differential circuit stores the compensation voltage and outputs the compensation voltage to the compensating network; the compensating network combines the compensating voltage with the reference voltage and/or the sensing voltage and outputs a combined result to the first comparator; a comparison result of the first comparator is provided to the logic control circuit, an output of the logic control circuit is coupled to a control terminal of the power switch after the output is driven by the drive circuit; the first terminal of the power switch is coupled to the inductor current sensing circuit and the second terminal of the power switch receives the inductor current of the switch-mode power supply as an input.