Patent ID: 8068354

Claim:
A current-level controlling device for a power supply comprising: a reception end for receiving a current sense signal; a reference voltage generator for generating a reference voltage; an adaptive reference voltage generator, coupled to the reference voltage generator and the reception end, for adjusting the reference voltage according to variation of peak values of the current sense signal, so as to generate an adaptive reference voltage, comprising: a peak current detector, coupled to the reception end, for detecting variation of the peak values of the current sense signal, comprising: a transistor, comprising a first end coupled to a voltage source, a second end and a third end, for conducting a signal connection between the first end and the third end according to signals received by the second end; an operational amplifier, comprising a first input end coupled to the reception end, a second input end coupled to the third end of the transistor, and an output end coupled to the second end of the transistor; and a capacitor, having one end coupled between the third end of the transistor and the second input end of the operational amplifier, and the other end coupled to a ground; and a reference voltage calibrator, coupled to the peak current detector, the reference voltage generator and the comparator, for outputting the adaptive reference voltage to the comparator; a comparator, coupled to the reception end and the adaptive reference voltage generator, for comparing the current sense signal and the adaptive reference voltage, to generate a comparison result; and a control unit, coupled to the comparator, for controlling a switch transistor of the power supply according to the comparison result.