Patent ID: 7208927

Claim:
A method for soft-starting a switching regulator that includes an error amplifier, a compensation capacitor, a flip-flop, a comparator, and a bias current regulating circuit; comprising: monitoring a feedback voltage from the output terminal of said switching regulator; providing a shutdown signal when said switching regulator is either disabled, under or over-temperature, under-voltage, or over-voltage to reset said flip-flop that has set, reset, and output terminals; discharging said compensation capacitor responsive to said shutdown signal; comparing said feedback voltage with a first reference voltage through said comparator and if said feedback voltage becomes larger than said first reference voltage, the output signal of said comparator sets said flip-flop; and regulating the bias current of said error amplifier through said bias current regulating circuit responsive to said feedback voltage and the output signal of said flip-flop by: (1) if said feedback voltage is less than said first reference voltage, the bias current of said error amplifier is regulated to a small value to ensure a soft start for said switching regulator; (2) if said feedback voltage is larger than said first reference voltage, the bias current of said error amplifier has its normal value under normal operation; wherein said error amplifier operates under close-loop condition when its bias current switches from said small value to its normal value.