摘要 |
A power supply device includes: a comparator that compares an error voltage and a slope voltage to generate a comparison signal; a PWM pulse generation portion that generates a PWM pulse based on a clock signal and the comparison signal; an on-time fixed pulse generation portion that uses the comparison signal as a trigger to generate an on-time fixed pulse where an on-time and an on-time number are constant; a one shot pulse generation portion that generates once, when a soft start voltage exceeds a predetermined threshold voltage, a one shot pulse where the on-time and the on-time number are constant; and a selector that selects any one of the PWM pulse, the on-time fixed pulse and the one shot pulse. |