| 摘要 |
<p>A microcomputer (18) of this power supply device comprises: a target duty-ratio calculating unit (31) that calculates a target duty-ratio (DUt), based on input voltage (Vin), input current (Iin), output voltage (Vo), and target voltage (Vt); and a duty-ratio calculating unit (33) that will calculate the duty-ratio (DU) of the current cycle so as to make the deviation between the target duty-ratio (DUt) and the duty-ratio (DUp) of the preceding cycle become gradually smaller, and which will lower the duty-ratio (DU) of the current cycle instantaneously, when the output voltage (Vo) exceeds a threshold voltage value (Vth1). Therefore, a soft start will be able to be conducted safely.</p> |
