| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a power-factor correction circuit that allows reducing cost of a power-supply circuit corresponding to a plurality of input levels (or output levels).SOLUTION: A power-factor correction circuit 4 is connected to a subsequent stage of a rectifier circuit 3 rectifying an AC voltage Vin from an AC power supply 1. When assumed that a charge and discharge current Ic flowing through a capacitor 7 provided at an input side of the power-factor correction circuit 4 is not present, the power-factor correction circuit 4 controls a circuit current (PFC current Ipfc) so that the amount of current in the last half of a half period is larger than the amount of current in the first half of the half period in the half period of the AC voltage Vin.</p> |
