| 摘要 |
A power factor correction circuit includes a rectifier 3 to rectify an AC voltage of an AC power source 1, a first series circuit connected in parallel with an output of the rectifier and having a step-up reactor L1 and a switching element Q0 that are connected in series, a second series circuit connected in parallel with the switching element and having a rectifying diode D1 and a smoothing capacitor C2 that are connected in series, an oscillation circuit 12 to generate a clock signal CLK having a predetermined oscillation frequency, and a control circuit 10 to generate, at the period of the clock signal generated by the oscillation circuit and according to a voltage value of the smoothing capacitor, a drive signal for driving the switching element. The oscillation circuit changes the predetermined frequency according to the drive signal for the switching element. |
