| 摘要 |
A switching power supply circuit formed by providing a complex resonance type converter with a power factor improving circuit feeds back a voltage resonance pulse voltage generated in a primary-side voltage resonance converter to fast recovery type diodes via a tertiary winding or the tertiary winding and a series resonant capacitor by magnetic coupling to thereby improve a power factor to 0.9, and achieves an improvement in AC/DC conversion efficiency and a reduction in a ripple component of a direct-current output voltage by voltage doubler rectifier operation. Also, a first rectifier circuit and a second rectifier circuit shunt the current to be stored in a smoothing means, so that a range of zero volt switching operation is not narrowed even when the power factor is improved. <IMAGE> |
