| 摘要 |
PURPOSE: To obtain a small and lightweight power supply having high power factor and high efficiency by setting the input power factor at 1 and controlling a resonance converter simultaneously while minimizing the high frequency content of AC input current. CONSTITUTION: A high power factor power supply comprises a radio wave rectifying section 3, a radio wave rectification signal detecting section 4, a capacitor C1 , an inductor L1 , a high frequency switching section 6, a resonance circuit section 7, an output circuit section 8, and a control section 5. The control section 5 comprises a saw-tooth wave signal generator 54, a first comparator 51 for comparing a signal from the radio wave rectification signal detecting section 4 with a signal from the saw-tooth wave signal generator 54, and a frequency dividing circuit 55 for generating a switching control signal having a zero region between switching pulses depending on the outputs from the first and second comparators 51, 52. |
