| 摘要 |
PURPOSE: A power converter is provided to be protected, by making an interleave PFC circuit and a resonant converter control circuit as a single chip and blocking the operational power source supplied to a power factor correction control part when an over voltage is outputted through the PFC circuit. CONSTITUTION: A power converter includes a bridge rectifier(20), an interleave switching converter(30), a DC-DC converter(50) and a resonance and a PFC control integrated IC(10). The bridge rectifier rectifies an AC input. The interleave switching converter comprises a first converter and a second converter connected in parallel with each other. The first converter includes a first switch, and the second converter includes a second switch. The interleave switching converter converts the output of the bridge rectifier into a DC power source through the first and second converter. The DC-DC converter includes a third and a fourth switch, and a transformer. The third and the fourth switch receives and switches a DC power source output of the interleave switching converter in turn and then outputs a signal with a resonant frequency. The transformer converts a signal outputted from the third and the fourth switch into a DC signal. The resonance and PFC control integrated IC includes an interleave PFC control block and a resonance control block. The interleave PFC control block controls the first and second switches of the interleave switching converter and compensates the power factor. The resonance control block controls to switch the third and fourth switches of the DC-DC converter in turn with the resonant frequency. The output part of the interleave switching converter includes an over voltage protection circuit(35b) which blocks the supply of an internal reference voltage of the resonance and PFC integrated IC when an output voltage is higher than a pre-established voltage. |
