| 摘要 |
A switching power converter configured in a bridgeless totem pole boost topology has an inductor 112 which is switched to an output capacitor 116. The totem pole topology comprises a multilevel switching arrangement. The converter may be an AC�DC converter and may be provided as a PFC stage in a power supply. The multilevel switching arrangement may comprise a plurality of switches 130-140 arranged in series. The switching devices may be diodes or thyristors. The multilevel switching arrangement may also comprise flying capacitors 144, 146. Further embodiments include: a pulse transformer for providing on and off control pulses to each of a pair of complementary switches; a multilevel resonant transition type converter, suitable for use in providing enhanced hold�up from a bulk capacitor; a multi�ratio bus converter using a multilevel converter with a plurality of nominally discrete gain values; and an integrated circuit for use in a switching power supply, the integrated circuit comprising a plurality of at least four FET type transistors. |
