MULTI-MODE CONTROL METHOD FOR ACTIVE CLAMP FLYBACK CONVERTER

摘要

Provided in the present invention is a multi-mode control method for an active clamp flyback converter. In the flyback converter, a controller implements mode switching between a trailing edge non-complementary mode, a leading edge non-complementary mode, and a leading edge non-complementary Burst mode of two drive signals after comparing a detection feedback voltage to a set mode switching threshold voltage. The present invention uses the trailing edge non-complementary mode to reduce the circulating current of the converter, and uses the leading edge non-complementary mode to replace a common flyback mode, thus enhancing the light-load efficiency. The leading edge non-complementary Burst mode is used when there is no load, thereby limiting the magnitude of primary edge peak current during the Burst mode, preventing the generation of audio noises, and no-load power consumption is low.