A Multi-Channel Dc/Dc LED Driver with Inductor-Less Series-Parallel Auto-regulated Rectifier

摘要

An inductor-less series-parallel auto-regulated rectifying circuit is proposed for multi-channel Dc/Dc LED driver.Utilizing the charge balancing principle in capacitors and the proposed series-parallel auto-regulated secondary rectifying circuit,accurate current sharing among output LED strings is achieved.By using resonant converter as primary side inverter circuit,a resonant Dc/Dc LED driver for four LED strings is constructed.The operating principle and AC circuit equivalent are presented.The current sharing capability for each output is also discussed.A four-channel output prototype with 0.35A/channel is built up to verify the theoretical analysis.