LED Circuit Having LED Driving Circuit and Operation Method of the Same

摘要

A LED circuit is provided. The LED circuit comprises LED channels and a LED driving circuit. The LED driving circuit comprises: a current mirror, a dc-to-dc converter and current sink modules each connected between one of the LED channels and an output load to lock the voltage at the output load at a level of a setting voltage. The current mirror comprises an input branch to generate an input setting current according to a variable setting load and an output branch to generate an output setting current to further generate a variable reference voltage and the setting voltage. A control module of the dc-to-dc converter generates a driving voltage according the variable reference voltage and a feedback voltage to control a gate of the power MOS of the dc-to-dc converter to further control the operation of the LED channels. A LED circuit operation method is disclosed herein as well.