Patent ID: 9030128
Filing Date: 2015-05-12
Classification: H05B

Abstract:
1. A light emitting diode (LED) drive circuit applied between an LED load and an AC power supply, wherein the LED drive circuit comprises: a rectifier used for rectifying and converting an alternate current (AC) voltage outputted from the AC power supply into a direct current (DC) voltage; a power conversion module electrically connected to the rectifier and the LED load for converting and outputting the DC voltage into a first drive voltage and a second drive voltage, wherein the first drive voltage is used to drive the LED load to provide necessary power for operation; a voltage regulator electrically connected to the power conversion module for receiving and processing the second drive voltage with a voltage regulating process to generate a third drive voltage; a photo coupler electrically connected to an input end of the LED load for generating a feedback signal according to an output signal outputted from the input end; and a controller electrically connected to the voltage regulator and the photo coupler for receiving the third drive voltage and generating a control signal according to the feedback signal, wherein the control signal controls the power conversion module by using a pulse width modulation (PWM) technology; wherein, the voltage regulator controls the third drive voltage not to exceed a maximum voltage rating of the controller.