Patent ID: 8098021
Filing Date: 2012-01-17
Classification: A61P,H05B

Abstract:
1. A driving circuit of a light emitting diode (LED), adapted to receive an AC power to drive the LED, the driving circuit comprising: a rectifier unit, rectifying the AC power to generate a first operating voltage; a voltage-dividing circuit, coupled to the rectifier unit for receiving the first operating voltage to generate a voltage-dividing signal corresponding to the first operating voltage; a control unit, comprising a regulating unit and a pulse width modulation (PWM) unit, wherein an output terminal of the regulating unit is coupled to the PWM unit, and the PWM unit outputs a PWM signal; a voltage converter, coupled between the control unit and the LED for driving the LED, and adjusting a driving voltage and a driving current of the LED according to the PWM signal; a resistor, coupled between an output terminal of the rectifier unit and a diode, and another terminal of the diode being coupled to a power input terminal of the regulating unit; and a first capacitor, coupled between the power input terminal of the regulating unit and a ground terminal, wherein the PWM unit adjusts the PWM signal according to the voltage-dividing signal and a feedback signal output by the voltage converter.