Patent ID: 8049436

Claim:
A dimmer apparatus, adapted to receive an AC power to drive a light-emitting diode (LED), comprising: a rectifier unit, rectifying the AC power to generate a first operating voltage; a voltage divider, coupled to the first operating voltage for generating a voltage division corresponding to the first operating voltage; a controller, coupled to the voltage divider for integrating the voltage division to obtain an average voltage, and outputting a pulse width modulation (PWM) signal according to the average voltage; and a voltage converter, coupled between the controller and the LED for driving the LED, and adjusting a driving voltage and a driving current of the LED according to the PWM signal, wherein the controller further adjusts the PWM signal according to a feedback signal generated by the voltage converter, wherein the rectifier unit comprises: a rectifier, rectifying the AC power to generate the first operating voltage; a filter, coupled to an output of the rectifier, for outputting a filtered voltage; and a regulator, coupled to an output of the filter, for outputting a second operating voltage to the controller.