Patent ID: 8779682

Claim:
An illumination driving apparatus comprising: a rectifying unit rectifying a phase-controlled waveform of an alternating current (AC) power; a comparing unit comparing an output waveform of the rectifying unit with a first voltage according to a preset reference clock; a reference voltage generating unit sequentially storing outputs of the comparing unit, and generating a reference voltage corresponding to the number of high signals higher than the first voltage among the sequentially stored outputs of the comparing unit during one cycle of the output waveform; and a pulse width modulation (PWM) signal generating unit generating a PWM signal from the reference voltage and a feedback voltage, wherein the reference voltage generating unit includes: a shift register sequentially storing the outputs of the comparing unit output according to the reference clock; a register storing data corresponding to one cycle of the output waveform when the data is stored in the shift register; and a voltage generating unit generating the reference voltage based on a value of the data stored in the register.