Patent ID: 8421365

Claim:
An apparatus for driving a light emitting device (LED), the apparatus comprising: a first driving control element configured to control a current flowing through a first LED channel, which is connected to an operating voltage terminal and includes a plurality of LEDs, in response to a first pulse-width modulated control signal; a first current detection unit connected between the first driving control element and a ground terminal, and configured to detect the current flowing through the first LED channel; a first effective value detection unit configured to detect an effective value of the current detected by the first current detection unit; a first reference signal generation unit configured to generate a preset reference signal having a sawtooth waveform; and a first comparison unit configured to compare the reference signal from the first reference signal generation unit with the effective value from the first effective value detection unit, wherein the first comparison unit is configured to be enabled when a dimming pulse-width-modulated (PWM) signal is at a high level, and disabled when the dimming PWM signal is at a low level.