20110215731 | LED ILLUMINATION DRIVING APPARATUS - Provided is an LED illumination driving apparatus. When dimming is performed in the LED illumination apparatus, the power voltage level supplied to an LED module is selectively adjusted according to illuminance to prevent the flicker phenomenon occurring due to an excessive decrease in a duty ratio of a PWM control signal at a dimming time in the related art. More specifically, if the set illuminance is decreased by a user, the duty ratio of the PWM control signal is decreased, so that the illuminance of the LED illumination is decreased. When the duty ratio of the PWM control signal is decreased, if the user decreases the illuminance below a predetermined level corresponding to a threshold duty ratio where the flicker phenomenon occurs, the power voltage level transmitted to the LED module is decreased. The duty ratio is allowed to be increased again by the duty ratio corresponding to the decrease in the power voltage level, and after that, the duty ratio is allowed to be decreased again. Accordingly, it is possible to freely adjust the illuminance of the LED illumination apparatus while preventing the occurrence of the flicker phenomenon. | 09-08-2011 |