[PWM ILLUMINATION CONTROL CIRCUIT WITH LOW VISUAL NOISE FOR DRIVING LED]

摘要

A pulse width modulation (PWM) illumination control circuit with low visual noise for driving a light-emitting diode (LED) is provided. An illumination control pulse-generating unit is used to generate an illumination control pulse signal according to an illumination-adjusting signal. The duty cycle or frequency of the illumination control pulse signal varies within a predetermined scope for controlling a DC/DC converter to drive the light-emitting diode so that overall visual noise level of the PWM illumination control circuit is improved.