| 摘要 |
<p>The present invention relates to an LED driver for preventing errors of detecting a short circuit of an LED channel, and more specifically, to a technique for preventing the errors of detecting the short circuit of the LED channel by controlling a feedback responding speed when the drastic variation of an analog dimming signal for an LED dimming operation exists. The present invention provides the LED driver comprising: an analog dimming signal delay part for controlling the responding speed of the analog dimming signal (ADIM) before outputting; a voltage comparing part which primarily receives the output of the analog dimming signal delay part and secondarily receives feedback voltage (VFB) for comparing the voltage levels thereof and outputting the voltage levels; a short circuit determining part for determining the short circuit to be generated in the LED channel when the output of the voltage comparing part is measured to be a value equal to or less than a particular short detect level; an LED channel voltage generation part for increasing LED channel voltage (VLED) supplied to the LED channel before supplying when the output of the voltage comparing part is (+) and decreasing the LED channel voltage before supplying when the output of the voltage comparing part is (-); a PWM dimming control part for turning on and off current flowing in the LED channel; and a feedback voltage detection part for secondarily inputting the feedback voltage (VFB) corresponding to the current flowing in the LED channel to the voltage comparing part.</p> |
