Patent ID: 8581502

Claim:
A light-emitting diode (LED) control circuit for controlling and driving at least an LED, through which a current is controlled by a current-controlled device comprising a control node, the LED control circuit comprising: a driving circuit comprising: a first comparator for comparing a sensing signal and a current-setting signal to generate a first comparison signal, wherein voltage of the sensing signal represents the current flowing through the LED; and a relay circuit for generating a driving signal according to the first comparison signal, and outputting the driving signal to the control node for driving the current-controlled device; and a fault detector comprising: a second comparator for comparing the first comparison signal and the driving signal to generate a second comparison signal; a third comparator for comparing the driving signal and a threshold voltage to generate a third comparison signal; a fourth comparator for comparing the sensing signal and the current-setting signal to generate a fourth comparison signal; and a decision maker for enabling or disabling the driving circuit according to the second, third, and fourth comparison signals.