LED drive circuit

摘要

An LED drive circuit of the disclosed subject matter can include an LED unit and a serial circuit connected in parallel therewith. The serial circuit includes a resistor and a positive temperature coefficient resistor having a positive linear temperature coefficient. A voltage across the positive temperature coefficient resistor is fed back to an output control circuit. An output voltage that is PWM-controlled on the basis of a reference voltage set at the output control circuit is used to drive the LED unit.