Patent ID: 9510408
Filing Date: 2016-11-29
CPC Classification: H05B

Claim Text:
1. A light emitting diode (LED) driving apparatus, adapted to drive at least one LED string, the LED driving apparatus comprising: a sensing resistor, having a first terminal coupled to a cathode of the at least one LED string to generate a feedback voltage and a second terminal coupled to a ground potential; an adjustable voltage-divider circuit, configured to generate a reference voltage according to a dividing ratio, wherein the dividing ratio of the adjustable voltage-divider circuit is controlled by a first signal set and a second signal set; a comparator, having a first input terminal coupled to the first terminal of the sensing resistor to receive the feedback voltage, a second input terminal coupled to the adjustable voltage-divider circuit to receive the reference voltage and an output terminal configured to generate a control signal; a power converter, coupled between the output terminal of the comparator and an anode of the at least one LED string and configured to provide a DC voltage to the anode of the at least one LED string according to the control signal; and a control circuit, coupled to the adjustable voltage-divider circuit and configured to receive a dimming signal, wherein the control circuit counts a disable period of the dimming signal to generate the first signal set and counts an enable period of the dimming signal to generate the second signal set.