Patent ID: 8098027

Claim:
A light-emitting device driving circuit, adapted to driving a light-emitting device, wherein a terminal of the light-emitting device is coupled to a supply voltage and a cathode of a diode via an inductor and the other terminal of the light-emitting device is coupled to an anode of the diode, the light-emitting device driving circuit comprising: a switch, having a first terminal, a second terminal and a control terminal, the first terminal of the switch being coupled to the other terminal of the light-emitting device; a current-sensing circuit, coupled to the second terminal of the switch and determining whether or not to generate a turning-off control signal according to a conducting-current value of the switch; and a switch control circuit, coupled to the current-sensing circuit and the control terminal and the second terminal of the switch to control an on/off state of the switch, wherein when the switch control circuit turns on the switch, the switch control circuit compares the conducting-current value of the switch and a reference-current value to generate a comparing result, turns off the switch according to the turning-off control signal, and dynamically adjusts a turning-off time length of the switch according to the comparing result.