Patent ID: 7855520

Claim:
A light-emitting diode (LED) driving circuit, comprising: a conversion circuit, which converts an input voltage into an output voltage according to a control signal; an LED module being coupled with the conversion circuit and emitting light according to the output voltage; a current detector being coupled with the LED module and generating a current detection signal according to a current flowed through the LED module; and a control module, including a secondary side control unit being coupled with the current detector and coupled with an isolation unit for receiving the signal output by the secondary side control unit and accordingly generating a secondary side signal, generating the control signal according to the current detection signal and a dimming signal, so as to control the output voltage at a first driving voltage or a second driving voltage; wherein when the output voltage is controlled at the first driving voltage, the LED module is in a stably lighting state; and when the output voltage is controlled at the second driving voltage, the LED module is close to a non-lighting state; wherein the second driving voltage is approximate to a threshold voltage of the LED module.