Patent ID: 8884547

Claim:
A current regulating circuit of light emitting diode having a low voltage terminal and a high voltage terminal, the current regulating circuit comprising: a capacitor, including a first terminal and a second terminal, wherein the first terminal of the capacitor is electrically coupled to the low voltage terminal of the light emitting diode, and the second terminal of the capacitor is electrically coupled to a preset voltage; an inductor, including a first terminal and a second terminal, wherein the first terminal of the inductor is electrically coupled to the low voltage terminal of the light emitting diode; a diode, including a positive terminal and a negative terminal, wherein the positive terminal of the diode is electrically coupled to the second terminal of the inductor, and the negative terminal of the diode is electrically coupled to the high voltage terminal of the light emitting diode; a switch, including a first terminal and a second terminal, wherein the first terminal of the switch is electrically coupled to the second terminal of the inductor, and the second terminal of the switch is electrically coupled to the preset voltage; and a detection circuit, for detecting the voltage value of the low voltage terminal to thereby control the switch to be ON-state when the voltage value of the low voltage terminal is higher than a reference voltage and control the switch to be OFF-state when the voltage value of the low voltage terminal is lower than the reference voltage; wherein the voltage value of the low voltage terminal is greater than the preset voltage and smaller than the voltage value of the high voltage terminal.