Patent ID: 9326341
Filing Date: 2016-04-26
CPC Classification: H05B

Claim Text:
1. A light-emitting diode (LED) driving circuit configured for driving at least one group of LEDs, wherein the LED driving circuit comprises: a constant current source configured for generating a current signal with a constant current value; a pulse width modulation (PWM) element electrically connected to the constant current source and configured for modulating the current signal to generate a PWM signal corresponding to the current signal, wherein the PWM signal comprises a plurality of pulses identical in width; and at least one pulse frequency modulation (PFM) element electrically connected between the PWM element and the at least one group of LEDs and configured for modulating a frequency width of the PWM signal to generate at least one PFM signal for driving the at least one group of LEDs; wherein when the at least one PFM element modulates the frequency width of the PWM signal, the at least one PFM signal is changed, and light-emitting frequencies of the at least one group of LEDs are also changed.