LED driving circuit preventing light leakage issue

摘要

A light emitting diode (LED) driving circuit preventing light leakage issue. The LED driving circuit comprises an LED driver, a driving circuit module and a power supply. When an input voltage is much higher, a high frequency pulse width modulation signal is set to a low level to avoid a light leakage of the LED by turning off a metal oxide semiconductor field effect transistor (MOSFET), such that the input voltage is not limited by the light leakage of the LED. As a result, the input voltage can be increased sufficiently for further reducing a switching loss effectively.

主权项

1. A light emitting diode (LED) driving circuit applicable to an LED module, comprising:
an LED driver, comprising a first enable pin; a driving circuit module, comprising a metal oxide semiconductor field effect transistor (MOSFET), and a gate of the MOSFET being electrically coupled to a second enable pin; and a power supply; wherein the LED module, the LED driver and the driving circuit module are electrically coupled to each other, and the LED driver and the power supply are electrically coupled to each other, and the first enable pin is provided for receiving a high frequency pulse width modulation signal to drive the driving circuit module, and the driving circuit module further drives the LED module to emit light, and the second enable pin is provided for receiving the high frequency pulse width modulation signal, wherein the LED driver further includes a feedback signal pin, the driving circuit module further includes a resistor, and the feedback signal pin of the LED driver, an end of the LED module, the MOSFET, and the resistor are electrically coupled in series, and the MOSFET is electrically coupled in series between the feedback signal pin and the resistor, wherein when the MOSFET is turned off in response to the high frequency pulse width modulation signal, the LED driving circuit stops driving the LED module and then the LED module does not produce a light leakage.