LED driver circuit and method of driving LED

摘要

A light emitting diode (LED) driver circuit is provided. The LED driver circuit includes an LED the LED; a power unit which provides a current to the LED through an inductor; a dimming switch which is connected to the LED and bypasses the current provided to the LED; an input unit which receives brightness information of the LED; a logic unit which calculates reference currents for each driving mode according to the received brightness information; a current control unit which controls the power unit to provide the current based on the driving mode and the calculated reference currents to the inductor; and a switch control unit which switches the dimming switch on if the driving mode of the LED driver circuit is switched to the dimming mode.

主权项

1. A light emitting diode (LED) driver circuit having a driving mode including a normal mode maintaining a brightness of an LED and a dimming mode changing the brightness of the LED, the LED driver circuit comprising:
the LED; a power unit which provides a current to the LED through an inductor; a dimming switch which is connected to the LED and bypasses the current provided to the LED; an input unit which receives brightness information of the LED; a logic unit which calculates reference currents for each driving mode according to the received brightness information; a current control unit which controls the power unit to provide the current based on the driving mode and the calculated reference currents to the inductor; and a switch control unit which switches the dimming switch on if the driving mode of the LED driver circuit is switched to the dimming mode, wherein the logic unit further calculates a reference current of the normal mode according to the received brightness information and calculates a reference current of the dimming mode less than the calculated reference current of the normal mode.