Multi-path LED (light-emitting diode) driving circuit, backlight driving device and backlight illuminating system

Abstract

The invention is applicable to the field of illumination, and provides a multi-path LED (light-emitting diode) driving circuit, a backlight driving device and a backlight illuminating system. The circuit comprises a voltage stabilizing unit, a first light dimming control unit, a second light dimming control unit and a driving unit, wherein the voltage stabilizing unit is used for carrying out voltage division and voltage stabilization on the voltage of a power supply so as to reduce the fluctuation range of the power supply; an input end of the voltage stabilizing unit is connected with the power supply; the first light dimming control unit is used for generating a first light dimming signal after power is supplied; the second light dimming control unit is used for generating a second light dimming signal after the power is supplied; the driving unit is used for carrying out driving control and brightness regulation respectively on a first path of LED and a second path of LED according to the first light dimming signal and the second light dimming signal. According to the multi-path LED driving circuit, the backlight driving device and the backlight illuminating system, the fluctuation range of the voltage of the power supply is decreased by the voltage stabilizing unit, the driving unit is prevented from being burned out due to too high voltage, and moreover, a plurality of light dimming signals are generated respectively by the independent light dimming control units, so as to drive the brightness of multiple paths of LEDs, so that the driving control of the LED is more flexible.

Description

technical field [0001] The invention belongs to the lighting field, and in particular relates to a multi-channel LED driving circuit, a backlight driving device and a lighting system. Background technique [0002] Light Emitting Diode (LED) is known as the fourth-generation lighting technology. In recent years, it has been widely used mainly in backlight applications. For the driving of LEDs, most of them currently use dimming voltages from 5V to 28V to achieve drive control. However, when LED applications are limited by natural conditions or use conditions, for example, in coal mine environments, the power supply fluctuates greatly, often reaching 40V, which greatly exceeds the range of existing dimming voltages. Stability leads to burning of the drive circuit, and the miner's lamp cannot be illuminated. [0003] Moreover, most current multi-channel LED drivers use a separate drive source for each LED to drive, resulting in waste of resources and high costs. If multiple LE...

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Problems solved by technology

[0004] The purpose of the embodiments of the present invention is to provide a multi-channel LED drive circuit, which aims to solve the problem that the dimming control voltage range of the current LED drive circuit is narrow and the multiple channels cannot be individually dimmed.

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