大功率LED高频驱动电路设计

由于白光LED具有低成本、长寿命和小体积的特性,被迅速应用到了照明和背光等领域,其驱动电路也层出不穷,但大多数驱动源都没有解决效率不高,LED发光亮度不一致,发热量大等问题。该文提出了一种基于恒流二极管的大功率LED高频驱动方案,以带可控端的2THL系列恒流二极管为驱动元件,通过在控制端输入高频脉冲小信号控制恒流二极管通断,从而实现高频恒流驱动大功率LED这一目的。调节脉冲信号占空比即可实现LED调光。该文设计的驱动电路不仅能够保证LED持续、稳定、高效地工作,在一定程度上减小了LED芯片发热量,提高了LED灯具使用寿命,并且对输入电源要求不高,整体可以节能40%左右。

The Design of High-frequency Driver Circuit for High-power LED

As the white LED has the feature of a low-cost,long life and small size,it is quickly applied to the areas of lighting and backlighting.The LED driver circuits emerge in an endless stream,but most driving source do not resolve the problems of low efficiency,LED brightness inconsistent and LED large heat.This paper presents high-frequency driver circuit of high-power LED,based on current regulative diode.The drive component is 2THL series current regulative diode with control pin.It inputs high-frequency pulse small-signal to the control pin to control current regulative diode off and on,in order to drive high-power LED with high-frequency and constant current.LED dimming can be achieved by adjusting the duty cycle of pulse signal.The drive circuit of this paper not only ensures that the LED works constantly,steadily and efficiently,but also reduces the heat of LED chip,improves the service life of LED lamps,and demands little on the input power,the overall energy savings around 40%.