摘要
LED光源作为新型绿色环保光源,具有寿命长,发光效率高,高亮度以及工作电压低等优点。基于LED驱动电路的过温保护以及降低功耗要求,本文设计了一种用正温敏电阻来自动调节LED驱动电流以及降低采样电阻功耗的LED驱动电路,与常用的LED驱动电路相比,其优点在于:在温度达到保护点时,驱动电流不是直接降为零,而是在不被人眼明显发觉光变的前提下,LED驱动电流随系统温度的增加而适当的降低,因此,更适应照明等领域。本文所选取的LED驱动电流为ILED=350mA,LED灯阵列由M×N矩阵形式组成。
LED light source as a new,green and environmental friendly light,has advantages of long life,high luminous efficiency,high brightness and low operating voltage.In view of the requirements of over-temperature protection and reduce power consumption about LED drive circuits,this paper introduces a LED driver circuit for temperature-sensitive resistor to automatically adjust the LED drive current and reduce the sampling resistor power.Compared with the commonly used LED,this circuit has an advantage over the others.When the temperature comes to protection point,the LED drive current is not directly reduced to zero,but be decreased softly with the increases of the system temperature,in the premise of changes in flux are not obviously detected by human eyes.Therefore,it is more suitable for lighting and other fields.This paper select 350 mA LED drive current and the LED light array is composed of M×N matrix.
出处
《电路与系统学报》
北大核心
2013年第1期353-356,347,共5页
Journal of Circuits and Systems
关键词
LED驱动电路
低功耗
正温敏电阻
LED drive circuit
low power consumption
positive temperature-sensitive resistor
