提高LED稳定性的高精度数控恒流源

Design of a High Precision Digital Constant-current Source for improving the Stability of LED

近年来发光二极管越来越多的用作近红外光谱仪器的光源,发光二极管的稳定性直接影响光谱分析结果。本文介绍了一种用于提高LED光源稳定性的高精度数控恒流源电路,该电路基于单片机设计,由D/A转换电路和电流源电路组成,结构简单,输出从0￣165mA连续可调,恒流精度达到0.04%,光强稳定度优于±0.02%,结果满足光谱测量的要求。

At present,LED are widely used as light sources in spectrum instruments, the results of spectral analysis depend on the stability of LED.This article proposes the design of a high precision digital constant-current source for improving the stability of LED. The design is based on the single-chip processor, consists of the D/A transform circuit and the current source, and has the characteristics of simple structure,adjustable output from 0-165mA,a current precision of 0.04% and the stability of LED as high as ± 0.02%. The results meet the demand of spectrum measurement.