摘要
在对普通恒流源加以变形的基础上,设计了一种可以驱动多路发光二级管的镜象电流源。利用D/A转换器和精密运放实现V/I转换及恒流连续可调。采用晶体管扩流,ULN2003进行多路电流切换。测试表明,V/I转换电路的输入电压和镜象输出电流之间具有良好的线性关系,恒流精度达0.05%。
Based on the transformation of common constant current source was designed for driving multi-channel constant current were realized with D/A converter and current source, a novel circuit of mirror constant LED. The V/I conversion and continuous tune of high precision operational amplifier. The transister was used for current amplification and ULN2003 was used for multi-channel current switch. The results showed that there was a good linear relationship between the input voltage of VII converter and the output current of mirror circuit. The precision of constant current was 0.05 %.
出处
《分析仪器》
CAS
2009年第1期7-10,共4页
Analytical Instrumentation
基金
自然科学基金资助项目(20575024)
