一种可调节低噪声恒流源电路  

Design of an adjustable and low-noise constant-current source circuit

作　　者：黄惠琳 陆小飞[2] 杨羽佳 黄静[1] 施佺[1] HUANG Huilin;LU Xiaofei;YANG Yujia;HUANG Jing;SHI Quan(School of Information Science and Technology,Nantong University,Nantong 226019,China;Xinglin College,Nantong University,Nantong 226019,China)

机构地区：[1]南通大学信息科学技术学院,江苏南通226019 [2]南通大学杏林学院,江苏南通226019

出　　处：《现代电子技术》2022年第2期16-20,共5页Modern Electronics Technique

基　　金：江苏省“333工程”科研项目(BRA2017475);南通市科技平台项目(CP12017001)。

摘　　要：为了满足半导体激光器(LD)对电流源高稳定性、低噪声的性能要求,文中基于负反馈原理设计一种可调节低噪声恒流源电路。该电路使用带隙基准电压源AD780BN提供低噪声、低温漂的基准电压,配合多路复用器ADG1606的选择功能,由低噪声运放LT1677构成的负反馈恒流驱动电路通过JFET将电压转换成电流,经过JFET和BJT构成的调整网络输出稳定的电流,实现了稳定的多电流输出。实际电路测试结果表明:该恒流源电路在3.8~5.5 V的输入电压范围内,输出电流稳定度在0.007%~0.029%之间;在电流调控模块控制下,输出电流从20~350 mA按30 mA的步进可调;最大输出电流噪声为2.8μA,具有低噪声的性能。In order to meet the performance requirements of semiconductor laser(LD)for high stability and low noise of current source,a constant-current source circuit with adjustable output is designed based on the principle of negative feedback.In the circuit,the bandgap reference voltage source AD780BN is used to provide the reference voltage with low noise and lowtemperature drift;with the selection function of the multiplexer ADG1606,the voltage is converted into current through JFET in the negative feedback constant-current driving circuit composed of low noise operational amplifier LT1677,and the stable current is output by the adjustment network composed of JFET and BJT,so that the stable multi-current output is realized.The actual circuit test results show that the constant-current source circuit has an output current stability of 0.007%~0.029% while the input voltage range is 3.8~5.5 V;under the control of the current regulation module,the output current is adjustable in 30 mA steps from 20~350 mA;the noise of the maximum output current is 2.8μA,which has the low noise performance.The method of eliminating surge impact caused by power switch is given.

关 键 词：电路设计 恒流源 低噪声电路 负反馈恒流驱动 涌浪冲击消除 电路测试 

分 类 号：TN86-34[电子电信—信息与通信工程]