低频低噪声测量放大器的设计  

Design of low frequency and low noise measuring amplifier

作　　者：陈晓娟[1] 樊欣欣[2] 吴洁[3] 

机构地区：[1]长春理工大学电子信息工程学院,吉林长春130022 [2]东北电力大学信息工程学院,吉林吉林132012 [3]北华大学电气信息工程学院,吉林吉林132013

出　　处：《现代电子技术》2016年第10期116-119,共4页Modern Electronics Technique

基　　金：国家自然科学基金资助项目(61271115);吉林省自然科学基金资助项目(20101519)

摘　　要：低频噪声是表征半导体器件质量和可靠性的一个重要敏感参数,为了能够测量电子器件低频噪声,使用分立器件SSM-2220组成偏置电路,由ADA4898-1构成前置放大器,采用噪声匹配变压器法设计一种测量低频低噪声的放大器。实验结果表明:在频率为80 k Hz以下,放大器输入端共模抑制比高出集成运放OP-37 228 d B,其系统的噪声系数低于前置放大器ADA-40752 0.3 d B,满足低频低噪测量放大器的设计要求。The low-frequency noise is an important sensitive parameter to character the quality and reliability of semiconductor devices. To detect the low-frequency noise of electronic devices,an amplifier measuring the low-frequency and low noise was designed by means of the method of noise matching transformer,in which there are a biasing circuit composed of the discrete device SSM-2220 and a preamplifier constituted with ADA4898-1. The experimental results show that the common-mode rejection at input end of the amplifier is 228 d B higher than that of OP-37 as the frequency is below 80 k Hz,and the system noise coefficient is 0.3 d B lower than that of preamplifier ADA-40752. This amplifier can meet the design requirements of low frequency and low noise detecting amplifier.

关 键 词：分立元件 前置放大器 噪声匹配变压器 低频噪声测量 

分 类 号：TN722.334[电子电信—电路与系统]