摘要
在分析了现代微弱信号检测的研究技术的基础上,设计了一种基于AD630芯片的锁相放大器电路,利用锁相放大器芯片内部的锁相与乘法功能,对参考信号与探测信号进行处理,实现了信号的锁相放大,通过合适的积分电路,实现了锁相放大器的设计。文章还对微弱信号的前置放大电路进行设计,从而提高了整个锁相放大器电路的整体性能。该电路成功应用于光纤痕量气体检测中,并实现了0.0001%浓度量级的一氧化碳痕量检测,提高了检测灵敏度,效果明显。
We designed an AD630 based lock-in amplifier circuit. We employed the phase-locked and multiplication functionalities of AD630 to process the reference and detection signal and realized the phase lock of a signal. We further obtained a lock-in amplifier by AD630 and an appropriate integration circuit. We also devised a preamplifier circuit for a weak signal, by which the global performance of the amplifier circuit is improved. We successfully applied the circuit to the optical detection of trace gases. It can detect carbon monoxide of 0. 0001% concentration. Results show that the circuit significantly improves the sensitivity of trace gases detection.
出处
《山东科学》
CAS
2009年第5期48-52,56,共6页
Shandong Science
基金
国家科技支撑计划项目(2006BAK03B00)
山东省科技攻关项目(2009GG10007016)
山东省重大专项项目(2008ZHZX1A0308)
作者简介
倪家升（1982-），男，硕士，主要从事于光纤传感器技术研究。通讯作者：E-mail：njsh51@163．com
