摘要
压电传感器输出的压电信号较弱,输出阻抗高且叠加有共模干扰;现有的几种利用仪用放大器的压电信号前置放大电路解决方案有一些不足。在理论分析的基础上,对压电信号前置放大电路做了重要改进,提出了具有共模电压并联负反馈电路的压电信号放大电路前置级方案。实验显示,该方案能有效抑制共模干扰、提高电路的信噪比。
Signal from piezoelectric sensor is weak and often mixed with common-mode interference. The current schemes for piezoelectric signal pre-amplifiers based on instrument amplifier always appear some problems. On basis of theoretical analysis, an improved scheme for the piezoelectric signal pre-amplifier is proposed. A prestage scheme of piezoelectric signal amplifier about voltage-parallel connection negative feedback circuit with common-mode interference attenuation is proposed. The experiment indicates that the proposed scheme can improve the SNR and restrain common-mode interference.
出处
《现代电子技术》
2011年第10期179-181,共3页
Modern Electronics Technique
基金
无锡科技引导项目(2008409)
南京大学金川联合实验室资助项目(JLMC-YY2009101)
关键词
超声
压电信号
仪用放大器
共模干扰
ultrasonic sound
piezoelectric signal instrument amplifier
common-mode interference
