用于压电料位计的微弱信号检测电路设计

设计了一种用于压电料位计的微弱信号检测电路，从防积分饱和电荷放大、带通滤波、精密检波、两级比较和逻辑控制五个方面介绍了其工程实现。能够实现单极性电源供电处理交流信号，实时监测料位计输出电荷大小，并转换为开关信号输出；具备灵敏度调节功能，可以根据不同物料的阻尼特性，有针对性地设置动作阈值；能够根据用户需要设置输出电平极性，提高了料位计的灵活性和适应性。结合理论计算、仿真分析和试验测试，验证了设计的合理性和正确性。

Design of Micro Signal Detection Circuit for Piezoelectric Level Gauge

A micro signal detection circuit for piezoelectric level gauge is designed.Its engineering implementation is introduced from five aspects:anti-saturation charge amplification，band-pass filtering，precision detection，two-stage comparison and logic control.It can process AC signal with unipolar power，monitor the output charge of material level gauge in real time，and convert it into switch signal output.With the function of sensitivity adjustment，the action threshold can be set according to the damping characteristics of different materials.And the polarity of the output level can be set according to the user’s needs，by which the flexibility and adaptability of the level gauge is improved.Combined with theoretical calculation，simulation analysis and experimental test，the rationality and correctness of the design are verified.