电容式位移传感器转换电路的设计

介绍一种用于动平衡分析仪差动电容式位移传感器信号转移电路。利用差动测量技术,
将由振动引起的微小电容变化量转化成交流电压信号。电路由差动放大电路、正弦信号发生器、模拟乘法器和二阶低通滤波器组成,该电路线路简单、集成度高、便于调试。通过电压转换电路可以将- 10～ + 10 V 的输出电压转变成为0～5V 的电压,便于带有A/ D 转化电路的单片机系统直接进行A/ D 转换,简化了电路设计。实验表明该转换电路具有较好的线性和抗干扰性。
关键词:电容传感器;动平衡;电路;差动测量
　　Abstract :A transform circuit of capacitance sensor for dynamic balance instrument was given. By using a method of differnetial measurement ,it is can be used to detect a low capacitance changes caused by vibration. The circuit is consisted of differential amplifier circuit ,Signal generator ,Analog multipler and low - pass Filter. The circuit is simple and the inte2 gration is good. The voltage converted into 0～5 V using convering circuit can be used directly by microprocessor ,and con2 verted into digital signals by A/ D converting. So this simplifies the design of the circuits. The test showed that this circuit had a good linear charactre and anti - jamming.
Key Words :Capacitance Sensor ;Dynamic Blance ;Circuit ;Differential Measurement