電容式位移傳感器轉(zhuǎn)換電路的設(shè)計(jì)

介紹一種用于動(dòng)平衡分析儀差動(dòng)電容式位移傳感器信號(hào)轉(zhuǎn)移電路。利用差動(dòng)測(cè)量技術(shù),
將由振動(dòng)引起的微小電容變化量轉(zhuǎn)化成交流電壓信號(hào)。電路由差動(dòng)放大電路、正弦信號(hào)發(fā)生器、模擬乘法器和二階低通濾波器組成,該電路線路簡(jiǎn)單、集成度高、便于調(diào)試。通過(guò)電壓轉(zhuǎn)換電路可以將- 10～ + 10 V 的輸出電壓轉(zhuǎn)變成為0～5V 的電壓,便于帶有A/ D 轉(zhuǎn)化電路的單片機(jī)系統(tǒng)直接進(jìn)行A/ D 轉(zhuǎn)換,簡(jiǎn)化了電路設(shè)計(jì)。實(shí)驗(yàn)表明該轉(zhuǎn)換電路具有較好的線性和抗干擾性。
關(guān)鍵詞:電容傳感器;動(dòng)平衡;電路;差動(dòng)測(cè)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