基于STM32的自动量程电压表的设计

本设计能够精确的测量直流电压、交流电压,具有测量精度高,抗干扰能力强等特点。整个系统可以用一块9V电池供电,实现了低功耗和便携功能。交流测量是用AD637真有效值转换芯片将交流信号转换成直流电压后测量;用带钳位保护的反向放大器进行输入电压转换,实现了10MΩ的输入阻抗和高安全性。电路中关键器件采用TI公司的精密运算放大器OPA07和仪表放大器INA128,实现了高精度的测量;ADC采用STM32f103ZET6片内自带的12位AD,实现了低功耗,量程自动切换功能。

The design can measure DC voltage, AC voltage is accurate, has the advantages of high measuring precision, strong anti-jamming capability etc.The whole system can use a battery of 9V power, low power consumption and portable function.AC measurement is AD637 true RMS converter chip measurement of AC signal into a DC voltage; reverse amplifier with a clamp on the protection of the input voltage, the input impedance of 10M and high security.The key device in the circuit using the TI company＇s Precision Operatlonal Amplifier OPA07 and instrumentation amplifier INA128, realized the high precision measurement; ADC uses 12 bit AD STM32F103ZET6 chip with built-in, low power consumption, automatic range switching function.