【摘要】 隔离运算放大器是一种测量放大电路，采用振荡器、脉冲变压器、运算放大器、调制解调电路及有源低通滤波器设计了一款磁隔离运算放大器。输入端选用高性能运算放大器SGM8249,通过配置外部电阻使输入电压为-500～500 mV时，输出可调电压为-10～10 V。此外，还设计了输出电压为±15 V、输出电流为±15 mA的隔离直流电源。该放大器共模电压均方根值为3 500 V,共模抑制比大于120 dB,非线性度不大于0.05%。该隔离运算放大器具有体积小、精度高、实用性强的优点。更多还原

【Abstract】 Isolated operational amplifier is a measurement amplifier circuit. A magnetically isolated operational amplifier was built by using an oscillator, a pulse transformer, an operational amplifier, a modulation and demodulation circuit and an active low-pass filter. The high performance operational amplifier SGM8249 was used at the input end. And the output voltage can be adjusted from-10-10 V when the input voltage is-500-500 mV through the configuration of the external resistor. Besides, an isolated DC power supply with an output voltage of ±15 V and an output current of ±15 mA was designed. The common-mode voltage root mean square value of the amplifier is 3 500 V, common-mode rejection ratio is more than 120 dB, and the non-linearity is no more than 0.05%. The isolated operational amplifier has the advantages of small size, high precision and practicality.更多还原