一、前言在仪表装置中,为了减小环境温度对测量精度的影响,普遍使用着差动放大器。这类放大器之所以如此广泛的流传和沿用,是因为它与别种电路相比有其独特之优点,例如,它对供电电压之变化不敏感,因此可以降低对电源电压稳定性和对电源纹波的要求;它有较高的共态电压免除能力,因此可以放大诸如电桥两端微小的差值电压信号;它的电路简单, First, the preface In the instrumentation, in order to reduce the impact of ambient temperature on the measurement accuracy, widely used differential amplifier. The reason why such amplifiers are so widely spread and used because it has its own unique advantages compared with other circuits, for example, it is not sensitive to changes in the supply voltage, which can reduce the stability of the power supply voltage and the power supply pattern Wave requirements; it has a higher common-mode voltage immunity, it can amplify such as the bridge across the tiny differential voltage signal; its circuit is simple,