由于实际运算放大器与理想运算放大器的主要参数存在较大的差别,导致实际运算放大电路存在较大的动态误差。该文采用节点电位分析法,从运算放大电路的频率特性出发,以反相积分运算放大电路为例,详细讨论了正弦输入信号和阶跃输入信号作用下,由于开环直流电压增益、增益带宽积有限而引起积分运算的动态误差。可以得出明确的结论和相应电路元件及参数的选取原则,为高精度运算放大电路动态误差的分析提供了参考,有利于高精度运算放大电路的设计。
Because the main parameters of the actual operational amplifier and the ideal operational amplifier are different, this leads to the actual operational amplifier circuit has the dynamic error. When input signals are sinusoidal signal and step signal, by u- sing node voltage analysis method and frequency response method, this paper discusses in detail the dynamic error of operational ampli- fier circuit due to the fact that open loop DC gain and gain bandwidth product are not infinite. Then one can draw a clear conclusion and the principles for selection of circuit components and parameters, which provide a reference for dynamic error analysis of high precision operational amplifier circuit. It is beneficial to design high precision operational amplifier circuit.