集成运算放大电路噪声谱矩阵计算及噪声性能分析

The Noise Matrix Calculation and Performance Analysis of the Operation Amplifier

由于集成运放电路内部具有大量噪声源，特别是运算放大器本身等效输入电压和电流噪声源的相关性，使运放电路噪声分析较困难。常用的噪声功率迭加方法由于无法考虑噪声源相关性会引起较大误差。本文提出用噪声谱矩阵表示具有噪声相关的运算放大器ｅ-ｉ噪声，推导了集成运放电路等效输入噪声谱迭加公式。不仅可以对运放电路的噪声进行准确计算及性能分析，而且可以计算电路内各噪声源的贡献，对低噪声集成运放电路参数设计有重要指导意义。

The noise analysis of an Op amplifier is not simple due to a lot of noise sources inside Op amplifier. Since the noise voltage sources of Op amplifier are correlated with the noise current sources, the conventional method based on the noise power superposition of individual noise source inside circuit will introduce significant error. In this paper, the equivalent input noise matrix of an Op amplifier has been presented based on the noise matrix method, The benefits of this expression are that the correlation between the noise voltage and current of Op amplifier can be considered completely and the analysis of the noise contribution of individual noise source inside circuit to equivalent input noise model can be obtained.