Due to feedback amplifier analysis simplification, Miller theorem, feedback theorem and Gray–Searle theorem are the most used tools on the calculation of the frequency response. However, they are only approximated results and then are invalid for overall closed-loop voltage gain of the frequency response. The traditional feedback theory, Miller theorem and Gray–Searle theorem are troublesome due to the significant difficulty of using the Kirchhoff's voltage/current law and Thevenin equivalent theorem. Especially, the utilisations of the Kirchhoff's voltage/current law and Thevenin equivalent theorem will be impractical for the complicated differential amplifier with the active load that contains four dependent sources and three bridge elements. The study proposes exact and algebraic frequency response analysis of a feedback amplifier by using the authors series research-Chen's Electric Unifying Approach with L'Hospital rule and Cramer's rule to take the place of those traditional approaches. Some experimental and mathematical results have exploited the fact that the proposed approach can yield the more effective and practical DC quiescent analysis with bias values and AC frequency response analysis with two junction charge-storage capacitances for the common-emitter amplifier with emitter resistance. Some experiments are provided to demonstrate the effectiveness of the proposed method.

中文翻译：

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查找反馈放大器精确频率响应的新方法

由于简化了反馈放大器分析，Miller定理，反馈定理和Gray-Searle定理是计算频率响应时最常用的工具。但是，它们只是近似结果，因此对于频率响应的整体闭环电压增益无效。由于使用基尔霍夫电压/电流定律和戴维南等效定理非常困难，传统的反馈理论，米勒定理和格雷-塞尔定理很麻烦。尤其是，对于具有四个负载源和三个桥元件的有源负载的复杂差分放大器，基尔霍夫电压/电流定律和戴维南等效定理的利用将是不切实际的。该研究通过使用作者的系列研究-具有L'Hospital规则和Cramer规则的Chen的电子统一方法来代替这些传统方法，从而提出了反馈放大器的精确和代数频率响应分析。一些实验和数学结果利用了以下事实：所提出的方法可以为带有发射极电阻的共发射极放大器提供更有效，更实用的直流静态分析（带有偏置值）和带有两个结电荷存储电容的交流频率响应分析。提供了一些实验来证明所提出方法的有效性。一些实验和数学结果利用了以下事实：所提出的方法可以为带有发射极电阻的共发射极放大器提供更有效，更实用的直流静态分析（带有偏置值）和带有两个结电荷存储电容的交流频率响应分析。提供了一些实验来证明所提出方法的有效性。一些实验和数学结果利用了以下事实：所提出的方法可以为带有发射极电阻的共发射极放大器提供更有效，更实用的直流静态分析（带有偏置值）和带有两个结电荷存储电容的交流频率响应分析。提供了一些实验来证明所提出方法的有效性。