A systematic approach to the analysis of general and feedbackcircuits and systems using signal flow graphs and driving-pointimpedance

摘要

Feedback has long been a mysterious effect that has either fixednor ruined circuits. Phase- and loop-gain analysis have served tonmaintain this view of feedback by being difficult to handle and toninterpret. In this paper, a unified approach to circuit analysis isnpresented which readily handles feedback circuits using driving-pointnimpedance (DPI) techniques to directly generate a signal flow graphn(SFG). When coupled with pole-zero diagrams, a complete analytical toolnresults, giving the design engineer qualitative as well as quantitativenanswers. A simple extrapolation of the methodology shows it to benapplicable to systems composed of linear cells such as active filters,nwhere loading effects at input and output ports are automaticallynincluded in the analysis