Spice-Oriented Frequency-Domain Analysis of Nonlinear Electronic Circuits

Abstract

†a) , Yousuke TANIGUCHI † †b) , Masayoshi ODA † †c) , Yoshihiro YAMAGAMI † †d) , Yoshifumi NISHIO † †e) , Members, and Akio USHIDA †f) , Fellow SUMMARY Distortion analysis of nonlinear circuits is very important for designing analog integrated circuits and communication systems. In this letter, we propose an efficient frequency-domain approach for calculating frequency response curves, which is based on HB (harmonic balance) method combining with ABMs (Analog Behavior Models) of Spice. Firstly, nonlinear devices such as bipolar transistors and MOSFETs are transformed into the HB device modules executing the Fourier transformations. Using these modules, the determining equation of the HB method is formed by the equivalent sine-cosine circuit in the schematic form or netlist. It consists of the coupled resistive circuits, so that it can be efficiently solved by the DC analysis of Spice. In our algorithm, we need not to derive any troublesome circuit equations, and any kinds of the transformations.

Envelope analysis of nonlinear electronic circuits based on harmonic balance method

“…The slowly varying system can be solved by an appropriate numerical integration formula. The third group of HB methods is a kind of symbolic method in the meaning that the HB determining equation called 'Sine-Cosine circuit' [27][28][29][30] is formulated by ABMs of Spice in the schematic forms [31,32]. These methods can easily get the frequency response curves of nonlinear circuits and the interesting nonlinear phenomena such as bifurcation phenomena [33,34] ‡ .…”