Distortion analysis of nonlinear networks based on SPICE-oriented harmonic balance method

Distortion analysis in the frequency domain is very important for designing analog integrated circuits. We propose here a new method based on the SPICE-oriented harmonic balance method, where the Fourier transformations to the bipolar transistors and/or MOSFETs are carried out using a new Fourier transfer circuit model. The circuit is composed of the analog behavior models (ABM) of SPICE, which can be applied to any kind of nonlinear circuit elements described by exponential and/or piecewise linear functions. Furthermore, the determining equation of our harmonic balance method is schematically described by coupled resistive DC, Cosine and Sine circuits, so that we can easily obtain the frequency response curves with the DC analysis of SPICE. Thus, our approach is quite user-friendly, because we need not derive the circuit equation and the determining equations in our harmonic balance method.