Identification of small-signal transistor models

The identification of small-signal transistor models from experimental data is an area where much time may be wasted in attempts to fit inadequate data and models. In order to keep the efforts at an acceptable level, some kind of a systematic approach must be enforced. The author outlines and exemplifies a procedure which has proven successful with a broad range of bipolar and FET transistors. The three obvious requirements for getting accurate small-signal transistor models are: a reliable and sensitive optimization program for fitting models to measured small-signal parameters, accurate measurements, and a suitable equivalent circuit. The author demonstrates an approach to getting accurate small-signal transistor models based on an efficient optimization program, LCP2, accurate measurements, and a strategy for identifying equivalent circuits