Computer aided characterization of bipolar transistor for CAD applications

A computer-aided procedure using s-parameter measurements and optimization is employed to determine the value of the parameters of the small signal transistor model. It is noted that the method considers the determination of the small-signal model parameters required as input for the SPICE program (which simulates a semiconductor circuit); this model which is built in, does not take into account package parasitics. Therefore, the frequency of operation has to be such that these parasitics do not have an appreciable influence. Finally, the results of characterizations of integrated and discrete transistors are presented and problems concerning errors and limitations of the procedure are discussed.