SMALL-SIGNAL TRANSISTOR CHARACTERIZATION FOR THE HF AND VHF RANGE.

A technique for the high-frequency characterization of small-signal transistors in the range of 3 to 300 Mc is proposed. The approach presented substitutes relatively accurate low frequency measurements for the normally hard to measure high frequency four-pole parameters. These low frequency measurements in conjunction with a derived set of y parameter expressions can be used to accurately characterize the frequency variation of a transistors four-pole parameters over the specified frequency range. An equally accurate characterization based on an equivalent circuit is relatively complex. The theoretical fourpole parameters obtained for both a germanium mesa and a silicon planar transistor are compared to the measured four-pole parameters obtained from an extremely accurate measuring set. The results show that an inaccuracy of five percent can be expected in most cases between the predicted and measured fourpole parameters. Author