Theory and application of the field-effect transistor. Part 2: High-frequency properties

The derivation of a small-signal high-frequency equivalent circuit is traced from the original Shockley form to a form that includes the effects of the junction capacitances and parasitic resistances. A system of measurements to determine the values of the equivalent circuit elements is described, and experimental results are presented for a number of commercially available field-effect transistors. The measurement scheme includes a number of checks on the above determinations, and these are presented as well. Finally, the adequacy of the derived equivalent circuit is demonstrated by comparing the computed and measured response of a field-effect transistor to a small-signal pulse with a rise time in the nanosecond range.