A Stacked FET Switch for use in a 20 kV Klystron Modulator

This paper describes a simple high voltage modulator incorporating a stacked power field effect transistor (FET) switch structure. The switch was prototyped and tested under various operating conditions to evaluate durability and performance. Several small, but significant changes to the standard series connected FET switch implementation were, added to improve the performance, lifetime and utility in service conditions. The basic modulator was developed to drive a klystron or TWT amplifier tube requiring a pulse of up to 20 kV and 10 A.