Development of 5 kW, 1 MHz Solid State RF Pulsed Power Amplifier Using Parallel Configuration of Four LDMOS Transistor at Device and Operated in Single Ended Mode

Abstract

A 5 kW and 1 MHz pulsed solid-state RF amplifier has been designed and developed to drive TH581 tetrode tube-based RF amplifier to realize 100 kW pulsed RF source. The driver amplifier is operated with a 1 ms pulse width at a 50 Hz repetition rate. The 5 kW RF power is obtained by operating four Gemini pair LDMOS transistors (VDD=50V) in parallel configuration at the device itself and having single-ended topology with common lumped element based input and output matching network. The amplifier delivers 5 kW RF power when fed by 25 dBm RF input drive from the signal generator. This scheme eliminates the need for RF combiner and divider which results in low loss, high efficiency, lesser number of components, simple and compact design. The measured saturated drain efficiency of the power amplifier is around 62%.