A high efficiency, high voltage, balanced cascode FET

A high efficiency, high operating voltage GaAs HFET is presented. A balanced cascode circuit without RF feedback, which achieves the high PAE of 78.2% at 2.1GHz, is proposed. The optimization of a balance capacitor is analyzed theoretically and proved experimentally. This result contributes to the design of high voltage power amplifiers with low breakdown voltage transistors.