Class-E high efficiency power amplifiers

Three switching mode power amplifiers are realized with collector (drain) efficiencies of 87%, 86% and 92% at 430 MHz/5 W, 100 MHz/12 W, and 5 MHz/62 W, respectively. These high efficiencies are achieved by the class-E technique and low insertion-loss load networks. Detailed design rules and major parameters are presented. Because the output power is limited by collector-emitter breakdown voltage and collector current, not the rated power output from the databook, a 5-W output using a 4-W rated power transistor without special heat-sink is achieved