Analysis and Design a 2.5 GHz Class-E Power Amplifier in Two Configurations

There are two circuit configurations that commonly used for Class-E power amplifiers, the Infinite DC-feed or Shunt capacitor configuration and the Finite DC-feed or Shuntinductor. Albeit these circuit configurations are not essentially different, however they show different behavior and performance. In this paper we have compared these Class-E configurations at 2.5 GHz. For this purpose, we have designed two class-E circuits, one with Infinite DC-feed configuration and the other with Shunt inductor configuration. We have used the GaN High Electron Mobility Transistor (HEMT) inboth designs. Optimized simulations showed 69% drain efficiency, 64% PAE, and 21.46 dBm load power, in the case of Infinite DC-feed design and 71% efficiency, 64.5% PAE, and 15.93 dBm load power in the case of Shunt inductor design. It is obvious that we should consider the importance of PAE inhigh power circuits and the importance of DE in low power circuits. The results propose that Infinite DC-feed design ismore suitable for high power applications, but the Shunt inductor design is better for low power applications.