A broadband microwave GaN HEMTs class EF₃ power amplifier with π-type network

Abstract

A GaN HEMTs class EF₃ power amplifier (PA) with π-type network for broadband operation is presented in this paper. The π-type network is constructed by shunt capacitance, series inductance and finite dc-feed inductance, where the series inductance includes the parasitic inductance effects of transistor. As a result, the topology can make full use of the parasitic effects of transistor to raise the operation frequency. Moreover, it is found that this topology can also increase the frequency bandwidth. For demonstration purpose, a PA prototype based on the topology is fabricated. Experimental results show that the amplifier can operate from 2.9 GHz to 4.0 GHz (fractional bandwidth 31.8%) with a measured drain efficiency higher than 67%, and the output power is greater than 37.4 dBm. The proposed structure can be a good candidate for design of high efficiency and broadband class E power amplifiers.