In this paper, a scalable large signal GaN HEMT model including nonlinear thermal sub-circuit is described. Only two scalable parameters are needed in the Ids scalable model by introducing a simple correction factor. The established model can predict the I–V curves at different-in-size AlGaN/GaN HEMTs devices accurately. Small signal S-parameters and large signal load pull tests with on-wafer measurement is used to further validate the proposed model. Finally, the proposed scalable model is used to design a broadband high efficiency continuous class-E power amplifier (PA). Experimental results show that this class E PA is realized from 2.5-3.5GHz with drain efficiency of 60%-70%, over 8.2dB gain and over 35.2dBm output by using a GaN HEMT with 1.25mm total gate width. The results show that the proposed model is useful for high efficiency amplifier design.
2017 by The Institute of Electronics, Information and Communication Engineers