GaN/AlGaN HEMT microwave class-E power amplifier

We report the first GaN/AlGaN microwave class-E power amplifier. A physics-based nonlinear model of the GaN/AlGaN HEMT is used instead of the switching models of the active device considered in previous works. The expressions of load network components of the class-E amplifier are derived considering exponential decay of the drain current during fall time and finite quality factor of the resonant circuit to incorporate the nonidealities of the active device and passive components. The class-E amplifier has been simulated using the Cadence circuit simulator using different HEMT structures. Calculated output power and power conversion efficiency are 93 mW and 72% at 1 GHz that decreases to 69 mW and 68% at 11 GHz, respectively for a 1 μm×150 μm GaN/Al_0.25Ga_0.75N HEMT. For a 0.12 μm×100 μm GaN/Al_0.20Ga_0.80N HEMT the corresponding quantities are 131 mW, 82%, 87 mW and 77%, respectively