Facilitation of GaN-Based RF- and HV-Circuit Designs Using MVS-GaN HEMT Compact Model

This paper illustrates the usefulness of the physics-based compact device models in investigating the impact of device behavioral nuances on the operation and performance of the circuits and systems. The industry standard MIT virtual source gallium nitride high electron-mobility transistor (GaN HEMT) (MVSG) model is used as the modeling framework to understand the operation of the GaN HEMTs and study the key device-circuit interactions in the GaN-based high-frequency and power conversion circuits. Details of the core model equations along with their physical underpinnings are presented along with the benchmark tests to verify the model's convergence robustness and simulation accuracy. The usefulness of such a compact model in circuit design is highlighted through examples of the GaN-based high-voltage converter and RF-power amplifiers. It is shown that the slew-rates in hard-switched buck converters are determined by the dynamic charge distribution among the field plates in GaN HEMTs, indicating the importance of the device-level effect on circuit performance. Likewise, it is shown using the MVSG model that the performance metrics, such as drain efficiency and linearity, of the GaN RF-power amplifiers are heavily dependent on the device-level effects, such as access-region depletion, thermal effects, and charge-trapping effects. These GaN-based circuits designed using the MVSG model can be used as the example cases to demonstrate the importance of the accurate physical compact models in designing high performance circuits and systems in emerging technologies.