Characterization and modeling of a gallium nitride power HEMT

In this paper, a simple and accurate circuit-simulator compact model for gallium nitride (GaN) high electron mobility transistor (HEMT) is proposed and validated under both static and switching conditions. A novel feature of this model is that it is valid also in the third quadrant, which is important when the device operates as a freewheeling diode. The only measurements required for the parameter extraction are simple I-V static characteristics and C-V characteristics. A double-pulse test-bench is built to characterize the resistive and inductive switching behavior of the GaN device. A simulation model is built in Pspice software tool, considering the parasitic elements from associated with the PCB interconnections and other components (load resistor, load inductor and current shunt monitor). The Pspice simulation results are compared with experimental results. The comparison shows good agreement between simulation and experimental results under both resistive and inductive switching conditions. Operation in the third quadrant under inductive switching is also validated.