Analysis of GaN HEMT switching behavior

This paper presents a comprehensive study of the GaN HEMT switching performance in a phase-leg configuration with special focus on the impact of different parasitic effects. Therefore, a simulation model of a double pulse test circuit with GaN devices and including parasitic elements is proposed. The causes of parasitic inductances and capacitances are discussed and their effects are analyzed. Furthermore, the influence of the gate resistance value and dead time is investigated. A double pulse tester was designed to experimentally verify the simulation results. This paper shows the switching transients of both devices in a phase-leg configuration for varying parameters graphically and offers a better insight into the switching behavior of GaN transistors. The understanding of the parasitic effects and varying parameter enables improved design and performance of fast switching power converters.