The Effect of Dynamic On-State Resistance to System Losses in GaN-based Hard-Switching Applications

Gallium Nitride enhancement-mode high electron mobility transistors (GaN E-HEMTs) can achieve relatively high frequency and high efficiency, due to its excellent switching performance. In the meantime, dynamic RDS(on) has drawn significant attention from both academia and industry. In this paper, a modified double pulse test (DPT) setup is applied with soak time and junction temperature control. A quantitative analysis on RDS(on) from heating effect and trapping effect is conducted. A conduction loss equation based on two factors kTj and kdr is proposed. A system-level loss breakdown is conducted to show the percentages of each loss for GaN HEMTs. Compared to switching loss Eon, the loss contributed by dynamic RDS(on) has significantly less impact on the system efficiency.