In this white paper, we evaluate the surge robustness of a GaN FET-based Flyback power supply and demonstrate the maturity of GaN technology for adoption into high-volume markets. Unlike conventional silicon, lateral GaN FETs do not avalanche close to their rated voltage; instead, a robust transient overvoltage capability allows these devices to continue to safely switch through surge events.

Surge testing, based on the IEC 61000-4-5 and VDE 0884-11 standards, shows that GaN FETs survive surge events without any hard failure or change in converter efficiency. GaN FETs have been shown to switch safely with peak voltage over 800 V, and for tens of milliseconds – a condition that significantly exceeds the maximum continuous operating voltage rating of 650 V.