Surge-Robust Flyback Power Supplies with GaN

摘要

In this paper, we have evaluated the surge robustness of a GaN FET-based Flyback power supply and demonstrated the maturity of GaN technology for adoption into high-volume markets. While the present generation of lateral GaN FETs do not have the capability to avalanche, significant transient overvoltage capability allows these devices to switch through surge events. Surge testing was based on the IEC 61000-4-5 and VDE 0884-11 standards, and we have shown in this work that GaN FETs survive the surge events without any hard failure or change in converter efficiency over 90VAC - 264VAC line conditions. GaN FETs have been shown to switch through with peak voltage over 800V, and for tens of milliseconds while exceeding the maximum continuously operating voltage rating of 650V. We have also demonstrated that GaN FETs can operate under momentaneous line voltage swell conditions per IEEE Standard 1159-2009 without suffering any degradation in converter efficiency. Such robustness enables the wide-spread adoption of GaN in cost-sensitive consumer electronics applications.