Optimal Dead Time Selection in GaN FET Switching Leg Via Thermal Analysis

Correct dead time selection is crucial in Gallium Nitride (GaN) devices having a significant impact on the overall performance, efficiency, and reliability of power electronic systems. Incorrect dead time selection can cause a variety of issues, including increased power losses, reduced efficiency, and increased device operating temperatures. This paper investigates the impact of dead time on the operating temperature of GaN devices employed in hard-switching converters. A measurement methodology where the dead time is selected to minimize the operating temperature of the hottest switch is proposed. Optimal dead time as a function of the device current is experimentally derived. Obtained data are discussed by comparing the optimal thermal derived dead time with the measured switching catachrestic of the device.