Study on GaN FET Short Circuit Characteristics and Development of Effective Short Circuit Protection Method

GaN HEMTs are being used in power conversion systems due to their fast switching characteristics. While it is possible to achieve high efficiency and power density due to fast switching, GaN HEMT-based power converters have difficulties in practical protection in short circuit and overcurrent situations due to fast switching. In this paper, we analyze the characteristics of GaN HEMT according to the occurrence of short circuit and propose a short circuit protection circuit for GaN HEMT. The method used was to detect the drain-source voltage to check for a short circuit in the circuit and quickly turn off the device through a comparator circuit. The time taken for short circuit protection is 165ns, resulting in effective protection against short circuit scenarios.