Physics-based analytical model for high-voltage bidirectional GaN transistors using lateral GaN power HEMT

A bidirectional switching GaN transistor, PCB-packaged using commercially available high voltage power GaN HEMTs (200V, 3A) from EPC, has been modeled and characterized. A physics-based FET model, originally developed by Statz for short-channel GaAs MESFET, has been adapted to model both static and switching characteristics of both the constituent HEMT and the bidirectional switch up to 125°C. We have found that the Statz model is superior to conventional short-channel MOSFET models due to the mixed pentode-triode on-state I-V characteristics of the EPC GaN HEMT. The bidirectional GaN transistor exhibits linear operation as well as bidirectional current saturation, offering low on-state resistance along with current limiting capabilities.