Characterization of SenseGaN current-mirroring for power GaN with the virtual grounding in a boost converter

This paper presents an implementation of the SenseGaN current sensing technique using Gallium Nitride (GaN) transistors as a representative of Wide Bandgap (WBG) semiconductors. For effective feedback control, fast over-current protection, and diagnostics-prognostics developments, precise current measurement becomes more important. While the integration and miniaturization of power semiconductors are getting more feasible to operate at higher current as well as switching frequency, most of the available current measurement techniques have some technical challenges such as bandwidth limitations, higher power dissipation, and sensitivity variations. SenseGaN technique along with the integration of semiconductors to monitor the power module current without significant effects on power stage performance and opens a new era for smart devices in future power electronics; however, in practice, implementation of this method has some difficulties that should be addressed during the design process. This paper presents of SenseGaN in WBG-based power converters with Spice simulations and mathematical analysis. Finally, a prototype using power 650V-GaN is successfully tested at 150kHz, and verifies the consistency with the proposed model.