Single Gate-Drive GaN Power Electronics Building Block for Scalable and Fast-Switching High-Current Systems

This work presents a single gate-drive GaN power electronics building block for scalable high-current systems for dc/dc or dc/ac-conversion based on 100V,7mΩ Schottky GaN transistors. By utilizing a dedicated gate-booster for each transistor (fits within the GaN footprint) maximum switching speeds, low switching losses and improved low load efficiency are achieved. Double-pulse measurements at 48V show identical behavior of the four parallel GaNs with identical switching losses within the measurement accuracy of ≈10% (turn-on) and ≈20% (turn-off), gate voltage waveforms with a worst-case time offset of ≤600ps (turn-off) and 320ps (turn-on) and similar undershoots. Furthermore, the current sharing between the four paralleled GaN transistors is evaluated in double-pulse tests by characterization and simple modeling of the transfer characteristic of each transistor and accurate gate-source and drain-source voltage measurement, showcasing the applicability of the single gate-drive concept.