| Abstract |
Turn-off ringing is a challenge caused by parasitic elements in power loop, resulting in switchinglosses, voltage breakdown and EMI issues. A worse case occurs while employing wide bandgappower transistors due to their fast turn-off. The conventional way to mitigate turn-off ringing isto reduce the commutation loop inductance or slow down transistors' switching speed. However,slow turn-off speed is undesirable due to low switching loss. In this work, it is demonstrated thatfast turn-off of wide bandgap(WBG) transistors can facilitate minimizing voltage overshoot withwell-tuned parasitic loop inductance. Based on the characterization of the turn-off transition,an analytical model is derived that shows voltage overshoot can be reduced without sacrificinglow turn-off loss and simple PCB layout while allowing high loop inductances. The proposedtechnology can fully exploit the potential of wide bandgap transistors in extremely fast switchingconditions. |
