Impact of gate driver signal on static losses for a SiC switch built with Normally-Off JFETs and a Schottky diode

Abstract

This document shows the behaviour of a SiC switch built with Normally-Off JFETs and a Schottky diode when the JFETs are controlled with a constant gate-to-source voltage or with a constant gate current. The JFETs are used in a direct and reverse conduction. The goal of this study is to determine a gate driver signal that minimizes static losses in the switch in spite of temperature variations. Two switches are tested: the first one is built with one JFET and one diode, the second one is built with four JFETs and one diode. It has been shown that in both cases, when reverse conduction is used, a current controlled gate driver leads to lower static losses.