A simple, low cost gate drive method for practical use of SiC JFETs in SMPS

The silicon carbide JFET has many promising advantages over silicon. However it requires a more complicated gate drive than conventional MOSFETs. In this paper a simple and effective method of driving the new devices with existing monolithic gate drive circuits is proposed. The basis of the proposed method lies in applying a constant negative DC bias to the gate in order to minimize the required voltage swing on the gate to enable switching to take place. The method is supported with experimental data and proves to be effective. The negative gate bias does however lead to additional losses and derating of the device is required. The derating data for a constant power loss is given as well