With the increasing demand for power converters and high power densities, and Silicon (Si) is reaching its theoretical limits, Silicon Carbide (SiC) is the object of a growing interest. It possesses several advantages over Si, among which: lower on resistance and operation at higher temperatures . This makes of SiC transistors, and more generally SiC power converters , the ideal candidates for use in hybrid and electric cars. Only one type of SiC transistor is close to commercial production: the Junction Field Effect Transistor (JFET). However, it is a normally- on device, i.e. it needs a negative voltage to be turned off. Therefore it needs protection when used in a circuit, as a fault in the driver power supply would turn on the JFET and possibly lead to short-circuits .
The invention proposes a way of solving the problem while retaining the advantages of using a SiC transistor. Therefore it does not add switching losses and does not impede the high temperature operation.

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