Calorimetric Measurement of Wide Bandgap Semiconductors Switching Losses

The fast switching of wide-bandgap semiconductors makes it challenging to measure their switching losses exactly. In order to receive accurate results with the double-pulse test, a time delay error between the measured voltage and current has to be corrected very precisely. Since the real values are not known, a calorimetric method was developed to verify the results of the double-pulse test. Switching loss measurements with both methods were conducted for a gallium nitride transistor. By comparison, it can be observed that the results of the calorimetric measurement stay within the expected maximum deviation of the double-pulse test which recommends this method as an alternative.