On the Importance of Appropriate Current Probes for Double Pulse Tests and How to Select Them

Abstract:
Wide Band Gap power semiconductors require highly precise and low-intrusive measurement equipment to accurately measure their switching losses. The solutions developed for the characterization of Silicon power semiconductors have been proven to be too intrusive or to provide insufficient accuracy, leading to inadequate measurement results. In recent years, there have been several novel developments for sensors applied in Double Pulse Tests that aim to address key issues, warranting a comprehensive method to select a sensor that fits to the task of measuring fast transient signals. This paper proposes such a method, and presents a tool to quickly identify the estimated influence of sensors on the device behaviour. Moreover, it is advised that comparisons between sensors should not be based solely on the data sheet values (e.g. bandwidth and maximum current), as discrepancies in transmission behavior and definitions can result in the generation of misleading data, providing a false sense of security. In practice, the actual measurement behavior must be taken into account. This paper highlights these issues and develops a methodology which can minimize their impact on data quality.