Reliability of power MOSFET-based smart switches under normal and extreme conditions for 24 V battery system applications

This study aims to assess the reliability of smart converters for applications using 24 V batteries. It compares degradation effects and lifetime durations for similar dissipated energies when these smart power switches are subjected to normal and extreme protection test conditions. Three experimental ageing tests have been performed: (i) ageing tests under normal protection mode, (ii) ageing tests under repetitive inductive avalanche switching and (iii) ageing tests under repetitive short-circuit. Evolution of several electrical parameters such as on-state resistance; threshold voltage and saturation current have been monitored. Tested devices under normal condition and under repetitive inductive avalanche have failed after about the same number of cycles with the same dissipated energy. However, several results show a significant decrease of the lifetime under repetitive short-circuit tests for a similar dissipated energy.