Voltage dependence of self-clamped inductive switching (SCIS) energy capability of IGBTs

Self-clamped inductive switching (SCIS) energy capability is the most important device parameter for insulated gate bipolar transistors (IGBTs) used in automotive ignition applications. We have experimentally characterized the dependence of IGBTs SCIS energy capability on the clamp voltage for an ambient temperature range of -50 to 175/spl deg/C. It is found that the SCIS energy of an IGBT increases by nearly 70% when the clamp voltage is reduced from 400 to 100 V. Such a significant increase is attributed to the lower maximum junction temperature that is reached in an IGBT with a lower clamp voltage during the SCIS testing. Two-dimensional (2-D) electrothermal device simulations have been performed to analyze such phenomena. The results provide critical information for device design and product development.