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Failure Dynamics of the IGBT During Turn-Off for Unclamped Inductive Loading Conditions



Chien-Chung Shen, Allen R. Hefner Jr., David W. Berning, J B. Bernstein


The internal failure dynamics of the Insulated Gate Bipolar Transistor (IBGT) for unclamped inductive switching (UIS) conditions are studied using simulations and measurements. The UIS measurements are made using a unique, automated nondestructive Reverse Bias Safe Operating Area test system. Simulations are performed with an advanced IGBT circuit simulator model for UIS conditions to predict the mechanisms and conditions for failure. It is shown that the conditions for UIS failure and the shape of the anode voltage avalanche sustaining waveforms during turn-off vary with the IGBT temperature, turn-off current level, and load inductance. Evidence of single and multiple filament formation is presented and supported with both measurements and simulations.
IEEE Transactions on Industry Applications


automatic tester, avalanche, failure, IGBT, model, RBSOA


Shen, C. , Hefner Jr., A. , Berning, D. and Bernstein, J. (2000), Failure Dynamics of the IGBT During Turn-Off for Unclamped Inductive Loading Conditions, IEEE Transactions on Industry Applications, [online], (Accessed July 22, 2024)


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Created February 29, 2000, Updated October 12, 2021