Influence of Paralleling Dies and Paralleling Half-Bridges on Transient Current Distribution in Multichip Power Modules

This letter addresses the transient current distribution in the multichip half-bridge power modules, where two types of paralleling connections with different current commutation mechanisms are considered: paralleling dies and paralleling half-bridges. It reveals that with paralleling dies, both the high-side and low-side paralleled devices experience a similar transient current imbalance due to the mismatched stray inductance. However, with paralleling half-bridges and with the same mismatched stray inductances, the high-side paralleled devices have much smaller transient current imbalance, the cause of which is found be to the current commutation process. Theoretical analysis based on the circuit modeling and current commutation process elaborates the findings, which are then confirmed by experimental results.