PWM power cycling of a multichip power module with active die tem- perature equalization

Abstract:
The massive parallelization of power dies is necessary for achieving high current capabilities in applications such as wind and traction. In such application, the reliability is a key factor to reduce the maintenance time and cost s. Nonetheless, electrical and thermal mismatches between the parallel dies leads to unequal die deterioration which conduces to a system lifetime derating compared to the individual die’s lifetime. In this paper, the temperatures of the parallel power dies are equalized thanks to a temperature feedback in order to avoid premature failures and thus increase the lifetime of multichip power modules. An advanced power cycling platform is built to measure the lifetime gains of this approach. Furthermore, physical analysis were conducted in order to demonstrate the lifetime balance in respect to the solder layer.