Dynamic electro-thermal modeling for power device assemblies

Abstract This paper reports on the development of a hybrid approach to electro-thermal modeling of power device assemblies, suitable for reliability-oriented thermal design of power modules and converters. The temperature-dependent electrical model of a power MOSFET is self-consistently coupled with a dynamic lumped-element thermal network representing the die – package – heat-sink assembly and convective boundary conditions. The lumped-element network elements are calculated on the basis of geometrical dimensions and materials physical characteristics. The results of the lumped-element model are compared with thermal measurements in both steady-state and transient conditions. The model is compared with measurement result over an extended time scale, ranging from microseconds to tens of minutes.