The mission profile: a tool that is used for predicting the lifetime of a particular power module has been developed by Danfoss Silicon Power

摘要

An integrated power module is a vital component for any advanced traction-, drive-, or power-management application in road vehicles. Unfortunately, the physical environment in typical automotive applications is most hostile for the power module. Obituaries for deceased power modules make sad reading, and power module manufacturers do what they can to avoid premature passing away of their products They want to eliminate the causes of death and assure customers that the power modules will live forever - or at least as long as the customer specifies. The largest power module killer is simple variation of temperature, such as daily temperature variations in the environment and temperature cycles occurring inside the power modules during operation. Power modules constitute an assembly of different materials that have quite different physical properties. A sandwich of dissimilar materials, such as copper and ceramics or aluminum and silicon, will experience stresses and strains during temperature variations due to differences in the coefficient of thermal expansion (CTE) between the materials. These stresses and strains will inevitably cause fatigue cracking and delamination of sandwiched materials - they literally fall apart, as the temperature varies - and the power modules will die.