Analytical solution for temperature distribution of power semiconductor devices mounted on rectangular base plate

Thermal performance is a major design consideration for power electronics systems. Power semiconductor devices are temperature limited and to satisfy application reliability considerations it is necessary to limit the junction temperature during operation through design. Hence it is desirable to have a procedure that can accurately calculate the temperature distribution of the system under actual operation conditions. This paper presents an analytical technique that estimates the temperature distribution of devices mounted on rectangular base plates without the lengthy computation required by finite element analysis (FEA). The procedure enables the designer to estimate the temperature distribution due to power dissipation on the base plate which could be heat sinks or printed circuit board, and to utilize this information to optimize the number of devices and their layout. This procedure can also be used to evaluate different cooling solutions to meet system level objectives, e.g. size and cost.