Measuring the effects of energy flow on IC package thermal performance

This paper is an examination of how to model PCB conduction effects when modeling IC package thermal performance. It compares finite element models of electronic packages to package on board measurements to packages on a board simulator using a power dissipation control structure. The paper presents measurement data showing the change in junction temperature compared to the amount of heat conducted through the leads of a package. It suggests a simple model for representing this phenomena where the total energy being dissipated through the package is broken into two directions, convection in the upward direction of the package and conduction through the bottom of the package