A general method for the connection of a component thermal model to a board

In this paper, a generalized method for the connection of a thermal component model in board- and system-level thermal simulations is presented. The method allows for the definition of uniform heat flow connections as well as the standard uniform temperature interface regions. The use of uniform heat flow ports will be shown to better handle cases where large temperature gradients are present in the base model. The two methods of connecting the component model will be evaluated using two different models. First, a simple example will be presented to illustrate the nonphysical behavior introduced by the use of uniform temperature connections. Second, a model of an electronic package will be used to evaluate the relative merits of the two connection methods with respect to board thermal conductivity and boundary conditions present on the board and the package. It will be shown that the results from use of uniform heat flow connections are generally better than from use of uniform temperature regions with respect to predicting junction and board temperatures.