Compact Thermal Models: A Global Approach

Abstract

Construction and usage of compact thermal models (CTM) for the thermal analysis as well as the design of cooling devices for electronic systems are reviewed. These models have many advantages over the so called detailed models, mainly being a convenient and simple quantitative description of the modeled object, when constructional details are either unavailable or too detailed to be of use at the desired level of analysis. However, CTMs have manifested some deficiencies in many cases, in particular MCM and stacked dies. The opposite approach, detailed modeling, is more reliable, although extremely heavy. A new approach is proposed that solves this dilemma by bridging the gap between compact and detailed models. While retaining all advantages of CTM's, i.e. having a limited number of degrees of freedom and not requiring detailed constructional details, it can attain any required precision level depending on the degree of complexity adopted. It gives reliable results covering all operating conditions including MCM and stacked dies. Moreover, it gives access to data on surface temperature gradients that were never obtained before by compact models and are highly important for reliability issues