Recent achievements in the thermal characterization of electronic devices by means of boundary condition independent compact models

In this paper recent achievements in the thermal characterization of electronic devices by means of so-called 'compact models' are described. A 'compact model' is a simplification of a detailed model of a device. It is a simple network comprising a limited number of thermal resistances (typically 7), connecting the critical part of the device (usually the junction) to the outer parts of the device, is independent of the applied boundary conditions, and is capable of accurately representing the full model. This method of thermal characterization is suited for embedding in the design environments that are employed by the electronics industries, and the compact models can be incorporated into the component libraries linked to PCB thermal analysis software packages. A new methodology for deriving more or less 'standardized' compact models is presented. The possibility of creating parametric compact models, and the influence of differences in ambient temperatures, is discussed. It is demonstrated that the thermal behaviour of electronic devices by means of compact models can be approached within typically 6% of the detailed model values.