Abstract

The coupling of power dissipation and temperature is well known in electronics, yet electrothermal effects are rarely considered in the architectural stage of new product design. Incompatibilities between thermal and electrical design tools, and a lack of an electrothermal model supply chain, have proven to be effective barriers to electrothermal analysis in early stage design. A common issue in early thermal design with computational fluid dynamic (CFD) tools is simulating with worst case steady-state power values, and with little or no information about transient power sequencing for even the dominant operational functional goals of the product. The delayed availability of reliable power values often produces over-designed, expensive thermal solutions, or relegates thermal design to a remedial task. On the electrical side, it is common to simulate conceptual circuits with an isothermal assumption. By definition, this means operational temperature impacts on electrical performance are not captured. Temperature related issues with signal timing, current spikes, power levels, control systems, etc. could easily be missed or caught late in the process necessitating expensive re-designs. In order to address these issues, accurate thermal capabilities need to be introduced early in design areas that have traditionally been solely in the realm of electrical engineering. This has not been possible previously as thermal is very much a 3D domain while EDA tools are dominated by 1D toolsets. To bridge this divide, this presentation will illustrate how to leverage the FANTASTIC reduced order model extraction method to convert 3D thermal simulation models into BCI-ROMs in the IEEE standard VHDL-AMS format, and then connect them to form accurate electrothermal circuits in 1D tools. This approach enables power dissipation and other electrical parameters to solve concurrently with temperature, improving the understanding of in-situ product performance earlier in the design process, and ultimately enabling higher quality products to be designed.