Delphi-like Boundary Condition Independent (BCI) Compact Thermal Models (CTMs) are the standard for modelling single die packages. However their extraction, particularly in the transient case, will be time consuming due to complex numerical simulations for a large number of external conditions. Lately, new approaches to extract a BCI Dynamical CTM (DCTM), based on Model Order Reduction (MOR) have been developed. Despite the numerous advantages of this recent method, the lack of numerical tools to integrate reduced-order models (ROM) makes it difficult to use at board level. In this study, a novel process flow for extracting Delphi-inspired BCI DCTMs is investigated. Thus a detailed three-dimensional model is replaced by a BCI-ROM model using FANTASTIC matrix reduction code to generate the data used in the creation of a Delphi-style BCI DCTM. That hybrid reduction method has been applied to an industrial single-chip package, named QFN16. Its derived CTM and DCTM have been compared in term of accuracy and creation time for both approaches: in-house Delphi-inspired and MOR based. The results show that for a similar accuracy, the integration of MOR technique allows minimizing the time-consuming numerical simulations and so to reduce the thermal network creation time by 80%.

Planar Magnetic Components are new alternatives to classic transformers. Based on the combination of a low profile high frequency magnetic core and a Printed Circuit Board, these devices allow large reduction in terms of weight and size, which exacerbates power density constraints. To circumvent the potential issues of a multi-layer embedding of flatten high-current-density copper windings at the heart of a substrate, a set of analyses were conducted to characterize electro-thermo-magnetic combined effects with the purpose of elaborating a pertinent thermal model. Using a set of numerical simulations, several concepts of multi-source surrogate thermal model were derived with the prospect of shortening the expensive computation time of the fine Detailed Thermal Model. These approximated models permit to monitor the sensitive temperatures of the primary and secondary windings as well as core ones. Designers can therefore perform trivial calculations to analyse the thermal behaviour of planar transformers for various boundary conditions.