A comparative study of the performance of compact model topologies and their implementation in CFD for a Plastic Ball Grid Array package

A detailed model of a die-up 256-pin Plastic Ball Grid Array (PBGA) package was created and validated against experimental data for natural convection and forced convection environments. Next, four compact models were derived ; two two-resistor models (one created through a two-point computational co ld plate test: the other using the DELPHI optimization approach), a multi-r esistor Star network model and a shunt network model. The latter three mode ls were derived using the methodology established by the DELPHI (Developmen t of Libraries of Physical models for an Integrated design environment) pro ject, The four compact models and the detailed model were each placed in na tural convection and forced convection (velocities of 1,2, and 4 m/s) envir onments. Good agreement was obtained for the die-junction temperature rise for both the detailed and the shunt compact models. The star and two-resist or models were seen to be inferior in terms of accuracy. The two-resistor m odel created using the DELPHI methodology was found to be superior compared to the one created with the computational cold-plate test. The star model showed little gain in performance as compared to the DELPHI two-resistor mo del.