Thermal simulation and analysis of WBBGA packaging High-end Relay Protection Chip

Abstract

The package of the High-end Relay Protection Chip is Wire Bonding BGA (WBBGA) with 257 inputs/outputs (I/Os). This paper investigated the thermal performance of the High-end Relay Protection Chip using a computational fluid dynamics (CFD) tool. Firstly, according to the initial thermal simulation results, the junction temperature of the package was 115.29 °C appeared on the Relay Protection chip as the environment temperature was 25 C. Then a parametric study was performed to investigate the junction temperatures. We analysed the influence of different parameters on the thermal performance, including Via count, Via coating thickness, Substrate area, Copper coating rate of substrate, Printed Circuit Board (PCB) area, Heat transfer coefficient of epoxy molding compound (EMC) and die attach (DA). Finally, an orthogonal experiment was designed. It’s found that the heat transfer coefficient of DA was the most significant factor on the thermal performance by variance analysis, in addition, an optimal collocation of the package structure and material parameters was obtained by range analysis. The junction temperature of the optimal package was reduced to 95.69 °C by 17%. The results of these simulations give a reasonable indication of how the package would perform in a Relay Protection equipments