Impact on Signal Integrity and Radiated Emissions of Two-Layer vs Four-Layer BGA Package Technology for Automotive Applications

In the context of Ball Grid Array IC-packages development, the reduction of the number of layers is often requested for cost minimization reasons. For low-end applications running in at frequencies below 1 GHz, a two-layer package implementation can be considered, with the drawback of a potential performance degradation. To prevent the product failure, it is fundamental to predict and contain this degradation with the support of electrical simulations. This paper compares a two-layer package substrate with a four-layer one, by applying a complex simulation flow that includes S-parameters, time-domain signal integrity analysis, evaluation of AC currents distribution and radiated fields estimation.