A novel package electrical characterization process-application on plastic BGA packages

A novel approach to a complete package electrical characterization process is presented. Two different plastic BGA packages are analyzed to illustrate this. The process begins by selecting a suitable electrical circuit model for study of the signal propagation path. Once the model is selected, the values for each of the circuit elements are computed using commercially available software (Ansoft/sup (R)/ & Pacific Numerix/sup (R)/). The electrical circuit model is used for preliminary product simulation and as a method to check for supplier conformity to package specification through verification using actual measurements. Package measurement using TDR and S-parameter techniques are carried out once the package is taped out. These measurement results are compared to those from modeling for validation. Corrections and adjustments are made to the package model for more accurate future package performance prediction. Finally, the limitations of the plastic BGA packages are summarized.