Bart McCoy, Senior Engineer, Mayo Clinic
Robert Techentin, Principle Engineer, Mayo Clinic
Ben Buhrow, Senior Engineer, Mayo Clinic
Kevin Buchs, Lead Engineer, Mayo Clinic
How T. Lin, Senior Advisory Technologist and TA of CTO,
Endicott Interconnect Technologies
Barry K. Gilbert, Director of the Special Purpose Processor,
Development Group, Mayo Clinic
Erik S. Daniel, Deputy Director of the Special,
Purpose Processor Development Group, Mayo Clinic

Variability analysis is important in successfully deploying multi-gigabit backplane printed wiring boards (PWBs) with growing numbers of high-speed SerDes links. We discuss the need for large sample sizes to obtain accurate variability estimates of SI metrics (eye height, phase skew, etc).

Using a dataset of 11,961 S-parameters, we demonstrate statistical techniques to extract accurate estimates of PWB SI performance variations. We cite numerical examples illustrating how these variations may contribute to underestimated or overestimated design criteria, causing unnecessary design expense. Tabular summaries of performance variation and key findings of broad interest to the general SI community are highlighted.