Study of PCB Trace Crosstalk in Backplane Connector Pin Field

PCB traces in backplane are typically routed as striplines, which create near end crosstalk, but theoretically, no far end crosstalk. However, in practice, both near end and far end crosstalk introduced by via antipads and layer misalignment in the connector pin field due to manufacturing process variations can be significant. This paper presents an analysis for the first time of the PCB trace crosstalk in the connector pin field of high speed backplanes. Crosstalk from the adjacent differential pairs on the same layer and in particular, from neighboring layers is first modeled and simulated with the consideration of PCB design tolerances and routing constraints in the connector pin field. The model is then correlated with a 10ps edge TDR measurement. Finally, the simulated and measured results are provided to demonstrate the significance of the crosstalk due to connector pin field traces.