Modelling jitter induced by fibre weave effect in PCB dielectrics

Abstract

Dielectric properties of Printed Circuit Board (PCB) glass weave re-enforcement can differ greatly from the properties of the resin matrix due to processes inherent in the engineering of dielectric substrates. This inhomogeneity can contribute to increases in skew and deterministic jitter at data rates of 10 Gbps and higher for paired transmission lines routed on typical PCB materials. This paper proposes a new model for accurately characterizing the glass weave-induced skew and jitter in PCB substrates. This new model will be used to predict the package-level performance of existing and next-generation skew mitigating laminate materials. The model provides guidance for PCB material selection on the basis of skew/jitter estimates for the corner cases.