The EMC and signal integrity impact of printed circuit board (PCB) trace discontinuities, such as vias, where the signal is transitioned from one layer to another in the PCB stackup, have become significant recently with the use of very high speed signals in today''s systems. If these discontinuities are ignored, significant distortion of the high speed signal can occur, and in many cases, cause data errors. A fast and accurate technique to include the effect of via discontinuities in the typical design process is needed to ensure this distortion is considered if significant. Therefore, a simple equivalent circuit for the via discontinuity is needed so that this equivalent circuit can be easily used in the normal signal integrity analysis tools. This paper demonstrates the effect on the equivalent circuit values as the distance between the signal via and the return-current via is increased. Also, the frequency range where a quasi-static based equivalent circuit is accurate or where a full-wave model is required is shown for the various distances between vias.

Meeting Name

InternationalSymposium on Electromagnetic Compatibility, 2004


Electrical and Computer Engineering

Keywords and Phrases

EMC; PCB Trace Discontinuities; Electromagnetic Compatibility; Equivalent Circuits; Frequency Range; Full-Wave Approach; High Speed Signal; Model Accuracy; Printed Circuit Board; Printed Circuit Layout; Quasi-Static Approach; Signal Integrity Impact; Via Equivalent Circuit Model

Document Type

Article - Conference proceedings

Document Version

Final Version

File Type





© 2004 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

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