Skip to main content

Differential Pair Routing for Signal Integrity and EMI

Published Date
Author Kirsch Mackey

Route high-speed differential pairs with better signal integrity and lower EMI. Learn stackups, impedance control, Allegro X constraints, routing, via design, and fixes for skew and crosstalk.

Download PDF

This practical design guide explains how to route high-speed differential pairs for reliable signal integrity and reduced EMI in modern PCB layouts. It covers stackup planning, differential impedance control, constraint setup in Allegro X PCB Layout, routing strategy, via design, and return path management, with clear guidance on how each choice affects high-speed performance. The guide also outlines how to identify and fix common issues such as skew, mode conversion, via stubs, and crosstalk, and shows how to use Sigrity X Aurora to validate differential pair quality before tapeout.

About the Author

Kirsch Mackey is an electrical engineer, educator, and content creator with over 15 years of experience spanning power systems, control systems, electrical systems, embedded programming, PCB design, power electronics, and high-speed digital systems. As founder of HaSofu and former adjunct professor, he developed the MESH method—a structured approach to high-speed PCB design that has helped students land roles at companies like Apple, Intel, Cisco, Garmin and Amazon in months rather than years. Drawing from industry experience at Intel and beyond, Kirsch bridges theory and practice through technical writing, courses, and hands-on workshops that make complex engineering concepts accessible and actionable.

Profile Photo of Kirsch Mackey
Follow on Linkedin More Content by Kirsch Mackey