Uploaded March 2026 | Updated September 2026, 3 weeks ago
Altium Develop gives your entire PCB team real-time visibility into design, supply chain, and manufacturing so signal integrity decisions never happen in a silo: altium.com/develop?utm_source=youtube&utm_medium=video&utm_campaign=signal-integrity&utm_content=via-dispersion-why-propagation-delay-changes-with-frequency
In this follow-on tutorial, Zach Peterson dives deep into via dispersion — the phenomenon that causes propagation delay through a via structure to vary significantly as a function of frequency. Using Simbeor simulation data and Microsoft Excel, Zach walks through the math behind extracting propagation delay from both insertion loss and return loss S-parameter plots, and reveals why the values you get from each can differ dramatically depending on your operating frequency range.
If you're designing high-speed PCBs with DDR interfaces, differential pairs, or any channel requiring bandwidth above a few gigahertz, understanding via dispersion is critical. Zach explains why a via with a non-flat impedance spectrum will also exhibit a non-flat propagation delay curve — and what that means for signal integrity, eye diagrams, and bit error rates in your real-world designs.
👉 Resources from this video:
- What is Propagation Delay in High Speed PCB Design?: resources.altium.com/p/what-is-propagation-delay
- How to Input Via Delay in Altium for DDR Routing: youtu.be/o8orj7bN7Bo?si=MZZLMnraA7VhSydP
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Don't forget to like, comment, and subscribe for more in-depth tutorials and tips from @AltiumAcademy Share your thoughts and questions in the comments below!
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Don't forget to follow us on social to stay up-to-date on the latest Altium Academy content.
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The Altium Academy is an online experience created to bring modern education to PCB Designers and Engineers all across the world. Here you can access a vast library of free training and educational content covering everything from basic design to advanced principles and step-by-step walkthroughs. Join industry legends as they share their career knowledge, review real-life design projects, or learn how to leverage one of Altium's leading design tools. No matter your level of experience, the Altium Academy can help you become a better Designer and Engineer!
About Altium LLC
Altium LLC (ASX:ALU), a global software company based in San Diego, California, is accelerating the pace of innovation through electronics. From individual inventors to multinational corporations, more PCB designers and engineers choose Altium software to design and realize electronics-based products.
#Altium #SignalIntegrity #PCBDesign
0:00 Intro
3:12 Return Loss Plot Analysis
5:41 Simbeor Via Structure Review
8:23 Via Dispersion & Impedance
10:38 Propagation Delay Analysis
12:19 Return Loss Plot Analysis
13:55 Propagation Delay Curves
15:44 Via Design Considerations ️
17:15 Conclusion and Q&A
Altium Develop gives your entire PCB team real-time visibility into design, supply chain, and manufacturing so signal integrity decisions never happen in a silo: altium.com/develop?utm_source=youtube&utm_medium=video&utm_campaign=signal-integrity&utm_content=via-dispersion-why-propagation-delay-changes-with-frequency
In this follow-on tutorial, Zach Peterson dives deep into via dispersion — the phenomenon that causes propagation delay through a via structure to vary significantly as a function of frequency. Using Simbeor simulation data and Microsoft Excel, Zach walks through the math behind extracting propagation delay from both insertion loss and return loss S-parameter plots, and reveals why the values you get from each can differ dramatically depending on your operating frequency range.
If you're designing high-speed PCBs with DDR interfaces, differential pairs, or any channel requiring bandwidth above a few gigahertz, understanding via dispersion is critical. Zach explains why a via with a non-flat impedance spectrum will also exhibit a non-flat propagation delay curve — and what that means for signal integrity, eye diagrams, and bit error rates in your real-world designs.
👉 Resources from this video:
- What is Propagation Delay in High Speed PCB Design?: resources.altium.com/p/what-is-propagation-delay
- How to Input Via Delay in Altium for DDR Routing: youtu.be/o8orj7bN7Bo?si=MZZLMnraA7VhSydP
💡 Stay Connected:
Don't forget to like, comment, and subscribe for more in-depth tutorials and tips from @AltiumAcademy Share your thoughts and questions in the comments below!
👉 Subscribe for more: youtube.com/@AltiumAcademy?sub_confirmation=1
Don't forget to follow us on social to stay up-to-date on the latest Altium Academy content.
👉 Follow Altium on TikTok: tiktok.com/@altiumdesigner
👉 Follow Altium on Twitter: twitter.com/altium
👉 Follow Altium on Linkedin: linkedin.com/company/altium
👉 Follow Altium on Facebook: facebook.com/AltiumOfficial
The Altium Academy is an online experience created to bring modern education to PCB Designers and Engineers all across the world. Here you can access a vast library of free training and educational content covering everything from basic design to advanced principles and step-by-step walkthroughs. Join industry legends as they share their career knowledge, review real-life design projects, or learn how to leverage one of Altium's leading design tools. No matter your level of experience, the Altium Academy can help you become a better Designer and Engineer!
About Altium LLC
Altium LLC (ASX:ALU), a global software company based in San Diego, California, is accelerating the pace of innovation through electronics. From individual inventors to multinational corporations, more PCB designers and engineers choose Altium software to design and realize electronics-based products.
#Altium #SignalIntegrity #PCBDesign
0:00 Intro
3:12 Return Loss Plot Analysis
5:41 Simbeor Via Structure Review
8:23 Via Dispersion & Impedance
10:38 Propagation Delay Analysis
12:19 Return Loss Plot Analysis
13:55 Propagation Delay Curves
15:44 Via Design Considerations ️
17:15 Conclusion and Q&A
