Latest Posts

Simulating Serial Link Compliance

Author: Donald Telian, SI Guys - Guest Blogger Simulating a serial link typically involves confirming compliance with one of the many Serial Link Standards. PCIe, SATA, XFI, CEI, SFP+, USB, KR4, and so on. With over a dozen common standards - each with their own compliance nuances - this feels like it could be a vast and complex topic. Indeed, it takes a full-day class to address only the most popular standards. While serial links is the clear winner in signaling methods, there is no clear winne...

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Donald Telian, SiGuys - Guest Blogger 3/9/2020 Comments(0)

Serial Link Equalization Primer

Author: Donald Telian , SI Guys - Guest Blogger Equalization is powerful. SerDes Serializer-Deserializer Equalization has enabled data rates we would not have thought possible, and it continues to be the secret sauce of serial links. While good performance depends on doing basic things in hardware Steps 1 to 6 , it is arguably the configuration of SerDes Equalization Settings SES, Step 7 that determines eye margins - as illustrated in Fixing Signal Integrity Issues in Software . As such, SI an...

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Donald Telian, SiGuys - Guest Blogger 1/14/2020 Comments(0)

Understanding Connector and Package Impedance

Author: Donald Telian , SI Guys - Guest Blogger I've grown accustomed to viewing passive interconnect as the road signals drive on. Impedance discontinuities appear as the speed bumps or potholes that make the ride bumpy and unpleasant, if not slower. Perhaps I've looked at too many TDR plots ? For many years our industry has been well-tooled to understand and manage PCB trace impedance , which continues to define the majority of the "road" signals travel on. Over time higher data rates have c...

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Donald Telian, SiGuys - Guest Blogger 12/9/2019 Comments(0)

On Exercising Engineering Judgment

Author: Donald Telian , SI Guys - Guest Blogger Signal Integrity Engineering requires Engineering Judgment. The same thing that makes SI require Creativity causes it to also require above average Judgment; namely that you will consistently be asked to craft clear answers from insufficient data based on ill-defined measures of success. There’s no way around it, Engineering Judgment Required. So we’ll address this topic here in our mini-series on the soft skills required for Signal I...

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Donald Telian, SiGuys - Guest Blogger 11/8/2019 Comments(0)

On Working WITH Your Layout Engineer

Author: Donald Telian , SI Guys - Guest Blogger I have a distant cousin who spent his career doing high-speed PCB layout. At a family gathering we were learning what each other did for a living, and when he learned I’m in Signal Integrity he looked at me warily. I was one of those guys. He then shared how we was going crazy routing, re-routing, and re-routing a high-speed PCB because an SI Engineer was giving him constraints that were impossible to meet. Lots of time wasted, and he was c...

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Donald Telian, SiGuys - Guest Blogger 10/8/2019 Comments(0)

What is Signal Integrity?

Author: Donald Telian , SI Guys - Guest Blogger Great question. Now that I've devoted well over 30 years to the field, I'll venture an answer. My simplistic definition has always been "the analog side of digital". I still like that description, because in practice the binary world of "ones" and "zeroes" only exists in theory. And, hopefully, in system memory - assuming the interface's Signal Integrity SI was done correctly. My answer to the question will describe Signal Integrity from angles not...

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Donald Telian, SiGuys - Guest Blogger 8/5/2019 Comments(0)