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In more than 30 years of teaching signal integrity, I find the most confusing topic for engineers, even those working in the field for years, is the question of what is the impedance of a transmission line?  Read on to learn about the 5 types of impedance.

As Dave Dunham from Molex Corp. likes to say, "When designing high-speed serial links beyond 10 GB/s, everything matters." In order to ensure first time success at these speeds, accurate channel modeling is a prerequisite. This is especially true for long backplane channels.

Microwave engineers know that sharp corners and right-angle bends have their drawback at high frequencies. So what happens if we go to the other extreme of the spectrum, to DC? Istvan Novak takes a closer look.

We have to use enough capacitors so that the PDN functions properly. At the same time, to keep cost and size in check, we want to avoid overdesign and not use capacitors unnecessarily. Read on for advice on how to find the balance.

We worry about via stubs in high-speed designs because they cause unwanted resonant frequency nulls which appear in the insertion loss plot (IL) of the channel. But are all via stubs bad? Well, as with most answers relating to signal integrity, “It depends.”