Technical Articles

Comparing Embedded Coplanar Waveguide and Stipline for Multi-Layer Boards

It is important in high-speed digital applications to decrease the form factor and increase signal density by reducing isolating metal layers, all while preserving comparable crosstalk, loss and dispersion at the frequency of interest. This paper takes a look at how you can do that by showing how coplanar waveguide with smaller form-factor outperforms stripline in isolation and coupling.

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IEEE P370: A Fixture Design and Data Quality Metric Standard for Interconnects up to 50 GHz

The fixtures used to characterize interconnects in complex systems can have a significant effect on the measured data, read on to get the background and perspective on IEEE P370. Check out this Outstanding Paper Award Winner from EDI CON USA 2018.

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PAM4: For Better and Worse

Is PAM4 worth the hassle?

That’s the question that will trigger your amygdala’s fight or flight response as you encounter the many annoyances that PAM4 brings to your world. Since you’re in a lab rather than a jungle, that fight or flight response might translate into sarcastic cracks like: “Right, that higher BER requirement makes it all so much easier—not.” “Good old NRZ, those were some fine bits. Remind me why I asked for this?” And, “dear NRZ, I never knew how much I loved you until I lost you.”

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Demystifying Edge Launch Connectors

A particularly challenging configuration is the edge launch, where connectors are used on the edge of the PCB with a transition to a microstrip trace. A poorly optimized connector footprint leads to degradation of the signal integrity performance, especially at high data rates. This paper identifies the root cause of the problem by showing how the electromagnetic fields behave at the transition area. Then it presents a design methodology, using simulated and measured data, that ensures the quality of high-speed data transmission.

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Avoid These Two Artifacts When Measuring SMPS Power Rails

Switch-mode power supplies (SMPS) are commonly used DC-to-DC converters in many electronic components. By their nature, they can generate a lot of radiated emissions. Unless care is taken, it is difficult to separate what is the actual voltage on the power rail and what is an artifact due to the way we probe the circuit. The project outlined here shows how to avoid EMI pick-up and cable reflection noise.

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