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Donald Telian discusses the nature of collaboration between signal integrity engineers and layout engineers, reflecting on how cooperation can be enhanced to promote teamwork, problem-solving, and productivity. 

Crosstalk problems here to stay as long as interconnects are designed as the open waveguiding systems. Thus, understanding and proper quantification of the crosstalk and mitigation of the consequences are important. This article outlines multiple possible ways to quantify the crosstalk: coupling coefficients, frequency domain metrics, time-domain analysis of crosstalk, and a modern statistical approach. 

When designing circuit boards, a change made to one aspect of the design intended to resolve an issue can cause problems elsewhere. To reduce the problem of soldering on SMA connectors in an edge launch, a significant signal integrity problem has been introduced. This article explores best practices and provides insight into avoiding an inadvertent mistake.

Intra-pair skew is a crucial metric when working with multiple lines. Its behavior, measurements, and interpretations are closely linked to other forms of signal degradation, making the definition of a single skew value a nuanced issue that requires careful consideration. In this article, Gustavo Blando and Prashant Pappu introduce three distinct methods for measuring skew, providing options for a wide variety of contexts and skew measurement goals.

In this article, Steve Sandler presents three viable solutions for measuring ultra-low impedance with a maximum of 10 ms, each of which can be performed using sophisticated and novel FFT based 3-port measurement. These methods involve applying digitally modulated patterns to create modulated load currents up to 1500 A and recording the resulting power rail voltage perturbations. 

Channel operating margin (COM) is a well-documented IEEE standard that has been used successfully since 2014 in the design of channels and specification of interconnect. In this article, Rich Mellitz reflects on the COM origin story and considers the future of the standard.

DesignCon gears up to celebrate its 30th anniversary this January with special events, an expo full of leading suppliers, and its highly regarded education.

EM simulators that are optimized for PCB PDN simulations provide an increased level of automation to enable the basics of DC IR Drop, electrothermal, and AC impedance for early detection of design issues. In this article, Heidi Barnes, Steve Sandler, and Benjamin Dannan examine why the ability to optimize a PDN for Z_Target with PCB parasitics in the frequency domain and then export to an end-to-end PI Digital Twin simulation for validation in the time domain should be standard practice for the PI engineer.

In this article, Steve Sandler presents several methods of measuring battery impedance, discussing the reasons for conducting such measurements and the challenges one might encounter along the way.

Awarded the Best Paper Award at DesignCon 2024, this paper demonstrates that, for correlated data with PDN impedances in the sub-mΩ level, the impedance extracted from same-location top-bottom measurement can be significantly different from same-side adjacent via pair measurement, even if the physical separation is in the order of a mm