Signal Integrity

RSS

Designing the right PCB stackup can make or break product performance. If the product has circuitry that is impedance and transmission loss sensitive, then paying attention to conductor surface roughness is paramount. Sometimes, however, the roughness of adjacent reference plane(s) is overlooked. If the adjacent high-speed signal layer uses smoother copper than one or both reference planes, a higher insertion loss than expected for that layer will occur and possibly cause a product to fail compliance. So, how is this determined before finalizing the stackup? Read on to find out.

It has been a year and a half since we last met in person for DesignCon 2020, and the event organizers are aiming to make the in-person experience of DesignCon 2021 in California compelling and educational. Here’s a look at what to expect.

The continued progression to higher data rates puts increasing demands on the design of practical SerDes channels. At 112G-PAM4, the UI is only 17.86 ps, and signal transmission in the PCB must be highly optimized for loss, reflections, crosstalk, and power integrity. This article summarizes the key elements of a study that describes the signal-integrity and power-integrity design process and shows simulated SI and PI performance correlated to measured data as well as measured eye diagrams of a test board that uses a 112G-capable silicon and high-speed compression-mount cable connectors. 

Fans of a single, multifunction instrument that replaces a dozen benchtop instruments will be excited with the release from Liquid Instruments. Here’s a closer look at this multi-function instrument that combines the features of a bench top full of instruments, like a scope, a DMM, a function generator, a frequency response analyzer, a spectrum analyzer, and even an impedance analyzer, all into one USB controlled instrument. 

Eric Bogatin has a little fun with engineering in this tongue-in-cheek celebration of EE jargon; don’t forget your flux capacitor!

SIJ Technical Editor Eric Bogatin reviews two webinars: one on additively manufactured electronic circuits and one on automotive circuits.

Benjamin Dannan and Steve Sandler teamed up to explore the tradeoffs for various calibration methods and offer some recommendations and considerations to make accurate sub-milliohm impedance measurements.

The conventional PCB fabrication process for printed circuit boards is subtractive. Averatek recently introduced a new chemistry technology making semi additive circuit board fabrication more attractive for ultra fine line applications. SIJ’s technical editor, Eric Bogatin, takes a closer look.

Understanding a few simple power integrity (PI) fundamentals can go a long way towards increasing design margins when delivering power to high-speed digital loads. In this piece, Heidi Barnes provides some fundamental lessons on impedance.