Articles Tagged with ''PCB''

We want to follow this mantra of 85 ohms for PCIe, but it may not be so easy. Here’s a look at exactly what the spec says, and what we can do about it.

With more than three times more webinars offered in our Covid-19 era, we have more opportunities to accelerate up the learning curve or waste a lot of time. I sacrificed hours of my time watching dozens of webinars to identify these three princes. Check them out. They are well worth your time.

Uniform transmission lines are best suited for high-speed data transmission because of their broadband impedance characteristics. In some applications, a minor deviation from uniformity can help in optimizing other desired signal integrity metrics. This paper addresses some of the challenges involved with this approach.

Can common via structures transfer any data rate or are they limited with a defined bandwidth? If so, what limits its bandwidth? And what can be done when the bandwidth of the signal is greater than the bandwidth of the G-S-S-G structure? This technical feature from Dror Haviv explains.

Engineers who design and model power distribution networks require accurate component level models from high frequency down to DC.  Accurate modelling of power connectors can guarantee best power transfer and minimize power-induced noise.  In this paper, which won a DesignCon 2020 Best Paper Award, the authors analyze the frequency-dependent resistance and inductance of various power connectors as well as pin patterns.

Many designs today include three different value decoupling capacitors, or when using just one capacitor, a small value like 0.1 uF. These recommendations are based on 50-year-old assumptions that do not apply today. It is time to reconsider these out of date, legacy design guidelines.

Return current for a signal always finds a way to flow as close to the signal as possible, thus minimizing the magnetic energy stored in the loop defined by the signal and its return path. So, the return current path is the combination of conduction paths that together minimize the stored magnetic energy. Some elements of the return current path may be part of the design and other elements may be unintentional.

Measured S-parameters and cross-sections of PCB interconnects are used in this paper to identify the parameters of electrical models suitable for statistical analysis of interconnects with manufacturing variations. The constructed models reproduce observed effects of geometry and material properties variations on the loss, delay, and impedance, and they are suitable for yield analysis of interconnects with up to 56 Gbps signals.

What are the greatest technical challenges facing connector designs for future high-speed deployments?Jairo Guerrero of Molex delves into the technical challenges for today’s connectors, the influence of applications such as automotive and data/telecom, and he gives an intriguing glimpse into the product development process at Molex.

The ability to analyze and predict the current/temperature effects of isolated traces is helpful, but the actual temperature of a trace may be different because of uncertainties in the actual trace thickness or board material thermal conductivity coefficient. This article traces the effort to see what PCB board parameters have the most impact in determining trace temperatures, followed by a look at related PCB design considerations. Read on to learn more.