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Here’s a roundup of some of the things taking place at DesignCon 2020.

Watch out for those operating frequencies. Here are some tips to avoid EMC emission test failures.

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.

Current density can be an interesting concept. Graphics based on current density can be fascinating. But from a practical standpoint, current density is irrelevant. It is a consequence of other things, not a determinant of them. What follows will explain why.

Poor control loop stability results in degraded power supply rejection ratio, transient response, output noise, and, for mixed signal circuits, degraded jitter. Datasheet application examples and reference designs do not often include stability information, and measurements often conclude the stability is poor.

Here’s what you need to do to enter to win copies of 9 books to round out your SI/PI library—one is out of print and one is hot off the press.

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.

Here are some tips to prepare for a standards audit and avoid being assessed a deficiency.

Measuring small resistance values is not trivial, but since 1861, when Lord Kelvin invented the Kelvin bridge,¹ we at least have a solution for measuring very low DC resistances: the four-wire Kelvin connection (see Figure 1). We measure the resistance by sending a known current through the resistor and measure the voltage drop using separate wires.

Over the years, I have presented to and worked with thousands of engineers, from very young to very old. Many of the problems they bring to me have a small set of common answers. I’ve collected these into 20 basic rules of engineering.