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As we move into 2020, we took a look back at the most popular Design007 columns of the past year. Here for your enjoyment are the Top 10 most-read Design007 columns of 2019.
1. Lightning Speed Laminates: Practical Evaluations of Glass Weave Effect
There are a few things to consider about glass weave effect. One point of interest is when a laminate is using more than one layer of glass, the glass weave effect is somewhat dampened due to an averaging effect of the glass weave layers with their random alignment to each other.
2. Embedding Components, Part 7—Semiconductor Placement and Termination Methodologies
Progress in developing high-density embedded-component substrate capability has accelerated through the cooperation and joint development programs between many government and industry organizations and technical universities. In addition to these joint development programs, several independent laboratories and package assembly service providers have developed a number of proprietary processes for embedding the uncased semiconductor elements.
3. Flex Time: Alternative Constructions in Rigid-flex Designs
In his previous column, Bob Burns discussed how manufacturers of rigid-flex boards use techniques similar to those used by manufacturers of hard boards and flexible circuits. This column will talk more about non-standard designs, which can present process difficulties and require extra care for effective yields.
4. Beyond Design: 10 Fundamental Rules of High-speed PCB Design, Part 4
Part 4 of the 10 fundamental rules of high-speed PCB design deals with the routing of critical signals and return path discontinuities. Needless to say, matched delay and length, differential pairs, and other critical signals should be routed first with the precision they require before less important low-speed and static signals are completed. Maintaining this priority is imperative.
5. Sensible Design: Conformal Coatings—How to Design Out Production Problems
In my last few columns, I’ve covered quite a bit of ground regarding the important considerations for conformal coating selection and performance. In this column, I’m going to look at the different angles that design engineers and purchasing professionals come from and explore how these can sometimes conflict when selecting conformal coatings.
6. The Pulse: Modelled, Measured, Mindful—Closing the SI Loop
In this woolly world where high-speed signals enter a transmission line with a well-defined shape and emerge at the receiving end eroded and distorted, it is well worth running simulation to look at the various levers that can be figuratively pulled to help the pulse arrive in a reasonable shape. At speeds up to 2 or 3 GHz, it usually suffices to ensure the transmission line impedance matches the driver and receiver.
7. The Bare (Board) Truth: Teaching the Next Generation
In this column, Mark Thompson focuses on the University of Washington, where he counted approximately 163 programs in their catalog of electronics courses. He shares the top 19 courses he thinks are the most valuable for emerging electronic engineers if he were to start his electronics career over again.
8. Beyond Design: High-speed PCB Design Constraints
Digital design has entered a new realm. Modern high-speed design (HSD) not only requires the designer to continuously break new ground on a technical level but also requires the designer to account for significantly more variables associated with higher frequencies, faster transition times, and higher bandwidths.
9. Powerful Prototypes: Seven PCB Cost-reduction Design Tips
Like everything else in the modern world, design decisions can have a pretty big impact on your manufacturing cost. Here's a list of seven design decisions that can make your manufacturing more affordable.
10. The Shaughnessy Report: Reliability is a Team Sport
Reliability has been in the news quite a bit lately, and as always, it’s when something has proven to be unreliable. In 2018, IPC formed the IPC V-TSL-MVIA Weak Interface Microvia Failures Technology Solutions Committee to try to find the root causes of microvia interface failures that have been affecting the defense and aerospace segments. Members of that subcommittee spoke at the IPC High-Reliability Forum and Microvia Summit in Baltimore, Maryland, and I was fortunate enough to cover that conference.