Printed Circuit Design & Fab Online Magazine

Roughly Speaking

PCEA chapter meetings can be a great source of education and collaboration.

I am excited that my local PCEA chapter has gotten some traction and we are having regular meetings! After a couple years of false starts and hiccups, the Oregon/Pacific Northwest chapter got the spark and the ball rolling with members coming to connect and learn from each other. Which is exciting! I was able to reconnect with someone with whom I worked almost 20 years ago. He was attending from another country, but still views Portland as his "home area."

As our meeting progressed, we had a good educational segment and then an active discussion about topics to discuss next time. A question came up about a mechanical exchange format, and we just happened to have someone in the meeting who works for the company that manages that format! And if we didn't, I am sure we could have reached out to our separate networks of contacts to find an expert to talk with us about it. Meanwhile, additional topics of interest were shared, along with requests for recommendations on specific types of quality fabricators and assemblers. So add that to our list of people to invite and reach out to.

Read more: Pivoting to PCB Design

A tech conference presentation spurs study of an exciting material option.

I like to ask designers about interesting projects or technologies they have worked on, and I heard from two designers, whom I met through my local PCEA chapter, about some very interesting and complex boards they designed using sintered copper. Both had used sintered Ormet Transient Liquid Phase Sintering Paste (TLPS) to design boards that would not have been possible otherwise. (There are a couple different vendors for sintered copper for vias, but I looked further into Ormet materials, as that was the material used in both the boards they told me about.) These boards were complex, with a lot of parts, limited space, RF signals with antennas and sensitive digital components, and I was told these boards would have been impossible to design without the sintered copper to create any-layer vias connections.

The Ormet paste provided a path forward to route, but this wasn't the first time I encountered this material. I first heard about it in 2014 from a fabricator that wanted to be able to document these types of vias in their stackup. In the past two years, however, I heard more and more requests for it from both designers and fabricators. What is it, and why has it taken so long to get traction in the PCB industry? This prompted me to put on my investigation cap and pursue some answers.

Read more: Sintered Copper Can Handle the Pressure

Models can reveal what design rules "forgot."

A picture is worth a thousand words, and that is especially true when evaluating the impact of changing trace dimensions in your printed circuit board.

The capabilities today of visualizing, in a matter of seconds, the complexity of the electromagnetic fields in one's printed circuit board are astounding. Twenty years ago, software tools to help designers make informed decisions were limited to numerical outputs or very rudimentary images. Often one required a significant level of understanding of the physics involved as well as a solid imagination to properly visualize the electromagnetic field lines and their significance. Even then, most visualizations were representations, not actually calculated fields displayed over the actual board and components. Many tools today provide unprecedented insights through such visualizations, equipping and enabling quick and intelligent decision making by designers on an unprecedented level.

I recall – and I hope you had a similar experience – a science class that used iron shavings and a magnet to make visible the once invisible magnetic fields as in FIGURE 1.

Read more: Changing PCB Trace Dimensions