Carl Schattke on Stackup Design and Managing the Component Shortage

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At AltiumLive, I met Carl Schattke, CID+, a lead PCB designer with an American automaker. Carl and TTM’s Julie Ellis taught a packed class on good stackup practices complete with plenty of slides showing examples of all kinds of stackups. After the class, Carl explained why the stackup is often the root of manufacturing problems downstream, and why today’s discrete component shortages are likely to be around for quite some time.

Andy Shaughnessy: Carl, I saw part of your class with Julie Ellis. It was pretty interesting and entertaining stuff. How did you get the idea to put the class together?

Carl Schattke: We were thinking about different presentations, and Julie thought that it might be useful to co-present on PCB layer stackups because I bring a design perspective and she brings the manufacturer perspective. We decided it would be useful to put a presentation together that would address how to communicate between a designer and the manufacturer, what information to communicate, and why that’s important.

When I was planning the talk, initially, I thought, “Wow, this is a big subject.” There's a lot of different areas to pull in because you have the physics of the board technology, and then you have the communication with your vendor. Then, there are all of the parameters that are involved with PCB layer stackup. It impacts your cost and lead times, and impacts who you can make the board with. As I said in my talk, it's basically how an artist uses a canvas. Our artwork requires a board layer stackup. When we put all of our geometry on there, it starts with the layer stackup, and our paintbrushes are the components and traces we use; that's how we end up with beautiful art work.

It's technical, unlike somebody with an easel, but it's the same kind of thing. We are looking to create artwork that is going to be manufacturable, cost efficient, and effective in providing the electrical connectivity that we are looking for. I wanted to start the presentation with some of the basics, then discuss what could go wrong, so we covered a variety of examples of the kinds of problems people can encounter with their PCBs and their stackup. Next, we covered the physics of PCB layer stackup and how you solve those problems. We talked about some of the areas when communicating to get a certain type of board built. Then, we went in to some of the costs and different problems.

To read this entire article, which appeared in the January 2019 issue of Design007 Magazine, click here.




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