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52 DESIGN007 MAGAZINE I AUGUST 2020 time to fine-tune and dial in a process that works. Our com- pany is split evenly, as a ser- vice bureau, between design and manufacturing. We have our people all intermixed and working closely together. One thing that gives us an advan- tage is our designers hear first-hand when the program managers (PMs) are getting questions from the fab ven- dors or problems from the assemblers—as well as when builds get delayed—so that they're very aware of the back and forth process. From the manufacturing and requirements side, we worked with quite a few different fab vendors, both in coming up with standard templates for quotes and stackup requests, and then also what works well in our fab notes. From that side, we've helped the design side understand, "Here are the things we get questions on, that might add a day or two to the build, and that might add cost to a build." One of the things about Monsoon is that we do a lot of builds for people that want it yester- day. We optimize to have no delays. Our biggest delays come from poor assembly diagrams that don't match with silkscreen on the boards that are missing reference designators, or polarity markings, and poor fab drawings. Those are the two biggest sources of delays. After that comes, "There was a footprint mismatch." Barry Matties: How much extra time do you have to spend on a job to make it accurate when you send it to the fabricator? Dan Warren: For us, not much, really. It's all part of a larger process. If you don't have a process in place, and you don't have anything documented, you're going to waste a lot of time making sure everything's accurate. If you leave it up to 13 different designers to do it with no process in place, you're going to get 13 differ- ent sets of documents. The fab notes are just a small part of it. We have a series of internal documents that we've written, and one of them handles what goes in our output packages because we have multiple CAD tools, and they're all a little bit dif- ferent. We also have specific cus- tomer requirements. Some of them use our notes, some use their notes, but that's also documented. The designers are expected to know this process and look at it once in a while. We try to imple- ment a continuous improve- ment process where just because you did it and it's done, don't ignore it for three years. About every six months to a year, we'll go through the documents and refresh them. I also have a folder in my inbox. If any designer comes up and says, "This note is out of date," I make a note about how this needs to be updated and we get it done. That saves us a lot of time when it comes to the process. The first time through, you can do a draw- ing quickly. You can get your fab data out, and then if something minor changes and you have to reprocess it, you know it's all golden and ready to go; you can reprocess it in half an hour without having anything automated. We live by the rule that if it's not on the board, it shouldn't be on the drawing, because that just confuses the fab shop. If you have notes about blind and buried vias, but you have a through-hole board, those notes need to come off. In our standard notes templates, we have notes for blind and buried vias and via-in-pad different finishes. Pick the ones you want and get rid of the other ones. Kolar: We have predefined templates for differ- ent drawing sizes and ideas of where we want things to be on the drawings. "Your stackup should appear here. Your drill charts should appear here. We want things to all look and feel the same." Jennifer Kolar

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