Issue link: https://iconnect007.uberflip.com/i/1533085
MARCH 2025 I DESIGN007 MAGAZINE 53 ese will fail inspection and require rework, or worse, fail in the field. A simple controlled heat path provided with the thermal relief pat- tern could have saved the batch. Unclear or missing documentation can bot- tleneck an entire project. If you send incom- plete design files or forget crit- ical details, like drill files or stackup diagrams, your man- ufacturer must reach out to the designer for the pertinent information. I recall a project where the documentation was so vague we had to call the designer three times to con- firm basic details. By the time we had what we needed, we'd missed deadlines. The Cost of Getting It Wrong When you don't fix prob- lems early, you pay for them— literally. Every defective board adds to your costs, be it scrapped mate- rial, rework time, or delayed shipments. Hid- den costs can also damage relationships with your manufacturers or end customers. ey are more likely to miss deadlines if they are constantly working to resolve design issues. I've seen companies lose valuable production partners because others deemed them diffi- cult to work with. One designer told me they didn't think a 5% defect rate was a big deal until they realized they were manufacturing 10,000 boards per run. at's 500 boards that needed rework or scrapping. It doesn't take a genius to see how quickly that eats into your bottom line. Fixing the Problem e good news is these problems are pre- ventable. Involve your manufacturer early. Don't wait until you've finalized the design to ask if it's manufacturable. Manufacturers know their limits and can help you adjust your design before it's too late. Make sure your design rules match the man- ufacturer's capabilities. If they say their mini- mum trace width is 4 mils, don't design with 3-mil traces and hope for the best. Use auto- mated DFM tools to catch issues like spacing errors or copper imbalances before you submit your design. Finally, communicate. Clear documentation, detailed stackup diagrams, and frequent check- ins with your manufacturer can prevent most bottlenecks. You'd be surprised how many prob- lems disappear when everyone is on the same page. Final Thoughts: Stop Making Your Manufacturer Sweat Designing for yield isn't just about getting boards out the door; it's about getting them out efficiently. Small design tweaks, like properly sized vias and bal- anced copper layers, can make the difference between smooth production and endless head- aches. By taking the time to avoid common bottlenecks like potential layer misalignment or unclear documentation, you don't just help yourself; you help your manufacturer, your deadlines, and your budget. e next time you're about to hit "send" on that design package, pause. Double-check the details. Call your manufacturer if you're unsure about something. Your production line, boss, and future self will thank you. DESIGN007 Matt Stevenson is vice president and general manager of ASC Sunstone Circuits. To read past columns, click here. Read Matt's book, The Printed Circuit Designer's Guide to … Designing for Reality, and listen to his podcast series here.