Issue link: https://iconnect007.uberflip.com/i/1126810
JUNE 2019 I DESIGN007 MAGAZINE 23 the stack-up and design rules. We can also re- view the technical queries that came up during CAM on the old part and get them corrected on the new part, so we reduce the Q&A time delay on the new fab. Very few of our customers can pay attention to the design rules enough to do their own pan- elization. I have a couple who do, but it would be great if customers were more aware of that. I think everybody gets confused because dif- ferent sites and regions have varying require- ments for the keep-outs required around the fabrication panels for tooling holes, and no- body is sure what width rails an assembler needs on the array to run through production. It's easiest if the PCB designer, fabricator, and assembler work together to get the rules for assembly, and then let the fabricator optimize the array on their production panel. Matties: Right, because this thought up front can help drive cost out in the tail end. Ellis: It does. Recently, I worked on cost-reduc- tion of a North America production part mov- ing to China. By reducing the rail widths on all four sides of the customer-designed array, I was able to increase panel utilization and re- duce the unit cost 7.9%. Matties: And when you're talking about 500,000 parts, that can add up quickly. You said that early collaboration is commonly of- fered as advice. What other advice would you give a designer who is seeking the most successful design and manufacturing experi- ence? Ellis: Talk to your fabricator and assembler and follow the KISS (Keep It Super Simple) princi- ple. From the user's point of view, if something goes wrong and they have to troubleshoot or fix something, a complicated, difficult-to-build design will also be difficult to take apart, repair or rework. Think of your whole system from the outside in, and then start building from the inside out, thinking of the bigger pieces that follow. Matties: I appreciate your time, Julie. Thank you. Ellis: Thank you. Everyone had interesting questions. Shaughnessy: That was fantastic. Thanks a lot. DESIGN007