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Randy Faucette is founder, president and director of engineering at Better Boards Inc. in Cary, North Carolina. Founded in 2003, Better Boards provides electrical engineering, PCB design, signal and power integrity analysis, and a variety of other services. I asked Randy to talk about some of the occasional tension between PCB designers and design engineers, and what he thinks can be done to help open the lines of communication.
Andy Shaughnessy: Randy, tell us a little bit about your company and how you operate.
Randy Faucette: Better Boards is a PCB design and engineering services company. We specialize in all aspects of PCB design, but also provide electrical and mechanical engineering, software/firmware development, prototype and small-volume production manufacturing, and many types of analysis including failure mode, root cause, thermal, crosstalk and power integrity. We use a breadth of design tools including Cadence Allegro, Altium, Mentor Expedition and PADS. Our customers range from large companies like Lenovo and Cree to small entrepreneurs. We perform finite services our customers define to full development of products from concept to production. We cover many industries, such as medical, commercial, consumer, telco, and space/military.
Shaughnessy: A recent survey of our PCB designer readers found that there’s often friction between PCB designers and engineers. Some designers say, only half-jokingly, that their EEs are their biggest challenge. Why do you think there’s such disconnect at some companies?
Faucette: We have not found that to be true here at Better Boards. We approach PCB design from an engineering standpoint. The PCB designer should not just be a tools jockey hoping that engineering will tell them where to put parts and how to hook them up. The PCB designer should understand how the circuits flow, understand the different types of interfaces and how those need to be treated on the board, and understand the manufacturing aspects as well (including test). The only challenge we experience with engineering honestly is playing the role of middleman between engineering and manufacturing. Engineering may want parts located too close to another component or too close to a through-hole pin, not allowing a proper wave soldering operation to be performed. Those drive costs and can affect reliability. If the layout designer is effective, engineering is happy and manufacturing is also happy. That makes the boss happy!
Shaughnessy: What do you think is the proper role for a PCB design engineer?
Faucette: Outside of creating a correct schematic, the PCB design engineer needs to effectively communicate ALL of the requirements of the board and then review the board once designed to ensure all the requirements have been achieved. Some examples of requirements would be interface impedances, timing rules, and power requirements. It’s also important to identify high-speed nets, clock lines, sensitive nets/circuits, high-current buses, thermally hot nodes, high switching loops. The stackup is critical in most designs today and this must be considered early. One thing that should be communicated early on is the environment of the product and the expected reliability. The temperature and humidity can drive what component packages to use (or more importantly what not to use). The reliability can drive board technology and spacings. The best way to communicate all the rules is in a PCB requirements document. This is the scope of the layout. If it’s in the document, it’s important. It also removes the flurry of comments, instructions, and “Oh, BTWs” that tend to arrive in various emails and in cubicle conversations. It’s a captive, living document to keep everyone straight. It’s also it a perfect checklist at review time.
To read this entire article, which appeared in the April 2016 issue of The PCB Design Magazine, click here.