Issue link: https://iconnect007.uberflip.com/i/1126810
28 DESIGN007 MAGAZINE I JUNE 2019 Design for the Unknown Feature by Kelly Dack, CID+ Our industry loves DFX, also known as the "Design Fors." As PCB designers, we not only design for manufacturability (DFM) but we de- sign for assembly, reliability, cost, test, and many more factors which we like to lump to- gether as DFX. But now, I think it's time we embrace a new DFX: Design for the Unknown, or DFU. I'm a firm believer that electronics develop- ment really does start with the PCB designer. I am a big fan of Stephen Covey's The 7 Hab- its of Highly Effective People. I especially like to practice habit No. 2 when beginning a new PCB project: Start with the end in mind. All too often, project teams seem to push ahead with only what is known about a project at the time, even to the point of starting the PCB lay- out. Proceeding on risk is a strategy that proj- ect teams use to make progress on a project de- spite not having all of the data or constraints. But proceeding on risk may have only a small chance of working out. When incor- rect assumptions are made about a product, great amounts of resources will most certain- ly be wasted. Years ago as a salaried PCB designer, I'd eagerly pushed ahead on de- sign layouts overnight, on risk, only to be informed by a program manager the next morning that an assumed board outline or component needed to change. This affected the entire layout! Assumed risk in these cas - es obliterated hundreds of healthy sleeping hours of my life that I'll never get back. I needed a new strategy. Thereafter, besides committing to design PCBs on an hourly basis, I sought to discipline myself to get all of the blanks filled before start- ing a PCB layout. I would do better at starting a PCB layout with the end in mind because "the end" is the culmination and validation of so many critical details which the design started with in the first place.