Issue link: https://iconnect007.uberflip.com/i/1007258
14 FLEX007 MAGAZINE I JULY 2018 tain times when you can use flex to, let's say, reduce layer count, or to eliminate connector headers. And if you could incorporate it into the design in such a way that it's serving some other purpose than just connecting board to board, then it makes sense. As an example, we figured out on one of our products that we were just going to use a board-to-board con- nector, but we realized we could actually get rid of an entire six-layer circuit board by put- ting LEDs and microphones right on the flex circuit. It was an elegant way to connect two rigid boards and serve an additional SMT func- tion in that case. That's where I would say it's probably on a one-to-one basis. It may not always be cost- effective, but you have to look at the whole of the design and that's really what I mean when I talk about getting our design team to think about circuit designing a different way. It's not just two-dimensional now. You have three degrees of freedom, which can be thinner and lighter, and how can you leverage those advan - tages? It's been really great. We often get a lot of iterations within a set. We're seeing more design innovations within the development cycles than I think we ever had. It's partly because people think, "Oh, if I could just tweak this a little bit and move it over it would be more efficient." Shaughnessy: That's cool. What kind of back- ground do you have? MacFadden: I studied chemical engineering, and my introduction into the electronics indus- try was doing work on lead-free electronics for my master's degree. At the time that the indus- try was transitioning to lead-free solder, so I started at Bose at that early stage to help make that transition for the company. It was exciting because that, too, was such a transformative event for the industry. It was very exciting to be on the inside, and again, I had to work with people throughout the company from document control to the assembly line and everybody in between about how to make this change. It was a neat w ay to start at Bose. I got to know a lot of people. Oh, and we had to give weekly progress status updates to the execu- tives, so at my first job out of grad school I was talking to the president and the whole executive board on a weekly basis. Another one of the great things about Bose is that the executive- level management are all accessible. They're all engineers. They love creative ideas and talking technical with all the engineers at any level of the company. It makes it really exciting. Shaughnessy: How many PCB designers work at Bose? MacFadden: First, there's never enough, you know? There's a team of designers, and they work really well together, and it's nice that we have different divisions in the company: auto- motive, professional, consumer electronics, and then R&D groups, but those board design- ers work very well cross-divisionally. They share what they've learned. We have common design rules that we all learn from. We're con- stantly updating our design rules these days, because the technology is changing so fast. At least once a week I get a call from a designer who says, "I know in our design rules we're supposed to have a minimum keep-out of X. Can we just push that a little bit tighter?" So we're having these conversations all the time. Again, this is where getting in front of the board suppliers and their technical requirements is really important at the very beginning. Shaughnessy: Fabricators often say, "Take advantage of our knowledge. Let us educate you." As you say, you may not know every- thing about flex. MacFadden: And we don't, and we really have relied on that expertise from the supply base Figure 2: Bose discovered that flex is a much better fit than a rigid board for their latest electronic devices.