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PCB007-Sept2019

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12 PCB007 MAGAZINE I SEPTEMBER 2019 national standards bodies, publishing specifi- cations developed by industry consensus, and that's one of the problems. If you have a room full of suppliers of a prod- uct, for example, and you say, "Let's write a standard that applies to all of our customers," you end up with the lowest standard that they can all live with and that you can drive a bus through, more or less, in terms of what the real requirement is. An example I was discuss- ing this morning was a standard about FR-4 materials, for example, which says that you have to have a dielectric constant maximum val- ue of 5.2. If you turned up with a product that had a Dk of 5.2, virtu- ally nobody would be able to use it because the requirements have moved on. Typically, you'd want to be look- ing in the low fours or even the threes now; that's the standard. That's the issue that we're faced with be- cause the standards and specifications are gen- erally based on the old NEMA standards, which were developed in the 1950s and 1960s based on things like simple resin chemistry, epoxy resins, phenolic resins, polyimide resins, etc. And they've been extended to cover a whole explosion of new materials. The industry has expanded massively, and we still shoehorn our new products into these old standards based on dated ideas of classifications. What we need is a more performance-based approach now, saying, "I'm a designer and design boards for satellites that go into orbit. These are the kind of things that I need." As a board designer, I'd find it very hard to know how to choose a material based on the standards that are available. And for some ar- eas, such as IMS materials, there aren't any agreed-upon standards either. That's quite nor- mal; standards usually take two to three years to go into print from the first idea. Matties: If this approach is sensible where it's application-specific standards, what's the cata- lyst for change? How's that going to happen? Morgan: It's the designer's requirement. The designer goes to his board shop and says, "I want to build a board to go under the hood of a car; what material shall I use?" They ask the board shop, and that's the problem; they're not accessing all of the materials or options available to them because they don't know, and they have no way of selecting now. Matties: If the designers, as a body, said, "We want to change the methodology and the way that the standards are done with IPC," and the members buy in, do you think it would hap- pen? Morgan: I think it would. IPC does run auto- motive and other specific forums now. Some- body has to recognize that this way of specify- ing standards doesn't work anymore and they have to start again, but that's a huge decision because there's a lot of investment there. There are also a lot of people who have been fight- ing this stance for years, including me, since the 1980s. We've come to a point now where they're not fit for purpose and need to be rei- magined to meet the needs of today's OEMs. Goodwin: To some degree, there is a window of opportunity if we can somehow put this out there to make it happen because there are some disruptive elements in certain sectors now. Au- tomotive is one with the move from internal combustion engines to electrically powered ve- hicles, including the new players that are com- ing in with a less traditional business model, such as Tesla and others lining up to be in that market. The same is also true in commercial aerospace. A lot of those people come from a more modern technology background, not a traditional technology background, and they will take different views. There is a chance there. Where we'll struggle, of course, is places like the military where they never change any- thing because the perceived risk is too big for everyone. Nobody wants to sign off on it. Alun Morgan

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