Issue link: https://iconnect007.uberflip.com/i/1478618
12 DESIGN007 MAGAZINE I SEPTEMBER 2022 product to production. At that point, we evalu- ate the product to determine its feasibility for meeting the capabilities of our assembly lines. Everything is fine, just like it always is—until it's not. at's because with today's rusty, knot- ted supply chain we are not able to source cer- tain components. at one little thing can slow down or stop the entire project. We limp along until we can either change the design, modify it so that we can find an alternative component, or redesign the circuit so that we can use alter- nate components that will do the same thing. Happy Holden: You understand design for man- ufacturing. Now we're not talking about pro- cess capability; we're talking about part avail- ability, but that's still manufacturing. Dack: at is still manufacturing and sourcing, and that plays into it, Happy. A product can be totally 100% designed and look very good from a production standpoint and from a DFM standpoint. But now, when a part suddenly becomes unavailable, it could require another part to be designed in, which may not be form- fit and functionally the same, but it could still work. But now designing in this part has to be done properly so that design for manufactur- ability is considered. How many parts do you have to nudge? What's the domino effect if we do manage to fit this part in? Holden: So, we have to make a change in design so that the information is known up front and it's not a do-over? Dack: e problem we're finding is that every- body is using the smaller parts, and the large parts are le over. So, if you want to find an equivalent functional part, chances are all the tiny ones have all been gobbled up, and you must be willing to buy the larger-scale parts. But how do you fit the larger scale parts into your layout? Shaughnessy: ere are those dominoes, right? Dack: Right. Let's take a step back. During the shrinkage era in the '90s, when we were work- ing on iterating boards down as small as they could be, I coined the term "practical pack- aging density plus." e idea is that we deter- mine an appropriate packaging density, and then once you get that dialed in, what's wrong with adding just a little more for future design purposes or manufacturing purposes? Why do we constantly design to the minimum, tightest density? Shaughnessy: Are you talking about adding more real estate? Dack: It can be real estate. Packaging density has to do with the amount of real estate on a given PCB vs. the components and everything else, and all the geometries involved with the components. Barry Matties: But you're bound by the enclo- sure that it's going to live in. You have those constraints on you. How do you adapt to that? Kelly Dack