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Assemblers Play the ‘Revise or Wait’ Game With Designers
June 22, 2022 | Nolan Johnson, I-Connect007Estimated reading time: 2 minutes
Nolan Johnson recently spoke with Duane Benson at Milwaukee Electronics and Screaming Circuits. Duane was pointing out a trend in moving designs into production, which he termed “revise or wait.” This excerpt provides a preview of our exploration of similar topics involving supply chain issues, lead times, and proceeding forward despite the supply challenges.
Nolan Johnson: Duane, the idea of “revise or wait” is interesting. Tell me more.
Duane Benson: It really is. I keep going back to the old “build or buy” idea. See, there are people who say, “I can design that little module much better than someone else can.” But there are also submodules which nobody designs; almost nobody designs their own Bluetooth or Wi-Fi section of their circuit, for example. Instead, you buy a module. You have that decision, though: Are you going to build it, or are you going to buy it?
The “revise or wait” design methodology is very similar except, instead of gambling against your ability to design something better, you’re gambling against the supply chain. We’ve got vendors who are saying some components are out 52 weeks, and then they’re telling us they will be late even to that wait time. We can’t even ask about expedite fees until after those 52 weeks are over. So, what do you do?
Well, perhaps you’ve designed in one of these awesome new little power components that cut the size of your power supply in half; you don’t want to give that up. But is it worth it to wait an extra year before your design makes it to market? Sometimes the redesign will propagate off the board, throughout the system and all the way out to the packaging, but you must make that decision because a significant edge over your competition might be in the balance.
The fun part, of course, comes when the part manufacturer quotes you 52+ weeks, and you go ahead and spend a month redesigning a tiny little bit of the circuit, lay it out again, and get a couple of prototypes made—only to have the original manufacturer surprise you by saying, “Oh, by the way, we happened to get some fab capacity early. So, all those parts that we said you’d never ever be able to get? Here’s a bunch of them.”
That is absolutely the world we live in. Doesn’t matter if we like it or not, that’s where we are right now, and we must be willing to make those kinds of decisions. But trade-offs really are a big part of the stock-in-trade of the engineering world. "Revise or wait" is just another name for what we always do—create great things out of chaos.
I-Connect007 continues to cover industry topics and challenges. Subscribe to SMT007 Magazine, PCB007 Magazine and DESIGN007 Magazine to keep up with the industry conversations.
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