The Key to Eliminating Bad Design Data: Constant Vigilance

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The I-Connect007 editorial team recently met with Jen Kolar and Mark Thompson of Monsoon Solutions to discuss ways to eliminate bad data from the design process, whether that be from CAD libraries, parts vendors, chip makers, or customers themselves. They key in on some problems and obstacles that allow incorrect data into the design cycle, and then highlight possible solutions.

Barry Matties: There are just so many places where you can introduce bad data into the design cycle. And as you both know, one of the biggest challenges is to get the data that you really need to be accurate right from the start. And, if it’s wrong at the beginning, it’s wrong all the way through.

Jen Kolar: It’s like any additive process, where the errors are added along the way. You have garbage in, garbage out in each step along the way. Maybe you have a thoughtful front-end designer who does a thoughtful design and gives really good input, but you have a PCB designer who’s sloppy and leaves half the detail out of the fab notes. Maybe it was good data into them, but they didn’t translate all that to the fab shop. Or maybe they had good data from one point, but you have those additive errors. Maybe there was a partial error at the beginning, but it just builds and builds, and gets worse and worse.

Matties: The thing is, if it’s good at one point, you have so many different points where it can go off the rails. It could be a combination of good data here, bad data there.

Kolar: I couldn’t agree more, and I think part of it is dependent on who’s driving the schedule in a project; a lot of times, the people driving the schedule just care that it’s started. You have management saying “Start,” so whoever is designing the project is saying, “Okay. I’m still figuring out my electrical design, but I’ve been told to put it in schematic.” You can end up with a project that takes a lot longer, costs more, and works poorer than if you’d just waited and started two months later.

Matties: And you’ll probably be doing multiple re-spins on it as well.

Kolar: Exactly. There are a lot of different sources of poor data: There’s just lack of knowledge, schedule pressure, sloppiness, and there is misinformation. There have been a number of times that we have engineers send us reference designs and say, “Just do what the reference design says.” Then we get to argue that the reference designs have nothing to do with manufacturability, and you repeat that cycle over and over. From our perspective, when you’re getting input data, ideally, you’re getting enough variants of it that you have something to validate against. Maybe I get a board file that has some of the parts loaded. Then, maybe I also have a STEP file or mechanical data that I can sanity-check against that, or the schematic, which is also going to have some callouts.

To read this entire interview, which appeared in the March 2021 issue of Design007 Magazine, click here.



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