Issue link: https://iconnect007.uberflip.com/i/1276973
AUGUST 2020 I DESIGN007 MAGAZINE 53 Matties: How much time do you think you save by doing it right the first time? Kolar: Pretty much any time you get a question, depending on the fab shop—and especially if you're dealing with an offshore shop—you've just lost 24 hours. When you look at clock time, or if you're doing a really fast build— such as if you're doing a 24-hour or 48-hour build—every second counts on those builds. Some iteration on fab note packages can cost multiple days. We have an internal design review process. One of the areas that we have people really emphasize and focus on is the drawings, going through the fab and assembly drawings. They have a whole checklist they need to go through. That typically can take 30 minutes to one hour for a board. We decided it was worth the overhead time that we have a peer review for every project. Matties: How is it that you understand so much about the manufacturer that you're contract- ing with or sending the job to? Kolar: This is one of the things that we have an advantage in. Half of our people are our PMs who are technical and focus on manufactur- ing. We have about 10 different fab vendors that we work with, so we know what their capabilities are. When we send quotes out, we don't just throw them over the wall. We know by the time we send a quote out who we want to go to, and whether it's based on technology, time, or price point. Sometimes, we'll quote a couple, but usually, most of our vendors know that if they're getting a quote request from us, they're going to get the project if we get it. That allows us to also iterate with them, and that means we know the technology of our vendors really well. We know, for this particular vendor, you're doing a rigid-flex. You need to make sure there's this much pullback between the sepa- ration of these layers. Or we know this other vendor might get confused about something, so, "Let's make sure we call it out specifically." We try to educate our PMs on what to watch for that they might need to call out to a vendor as unusual; this is more of an issue if we don't do the design internally. For example, maybe this is referencing a stackup outside of the fab drawings. We try to have it explicitly called out to help the fab vendor. Matties: We hear a lot about DFM and design for automated assembly. How does all that play into your process there? Kolar: We use CAM350 as a pre-DFM tool inter- nally. We have some streams based on different technology levels, and they are an automated way to do different rule checks on boards. We have some based on low-tech, medium-tech, and high-tech. We've started looking to do some in specific shops. After we've done all of our layout checks, we also required design- ers to do a number of CAM350 checks that look for things that might be issues. Designers might send an internal email to the team, ask- ing, "Remind me of how much pullback I need here, or what clearance do I need here?" There's a lot where we just use best prac- tices, based on experience. This is where Dan ends up being a huge resource for a lot of peo- ple. Our team members are a resource for each other. Following best practices resolves 99% of the issues. If we go outside of best practices, that's when we ask in advance, "Can you han- dle this aspect ratio? We're going to want to do something funky." Matties: Oftentimes, we hear that designers design in a vacuum, not knowing who the fabricator will be. It sounds like you know in advance who you're going to use for particular jobs. That's a huge advantage. Kolar: We do. If we're doing the manufacturing, our designers will know, and they'll work with the project manager to get a stackup specified. We'll know up front who the shop is and what the capabilities are. The PMs are savvy enough to know, and the designers are savvy enough to say, "I'm going to do something kind of funky. Why don't you go check with the shop to see if they could support this?" Where does