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Design and Manufacturing Perspectives from DISH Technology’s Les Beller
May 30, 2018 | Barry Matties, I-Connect007Estimated reading time: 23 minutes
Beller: I don't have a lot of access to a lot of different design tools these days. We use Mentor and share databases when needed. Now that takes patience! Probably the more management-pleasing feature we use is multiple designers within one database. We still find a high value to that, cordoning off the board and allowing the designers to work in their respective areas. That gets our designs out into the market faster. However, it seems like these days we still don't have a good internal inclusive DFM type of tool without buying the third-party solution or the extremely expensive solution. Valor is a good tool for a high-volume design department, but give me a tool where you don't have to pay an excessive amount of money for DFM, and that's going to be the tool for me. In our organization, we decided not to purchase Valor because having a person trained just to run Valor and the maintenance costs of Valor are high; it’s a high cost of entry for low design volume. We still do manual checks using checklists. We have experienced people who go over the designs during the design cycle and when they’re completed, but occasionally we can still miss something. It’s manual, but it mostly works.
Matties: Is that decision based on the volume of work that you're putting through, or on some other factor?
Beller: It's based on two factors: not spending money where we feel like we don't need it, and the fact that we don't have an excessive quantity of boards that we're designing like a service bureau would. A service bureau or a very large company that's doing 20-30 designs a month can benefit from the Valor tool and could justify the cost.
Matties: You have to weigh your specific need there. But at the end, you must do some sort of DFM.
Beller: Oh, absolutely. We've learned through the manufacturing world of hard knocks with a lot of different suppliers that the CM’s DFM rule list is not always perfect either. We've given them our designs, have them run it through their Valor checks, and we've gone through and looked at it. We found that a lot of them are canned responses, and through building the boards after that, we found many more issues that should've been caught that were not. Your DFM checker is only as good as the person who inputs the variables that it looks for.
Matties: The other topic that comes up is best practices. As Happy Holden says, “There should be a red light, a green light, and an orange light right on the tool.” Best practice, green. You're doing great. And the red is “What the hell are you doing?” But there aren’t a lot of tools like that.
Beller: Yes, like an online check for everything during the process.
Matties: I guess best practice is still subjective.
Beller: Yes, it is. It does depend on your market target as well. If you're doing a lot of low-speed consumer-grade type products, high-volume low-mix type products, you can shove them out the door and just put another person on the end of the production line to deal with your design issues. If the design issue is significant however, this can add labor cost. If you're doing high-spec work, then you need to hit the target right off as rework may not be an option. Right now, with most design schedules, you can't afford six or eight revisions of your PCB to get to market. You need to have it right in two versions. We typically had 6-8 versions of boards getting to MP volumes, but now have this at 2-3 versions.
Matties: That's the other case that Happy makes is we need predictive engineering. We need to be able to predict before we even design. Even with the DFM check, it's a spin and re-spin process in some cases.
Beller: For example, one of our international CMs has a design guideline, and it's a matrix—resistor to resistor, resistor to capacitor, IC to resistor—basic component spacing requirements. They'll have the minimum, the nominal, and the preferred. Well, of course their preferred is that they want a tenth of an inch from every component to every other component for “repair.” That's not reasonable except around some larger parts that might need rework (CPU/Flash, etc.), and it’s not even realistic. Some of those numbers were practical 20 years ago, but not now. We push the bottom end and every time, the CM that runs Valor gives us back a DFM listing that's a mile long. We try to get them to adjust, but it’s hard to do that with a canned/mature rules file.
Matties: What about the thermal issue in what you guys are doing?
Beller: There are two predominant issues in most of our designs. One is thermal and one is signal integrity. Thermal has caused delays in the middle of some compact products and requires that we think even more outside the box than we thought we had. We've had to completely change some very compact products and how they spread the heat away from the processors; some people call them heat spreaders or heat sinks, but most are custom fabrications. As the processors get smaller and more complex, they run hotter. As we ask switchers to do more, they're running hotter. In a small, compact product where you don't have a lot of air movement through the product, you're just going to keep building up heat until the product just gets too hot. Like a lot of cellphones now. Use them for 10 minutes and you feel it. Thermal is one of our big issues within our products.
Matties: How do you deal with that? Are you using predictive engineering?
Beller: We've gotten much better over the last five years on the predictive side. We've installed thermal modeling software. We plug in the envelope sizes and the temperature ranges of all the chips in the product. They've got all the thermal characteristics of the laminates, etc. They plug all that in and we try to see where all the heat problems are going to be. We'll use that to change the case ventilation and add a fan (worst-case scenario) or go with a larger heat spreader to try to dissipate that heat out.
Matties: Along those lines, what about materials? There is a lot of talk about the copper foil market where a lot of the foil was being consumed by the battery market. Standards are lower, so it’s easier for the suppliers to deal with that.
Beller: Let's talk about where we're going with copper. That's an easy one. That's a low-hanging piece of fruit. We have had significant price increases across the board over the last year, month-over-month in some cases, where we've heard the prices are going up again! I'm concerned with the longer term, not just this year or next year. I've understood that there are some changes in the mining industry that are going to cause a shortage of copper, if what I read was correct. It's based on how they're exhausting some mines and bringing other mines online. There could be a lag in the supply chain. That's only going to become more of a crazy issue, especially with China moving more to electric cars. They're already talking about it in California now with new electric car requirements. The procurement people need to stay on top of this as batteries become larger and more common. We're going to hurt ourselves in other areas if we can't come up with a different battery technology. So far, we haven't had any phone calls saying, “We can't get the laminate,” or that the laminate is shipping late. It's just literally on every quarterly business review, the prices will go up maybe 5-7%, quarter over quarter. Right now, it's just a cost issue. Which for us, if you've got a set product price, it will be affected. Luckily, some suppliers we use have better agreements with their laminate fab than others, so we may not see quite the increase.
Matties: Bottom-line dollars.
Beller: We can't keep increasing our product price to our customers.
Matties: It's interesting to think about the satellite market switching, because I don't know how many people are putting satellites or dishes on their houses anymore.Page 3 of 4
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