Issue link: https://iconnect007.uberflip.com/i/1315894
34 DESIGN007 MAGAZINE I DECEMBER 2020 tion comes up, send an email or walk down the hallway and ask manufacturing. I can't expect you to be a manufactur- ing expert." One of the big problems is that there's never been a detailed diagram of how a PCB is designed. At some point, you have critical questions about placement, layout, and all these different things that can go wrong. We would then take these questions over to the CAM people and say, "Provide an answer for these things and normalize it in terms of the cost of the final PCB." These dif- ferent choices had costs associated with which ones were cheaper than other ones. Then, we'll write that and put it into a table or a check sheet for designers. If they hit that point, they could at least get some indication of the ramifications of the choices they have to make. I've never seen that in any book, design course, or IPC standard. If there's an infinite number of ways of laying out a PCB, how do you choose the optimal path? What if I placed this CPU close to the edge where I could only route out at three sides instead of four sides? Ford: The outlook is a positive one, as there have been some interesting recent developments. A couple of specific things have happened. First of all, revision C of the IPC-2581 standard, now called DPMX, is imminently about to be pub- lished. Revision C has a new module within it, specifically for DFM feedback. Now, this is not the old-style, rules-based DFM, which is basically a design rule check with just a few more rules that have been introduced from a manufacturing perspective; it is a mechanism through which designers and manufacturers can directly communicate in a defined, digital way. Instead of sending a multitude of docu- ments and drawings, having phone calls, and exchanging emails—all of which can easily get lost or be misinterpreted—there is one channel through which all of the information flows. The second interesting thing to happen is that the DPMX file (i.e., IPC- 2581) is now starting to be used in assembly manufactur- ing itself. Previously, design data would flow primarily into a digital manufacturing engi- neering system, which would calculate all of the different pieces of data required for each of the machines, as well as applying the local BOM. When it came to machine program- ming, however, the machines would need more information about the design of the prod- uct. To address this, the IPC Connected Factory Exchange (CFX) IIoT data exchange features the ability to send the original IPC-2581 file to the machine directly so that the whole of the design data can be immediately and accu- rately referenced. We're going to see a couple of press releases in the very near future where the most advanced machine vendors are actu- ally already adopting this. Holden: That's kind of like a TAM network. Ford: Yes. The problem has always been that the design information itself has been difficult for the different domains to fully understand. The IPC Digital Twin, as has recently been defined, architects how information should be made available across disparate domains. Informa- tion from different processes is resolved down to the digitally understandable content, such as what you get from a DPMX file. This is now one part of the overall digital twin. It's the con- nection and interoperability that the design and manufacturing world needs. Nolan Johnson: Does this start to set up the opportunity for CAD tools and fabricators to talk more real-time or interactively as the design progresses? Ford: It's the first stage. What we would like to see with the designer is instead of being project-based with a cut-off before the prod- uct is introduced into manufacturing, they Michael Ford