Issue link: https://iconnect007.uberflip.com/i/1470111
JUNE 2022 I DESIGN007 MAGAZINE 17 same sheet of music from the earliest stages of the design cycle. e designer will know which fab and assembly providers are best for this job, and the manufacturers will be aware of design intent, because they'll be involved in optimizing the design, and everyone is using ODB++ or IPC-2581. I don't think this happens very oen. Korf: I think it's simple. e designer should have rules that they need to follow to build the board when they start the layout, period. How do we get there? If they had all the rules, it would automatically be designed in the CAD tool. In CAD systems right now, we see legend on pad all the time. I keep asking the CAD vendors, "Why? Don't you folks see that there's legend on pad? Why can't you just delete it automatically? Why do you let it go through?" Also, mask on pad, why do you let it hap- pen? It's your design. Why would we have to fix it and get penalized when we don't catch it? e CAD tools, if they had the rules then they could automate some of these checks and balances. e defect may not ever make it on the board. It's really pretty simple. How to get there is the hard part. I was doing a presentation at an IPC DFX meeting a couple weeks ago, and I said, "What does DFX mean to you guys, in this crowd?" We talked about it for a while. I said, "Well, for me, what's missing in IPC specifications? Most designs use them as a reference. e docu- ments don't give people enough design rules." I've put together a document I'm willing to give to the industry to put into DFX guide and say, "Here are some rules that are pretty common throughout the world." I put these together over the years. I'm willing to give it to them to help us get improved DFX. e indus- try needs to help designers avoid creating bad board datasets because they don't have all the rules. Feinberg: at's a good point. Have you brought up design rules to the IPC? Korf: I just brought it up at our last DFX com- mittee meeting. I think it has some attraction to people. Also, we need to improve specifica- tions, you can't build just per IPC specifica- tions. One example in one IPC specification: there are 40+ AABUS's, in other words, as agreed between you and the customer. at's not a specification. It's a design/producibility