Issue link: https://iconnect007.uberflip.com/i/1406534
SEPTEMBER 2021 I SMT007 MAGAZINE 53 ponent vendors have better automat- ed tools, but if we've got manufacturer and manufacturer's part number, it's much, much easier for us just to work that way. We can program our ma- chines with just that much informa- tion. e alternates, you want them on the same line as the primary, except off to the right. at's something that would be helpful, but that's not really standard. Sometimes people put them one above each other in the spread- sheet, and then we must sort through and pick the information out. But put- ting them to the right, that's a stan- dard we would like to see. And make sure you put in every single character in that part number. e prefixes and suffixes mean something. Sometimes it just means the difference be- tween a reel and a tube, but sometimes it's the ISR or the ESR, temperature range, you nev- er know. So put every single character there. LEDs are infamous for having one character in a suffix indicating something unique, like a re- versed polarity—the polarity markings on the diode point to the cathode; a different suffix, the markings on the diode point to the anode. It's the same part, but they went through the marking machine backward or something. Red to green LEDs are famous for that, but I've seen it on green to green or red to red LEDs, especially in the 0402s. I think the manufac- turers of the LEDs sometimes put the parts in the reel backward or something for the polar- ity mark printing. Every single character is sig- nificant. Johnson: ey just turned a bug into a feature? Benson: Exactly. And sometimes the only dif- ference is a single character in that part num- ber. Johnson: Is there something that the CAD tool vendors can do? Benson: Yes. Move forward. Continue to move forward on the intelligent CAD data. I think that's where we could benefit from bet- ter bill of materials management. Some of the CAD tools do a really nice job of bill of mate- rials management, some not so much. ere are different standards in the intelligent CAD data, but most of our customer engineers are still using spreadsheets. And to me, that means there's improvement to be had in CAD tool bill of materials management. Work on that and work on making sure your footprints are right, have ways of validating that, making sure your data has rotation, and more in it. Manufactur- ing is really complicated. e clearer the pic- ture that we get from the data provided, the easier it is for everybody involved and the less error-prone the system will be. Johnson: Some good food for thought, and in- sight, Duane. Benson: I think so too. I appreciate the oppor- tunity to talk with you. SMT007 Duane Benson is director of marketing for Milkwaukee Electronics, Screaming Circuits and San Diego PCB Design. He is also an I-Connect007 columnist. To read past columns or contact Benson, click here. Parts loaded into pick-and-place carts.