Issue link: https://iconnect007.uberflip.com/i/1284035
70 SMT007 MAGAZINE I SEPTEMBER 2020 Warren: Test points are a big one. Ask early because putting test points in after the fact is a nightmare and can really mess things up. Kolar: Another can be thinking about whether, ideally, all the through-hole parts to be sol- dered can be soldered in from one side instead of both. Looking at, as they can go through SMT and reflow, minimizing the number of passes they have to do. You may not always have that option, but trying to minimize the number of processing steps can be a big one. Warren: From a designer's point of view, for any new designer out there who doesn't have as much experience, IPC is a good starting point. Use IPC as a guide. I can't say that enough. It's not a hard written rule; it's a guide. When you use it as such, it can get you off to a decent start. My biggest complaint is that the stan- dards are huge. You really need to go through them and make a cheat sheet. We took the IPC placement guide information and condensed it down to a fraction of its original size. For anything that doesn't fit within the IPC guide- lines, you can work with your customer and work with the assembler. If you do that, for the majority of the time, you're going to have a pretty producible board with a minimum amount of problems. Shaughnessy: I hear fab and assembly people say designers get all the crazy signal integrity stuff right, but they'll put connectors too close to something on the board, and you can't get the cables in. It's the simple mechanical stuff that gets them. Kolar: In fairness, the designers these days, depending on who you're working with, may be working on a project for a big company where they have dedicated mechanical engi- neers, and they have dedicated people provid- ing that info. For a lot of other cases, you're pulling teeth to get the mechanical require- ments. You don't know how the cables are trying to connect there. The customer's say- ing to just do it. For a lot of designers espe- cially, people that are one- or two-person shops, or if they're working with smaller cus- tomers, getting the mechanical stuff right is really hard. Shaughnessy: Do you think the average designer out there communicates with their assembly provider? Kolar: I doubt it. I would expect that most just create the package, I doubt that many commu- nicate in advance. Unless they're handling fab or assembly themselves, then they're creating The team at Monsoon Solutions. (Source: msoon.com)