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As a PCB designer working for an EMS provider, Kelly Dack has seen his share of boards fail because they were designed in a vacuum; the designer simply threw the design “over the wall” and hoped for the best.
In this interview, Kelly discusses the need for collaboration between all the stakeholders involved in designing and manufacturing the PCB. As Kelly points out, IPC’s CID curriculum provides a great framework for setting up a collaboration culture in your company, and standards help enable this kind of environment.
Andy Shaughnessy: Kelly, we’re discussing collaboration between designers as well as between designers and their partners downstream. How does a company set up a collaboration culture?
Kelly Dack: You could say that great things happen when project stakeholders get together. Everybody can represent their own part of the project and come together. I teach the Certified Interconnect Designer (CID) class, and the CID principles teach us that at the start of a project, you've got to bring everybody together and put values on everything: test, mechanical, components, fit, performance, and all the other design forces. They all have to come together, and the project manager has to put weight on each of those things.
Shaughnessy: So, the CID provides a guideline for setting up a collaborative environment?
Dack: Absolutely. CID has a graphic that really hits the nail on the head. It is a picture of a table, with chairs around the table representing each stakeholder: testability guys, test engineer, mechanical engineer, PCB designer, electrical engineer, manufacturing engineer, and supplier management, who have to go buy all these parts and source the parts. This is the foundation of what needs to happen. The IPC CID program preaches that it takes a village, so to speak—a team of all the stakeholders—to buy in to make the product successful down the road. That’s basically the start of any conversation on collaboration.
Ideally, the project manager is the one who will pull all the stakeholders together, including the designer and engineer, so they can hear from each other. For instance, does this board need to be 100% testable? For one recent board, we went through several prototype development layout cycles just to get the circuit performance dialed in. Tragically, we found out after the layout was complete and functioning that it had to be 100% testable because the customer was going to pay for a test fixture. Design for testability (DFT) must be implemented at the start of design, or there will be no room to add the test points.
The worst time to implement DFT is after a board design is locked up and performing well. So, to prevent this from ever happening again, what did we do? We created an internal standard that said all boards shall be 100% testable. That’s good, but the problem is that this takes a lot more time and rules checking because we have introduced test points that could affect performance.
To read the entire interview, which originally published in the June 2024 Design007 Magazine, click here.
