Issue link: https://iconnect007.uberflip.com/i/1470111
30 DESIGN007 MAGAZINE I JUNE 2022 for a mechanically drilled single-lamination PCB vs. laser-formed microvias on a board that is sequentially laminated. Accordingly, not only are multiple rule sets based on the manufacturing processes required, but you also must consider that each fabricator you work with will have different process capabili- ties, and therefore different constraints. It is valuable to understand the true objec- tive of DFM, which is to help designers opti- mize their designs for manufacturing dur- ing the first release. Nobody can afford to go through three or more revision spins to move from prototype to volume production. Designers want to accelerate the new product introduction (NPI) process and get to market earlier. To accomplish this, visibility is needed into the issues that will impact yield, cost, and reliability during the initial design process— not aer each step of the production ramp-up. us, the constraint sets that are provided by the manufacturer need to include the level of detail that informs the designer of where the design could be improved to manufacture it at a lower cost or with greater reliability. Manu- facturing is a process with tolerances—it's not a binary pass/fail. How the process constraints are communi- cated is also equally important. Understand- ably, many manufacturers treat their process capabilities as confidential information, and they want to control with whom they share this level of detail. So, it becomes critical that the digital means of sharing that information be protected and kept within the manufactur- er's control. e design OEM needs to be able to benefit from access to the manufacturer's constraint set, but they don't actually need to see what's driving it. I use the analogy of ride- share programs. You derive the benefit of get- ting a ride from point A to point B, but you don't need to look under the hood of the car to get there. What is paramount is that your DFM analysis is aligned with your supplier's DFM analysis. It needs to be easy for the manufacturer to maintain its constraint set for the benefit of its customers. As process capabilities improve, the manufacturer needs a platform that allows for posting its updated capabilities for custom- ers to access immediately. Today, it's a painful "drip," inconsistently communicated. Let's keep in mind that DFM entails all aspects of the manufacturing process—bare- board fabrication, PCB assembly, electrical test, stackup planning, and even component sourcing. A true DFM collaboration platform can arm designers with a digital twin for each of these disciplines in a manner that integrates seamlessly into their PCB flow. Collaborat- ing on the stackup recipe before a designer is asked to lay out a board is as critical as the con- straints they design to directly impact the cir- cuit's performance. If your goal is to optimize your designs for manufacturing on the initial release, it is imperative to design and analyze using the actual stackup materials that will be used to fabricate the PCB. As I have mentioned previously, DFM is not a binary process. Severity indicators existing within "grey areas" are a vital part of under- standing and making informed decisions for manufacturing. A designer, for example, would benefit from knowing that a placement deci- sion they made for a component will cause that component to be placed manually by the con- tract manufacturer (CM). e CM can build it, but the extra touches will cost the OEM more. e concept even applies to rework. A CM It is valuable to understand the true objective of DFM, which is to help designers optimize their designs for manufacturing during the first release.