Design for Excellence – Definitions and Checklist
Bringing an electronic product to mass production is not easy. From actual design of your product to cleanliness of your overall documentation package, a number of challenges have to be carefully addressed before even thinking about discussing manufacturing.
DfX: the safety check of your product
Design for Excellence (or Design for X, or DfX) is basically a set of services aiming at analyzing the way your product has been designed. It encompasses Design for Manufacturing or Manufacturability (DfM), Design for Cost/Procurement (DfC/DfP), Design for Assembly (DfA) and Design for Testability (DfT). If you’re really into knowing all kinds of acronyms related to Design, there is a much more complex definition available on Wikipedia.
DfM — Design for Manufacturing or Manufacturability
Your EMS partner will analyze the circuitry and design/layout of your printed circuit board, making sure the footprint is in line with the reference designators found in your BOM (or Bill of Materials). By the way, your BOM will need to be clean and precise if you expect any CM/EMS to understand it and price it quickly. Some good tips on this very topic are available through this interesting article on ElectronicDesign.com. Each and every project should go through this stage, to make sure there are no issues encountered while kicking off the assembly of your printed-circuit board (PCBA).
DfC/DfP — Design for Cost & Design for Procurement
With the increasingly volatile electronic components market, the Design for Procurement / Design for Cost stage is important in identifying and qualifying alternate parts which would perform the same function as the one you’ve already identified. This is more important for critical items such as micro controllers, ICs or memories. Further than making sure you have alternatives in case of a shortage, it is also a good way to make sure you reduce the lead times as much as possible for a particular item, by identifying different sources for this very part. Such challenges are often overlooked… until it is too late to react, source and qualify an alternate when you’re just being notified about a shortage on one your components, delaying the whole production process.
Design for Procurement is also valuable at the end of life (EOL) of your product, to make sure to avoid components’ obsolescence.
DfT — Design for Testing or Testability
At the printed-circuit board level as well as at the final assembly (also called Box build), your product will need to be tested while in mass production stage. Design for Testing/Testability helps to analyze test coverage of your printed-circuit board layout, and develop the right tools which will actually test the boards while in production. This is a critical part of the manufacturing process of your products and if large corporations have integrated this process into their design, it is often neglected by most of the hardware startups especially when working on the first generation of the product.
DfA — Design for Assembly
The focus here is on mechanical items such as plastic casing/enclosures, sheet metal or CNC machining parts, whatever is going to be the “exterior” of your products: Design for Assembly (or DfA) aims at making sure your product is easy to assemble. Reason why? Even with automation and industry 4.0 bringing new ways of assembling/manufacturing products, in most of the countries your product will still be assembled by humans. Therefore, a tiny little discrepancy in measurement can make your product a little longer to assemble, definitely impacting your production rate (and cost). To me, this is a design step not to miss at all, especially for complex products with numerous mechanical items (screws, clips, items to glue, etc.)
Once all these steps are accomplished, you can envision a smooth new product introduction (or NPI) and expect a limited number of surprises to show up (even though surprises are many in the Manufacturing world).