DFX – Design for Excellence Explained in 4 Minutes
What is DFX?
DFX stands for Design for eXcellence.
In practice, DFX refers to the application of different sets of guidelines throughout the product development process, to ensure a product meets its design requirements.
Now, there aren’t really any DFX guidelines, because the X is simply there as a placeholder. DFX is usually broken down as follows.
The most common DFX are
- Design for manufacturing (DFM)
- Design for Assembly (DFA)
- Design for Manufacturing and Assembly (DFMA)
- Design for Reliability (DFR)
- Design for Supply Chain (DFSC)
- Design for Testing (DFT)
All those DFX above, in practice, translate into guidelines and more guidelines applied to a specific product and based on its requirements.
You can then think of DFX as the central concept from where all the different DFX guidelines and strategies fan out.
DFX is sort of a general concept to remind you, hey! before you’re done designing an electronic, make sure it’s designed to pass tests, or that it’s designed using components that are easy to be supplied.
Having a DFX set of mind means you’ll design a product knowing the end requirements, of all sorts, it’ll have to meet to be a success.
This brings you the following benefits
1- A product design for manufacturability
This is DFM, which can be summarized as designing a product taking into account, from the start, your manufacturing plant’s capabilities and availability of components and parts.
2- A product that is designed to pass tests.
This right here is quite important.
We work designing and manufacturing electronics, and something that can easily become time-consuming is testing for certifications.
Especially when we have to pass EMC (Electromagnetic Compatibility) tests.
If by the time we get to testing for electromagnetic compatibility the waves are still not within limits, then we’re in for a several months delay before we can release the product to our clients.
We need to find the place where the noise is and most likely do a redesign of the board.
That’s why from the start, we like to know what certifications we’ll need to pass so we can “Design for Tests”
By designing for tests, we ensure a lower use of engineering resources and a faster time to market.
3- A product design for assembly.
DFA also falls within DFX.
DFX then seeks to simplify the product so that the cost of assembly is reduced.
A simple to assemble product means fewer chances for assembly operators to make mistakes, which at the same time it translates into lower RMAs requests.
4- Improved product lifecycle
Designing for the supply chain, part of DFX, ensures you select components and parts with the shortest lead time possible.
If you choose components for your PCB without considering supply availability on large scales, you might find yourself with one or two components with lead times of up to 32 weeks; this would put any manufacturing operation on hold.
And it’s not just about having all the components and parts for manufacturing, you must also ensure a constant supply of spare parts and components for product repairs.
Chances are, that even with the most outstanding quality control measure in place, some of your products will still be faulty when they reach the users’ hands.
For these cases, you might want to offer repair services, which means you’ll need extra product parts and components for such a task.
Or perhaps, it’s not a matter of faulty products, perhaps your product will require the use of a special battery throughout its product life, well, you must ensure a constant supply of such a battery.
By now it should become clear that DFX, in a broad sense, is about foreseeing the future requirements of a product throughout its product lifecycle and designing for it.
DFX and Product Development
DFX is present throughout the complete product development process, or at least that’s how it’s supposed to be.
Remember that DFX is a broad concept that encompasses:
- DFR (Design for Reliability)
- DFSC (Design for Supply Chain)
- DFT (Design for Test)
- DFM (Design for Manufacturing)
- DFA (Design for Assembly)
- DFMA (Design for Manufacture and Assembly)
10 DFX Guidelines
1- Avoid strange PCB forms and shapes or out of the ordinary PCB constructions to make up for lack of space.
2- Make the product design as simple as possible to minimize cost and maximize quality and reliability.
3- Use advanced high-density interconnection technologies only when extremely necessary and based on quantitative argumentation.
4- Minimize the number of component types in the PCB.
5- Aim for clarity; specify all product aspects. Do not assume that people will know what to do. Lack of specification leads to bad quality, non-reliability, and, product variability.
6- Do your homework and be critical when selecting components and parts suppliers. You’d be surprised at how many companies end up buying components from resellers that provide no support after purchase.
7- All design choices must be reviewed by all members of the product development team, consider reusing previous design solutions.
8- Manual work leads to high assembly cost, variable quality, and reliability risks. Always design for automated assembly and machine soldering.
9- Ensure everyone in the team understands that they have to adhere to design guidelines. There’s a reason for guidelines to existing; they make all technological, manufacturing, quality, reliability, and other product requirements become a reality.
10 – Make PCB testability paramount early in the design, before PCB layout. Always keep Design for Testability (DFT) and Design for Repair requirements in mind.