Buyers are often surprised when we quote 18 to 20 weeks for an outsourced electronic design project. But when you understand that failing is a big part of the process, you can start to see why it takes so long. More importantly, you can predict whether the quoted lead time is realistic and achievable.
This lead time is typical for a moderately complex product in a commercial, industrial, or medical system. It includes circuit design, printed circuit board layout, and a working prototype.
When we get a request for quote (RFQ), our engineers spend several days studying the requirements and brainstorming solutions. If we can see at least one promising approach, we send a proposal. We will be fairly confident that it will work… but we won’t know for sure until we test it.
Weeks 1-3: Circuit design (the fun part)
Designing the circuit takes only 2to 3 weeks. This is the fun part. It is challenging and creative. There is no one “right” approach for any function, only some common approaches, with different advantages under different circumstances. Experienced engineers are more likely to choose an approach that starts them down the right path. Look for designers with experience in circumstances similar to yours, including market and technology (power, analog, etc.).
From this starting point we evaluate myriad tradeoffs: key performance requirements, cost, component availability, reliability, space limitations, manufacturability and more. Here, even the most experienced design engineers benefit from collaboration with other engineers. Formal and informal team input can save a designer from spending too much time developing what would ultimately be the wrong approach. Look for an engineering team with a culture of collaboration.
Component selection is a big part of circuit design. This gets easier with experience, as an engineer builds a mental library of familiar components and their real-world performance. The most effective engineers also avoid sole-sourced parts, know which parts are affected by shortages, and make sure substitutes are available. Look for a design partner who can demonstrate they understand this.
When the schematic is finished, we have a pretty good idea what it will do. We run simulations on areas we’re not sure about. We have a formal design review with the full engineering department. But to see what will really happen we need to lay out the board, build some units, and test them.
Weeks 4-20: Test, fail, revise, repeat
Now the fun part is over, and we spend the next 10 to 20 weeks failing.
Even with careful design and simulation, a circuit almost never works perfectly the first time. Maybe it gets too hot, or a signal is too noisy, or the timing is off, or a function works under most conditions but not all. So we embark on a series of experiments to figure it out. This entails:
- Analyzing the problem
- Forming a hypothesis
- Proposing a solution
- Making the change
- Testing the revised board
- Repeating until the problem is fixed
Then we move on to the next problem and repeat the cycle. The more complicated the circuit, the more cycles there are.
Troubleshooting is not as much fun as design, and people usually underestimate how long it can take. The biggest danger is failing to question your data and basic assumptions. A team approach can help an engineer avoid this pitfall. Look for a culture that encourages making and learning from mistakes.
Additionally, look for a design services partner with in-house manufacturing capabilities, even if you will manufacture the design yourself. In-house manufacturing engineers can provide faster turn-around of each revision and expert guidance on manufacturability.
Is it realistic?
So given that only 10% of our time is spent on design and 90% on troubleshooting, 18 to 20 weeks for a complex electronic product should look a little more realistic. Whatever lead time you’re quoted, it’s a good idea to ask questions about how your partner estimated it. You can have greater confidence it is achievable if your partner has:
- Experience in your market and the technologies you need.
- A team of engineers and a culture of collaboration.
- A commitment to continuous learning about the latest components and design techniques.
- Experience with manufacturing, or in-house manufacturing capability.