Let’s Look At Wearable PCBs Once Again
We talked to you about wearable PCBs in our November TOTM. But that’s not the end of the story since there’s so much to say about those particular very small PCBs. And we have the experience to share new developments with you.
We’re seeing increasingly greater interest from our customers for taking the next big leap into wearable products, regardless which markets they’re pursuing.
In this next round, we focus on the key considerations, you, the OEM, should keep in mind to make your wearable product more successful during PCB design, assembly, and manufacturing.
The foremost thing to keep in mind is there are multiple differences between conventional and wearable PCB design and manufacturing. That doesn’t mean PCB design and manufacturing are completely revolutionized.
However, wearable PCBs can be called a game-changer. For example, rather than the larger rigid boards, we’re now dealing with considerably small flex circuits, but not the one- to two-layer variety. Now, we’re involved with multiple layers and RF circuitry.
In the meantime, here are some tips and hints to help you gain a broader understanding of important wearable PCB considerations.
- Package selection plays a critical role in wearable PCB manufacturing. Make sure you’re choosing the right ones for your particular application.
- You have to very carefully spec out components for low power, low current requirements for specific applications.
- The same holds true for the selected µP. Currently, 8-bit suffices. But later on 16- or 32-bit may be required.
- Before, there were five to six mil spaces between traces; now with wearable PCBs, there are two to three mil spaces between traces, posing manufacturing challenges.
- It’s of the utmost importance to have an experienced PCB designer who fully understands tolerances when using die attach or wire bonding for micron accuracy at bent angles.
- Work with your EMS provider to define chemistry of the epoxy used with flex circuits. Here, experience is important to conduct experiments to get to the right epoxy.
As we move further into wearable PCB technology, we’ll share our experience with you. We’ll bring you the latest, most advanced developments based on practical design and assembly work we perform in wearable PCBs.