Introduction
Rigid-flex PCB technology offers tremendous benefits in terms of reduced weight, space, durability, and reliability. Today’s small lightweight consumer electronics products are best implemented with rigid-flex technology, however, there can be many challenges in achieving successful rigid-flex PCB designs. This guidebook is attempt to clearly explain the materials, processes and design issues in a way that will enlighten PCB designers of any level. This paper highlights several key considerations for rigid-flex design.
Rigid-flex PCB is a time-proven, well-understood technology initially used within the military/aerospace industry decades ago.
Today it is recognized as the ideal solution for contemporary small form factor, highly durable, and lightweight electronic products such as wearables, medical devices, and mobile wireless products. However, as many PCB designers contemplate designing rigid-flex PCBs for the first time, several challenges come to mind:
- - How much will rigid-flex cost to fabricate and assemble?
- - How are the dissimilar rigid and flex sections described as one PCB assembly?
- - How are the different rigid and flex materials and layer specifics managed and communicated to a fabricator?
- - How can the range of motion and critical folded states be modeled and verified?
- - How is placement and routing within flex regions different from that of traditional rigid PCB?
These and many other questions reflect the challenges of rigid-flex PCB design.
Yet there are aspects of rigid-flex technology which could be pot-holes in the road for newcomers. So it’s wise to first understand how flex circuits and rigid-flex boards are actually made. From there we can look at the design issues imposed by the materials used, and the fabrication processes employed by most rigid-flex PCB manufacturers. And from there, we can find a clear path to discover the best practices for rigid-flex PCB design.
This guidebook is attempt to clearly explain the materials, processes and design issues in a way that will enlighten PCB designers of any level, who have not had a great deal of experience - if any - in designing of flex or rigid-flex circuits.
We hope is that this guidebook will form a good enough introduction to rigid-flex PCB design that more readers will see the technology within reach for their own design projects, and that a result overall will be increased adoption. And, with increased adoption there should be decreased costs, which in turn will further increase access for more electronic product developers to utilize rigid-flex boards.
