Oftentimes, in terms of PCB design, we are tasked with fitting a square peg into a round hole. Fitting thousands of various components onto a board no larger than a dollar bill, and maybe even a quarter, we always seem to be limited to the 2D plane of predetermined space within our
equipment or device.
We’ve all been there: after putting the finishing touches on a PCB design, you take a look at the space requirements of the device only to find that you’ve exceeded what is allowed in. Now it’s back to the drawing board.
Without any alteration to this 2D plane, we can certainly make efforts to condense into a higher and higher density of interconnects making it an ultra HDI PCB. We could increase the number of layers of the board incorporating the use of multilayered vias. We might even be able to push the borders of our edge clearance tolerances allowing for more components to be crammed on to our plane. Or, we can explore the benefits of rigid flex PCB design.
What is Rigid Flex for PCBs?
As the name implies, rigid flex PCBs are comprised of both rigid and flexible PCB material. The rigid portion of the PCB as our familiar-looking board housing many of the components. The flex portion of the PCB is (again, as it sounds) a flexible material that is designed to bend, twist, roll over, sit, and play fetch… wait… am I mixing things up?
Flex PCBs alone are pieces of marvelous engineering. Allowing you to even house the components onto this flexible material, they can fit into nearly any shape and application (however mounting these to your device can be a bit tricky as there is no solid “backbone” to fall back on). Rigid flex takes things to another level, allowing you to firmly mount the rigid portion on to your device and use the flexible portion to expand space requirements to 3D.