Are vias reliable in flexible circuits?

As we all know, flex PBC is flexible. I am curious about the reliability of vias in it. Is it easy to break?

As a former circuit board (and flex circuit) designer, I would expect vias in flex circuits to be about as reliable as in more traditional (rigid) laminates. Factors that would influence reliability include:

  1. The amount of vibration and mechanical stress applied to the flex over its lifetime
  2. The thickness of the wall plating in the plated through holes (aka vias)
  3. The quality of manufacture (a flex circuit built by a fab that has experience with the technology will more likely build a reliable part)
  4. The layout of the via pads themselves

In the case of item #4, I would advocate for a “teardrop” shaped pad, to smooth the transition from the trace to the via pad.

This will tend to reduce fracturing where the trace enters the via pad on the flex circuit.

Read More: What is Flexible PCB

#PCB Assembly

Picture of Oliver Smith

Oliver Smith

Oliver is an experienced electronics engineer skilled in PCB design, analog circuits, embedded systems, and prototyping. His deep knowledge spans schematic capture, firmware coding, simulation, layout, testing, and troubleshooting. Oliver excels at taking projects from concept to mass production using his electrical design talents and mechanical aptitude.
Picture of Oliver Smith

Oliver Smith

Oliver is an experienced electronics engineer skilled in PCB design, analog circuits, embedded systems, and prototyping. His deep knowledge spans schematic capture, firmware coding, simulation, layout, testing, and troubleshooting. Oliver excels at taking projects from concept to mass production using his electrical design talents and mechanical aptitude.

What Others Are Asking

How can I determine BGA land pad diameter for given ball diameter?

I’m working on a project which requires the use of a CSP package. The product’s datasheet provides ball pitch and ball diameter but nothing about the preferred land pad diameter.
How can the pad diameter be worked out from these figures assuming an NSMD land?

I forgot a resistor on my PCB prototype – how do I add one in?

I need to add a resistor into a data line on my project. The data line is a trace and carries low speed data. A through-hole resistor will be fine. The pins for both ends of the trace are exposed, but how do I add the resistor and remove the trace?

Read Detailed Advice From Blog Articles

The Essential Guide to PCB Controllers
Will Li

The Essential Guide to PCB Controllers

PCB controllers enable the smarts in electronics of all types, from tiny wearables to industrial robots. These ingenious chips act as the brains of countless

Scroll to Top