New to PCB Design - Seeking Guidance on KiCad and Rigid-Flex PCBs

Hi everyone,

I’m an amateur in PCB design and have recently chosen to dive into the KiCad ecosystem. I have a basic understanding of how PCBs work, including the concept of multiple layers in both rigid and flex PCBs. However, I’m struggling with designing them and integrating them into a unified circuit system, or I can say, I don’t have any knowledge on how to.

Specifically, I need help with:

  • Understanding and creating vias
  • Routing techniques
  • Designing a circuit that combines both rigid and mostly flex PCBs

I’m particularly interested in flex PCBs and aim to create a microcontroller board that leverages the benefits of both rigid and flex technologies.

Could anyone recommend resources or books that cover:

  • Learning KiCad Designer
  • Rigid PCB design
  • Flex PCB design

Any advice, tutorials, and website or book recommendations would be greatly appreciated!
Thanks in advance for your help!

To learn KiCad just read its documentation.

To learn PCB design you can read the articles I gave links to them long time ago:

About Flex PCB I can say nothing - I never used them.

There is a lot of good, reliable, information on flex by searching: “Flex PCB design guidelines”.

Flex PCBs are always a bit non standard. You have to have have a vendor in mind and follow their requirements

Flex PCB’s are not very special for the part of the PCB design. The biggest differences are:

  1. You have to be careful with sharp corners, width changes in tracks and holes in the flex, because any stress riser point can be a place where the flex breaks over time (this is mostly important for flex PCB’s that get bent a lot during their lifetime).
  2. When ordering the PCB, you have to fill in some other checkboxes compared to a “normal” PCB.

You can enter PCB thickness and select the material in PCB Editor / File / Board Setup / Board Stackup / Physical Stackup, but I am not sure at all your PCB manufacturer will respect these settings.

Rigid-Flex goes a step further. You have to specify which parts of the PCB are rigid, and which parts are flex (Note there is also a Semi-Rigid PCB production process, which is cheaper, but the PCB can be bent only a few times, it’s meant for folding the PCB once during manufacturing) Ordering this type of PCB is (as far as I know) mostly non standard, and you likely have to tell the PCB manufacturer which parts are rigid, and which parts are flex. This information then likely gets interpreted by a biological entity called a “human being”, and translated to whatever their production process is. This is a quite cumbersome and archaic process, and it’s a clear sign the world has not evolved sufficiently yet.