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

[sammtan]

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!

[Piotr]

To learn KiCad just read its documentation.

Documentation | KiCad

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

Decoupling capacitor via placement

I didn’t read that book but I suppose you can replace it with: I think it is enough for most pcb designers.

Decoupling capacitor via placement

About 2004 I found an interesting serie of EMC articles by Keith Armstrong (for many years I didn’t know if Keith is a woman or men name). Later they became no accessible, but when I tried to find them few years ago I found them once more: http://www.compliance-club.com/pdf/DesignTechniquesPart1.pdf http://www.compliance-club.com/pdf/DesignTechniquesPart2.pdf http://www.compliance-club.com/pdf/DesignTechniquesPart3.pdf http://www.compliance-club.com/pdf/DesignTechniquesPart4.pdf http://www…

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

[jmk]

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

[davidsrsb]

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

[paulvdh]

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.