0
\$\begingroup\$

I see many custom designed FFC cable in laptops and tablets like the yellow and black cables on my UX305 laptop (shown below).

  1. How can I design a similar FFC cable? Is it the same as PCB design layout?
  2. How much it cost for a single layer FFC with 1.5" length on a small run (10 to 20 pieces.)
  3. What design rules should I consider moreover to normal PCB to get it work with a FPC connector.

enter image description here

\$\endgroup\$
3
\$\begingroup\$

No big deal. You design them like regular PCBs using Altium or whatever and follow certain guidelines. Typically one or two layers can be inexpensive. Search makers for their manuals and capabilities. You will need to be careful in specifying thickness and stiffener if you want to plug into an FPC connector.

Altium in particular has a feature that allows 3D folds so you can see what the finished product will look like.

Starting price is about $100 USD FOB for 5 or 10 pieces if you are willing to deal directly with Chinese suppliers.

Unfortunately rigid-flex is not nearly in that category yet, it cost several thousand USD last time I bought a smallish quantity (but worth it in that case). For that amount of money you can get very nice rigid boards with microvias, buried vias and many layers in a custom stackup.

I don't think flex boards with a huge number of layers are very practical- they will be too stiff, but you can make rigid-flex with the rigid part having many layers. I understand the different CTEs and other issues make it kind of hit and miss and they may have to iterate to get decent yield on the first run (and there can be a LOT of steps involved (it's even possible to design boards that cannot be manufactured because of the drill steps).

Sometimes it's recommended to put two flex cables (each with half the layers) overtop of each other to get a smaller minimum bend radius. You can do that with rigid-flex.

\$\endgroup\$
3
  • \$\begingroup\$ Thanks. your answer sound more reasonable. I have one more question. The FFC cable have some blue ribbon attached to each ends. What does it do and does the manufactures capable to do the same? How can I define that in altium? \$\endgroup\$
    – pazel1374
    Mar 30 '18 at 7:47
  • \$\begingroup\$ more over I dont need multilayer FPC. only a single layer will work out for me \$\endgroup\$
    – pazel1374
    Mar 30 '18 at 7:48
  • 1
    \$\begingroup\$ Blue looks like a stiffener. It is a plastic bit that is bonded to the circuit near the end where it will plug into a connector. You can show the outline on a mechanical layer and define the thickness in your notes. The total thickness must be within the allowable range for the connector. \$\endgroup\$ Mar 30 '18 at 19:43

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.