Rigid Flex prototyping

[ArticCynda]

Hi everyone,

I got into rigid flex boards lately because of the space saving advantages in area constrained designs, and I'm currently finalizing my first board.

Unlike with standard rigid manufacturers, which are so plentiful around that double or even four layer board are extremely cheap (I prefer ITead Studio if I can afford to wait a few weeks), I have yet to find a manufacturer allowing me to upload the layer stack of my 4 layer rigid flex board and make one or two pieces of it. They're all either horribly expensive or can't provide small quantities for prototyping.

Any advice on where to get rigid flex prototype boards manufactured?

Thanks in advance!

 

[Dan Mills]

Small quantity flex rigid IS horribly expensive, I ususally use Wurth for small quantities and short production runs, but yea, not cheap in tens, but they can do amazing things.

Top tip for flex rigid, solid ground planes are not a good idea on the flex (It then doesn't!), and keep vias away from anywhere the thing gets bent, even microvias suffer if on a bend line.

Regards, Dan.

 

[marce]

If your flex circuit is a static design (bends into position once) then you may have to use a solid ground plane for high speed or current requirements. I had to do some with 2oz copper solid plane...they didn't flex much, you can also get up to 7oz flexis often referred to as sculptured circuits, these again bend into position once and stay there.
The fabrication of flex circuits is different than that of rigid PCBs, one of the main costs is the tooling to cut the flex circuit base material to shape.


A design guide or two:
https://flexiblecircuittechnology.com/flex4/
https://www.lboro.ac.uk/microsites/...e-circuit-technology-and-its-applications.pdf
**broken link removed**

 

[ArticCynda]

Thanks for the useful resources on getting me started with flex designs, guys!

I've been looking around, and for 2 or 3 prototype boards the lowest quotes I got are 600 EUR and up. Is this normal? I don't know if I'm allowed to ask in this forum (due to "advertisement" and related rules), but where do you let your rigid flex boards be manufactured, Marce?

 

[ArticCynda]

Also, is it normal that most manufacturers are demanding me to submit my gerber files before they can provide me with a quote? I've never had that with rigid boards before.

 

[marce]

Flexis are more complex so yes, it makes the process more accurate.