Documentation

Flex-rigid design

Starrflex .jpg

Image: Flex rigid design

PCB in flex-rigid design are often combinations of rigid (FR4) materials fixed to flexible parts (like a foil). There are various techniques of constructive setup. The foil for example can be glued to the rigid parts. In your TARGET 3001! project you need to define which outline(s) refer to rigid parts and which outline(s) refer to the flexible parts. Imagine a fourfold multilayer board setup with the upper layers made of foil. The rigid parts now get laid back according to the desired flexible area. The following sketch will illustrate this:

StarrFlex e.PNG


Start in TARGET 3001! with the definition of your layer setup as a "4fold multilayer". That means you add inner layers 10, Copper inside and 13, Copper inside. The foil would be represented by layer 16, copper top and 13, copper inside while the rigid parts would be represented by layers 10, copper inside and 2, copper bottom.

Starrflex 2ae.jpg
Click on image to enlarge.


Now define the outline of the inner layers which later appear as foil. For doing so you need a new, self made layer describing the outline of the flexible parts. In short we call it: Flexoutline. How to create a new, self made layer function is illustrated by the following image:


Starrflex 1e.jpg
Click on image to enlarge. (M2 means "right mouseclick")


Now draw the complete outline of the foil upon layer "Flexoutline". That's how it might look like in TARGET 3001!:


Starrflex 3e.jpg
Click on image to enlarge.


Now construct the rigid parts of the PCB by several outlines upon the "normal" outline layer 23, Outline. That's how it might look like in TARGET 3001!:


Starrflex 4e.jpg


Both layers together look like this (tick "Colormix when covering (PCB)" in menu "Settings / Settings/Options"):


Starrflex 5e.jpg


Now assemble your board on the rigid areas with the parts you desire. Place tracks on the foil layers (16 and 13) if you want to lead them from rigid to rigid via the flexible area, see following image:


Starrflex 6e.jpg


You should take in account to discuss with your PCB house which design elements are needed so that you can do your design according to these requirements. Sure this will depend on the technique of the flex-rigid construction in particular. The above is only an example.