There are numerous, different structures available. The more common ones are defined below:
Traditional rigid flex construction (IPC-6013 type 4) Multilayer rigid and flexible circuit combination containing three or more layers with plated through holes. Capability is 22L with 10L flex layers.
Asymmetrical rigid flex construction, where the FPC is situated on the outer layer of the rigid construction. Containing three or more layers with plated through holes.
Multilayer rigid flex construction with buried / blind via (microvia) as part of the rigid construction. 2 layers of microvia are achievable. Construction may also include two rigid structures as part of a homogeneous build. Capability is 2+n+2 HDI structure.
In our FAQ about PCBs (printed circuit boards) you can read more about the structures and see their technical illustrations.
Please contact your local NCAB Group company if you need further information or assistance, we are happy to help you.
|Feature||NCAB´s technical specification for Rigid-flex PCBs|
|Number of layers||4-16 layers|
|Technology highlights||Mixed materials including RF and high speed, standard FR-4, polyimide flex. Adhesiveless or adhesive based polyimide flex constructions, with cover coat or flexible solder mask materials.|
|Bending performance||Based on the specific design, the bend performance can range from a basic 90 °bend to fit to a full dynamic flex with 360° range of motion in the flex tail that will withstand continuous cycles throughout the product life.|
|Bend features||Bend radius controls the flexibility of the flex portion of the board. The thinner the material the lower the bend radius and the more flexible the flex section.|
|Materials||RA copper, HTE copper, FR-4, polyimide, adhesive|
|Copper weights (finished)||½ ounce, 1 ounce, 2 ounce, 3 ounce|
|Minimum track and gap||0.075mm / 0.075mm|
|PCB thickness||0.4mm to 3mm|
|PCB thickness in flex section||0.05mm to 0.8mm|
|Maxmimum dimensions||457mm to 610mm|
|Surface finishes available||ENIG, OSP Immersion tin, Immersion silver|
|Minimum mechanical drill||0.20mm|
To prevent getting it wrong from the start, we have put together our PCB design guidelines, to use as a checklist.