Conductor Routing on Flex Boards

摘要

Flex pcb routing shares many of design rules as rigid PCB routing, with a few extra rules that apply specifically to areas of the circuit that will be flexing. The "extra" rules are: 1. Keep plated vias out of flexing areas. When a circuit is bent, there will be stretching and compressing forces that come into play that can wreak havoc on plated vias. Put 'em somewhere else! 2. Conductors should be routed through flexing areas perpendicular to the bend. For a single flex to install this is not especially critical, but if the flex will be subjected to multiple flexing cycles during its service life, this becomes a concern. 3. Avoid directional changes in flexing areas. If the preceding rule is followed there won't be an issue with this. Again, this is not critical in a flex-to-install application, but it is if there will be more than a few flexing operations. If direction changes absolutely cannot be avoided, use an arc rather than a sharp corner. The larger the radius of the arc, the better.