Rich experience flex circuit manufacturing engineer overlaps a minimum of 0.762 Millimeters.
If you do not overlap stiffener and coverlay termination points, the resulting may stress points.
So all rigid flex circuit manufacturing process must care about the stiffener overlap.
The function of rigid flex circuit stiffener
During rigid flex circuit manufacturing process, place stiffener is the important factor.
But why we need a stiffener, or what is the function of rigid flexible PCB circuit stiffener.
PCB stiffeners can be used to reinforce the areas where components will be assembled.
Because during rigid flex circuit manufacturing assemble process require high reliability.
This means flexing circuit areas will don’t need a stiffener.
Both sides need rigid flex circuit board stiffeners
This is a special situation for rigid flex circuit manufacturing.
And not each rigid flex circuit board needs both side stiffeners.
If designers require assembly both sides rigid flex circuit stiffeners.
It will be required two laminations on the top and the bottom of the circuit.