Do the conductors pass through bend areas perpendicular to the bend line?
Conductors should always be routed through bend areas as close to perpendicular as possible. Are there plated through holes in or near a bend area? Plated through holes should be kept out of the bend areas whenever possible. It is difficult to predict how stretching a conductor on one layer and compressing a conductor on another layer will affect the plated hole that interconnects the two layers. Since the end result is unpredictable and since a defect would be very difficult to detect, it should be avoided. Are termination pads near bend areas filleted? If the circuit will be bent within 1 in. of termination pads, fillets should be placed at each conductor/pad interface. Pad filleting is a good practice on all pads on flex circuitry, but is particularly important near a bend. An unfilleted pad represents a concentration point for stresses. This is especially true if the cover opening does not entirely capture the pad and exposes the conductor/pad interface. Stresses from a bend are no
