Design Guidance

2022-11-08 BEST

Calculating the Bend Radius

Bend radius is the minimum degree the flex area can bend. Use the chart below to calculate bend radius on your next design.

 

Rigid-Flex Table

 

Rigid-Flex Board (not bending)

 

Rigid-Flex Board (bending)

Knowing the life cycle bending times of your flex PCB is crucial to your design. If a flexible board is bent more times than the design allows for, the copper will begin to stretch and crack.

Semi-static: A flexible PCB that flexes a maximum of 20 times.

Dynamic: flexible PCB that is regularly flexed and twisted.

Neutral Bend Radius

The neutral bend radius is the plane where there is no tension or compression when the circuit is flexed. Designing a balanced construction is the best way to center the neutral bend radius. Placing copper plane layers near the center of the material stack also keeps the neutral bend radius centered.