BANNOCKBURN, IL – The industry standard that establishes requirements for the design of flexible and rigid-flex printed boards has been updated to its C revision. IPC-2223C, Sectional Design Standard for Flexible Printed Boards, includes new design guidance and requirements for preformed bends, irregular folds and creases, staggered flexible layer bands as an alternative to “bookbinder” designs, and depanelization methods for flexible and rigid-flex array sub-pallets, as well as information on the use of adhesiveless materials.

It also includes, as Appendix A, a new design tutorial with guidance on material selection, size and shape of flex circuits and fabrication allowances.

Technologies such as blind, buried and microvias that are the same in flex and rigid printed boards, are not included in IPC-2223C. Instead, users are referred to other standards such as IPC-2221 and IPC-2222 that address these technologies.

However, one aspect of rigid printed board technology that is included in the standard is the connection between rigid and flex printed boards.

The revision also includes sections on strain relief fillets applied at the rigid-flex interface and other factors unique to printed boards that have as many mechanical factors as electrical design points.

For more information, visit www.ipc.org/2223.