Rigid-flex DFA

Estimated reading time: 1 minute

Rigid-flex assembly brings its own set of issues, but designers can do quite a bit to make things easier on their downstream brethren. We asked IPC instructor Kris Moyer to give us the lowdown on DFA for rigid-flex circuitry.

Kris, what are some of the unique challenges related to assembling rigid-flex circuits?

There are several challenges to assembly of rigid-flex boards. First there is the alignment issue of the different sections of the boards. With a rigid board, the individual boards can be removed from the fabrication panel and run through the SMT assembly line without much problem, as long as the board is of sufficient size. In this case, the relative position of all the individual parts on the board remains consistent. But with rigid-flex, after the board is removed from the fabrication panel, the individual boards can move and rotate relative to each other within the limits of the flex material. This makes the placement of parts difficult to control. To overcome this, the board must be held in a restrained condition throughout the assembly process. This will require either the fabrication of a custom fixture to hold the board restrained during assembly or the design of temporary removable restraining mechanisms (rails) into the design of the board.

To read this entire conversation, which appeared in the September 2023 issue of Design007 Magazine, click here.