52 DESIGN007 MAGAZINE I OCTOBER 2023
dimensions or "degrees of freedom." A rigid
stackup, for example, can easily be viewed in
2D, and that world is relatively easy for most
electrical hardware engineers to understand
and manage. You have impedance, frequency,
and loss and then physical and electrical
parameters that drive them. When flex sub-
stacks come into the picture, the fact that the
flex portion needs to bend turns it into a 3D
mechanical engineering problem that takes
some time to learn.
Rigid-flex DFA E
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.
Nan Ya PCB Reports Slight Growth
in August Revenue E
Nan Ya Printed Circuit Board Corp. (Nan Ya
PCB), a manufacturer of single-sided PCBs,
HDI PCBs, and rigid-flex PCBs based in Tai-
wan, has posted unaudited sales of NT$3.37
billion ($105.52 million at $1=NT$31.97) for
August 2023, up by 1.2% from the previous
month, but down by 41.4% year-on-year.
IDTechEx Asks Where Flexible Hybrid
Electronics Add the Most Value E
Can digital and/or high throughput manu-
facturing be applied to circuit boards? Can
stretchable electronics be produced without
sacrificing processing capabilities? Flexible
hybrid electronics (FHE) is an emerging man-
ufacturing methodology that aims to resolve
both of these questions.
Rigid-flex Design Guidelines E
Rigid-flex boards use the same materials as any
rigid board. One way to do this is by creating
the flex portion along with the layers of the
rigid board, and use a delamination process to
remove any unwanted layers. No components
are mounted on the flex portion of the board.
One layer is used for the return and the other
layer is used for your signals. e return is
commonly a GND plane and hatched in the
flex area of the board. Vias are not usually
placed in this area either but may be used if
needed.
Flexible Thinking: Unlocking the Key
to Rigid-flex Design Success E
Despite what some seem to believe, rigid-flex
circuits are not a new technology. In fact, they
are more than a half-century old. At the time
of the invention, my friend omas Sterns was
working at Sanders Associates, the pioneering
flex circuit manufacturer. Like many products
in the first decades of printed circuit technol-
ogy, they were working on a military applica-
tion. e objective was to provide a reliable
method for reducing the size, bulk, weight,
and questionable reliability of wire harness
assemblies while simultaneously reducing
cost and assuring that human error might be
minimized.
Rigid-flex Stackup:
It's a 3D World E
e rigid-flex structure carries a lot of advan-
tages—reliability, dynamic flexure, and the
ability to get things done in tight spaces. But
there's the additional burden of needing to
manage a mechanical world that has additional
