Multi-board Etching: Managing Rigid-Flex Designs and Conductivity
April 1, 2020 | Hemant Shah, Cadence Design SystemsEstimated reading time: 1 minute

When I was a very young boy, my dad would delight and tease me by flexing his muscles. He did this with a very special flourish. Rather than simply flexing, he would put his thumb in his mouth, blow, and flex, which gave the appearance that huffing and puffing on his thumb made his bicep pop out. This was a great show for a little boy.
In PCB design, we work with a different type of flex. Advances in consumer and industrial electronic devices have allowed manufacturers to produce smaller devices that have more functionality.
Those devices use rigid-flex designs that provide the form factors needed for portability and—many times—include multiple interconnected boards. With all the interconnections between the boards, PCB designers pay equal attention to signal paths and to the electrical connectivity between boards. On the mechanical design side of things, each board must fit within an enclosure that meets the product specifications. As a result, every multi-board design combines electronic design automation (EDA) with mechanical engineering design (MCAD).
The Sum Is Greater Than the Whole
Good troubleshooting techniques involve considering a system as individual parts rather than as a whole. The same techniques apply to your work with multi-board PCB designs. Each board consists of a single unit that has its own lifecycle.
Some product designs may use a single PCB design for multiple functions or for multiple devices. Others may interconnect multiple PCB designs to produce a complete, fully functional system. Depending on the product design, a single PCB design may have multiple uses. No matter the method, the multi-design represents an overall approach to system design.
To read this entire article, which appeared in the February 2020 issue of Design007 Magazine, click here.
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