Rigid-flex PCB Board Design Eliminates Wearable Healthcare System Challenges
The majority of electronic circuit boards in the world today are just rigid plates to connect circuitry. Yet, that’s changing fast; the desire for flexible circuit boards (or flexible circuits) is speedily growing mostly as a result of the burgeoning wearable product market. Maybe the largest segment of that market is the medical care industry in which wearable devices will be used to collect all types of physiological records for prognosis and study, and individual health use. Witout a doubt wearables can be obtained to keep an eye on heart beat, blood pressure, glucose, ECG, muscle movement, plus more.
The wearable devices bring a lot of challenges for PC board designers that rigid boards do not. Below are some of these problems and what designers can do to alleviate them.
While every single circuit board is actually 3 dimensional, flexible circuits permit the entire assembly to be bent and folded to conform to the package that the product uses up. The flex circuitry is folded in order that the rigid printed circuit boards easily fit in the item package, living in space.
There is lots more to the design, hence the extra challenges, than simply connecting the rigid boards. Bends must be accurately designed so boards get in line where they’re meant to mount, while not placing force on the connection points. Up until recently, engineers actually used “paper doll” models to imitate the PCB assy. At this moment, design tools are available that come with 3D modelling of the rigid-flex assembly, allowing faster design and far greater accuracy.
Tiny Products and Squeezed Circuitry
Obviously, wearable merchandise ought to be small and inconspicuous. Over the past, a healthcare “wearable” for instance a Holter heartrate monitor contained a fairly large exterior device with a neck strap or belt mount. The innovative wearables are tiny and attach straight to the patient with no or few external wires. They pick up a wide range of records and can even process several analyses.
An unobtrusive device attaching directly to the patient demands flex circuitry and intensely compressed layouts. Also, the board shapes are often circular or even more unconventional shapes, calling for creative placement and routing. For these kinds of small and dense boards, a Electronic Circuit Board tool that is optimized for rigid-flex designs helps make addressing uncommon shapes far simpler.
Stackup Design is a must
The stackup – the map of the PC board layers – is essential if you use rigid-flex techniques. If possible, your PCB design software has the capability to design your stackup including both the rigid and flex parts of the assembly. As said before, the layout of the flexing area needs to be designed to decrease the stresses on the traces and pads.
One of the greatest troubles with rigid-flex designs is qualifying several manufacturers. After the design is done, all aspects of the design must be communicated to the board fabricator so that it will be correctly produced. Yet, the best practice is to find one or more manufacturers at the outset of the design and work together with them to make sure that your design suits their manufacturing needs as the design moves on. Participating with fabricators is simplified by utilizing standards. In such cases, IPC-2223 is the vehicle for getting in touch with your manufacturers.
As soon as the design is finished, the data package must be assembled to hand-off to be manufactured. Whilst Gerber remains to be employed for standard PCBs in certain companies, in terms of the intricacies of rigid-flex, it is highly recommended by both PCB software tool providers and also fabricators that a more intelligent data exchange format be employed. The two most popular intelligent formats are ODG++ (version 7 or higner) and also IPC-2581, as both versions clearly designate layer demands.