Rigid-flex Electronic Circuit Board Design Eliminates Healthcare Wearables Obstacles
The majority of electronic circuit boards in today’s times are merely rigid plates to connect circuitry. However, that’s changing rapidly; the interest in flexible circuit boards (or flexible circuits) is rapidly raising mostly as a consequence of the engaging wearable product market. Possibly the largest segment of that market is the medical care industry where wearable devices will be helpful to gather all kinds of physical details for examination and study, and also individual health use. Presently wearables are offered to track beats per minute, blood pressure levels, glucose, ECG, muscle movement, and a lot more.
The wearable devices bring quite a few issues for circuit board designers that rigid boards do not. Listed below are some of such problems along with what designers are able to do to help remedy them.
3 Dimensional Design
While every PCB is actually 3 dimensional, flexible circuits permit the entire assy to be bent and folded to adapt to the package that the merchandise takes up. The flexible circuitry is folded in order that the rigid electronic circuit boards fit into the item package, taking up room.
There’s a lot more to the design, so the increased challenges, than merely connecting the rigid boards. Bends need to be perfectly designed so boards fall into 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 simulate the printed circuit board assy. At this point, design tools are obtainable that come with 3D modelling of the rigid-flex assembly, making it possible for easier design and much greater precision.
Small Products and Dense Circuits
By definition, wearable goods are required to be small and highly discreet. Before, a medical “wearable” just like a Holter heartrate monitor integrated a pretty big exterior device with a neck strap or maybe belt mount. The recent wearables are tiny and attach straight away to the sufferer without any or few external wires. They pick up various data and are able to even process a few analyses.
An unobtrusive device mounting straight to the patient demands flexible circuitry and intensely compressed layouts. Moreover, the board shapes tend to be spherical or even more uncommon shapes, requiring creative placement and routing. For this kind of tiny and densely-packed boards, a PC board tool that is improved for rigid-flex designs helps make addressing strange shapes a lot easier.
Stackup Design is very important
The stackup – the map of the circuit board layers – is extremely important when working with 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 assy. As said before, the layout of the bending area ought to be designed to help ease the pressures on the traces and pads.
One of the greatest troubles with rigid-flex designs is qualifying multiple producers. After the design is accomplished, all aspects of the design should be communicated to the board fabricator in order that it will be effectively manufactured. However, the best practice is to find one or more makers at the beginning of the design and team up with them to ensure that your design meets their production specifications as the design moves forward. Working together with manufacturers is made simple by using standards. In such cases, IPC-2223 is the vehicle for communicating with your fabricators.
The moment the design is completed, the data package must be assembled to hand-off to be made. Whilst Gerber still is employed for standard PCBs in some companies, in terms of the challenges of rigid-flex, it is highly recommended by both PCB software program providers along with manufacturers that a more intelligent data exchange format be utilized. The two most well-known intelligent formats are ODG++ (version 7 or higner) and IPC-2581, as both versions precisely designate layer specifications.