This week’s EYE ON NPI is super spacey – it’s Wurth Elektronik SMD Spacers, a variety of pick-and-place-able hardware components that solder directly to your PCB designs during in a standard SMT line, and speed up your assembly and simplify your mechanical design.

The first thing you’ll learn as an engineer is that not only do you need to worry about your schematic being correct, and the layout being manufacturable and optimal for signal and power integrity, but you also have to make sure it fits into whatever enclosure the mechanical engineer cooked up. Worse, sometimes that mechanical engineer is you! For example, a common design requirement is to have a front panel, and then you have to mount the PCB against it with standoffs or spacers, so that the buttons, knobs and switches are accessible but protected. We used this technique with the first Adafruit product x0xb0x – in this case we used hex standoffs.

These come in a vast array of configurations, lengths and threads. There’s female-female, female/male and even unthreaded ones. By mixing and matching, plus adding machine screws and lock washers you can construct any sandwich of PCBs.

Standoffs work great, but they add a lot of time to the assembly process: they have to be manually lined up with the PCB holes, they need lock washers to keep them from rotating in place, and they can fall into the enclosure during assembly or repair. Being metal that means shorting against all your nice PCBA components!

That’s why we’re big fans of SMT solder-able standoffs. We’ve used them in our designs like the Adafruit Macropad and Memento camera. We love that they come on pick and place reel, with pickup tabs, and solder nicely in place using a standard SMT processing method. They always have the same uniform height, same location, and will not twist when attaching the machine screws on the other side.

The Wurth Elektronik SMD spacers are available in a huge variety of configurations. For the threaded type: lengths from 1mm to 15mm and M2, M2.5 or M3 thread. For unthreaded spacers, hole diameters of 2.25mm, 2.7mm or 3.3mm.

They also have male-thread spacers, and the REDCUBE WP-SMRA series right-angle spacers which are brilliant and should allow for full-sided enclosures without wrangling. Which we’ve never seen before!

If you want to try the full range, pick up a SMT Spacer Design Kit. All are available on tape and reel / cut-tape and are in stock at DigiKey for immediate shipment. Order today and you can start integrating these stand-offs into your next PCB design.

See the parts on DigiKey.

Video and manufacturer’s video: