For the Tiny balloon project from @ItsMrJP I designed a 8 LED ring with an outer diameter of only 18mm and 8 addressable WS2812C LEDs. They are much smaller than the normal LED rings based on 5050 LEDs. Inner diameter is 10 mm. The PCB has a thickness of 1mm.
3d files: https://www.printables.com/model/359715-tiny-fiber-optic-balloon2020
The small size allows you to realize tiny projects which are too small for the addressable LED rings which are available on the market.
They a sold as sets of 4 rings. Optional you can buy 4 meters of 1.5mm side-glow optical fiber to build tiny balloons.
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