RGB LED Ring - V1.21

The next round in my prototyping game. I declare this board as the final version, more or less ;-)

The TS2940CW 5V voltage regulator is truly a masterpiece of engineering. It uses a PNP transistor as the output stage and therefore the voltage drop is more or less only based on its V(CE)-sat voltage. The maximum drop is 0.6V at about 1A. This board only needs about 100mA max. and therefore you can safely ignore the regulator's voltage drop. If you feed the board with 4.0V, the cpu will get about 3.95V - very nice! You can use the onboard regulator to feed power to other parts of your project as well.

I'm thinking about adding this one to my collection of purchasable DIY KITs on my blog. But right now I'm out of LEDs and haven't found a cheaper source for them that I like. I haven't used alibaba/aliexpress yet, so I feel a bit uneasy with ordering in the 1k pcs range directly from china. Ebay is not a good source for high volume orders it seems. Still too expensive per single RGB LED.

It reliably runs with 4V to 14V. The voltage regulator could take more, but the tantalum capacitors max out at 16V. Although less energy efficient, it can now be easily used with a 9V block or several AA batteries and doesn't require a somewhat costly boost converter anymore.

Click here here to see the front side.

Design files, code and documentation.