Neopixels & micro:bit

Question

Hi all,

I want to use NeoPixel and micro:bit together. But NeoPixels is required 5V and micro:bit provides 3V. Do I damage the micro:bit if i use them together? I use a regulator to convert 5V and it works properly, but I'm wondering if is there any easy to use module/accessory for Microbit to use it with Neopixel, ultrasonic sensor?

Neopixel Ring: https://www.adafruit.com/product/1586

Sorry for my english, im not good in english,

Thanks

tonydbeck · Accepted Answer

Hi Hilal,

According to the Adafruit website, the LED's used in the Neopixel rings are the SK6812 type. On page 4 of the data sheet it shows that the VDD supply voltage should be 5.2V. It does not seem to specify values for the min or max VDD.

However there is a tutorial on Adafruit that shows a Neopixel operating fine when connected directly to the BBC micro:bit. There is a warning though that you should not set the 24 pixels to more than 50% as the micro:bit will not be able to provide enough current.

On this basis, you will not need any module or accessory unless you want to drive the pixels to a high brightness.

Of course, you could use a seperate 5V supply for the Neopixel ring - something I have used before is a portable phone USB charger. One thing you have to watch for though is that the data signal is not less than 70% of the VDD voltage. So if supplied at 5V, the data signal should be minimum 3.5V. You can use a level shifter to help with this. Or you could follow this cheat on HACKADAY:

https://hackaday.com/2017/01/20/cheating-at-5v-ws2812-control-to-use-a-3-3v-data-line/

There is also some other really good info on Adafruit:

https://learn.adafruit.com/adafruit-neopixel-uberguide/powering-neopixels

Hope this helps!

-----------------------------------------------------------------

Tony

stevesmythe · Answer

You should be safe if there are no more than eight neopixels lit at the same time or, as Tony says, you keep the brightness down. I have not had a problem. You might find, if you are powering the micro:bit and neopixels from a USB socket, that effects like rainbows do not display correctly. I have never damaged a micro:bit if I follow the above guidelines.

hilalgungor · Answer

Thank you so much for quick reply and all the explanations!

rhubarbdog · Answer

Neopixels work best with 5 volts on the power pin, but will happily work with a 3 volt microbiology pin powering the data line. Just remember to connect ground on the microbit to ground on the 5 volt supply

Neopixels & micro:bit

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