I have a simple connection here:

  • A WS2812B 5m 300 leds strip 5V;
  • A Power Supply MS-150-5 150W 5V;
  • Arduino with a simple code to blink 10 first leds;

TEST: If I connect my power supply to my LED with a wireless controller with some saved presets, everything works fine. Colors, red, blue, white ( some voltage downhere ), but ok, working. If take off the wireless controller and connect the LED to the Arduino, GND,+5, DATA, with a simple code, it's ok, 10 leds blinking, working fine. BUT if I connect only the data to Arduino and connect the power to my power supply, now all the stripe go crazy, show no sense colors.

The Arduino code is ok, voltage is ok. Power supply is big enough. Even say to blink only one light is turning on all leds.

I was with a differente power supply before, same but 70w and was working ok. Now with 150w is not working. Why is not working with this one that is bigger? Maybe any noise ?

I'm connecting the power supply directly to the LED and only using the Arduino Data.

  • 3
    So... you don't connect the grounds together? – Majenko Oct 24 '18 at 23:20
  • The Arduino GND and the power supply? No. – Isslerman Oct 25 '18 at 3:51
  • 2
    Well there is your problem, they need a common ground forthe signal to get through correctly. – ratchet freak Oct 25 '18 at 8:47
  • Tks guys. I'm using the USB power for the Arduino and the external power supply for the LED. I'll try to use all the same source power and post here the result. – Isslerman Oct 25 '18 at 14:15
  • the source need not be the same, and usually isn't, the ground (aka common) needs to be, well, common. – dandavis Oct 25 '18 at 16:12

Just make sure the Gnd from the Arduino and power supply are connected together - otherwise it would cause a common issue. Another recommendation would be to include a capacitor, usually a size of 1000uf is recommended.

| improve this answer | |
  • Tks! Now is working like a charme. Was the GND between Arduino and the Strip. – Isslerman Sep 12 '19 at 16:39

Tks for reply guys. Thats correct. I have connected the GND of the external power supply with the GNC of Arduino and everything is fine.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.