Getting started with LED Strip (WS2812B)

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1

Hi,

I’m having some issues setting up a 1m 60-LED strip WS2812B. I downloaded the library and uploaded the code to my Arduino Mega with no problems. I then connected the LED strip to PIN 12, Ground and 5V on the Arduino. Upon connecting and providing power, I noticed a few random LEDs blinking for a split second, then everything went dark and nothing else happened. The same random blink happened whenever I plugged the strip to Arduino’s 5V.

Thinking the problem must have been powering it from the Arduino, I then tried to power the strip using a 5V 5A external power supply and got the same result - a few random lights blink when power is connected, but all lights remain off after that. I measured the voltage with a multimeter and was getting 5V, so voltage was not the issue. I also tried to run it form an Arduino Uno instead of the Mega in case the Arduino was defective but the exact same thing happened.

So, far, I’ve only been able to get those few lights to blink when power is provided but nothing other than that. Any other testing/troubleshooting ideas or suggestions?

Thanks,

Felipe.

2

Hello, Felipe.

I am sorry you are having problems with your LED strip. As you suspected, powering the LED strip from the Arduino is not a good idea. The 1m 60-LED strip can draw up to 3A, which is well beyond what the 5V pin on the Arduino can supply. When powering the LED strip using an external power supply, did you have a common ground between the Arduino and power supply? Did you add the recommended capacitor mentioned on the strip’s product page between the ground and power lines?

- Jeremy

3

It’s using the 96LED/M WS2812B LEDs and is driven by an Arduino Leonardo. Since the LEDstrips run on 5V, and the Arduino can’t handle the current drawn from the LEDs, i bought a 5V10A switching power supply to power them. This PSU gives an output of 5V and can handle up to 20 Amps current, which is more than enough, but remember: the ‘bigger’ the PSU, the cooler it will stay. I’ve seen people use an old USB hub or cellphone power supply, but this all depends on the amount of LEDs.