0

I need to make a custom individually addressed LED strip. I could not find what I want anywhere (size and LEDs density are essential factors) - so I thought that it's best to make it from scratch. Before I start I want to make a prototype. It so happens that I had a couple of WS2812b LEDs laying around - just have to chain them and I'm good to go. That's where my problem begins. I am able to make LED RGB PHAT (like this one: https://cdn-shop.adafruit.com/1200x900/3181-00.jpg) dance as I please, but I cannot seem to make contact even with a single WS2812b when it is standalone.

I am connecting a single WS2812b to RPi like this: GND to any ground (duh) VCC to 3,3V (also tried with 5v out of desperation) DIN to GPIO18 I am not touching DOUT

PHAT works like a charm with both rpi-ws281x and Unicorn packages.

Such pinout works for PHAT, should work for any IC RGB strip, why it does not work with a single IC LED? What am I missing?

EDIT:

Okay, so it turned out that I was a doofus and 5 LEDs I tried were broken out of the box. 6th one I took worked like a charm:

https://youtu.be/7rcRC0_exUY

(top class soldering and wiring, I know. Not my proudest moment.)

Also, Craig down there speaks the truth, just not in my case though.

0

WS2812 require 5 volt signals for the data in addition to 5V for power. The Raspberry Pi GPIO are 3.3V.

The HAT you link to includes a 3.3V to 5V level shifter on the board.

Adafruit's tutorial has details about using a level shifter with WS2812 LEDs: https://learn.adafruit.com/neopixels-on-raspberry-pi/wiring

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.