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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.

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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

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