NeoPixel WS2812B Doesn't Light Up (Raspberry Pi)

[cfm21]

Hello all,

I am very new to the hobby electronics scene but I decided to dive in to complete a passion project of mine. I am trying to drive around 35 WS2812B LEDs purchased from this link. I am powering them with an external power supply, and have grounded them to the RPi (3 B v1.2) as well as connected Din to GP18. I am using this sample code found on the website:

Code: Select all

import board
import neopixel
pixels = neopixel.NeoPixel(board.D18, 9)
pixels[0] = (255, 0, 0)

Currently, I have 9 LEDs wired up and I am trying to test them before I move any further. Here is a list of things I have tested:
Continuity trough the 5v and ground lines from the 1st LED to the last
Using different PWM GPIO pins
Checking voltage on GPIO 18 when the script was run (no voltage indicated)

I'm running out of things to try. Please share any insight you have

[cfm21]

There appears to be continuity between the data line and the 5v line. Could this be causing the problem?

EDIT: This continuity seems to stop when the unit is unplugged from the power supply. In addition, the processor on the RPi was extremely hot when this was occuring. I hope I didnt fry something, but I double checked and I was definitely grounded and connected to GPIO 18.

[cfm21]

Upon further investigation, it seems I have fried the Pi with a solder bridge between 5v and Din on one of the lights. An expensive mistake, so if anyone knows where to get another Pi without paying scalper prices, please let me know

[Franklin97355]

Can you post a picture of the offending pixel and the component of the pi that is affected?

[cfm21]

Can you post a picture of the offending pixel and the component of the pi that is affected?

The component affected is the processor. There’s no visible damage, but as soon as it’s connected to the power supply, it quickly overheats (above 80 C) and the Pi fails to boot.