Grounding ws281x LEDs with DGND

Hi all,

I’m working on setting up a BBB to drive some LEDs. I’m using ws281x LEDs, which require 12V+ and 5V data signals. I have a separate level converter circuit which steps up the data outputs from 3.3V to 5V. However, I am getting no illumination when I ground the LEDs with the BBB’s DGND.

Interestingly, my multimeter shows no potential drop between the external supply’s 12V+ and DGND (yes the external supply is turned on :wink: ), even when measured with the external level converter circuit completely detached.

I’m a little stumped here. Shouldn’t 12V+ from my supply to DGND on the BBB measure about 12V? I have the BBB powered from the barrel connector. I feel like I might be missing something simple…

Is your 12V GND connected to the BBB DGND?