Skip to main content
Arduino

You are not logged in. Your edit will be placed in a queue until it is peer reviewed.

We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.

Required fields*

9
  • The resistor is on a signal line. There should hardly be any current there. I don't thing it's anything to do with that resistor. Have you tried powering the trinket from the same 5V brick, instead of USB? I think it might be a eathing problem. The bench power supply is mains earth referenced, while the brick is probably floating. Are you also really sure the grounds are connected? Maybe there's a loose breadboard connection. Commented Dec 31, 2020 at 17:41
  • 1
    WS2811 expected a minimum of 0.7xVdd for a logic high signal, which is 3.5V. You're marginal at best even if everything is grounded properly. You should level-shift that signal. (And indeed that LED isn't a dropping resistor - your Trinket would have blown up long ago if you tried to feed 1.5A through one of its pins.) Commented Dec 31, 2020 at 17:50
  • Yeah I moved everything to the wall adapter and I double checked the ground connection and it's good, but still have the issue. I'm adding a new pic in of the circuit. Commented Dec 31, 2020 at 17:53
  • @Mat how would i do that level shift? Is this a case where I'd need to add a transistor to provide a higher voltage signal (e.g. pull the 3.3 from the trinket's top right pin) and then control the transistor with my signal pin? Ah wait, I forgot it can't be the 3.3v pin b/c we'd need 3.5, so maybe a voltage divider coming off the 5v power? Commented Dec 31, 2020 at 17:56
  • go back to the two power supply setup ... remove the ground connection between the two power supplies ... connect a ground wire directly from the trinket to the LED strip Commented Dec 31, 2020 at 18:19