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Dotstar strip not working with 5V 2A external power supply
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Dotstar strip not working with 5V 2A external power supply

by kgrove on Tue Jun 15, 2021 10:40 pm

Hi,

I bought a 1m long strip of Dotstar (60 LEDs/m) and I've tried almost everything, and the only success I'm getting is with the 5V pinout on my Grand Central. I don't know what is going on, but I've made 2 strips with 10 Dotstar LEDs and the 5V pinout is the only thing that works flawlessly with each. I'm using the 5V pinout for something else for this project, and having these all hooked up to the same 5V pinout will not work.

I'm kind of at a loss right now, any suggestions are much appreciated. Thanks!

Kevin

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Re: Dotstar strip not working with 5V 2A external power supp

by adafruit_support_bill on Wed Jun 16, 2021 5:23 am

Please post some photos showing all your connections for the strip, processor and power supply.

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Re: Dotstar strip not working with 5V 2A external power supp

by kgrove on Wed Jun 16, 2021 10:20 am

The photo with the consistent color is when I plug it directly into the 5V & GND pinouts. You can't tell from the external power supply photo, but the lights are constantly switching into random colors. I don't get it, but then again, I'm not an electrical engineer...
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Re: Dotstar strip not working with 5V 2A external power supp

by adafruit_support_bill on Wed Jun 16, 2021 3:22 pm

You need a ground connection from the Arduino to the DotStars. All signals are measured relative to GND, so without a ground connection, the signals that control the DotStars are 'undefined'.

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Re: Dotstar strip not working with 5V 2A external power supp

by kgrove on Wed Jun 16, 2021 4:36 pm

I tried hooking it up like the diagram from the lesson

https://learn.adafruit.com/assets/63279
Image

But it didn't do anything other than freeze up the Grand Central, ceasing all functionality.

In the photos, the green wire is going straight to a GC gnd pinout, the black is going to the Dotstar GND and red is going to VCC. CI and DI are connected properly.
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Re: Dotstar strip not working with 5V 2A external power supp

by kgrove on Wed Jun 16, 2021 5:12 pm

I'm just now seeing that I should probably have bought the Neopixel strip, rather than the Dotstar.

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Re: Dotstar strip not working with 5V 2A external power supp

by kgrove on Wed Jun 16, 2021 5:21 pm

Now my GC isn't working at all...

I connect it via USB and it pops up and then immediately disappears

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Re: Dotstar strip not working with 5V 2A external power supp

by kgrove on Wed Jun 16, 2021 6:42 pm

Update: I was able to reset the board. Everything working as normal, except the LEDs. Not gonna try that diagram again

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Re: Dotstar strip not working with 5V 2A external power supp

by adafruit_support_bill on Thu Jun 17, 2021 6:31 am

Power connections for Neopixels and Dotstars are the same. You need a ground connection between the strip and the processor for a signal reference. The diagram is correct. There must be some other issue with your wiring.

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