Defective DotStar strip?

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psychopenguin37
 
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Defective DotStar strip?

Post by psychopenguin37 »

I just ordered two DotStar strips, one 4m and one 1m. The 1m one works fine with the Feather M0, but I haven't been able to get the 4m one to light up at all. I have a feeling it's defective, as I'm hooking it up exactly the same as the 1m one, even hooking up the power leads to a 5v supply that works for all my other, even longer strips.

What should I do? When I try to use the "Contact Us" link at the bottom of the page, it tells me to post in the forums, so that's what I'm doing.

Thanks!

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dastels
 
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Re: Defective DotStar strip?

Post by dastels »

Can you post a clear photo of the strip wiring and especially the wired/input end of the strip. I realize it might not be overly visible with the rubbery cover, but I'm curious about the connections there.

Dave

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psychopenguin37
 
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Re: Defective DotStar strip?

Post by psychopenguin37 »

IMG_0859.jpg
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The red/black wires are switched in my JST connector (see pic), but they're connected correctly with red from the strip going to BAT and black from the strip going to GND

When those dangling red/black wires from the strip are connected to my 5v power supply and I try one strip at a time, one strip works but the other doesn't.

I also noticed that the 5th and 10th LEDs on the strip have an extra black dot on on them. The 5th is visible in the image. These aren't present on the working strip.

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dastels
 
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Re: Defective DotStar strip?

Post by dastels »

You might be better off powering the strip from 3.3v, though that might quickly be too much for the onboard regulator.

As I feared there's no way to see what's going on at the end of the strip.

Anyway, that "extra" black dot... that's inside the dotstar?

Dave

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psychopenguin37
 
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Re: Defective DotStar strip?

Post by psychopenguin37 »

Yup, inside. I thought these were 5v strips... how would 3v be better? Especially for the longer strip and not the shorter one, which works fine on 5v.

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psychopenguin37
 
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Re: Defective DotStar strip?

Post by psychopenguin37 »

So, am I SOL? Do I just have to buy another strip and hope it works?

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adafruit_support_carter
 
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Re: Defective DotStar strip?

Post by adafruit_support_carter »

but they're connected correctly with red from the strip going to BAT and black from the strip going to GND
Are you actually powering the setup with a battery?

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psychopenguin37
 
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Re: Defective DotStar strip?

Post by psychopenguin37 »

I'm not using a battery. I'm using this power supply: https://www.amazon.com/gp/product/B01D8 ... UTF8&psc=1

I was following this tutorial and thought I needed to connect "BAT" to +5v coming from the power supply. Maybe that fried my strip? I think the board's ok since it still works fine with the smaller strip. I have everything taken apart now, but I can try connecting it again and leaving BAT disconnected if you think that might resolve the issue.

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adafruit_support_carter
 
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Re: Defective DotStar strip?

Post by adafruit_support_carter »

That power supply has a lot of current output capability. So accidentally zapping something is a possibility. Try removing the 5V40A supply from the setup. Power the strip directly from the Feather and then just try lighting the first pixel. The Feather should be able to supply enough power for that. That way you can sanity check the current state of the LED strip.

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