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I have an AtTiny85 and a series of 144 5v Adafruit NeoPixels. I'm following something similar to this tutorial: http://shin-ajaran.blogspot.com/2014_04_01_archive.html, but it doesn't mention if the current draw will damage the AtTiny85. I suspect it will. How would I wire this with a 5v 5a power adapter? I want to make the profile as small a possible, so the AtTiny seems the best route. I don't have much experience with Arduino projects larger than 5v, so any help is greatly appreciated.

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The Adafruit NeoPixels already provides a solution for your problem.

Don't try to run all the power through your AtTiny85.

enter image description here

Send the 5 volts to your AtTiny85, but branch off the 5 volts before the AtTiny85 and send the power to the VCC (pin3) and VDD (pin5).

EDIT : If you are placing the NeoPixels a long distance from your AtTiny, you could run a separate wire (VCC for controls) alongside the power wire (VDD for LED power). This way you will have a full 5 volts for the controls circuit, not messed up or glitched by power fluctuations by the higher power LED circuit.

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  • \$\begingroup\$ Thank you for your response. I was already planning on doing the AtTiny85 and NeoPixel strip in parallel with an appropriate capacitor in between. I should clarify a bit more. What I'm worried about is how the current will view the circuit. Will it spend most of the current in the NeoPixels or will it consider the AtTiny the path of least resistance and flood there. It might be a silly question, but I have limited experience with circuits. \$\endgroup\$
    – Brittany Mcgarr
    Commented Dec 16, 2015 at 19:46
  • \$\begingroup\$ Bring your NeoPixel return lead for ground (VSS Ground) back to your power supply, not to the AtTiny. Also use a larger ground wire so that voltage drop in ground lead remains low. Then be sure to keep your AtTiny ground lead to power supply very short. Would have been good if NeoPixel offered separate ground for the controls circuit. \$\endgroup\$
    – Marla
    Commented Dec 16, 2015 at 19:51
  • \$\begingroup\$ Alright. Sounds like the configuration I have should be safe then? Thank you for the response. \$\endgroup\$
    – Brittany Mcgarr
    Commented Dec 16, 2015 at 19:55

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