Portable Neopixel Power distribution

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Ollec
 
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Joined: Wed Nov 14, 2012 9:11 pm

Portable Neopixel Power distribution

Post by Ollec »

Hello Adafrut!

I am working on adding a 2.25m string 'Adafruit NeoPixel Digital RGB LED Strip - White 30 LED' connected to a Flora on a jacket. I am wondering about the methods of distributing the power to the pixels. Specifically if the power draw is too much for the battery back.

Current setup:

~6000 mAH liPoly battery
USB/DC Lithium Polymer battery charger 5-12V - 3.7/4.2v cells
Flora
~65 NeoPixles

I figure the max Amp draw will be around 5 Amps which is cutting it close to the max 1C for the battery. The obvious solution is to not have all the LEDs on at the same time and just avoid the problem. However I would like to actually address the problem. If I were to add a second LiPoly battery and charger how would you suggest connecting it? Also is this a recommend solution?

If a second battery what do you think If I make the ground for the two batteries and Flora all the same and then divide the NeoPixles between the two batteries and have one data line for the whole set? I know it is a bad idea to connect LiPolys in serial or parallel so I figured connecting them to different set of LEDs may be a safe option.

Thank you kindly,
Ted

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adafruit_support_bill
 
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Joined: Sat Feb 07, 2009 10:11 am

Re: Portable Neopixel Power distribution

Post by adafruit_support_bill »

The theoretical worst case for 65 pixels is 3.9A That is well within the capabilities of the battery. And that is a very conservative estimate. Most projects use only a fraction theoretical max on average.

It is a good idea to feed from multiple points to minimize voltage drop. See this guide for powering tips.
http://learn.adafruit.com/adafruit-neop ... -practices

Ollec
 
Posts: 2
Joined: Wed Nov 14, 2012 9:11 pm

Re: Portable Neopixel Power distribution

Post by Ollec »

Hello A_S_Bill,

Thank you for the prompt reply. I am glad to hear you don't think it will be an issue. For the time being I will continue forward with only using one battery. However if I do end up wanting to use multiple batteries, How would one go about it? Was I going down a functional path?

Thank you again,
Ted

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adafruit_support_bill
 
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Joined: Sat Feb 07, 2009 10:11 am

Re: Portable Neopixel Power distribution

Post by adafruit_support_bill »

When powering from two batteries, just cut the 5v trace between the two halves of the strip. Leave the signal and ground wires connected.

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