Datasheet
Amps. Some minor modifications are needed…Google around for “ATX power supply hack.” Note that the ATX 5V rail
can be very unstable if there's no load on the 12V rail!
Even larger (and scarier, and much more expensive) are laboratory power supplies with ratings into the
hundreds
of
Amps. Sometimes this is what’s needed for architectural scale projects and large stage productions. And occasionally
we get requests for help…
Please note that projects of this scale are potentially very dangerous, and the problems of power distribution are
fundamentally different than hobby-scale projects. As much as we enjoy helping our customers in the forums, they are
for
product technical support
and not full-on
engineering services.
If you’re developing a project of this scope, hire a
professional electrician with experience in high-power, low-voltage systems such as photovoltaics or large RVs and
boats. This is no charade.
Distributing Power
The longer a wire is, the more resistance it has. The more resistance, the more voltage drops along its length. If voltage
drops too far, the color of NeoPixels can be affected.
Consider a full 4 meter reel of NeoPixels. With 5V applied at one end of the strip, for those pixels closest to this end,
power traverses only a few inches of copper. But at the far end of the strip, power traverses
8 meters
of copper — 4
meters out on the +5V line, 4 meters back on the ground line. Those furthest pixels will be tinted brown due to the
voltage drop (blue and green LEDs require higher voltage than red).
Pro Tip: NeoPixels don’t care what end they receive power from. Though data moves in only one direction, electricity
can go
either way.
You can connect power at the head, the tail, in the middle, or ideally distribute it to several points.
For best color consistency, aim for 1 meter or less distance from any pixel to a power connection. With larger NeoPixel
setups, think of power distribution as branches of a tree rather than one continuous line.
© Adafruit Industries https://learn.adafruit.com/adafruit-neopixel-uberguide Page 21 of 100