Datasheet

Be extremely cautious with bench power supplies.

Some — even reputable, well-regarded brands — can

produce a large voltage spike when initially switched

on, instantly destroying your NeoPixels!

If you use a bench supply, do not connect NeoPixels

directly. Turn on the power supply first, let the voltage

stabilize,

then

connect the pixels (GND first).

Estimating Power Requirements

Each individual NeoPixel draws up to 60 milliamps at maximum brightness white (red + green + blue). In actual use

though, it’s rare for all pixels to be turned on that way. When mixing colors and displaying animations, the current draw

will be much less. It’s impossible to estimate a single number for all circumstances, but we’ve been using 1/3 this (20

mA per pixel) as a gross rule of thumb with no ill effects. But if you know for a fact that you need every pixel on at

maximum brightness, use the full 60 mA figure.

To estimate power supply needs, multiply the number of pixels by 20, then divide the result by 1,000 for the “rule of

thumb” power supply rating in Amps. Or use 60 (instead of 20) if you want to guarantee an absolute margin of safety

for all situations. For example:

60 NeoPixels × 20 mA ÷ 1,000 = 1.2 Amps minimum

60 NeoPixels × 60 mA ÷ 1,000 = 3.6 Amps minimum

The choice of “overhead” in your power supply is up to you. Maximum safety and reliability are achieved with a more

generously-sized power supply, and this is what we recommend. Most power supplies can briefly push a little extra

current for short periods. Many contain a thermal fuse and will simply shut down if overworked. So they may

technically

work,

but this is the electronics equivalent of abusing a rental car.

Keep in mind, 60 mA is a

worst case

estimate! We’ve written a whole separate tutorial on getting things under

control: Sipping Power with NeoPixels.

I estimate I need a 3.6 Amp power supply. I have a 10 Amp supply on-hand. Will this cause my NeoPixels to

explode?

As long as the output is 5 Volts DC, you’re golden. The LEDs will only draw as much current (Amperes) as they

need. So extra Amps are OK — in fact, it can be a

good

thing. The larger power supply will run cooler because it’s

not being pushed to its limit.

Excessive

voltage,

however, will definitely kill your LEDs.

Extra Amps = good. Extra Volts = bad.

What about batteries and “Amp hours”?

Amp-hours are current over time. A 2,600 mAh (milliamp-hour) battery can be thought of as delivering 2.6 Amps