Neopixel connection with UNO

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dukeu69
 
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Neopixel connection with UNO

Post by dukeu69 »

I know this may sound dumb, but can anyone tell me what I need to connect A 60 led Neopixel strip to an Arduino UNO and power it.

Thank you!

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adafruit_support_mike
 
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Re: Neopixel connection with UNO

Post by adafruit_support_mike »

Not dumb at all.. our resident blinky guru wrote a whole tutorial on the subject: https://learn.adafruit.com/adafruit-neo ... e/overview

dukeu69
 
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Re: Neopixel connection with UNO

Post by dukeu69 »

Yeah i'm still confused. I need a digital JST connector to be controlled by the arduino and a wall adapter to power. I don't understand why the other end can't be connected to the arduino for power, considering that it the arduino will be powered by a 5v wall adapter.

Please help, Thanks

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adafruit_support_mike
 
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Re: Neopixel connection with UNO

Post by adafruit_support_mike »

NeoPixels use up to 60mA each, so 60 of them will use up to 3.6A.

An Arduino running from USB power is limited to 500mA because that's the most you can send through a standard USB connection. If you use an external power source (plugged into the 2.1mm barrel jack) and take power from the Arduino's 5v pin, you can get up to 1A from a 7v supply.

That's still only a third of what you'd need to run a 60-LED strip full blast, and you have to leave about 100mA for the Arduino itself.

The main reason to use a separate power supply, though, is that NeoPixels are noisy. They control the light levels by turning the LEDs on and off quickly. That has roughly the same effect on the supply power as the person at the next gas pump repeatedly making the nozzle cut out as they try to get that last couple ccs of fuel into the fill pipe.

The microcontroller uses the supply voltage as its reference for deciding what counts as a HIGH signal and what counts as a LOW one. Enough noise in the supply can cause errors that crash the chip and force it to reboot.

dukeu69
 
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Re: Neopixel connection with UNO

Post by dukeu69 »

Yeah i'm planning on hooking these leds to my guitar effects pedal board. So, I will need two power supply's, one for Arduino and one for neopixel, as well as two Jst connectors. Maybe another type of led would be a better investment. I wasn't looking to drop 50 bones just for lights

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