Hooking up a white led strip with the Arduino Uno

Here’s a super simple tutorial to help you hook up a white LED strip to your Arduino Uno.

Shopping List

• 1 Arduino Uno
• 1 Adafruit LED light strip
• 1 250 ohm resistor
• 3 odd pieces of hookup wire (I made my own with a reel of solid core hook up wire)
• 1 12 volt power supply to drive the light strip
• 1 MOSFET (I used an IRLB8721 model), use something that can handle up 16 amps of continuous current so you don’t blow out the light strip)
• 1 USB cable (to program the Arduino)
• 1 Breadboard to wire it all together

Setup

Hooking up the Breadboard & MOSFET

1. Place the MOSFET on the breadboard so you have access to pins 1/2/3. If your looking at it from the front (flat back away from you) the first pin on the right is GROUND, we’ll call GROUND pin 1.
2. Next place a hook up wire between the GND rail on the breadboard to pin 1 of the MOSFET.
3. Next place your 250 ohm resistor between the GND rail on the breadboard and pin 3 of the MOSFET.

Hooking up the Arduino

1. Next hook up GND on the Arduino to the GND rail on your breadboard.
2. Now hook up digital pin 5 on the Arduino to pin 3 of the MOSFET, just in front of the 250 ohm resistor. You want the resistor controlling the signal going to that 3rd pin of the MOSFET, so we get a steady signal.

Hooking up the LED Strip

On the LED strip you should have two wires off it, as it’s simply a white led strip. RED = power, BLACK = ground.

1. Hook up the red wire on the strip to the Arduino’s VIN port, this will allow us to send 12 volts of power to the strip, 5 volts won’t be enough unfortunately.
2. Hook up the black wire on the strip to the middle pin of the MOSFET.

You should be ready to go, here’s some photos to help

Coding

With the Arduino using digital pin 5 let’s program the Arduino, connect it to your computer and flash this code:

// which digital pin we're going to use
#define PIN 5
// how fast you want it to cycle, higher is slower
#define FADESPEED 7
 
void setup() {
  pinMode(PIN, OUTPUT);
}
 
 
void loop() {
  int i;
 
  // fade from low to high (note we can't go to 256)
  for (i = 0; i < 255; i++) { 
    analogWrite(PIN, i);
    delay(FADESPEED);
  }
// then high to low
  for (i = 255; i > 0; i--) { 
    analogWrite(PIN, i);
    delay(FADESPEED);
  }
// pause in between
  delay(50);
}

With that done plug your Arduino into a 12 volt power supply and you should see the light strip cycle

Let me know how it goes,

Enjoy,