Using Arduino Uno to connect 8 LED strips

Other Hardware LEDs and Multiplexing
1

Hey everyone,

I'm a university senior student working on an installation that involves taking 8 LED strips and controlling each strip using an Arduino Uno by turning them off/on, flickering, or changing colors.

I have done a few projects from the Arduino starter kit book and I don't have much knowledge about controlling LED strips, just LED pins. I have done so much research and I know there are 2 types of LED strips (the SMD5050 12v 60 led/meter and the WS2812B 5v) but I don't know which one is more easier to use. I know that if I want to use the 12v LED strip, I have to use 3 mosfets and a 12v power supply. If I want to use the 5v LED strip, I have to use a certain capacitor and a 5v power supply.

While I was researching, I found out new terms such as LED driver and PMW and I don't really understand what they mean?

Also, which type of LED strip should I use? and is there a way to have multiple strips connected to one arduino uno?

Would it be easier for me to connect them using wifi by using the ESP8266 chip or the SparkFun WiFi Shield - ESP8266?

Sorry for asking so many questions, but I really do need some help.

2

While I was researching, I found out new terms such as LED driver and PMW and I don't really understand what they mean?

http://www.thebox.myzen.co.uk/Tutorial/PWM.html
Driver means the circuit between the LED and Arduino output pin that amplifies the voltage and / or current of the output pin to match the LED's requirement.

which type of LED strip should I use?

Depends on exactly what you want to do:-

turning them off/on, flickering, or changing colors.

Is a bit of a hand waving explanation.

I know there are 2 types of LED strips

If only this were true, their are lots of different types. The main divider is do you want to change the colours and state of each LED individually or do you want the strip to show all the same colour / brightness at the same time?

3

If I were you, I'd go with WS2812B strips and use a library like the FastLED library or the Neopixel library from Adafruit.com.
You'll need a hefty 5V supply - each WS2812B needs up to 60mA when at full white (all three LEDs on full). Do not try to power them from an Arduino 5V pin. Do connect the power supply ground to the Arduino Gnd.

For example, here's the start of a sketch where I had 4 strips of 43 LEDs, pretty easy to define.
You could have 12 strips of TBD LEDs, just change the definitions

// ArrayOfLedArrays - see https://github.com/FastLED/FastLED/wiki/Multiple-Controller-Examples for more info on
// using multiple controllers.  In this example, we're going to set up four NEOPIXEL strips on four
// different pins, each strip getting its own CRGB array to be played with, only this time they're going
// to be all parts of an array of arrays.

// changed to 4 strips of 43
// added 6 button inputs
// added timers & flash counts
// add different brightness levels

#include "FastLED.h"

#define NUM_STRIPS 4
#define NUM_LEDS_PER_STRIP 43
CRGB leds[NUM_STRIPS][NUM_LEDS_PER_STRIP];

and

void setup() {
  // tell FastLED there's 43 NEOPIXEL leds on pin 9
  FastLED.addLeds<NEOPIXEL, 9>(leds[0], NUM_LEDS_PER_STRIP);

  // tell FastLED there's 43 NEOPIXEL leds on pin 10
  FastLED.addLeds<NEOPIXEL, 10>(leds[1], NUM_LEDS_PER_STRIP);

  // tell FastLED there's 43 NEOPIXEL leds on pin 11
  FastLED.addLeds<NEOPIXEL, 11>(leds[2], NUM_LEDS_PER_STRIP);

  // tell FastLED there's 43 NEOPIXEL leds on pin 12
  FastLED.addLeds<NEOPIXEL, 12>(leds[3], NUM_LEDS_PER_STRIP);
4

Thanks for your help everyone :slight_smile: