Important basic information about powering Pixel LED Strips.
This page contains information about Pixel controller software, making a pixel controller board, an illustrated, the pixel led power supply you need and offers you a free pixel controller circuit diagram pdf
Pixel LEDs generally use either 5 volts or 12 volts to power them. And the amperage they draw, which of course depends on the number of LEDs and the brightness that you choose, can be significant.
Each single 12mm RGB LED pixel can draw up to 60mA from a 5V supply. That means a strand of 25 can use up to 1.5 Amps. That’s a peak rate, which assumes that all the LEDs are on at full brightness. If most of the LEDs are kept dim or off (as when animating patterns), the power usage can be 1/3 this or less.
Your first consideration is choosing your voltage source. It MUST match your LED rating. Touch a 5v ws2812B LED strip with 12 volts and it smokes, smells horribly and burns out the LEDs faster than you can utter an appropriate expletive. So look and think before you apply power or the house boss may have some comments about you stinking up the house.
Your strip will have connecting wires on both ends. You can only power from one end. There will be arrows on the strip that show the proper direction of current flow. The second set of wires is used to connect to another strip. If you are not going to add another strip, insulate the wires with shrink tube or whatever.
As you pass from the power input point down the strip, resistance will cause the voltage to drop. Injecting power, from the same power source, at points down the strip will keep voltage at the required level and your lights will not dim.
To Make A Pixel Controller
Materials Required
Arduino Control Board – We find that a Nano is sufficient for most purposes. You can also use an UNO or Mega.
Strip (Vero) or Perf Board. Because of its design, we find Vero board easier to use.
Capacitor – 1000 uf.
Resistor – 220 to 560 ohms
Pin Headers -Female Dupont and Mechanical pin headers.
Controller Kit
All the parts above are available, along with an instruction booklet here.
Pixel LED Wiring Diagram
This is a graphic illustration of how 5 volt Pixel LEDs are wired.
Note that you do NOT have to connect the Pixel strip to a PWM pin on the arduino. Connection to any data pin is fine.
The data wire needs a resistor of 220 to 560 ohms inserted between the strip and the micro controller.
A 1000 uf capacitor goes across the + and – connections to the led power leads. The capacitor prevents any voltage surges, particularly the one that occurs on startup, from damaging the LED strip.
This wiring is fine if you are going to use only a few of the Pixels. If you use more you should power the strip from an external power supple.
The picture to the left shows a completed DIY Pixel LED controller.
It uses a Nano to which the desired sketch has been added. In the program, the data pin is designated as D6. A wire passes from D6, connects to a resistor and then goes on to a pin header. Four pin headers are on this board so that 4 strips can be used.
A 1,000uf capacitor is wired across the + – power lines.
A fourth pin header connects to the power supply and a fifth to 5 volts to power the nano. The grounds on the 5v to the nano and the pixel power supply, whether it is a 12 volt or 5 volt power supply are connected. On this board, there is a hard wired connection so all that you have to do is plug and play.
Use regulated power supplies. They are those whose voltage does not change with current draw. A converted computer power supply is fine. Batteries also work well.
In the video to the left you can see a controller like this do its part in adding life to a diorama. Not only does it change the light in the sky it cycles the other lights in the diorama over a “diorama 24 hour cycle.”
I hope that this has helped. If you have questions, comments or need help, contact me. Click here.
Once again here is the link to the parts you will need as well as other useful electronics kits.