# How to work with WS2812B 16x16 matrix panel from aliexpress

I'm completely new to Arduino, and I want to build the project using an LED 16x16 matrix, but I don't know where to start. On the internet, I keep finding these custom matrix panels and they aren't similar to mine. So I'm asking here. Does anyone have experience with this Arduino-compatible RGB LED matrix panel? This is the link to the Aliexpress product. Will I need an additional power supply? What will I need to install to make it work? Where do i plug what wire into my arduino? Thanks for any answer!

## 1 Answer

It's just a string of WS2812B LEDs that have been "bent" into a grid. You treat it exactly like any other WS2812B strip of LEDs.

You have 256 LEDs, and as far as the Arduino is concerned, they are just in a line numbered 0-255.

The "grid" arrangement is solely down to you to you to calculate. Fortunately 256, or 16x16, is very easy to work with: you have a byte which can represent any one of the LEDs, and each half of the byte (a nibble) is one coordinate.

The traditional calculation to convert X and Y into a linear number is:

``````num = x + y * width
``````

where `width` is the number of LEDs in the X direction (16). However since we're working with a width of 16 that can be optimized to use bit-shifting and bitwise operations:

``````num = x | (y << 4)
``````

That is assuming LED 0 is on the left (either top or bottom) and LED 1 is one place to the right.

Will you need an external power supply for it? Yes, most certainly (and they even provide you with a dedicated power connection for it). 256 LEDs, if all are turned on full brightness at once, could consume up to about 15 amps (20mA per channel, three channels per LED, 256 LEDs).

• Just want to add more to your answer. Theoretically, 5V - 15A the power supply he needs. But he may get away with just 2A power supply if he's careful not to turn on all LEDs at a time and just use about 80/255 brightness on each colour. From my experience, I had a project that used 18 panels of 8x8 ws2812b. It was just a single letter (using just one colour) displayed on each LED panel so that I could get away just with a single 12V - 2A power supply for the whole system. Step down (buck) to about 3V3 at each LED panel and each panel had its own nano clone to control it. Apr 5, 2021 at 15:04