A beginner guide to addressable LEDs.

Smart LEDs look amazing, but getting started can feel overwhelming. What controller do you need? How do you calculate power requirements?

This guide walks you through building an 8x32 LED matrix running WLED. WiFi-controlled, 100+ built-in effects, controllable from any phone. No soldering, no coding.

You need three things: LEDs, a controller, and a power supply.

I'm using a BTF-Lighting 8x32 WS2812B matrix - 256 addressable LEDs at 5V.

When shopping, pay attention to LED count and voltage. These determine your other components.

The controller runs the software that drives the LEDs. You can go full DIY with an ESP32 for a couple of euros, but then you're dealing with level shifting, fuses, and flashing firmware yourself.

For beginners: get an Athom WLED Controller. Pre-installed with WLED, proper power handling included.

Your power supply depends on LED count. Each WS2812B draws up to 60mA at full brightness. For 256 LEDs: potentially 15A at 5V - so you need at least 75W.

I'm using a 5V 10A laptop-style adapter. Combined with a barrel jack connector, it plugs straight into the Athom controller - no wire crimping needed.

The Athom controller comes with two cables: 4-pin and 3-pin. The 4-pin is for LEDs that need a clock signal. WS2812B doesn't, so use the 3-pin (power, ground, data).

The matrix has matching JST connectors - plug and play. Connect the barrel jack to the controller, plug in the adapter.

Done. Under 2 minutes.

The Athom creates its own WiFi network on first boot. Connect with your phone, enter your home WiFi credentials in the popup (or browse to 4.3.2.1).

Set a hostname like christmas - you can then access it at christmas.local instead of an IP address.

Open WLED in your browser and go to Config > LED Preferences:

Go to Config > 2D Configuration:

If your effects look wrong, you probably need to adjust:

Test tip: Use the "Scrolling Text" effect. If text reads correctly left-to-right, your config is right.

WLED has dozens of built-in effects. Save your favorites as presets for quick access.

You don't even need a browser - the WLED app (iOS / Android) finds any WLED device on your network automatically.

That's it. The power calculations and WLED configuration apply to any addressable LED project - Christmas lights, ambient lighting, whatever you're building.

Resources: