LuMini Ring Hookup Guide

Contributors: Englandsaurus
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The LuMini rings (3 inch, 2 inch, 1 inch) are a great way to add a ring of light to just about anything.

SparkFun LuMini LED Ring - 3 Inch (60 x APA102-2020)

SparkFun LuMini LED Ring - 3 Inch (60 x APA102-2020)

SparkFun LuMini LED Ring - 2 Inch (40 x APA102-2020)

SparkFun LuMini LED Ring - 2 Inch (40 x APA102-2020)

SparkFun LuMini LED Ring - 1 Inch (20 x APA102-2020)

SparkFun LuMini LED Ring - 1 Inch (20 x APA102-2020)


The LuMini line uses the same LED used on our Lumenati boards, the APA102, just in a smaller, 2.0x2.0 mm package. This allows for incredibly tight pixel densities, and thus, a more continuous ring of color. While the LuMini Rings come in different sizes, they all operate in a similar fashion.

Size of a APA102-2020 Package APA102, 5050 Package
Size of a APA102, 2020 Package Size of a APA102, 5050 Package

In this tutorial, we'll go over how to connect the LuMini rings up to more LuMini rings as well as other APA102 based products. We'll check out how to map out a ring of lights in software so we can get a little more creative with circular animations. We'll go over some things to consider as you string more and more lights together, and we'll also go over some neat lighting patterns to get you away from that standard rainbow pattern (if you have 16 million colors why would you use 255).

Required Materials

To follow along with this tutorial, you will need the following materials. You may not need everything though depending on what you have. Add it to your cart, read through the guide, and adjust the cart as necessary.

Choosing a Microcontroller

You'll need a microcontroller to control everything, however, there's a few things to consider when picking one out for the purpose of controlling a whole ton of LED's. The first thing is that, although they don't have to operate at a specific timing, APA102 LED's can transmit data really, really fast for LED's, like 20 MHz fast. So you should use a microcontroller fast enough to take advantage of this fact. Another thing to consider when you start getting into higher LED counts is the amount of RAM taken up by the LED frame. Each LED takes up 3 bytes of space in RAM, which doesn't sound like a lot, but if you're controlling 5000 LED's, well, you might need something with a bit more RAM than your traditional RedBoard. The below chart outlines the amount of LED's where you may start running into memory issues. Keep in mind that these are very generous estimates and will decrease depending on what other global variables are declared.

MicrocontrollerMax LED'sClock Speed
SparkFun RedBoard60016 MHz
Arduino Mega 2560260016 MHz
Pro Micro70016 MHz
SparkFun ESP8266 Thing27,000160 MHz
SparkFun ESP32 Thing97,000160 MHz or 240 MHz
Teensy 3.687,000180 MHz (240 MHz Overclock)

It's pretty easy to choose the ESP or Teensy when it comes to stuff like this, as you've got a ton of overhead in clock cycles to run wacky calculations for animations. However, if your project isn't all about lights, and you're just tossing a LuMini Ring on a project as an indicator, less powerful microcontrollers will suffice. Here are a few microcontrollers listed from the catalog. Depending on the development board, you may need to solder headers based on your personal preference.

Teensy 3.6 (Headers)

Teensy 3.6 (Headers)

SparkFun RedBoard - Programmed with Arduino

SparkFun RedBoard - Programmed with Arduino

Pro Micro - 5V/16MHz

Pro Micro - 5V/16MHz

SparkFun ESP32 Thing

SparkFun ESP32 Thing

Arduino Mega 2560 R3

Arduino Mega 2560 R3

SparkFun ESP8266 Thing - Dev Board (with Headers)

SparkFun ESP8266 Thing - Dev Board (with Headers)


SparkFun Thing Plus - ESP32 WROOM

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Selecting a Power Supply

In most cases, your LED installation is gonna pull more than your board can handle (Depending on brightness and animation, anywhere from 100-250 LED's can be too much for your board's voltage regulator to handle) so you should snag a sweet 5V power supply that's got enough wattage in the cottage for all of your LED's. Here are a few 5V power supplies listed in our catalog. Just make sure to get the appropriate cable and adapter when connecting to your power hungry LEDs.

Mean Well Switching Power Supply - 5VDC, 20A

Mean Well LED Switching Power Supply - 5VDC, 5A

Mean Well LED Switching Power Supply - 5VDC, 5A


Wall Adapter Power Supply - 5V DC 2A (Barrel Jack)

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You can either estimate the necessary size of your power supply by taking the amount of LED's and multiplying by 60 mA (0.06 A) which is the amount of current it takes to run an LED at full white. This calculation will give you the maximum amount of power your LED's could draw, but most of the time, this is a gross overestimate of the amount of power you'll actually end up consuming. Instead of calculating, I usually like to test my completed installation on a benchtop power supply using the brightest animation it'll be running, and then add 20 or 30 percent to give myself a little wiggle room if I want to turn the brightness up in the future.

Power Supply - 80W DC Switching Mode

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You will need a wire stripper, wire, soldering iron, solder, general soldering accessories. Tweezers are optional if you are soldering the surface mount decoupling capacitor to the back of the board.

Hook-Up Wire - Assortment (Solid Core, 22 AWG)

Hook-Up Wire - Assortment (Solid Core, 22 AWG)

Tweezers - Curved (ESD Safe)

Tweezers - Curved (ESD Safe)

Solder Lead Free - 15-gram Tube

Solder Lead Free - 15-gram Tube

Weller WLC100 Soldering Station

Weller WLC100 Soldering Station


Wire Strippers - 20-30AWG

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Suggested Reading

If you aren’t familiar with the following concepts, we recommend checking out these tutorials before continuing.


Light is a useful tool for the electrical engineer. Understanding how light relates to electronics is a fundamental skill for many projects.

How to Power a Project

A tutorial to help figure out the power requirements of your project.

Light-Emitting Diodes (LEDs)

Learn the basics about LEDs as well as some more advanced topics to help you calculate requirements for projects containing many LEDs.

Electric Power

An overview of electric power, the rate of energy transfer. We'll talk definition of power, watts, equations, and power ratings. 1.21 gigawatts of tutorial fun!

How to Work with Jumper Pads and PCB Traces

Handling PCB jumper pads and traces is an essential skill. Learn how to cut a PCB trace, add a solder jumper between pads to reroute connections, and repair a trace with the green wire method if a trace is damaged.