Neopixel Giant Edition

Meet Giant Neopixel, a scaled-up version of the popular WS2812B RGB addressable LED.

In our giant version, we used the exact drawing of the original 5050-package LED and recreated it as a 150×150 mm model that works just like its real counterpart.

To make this work, we designed a custom circuit built around a single WS2811 IC connected to nine 5050 RGB LEDs, all driven through a MOSFET-based switching stage. We even added large terminals that match the actual pads found on the WS2812B LED, so the whole thing looks and behaves like a supersized version of the original.

To complete the look, we poured clear epoxy over the electronics, just like how the real WS2812B encapsulates its RGB LEDs and addressable chip inside a 5050 epoxy package.

This article is a full walkthrough of how this project was designed and built, so let’s get started!

MATERIALS REQUIRED

The following were the materials used in this project:

• Custom PCBs (Provided by JLCPCB)
• WS2811 IC
• 5050 RGB LED
• 8205S Mosfet IC
• 10K Resistor
• 3-Ohm Resistor
• Seeed XIAO SAMD21 M0 MCU
• Breadboard
• connecting wires
• 3D Printed Parts
• Clear Epoxy Resin
• Aluminum sheet

WS2812B ADDRESSABLE LED

Before starting the project, let’s have a closer look at the WS2812B addressable LED. This is a component that I really enjoy using in my projects; in fact, I’ve made many builds based around WS2812B.

One of the main reasons is that, unlike a regular RGB LED that has a common anode or cathode pin along with three separate pins that control the R, G, and B channels, the WS2812B features a single data input pin that handles everything.

Inside the tiny 5050 package, the WS2812B actually contains three LED chips (red, green, and blue) and a built-in constant-current LED driver IC. This internal driver interprets a high-speed 800 kHz data signal, decodes color information for 24-bit RGB (8 bits per channel), and sets the brightness of each LED accordingly.

Another interesting detail is that WS2812B LEDs are designed to be daisy-chained: the Data Out pin automatically forwards the remaining data to the next LED in the chain. This means you can control hundreds or even thousands of LEDs using just a single microcontroller pin.

They also support PWM at around 400–800 Hz, which provides smooth color transitions, animations, and brightness control without visible flicker. Power-wise, each LED can draw up to 60 mA at full white (20 mA per channel), although most animations use much less.

3D DESIGN

We began the project by finding a clear top-view image of the WS2812B LED. This image was imported into Fusion 360 using the Canvas feature, and with the Calibrate tool we set the width and height to 150 mm, which is exactly 30 times larger than the real WS2812B.

After scaling, we traced the outline directly over the canvas reference to recreate the entire LED model within minutes.

In the middle, where the real WS2812B houses its components, we added a 98 mm circular PCB and modeled simple SMD parts that resemble the internal elements of the original LED. This reference layout helped us later position the RGB LEDs and the WS2811 control IC accurately on the actual PCB.

We also designed functional terminals just like the pads of a real WS2812B. For this, we used aluminum sheet pieces that were cut to shape following the dimensions from our CAD drawing. Each terminal piece was secured using two screws, and wires can be connected directly through these screw holes, effectively turning the aluminum pieces into VCC, GND, and DIN terminals for controlling the Giant Neopixel. After cutting the sheet with a hand tool, we drilled mounting holes and lightly sanded the pieces to give them a more realistic terminal-like finish.

Once the 3D body of the LED was complete, we exported it as a mesh file and 3D printed the enclosure on our Anycubic Kobra S1 using white high-speed PLA.

PCB DESIGN

We started the PCB design process by preparing the schematic for this project. The circuit uses the minimal configuration of the WS2811 IC, paired with three MOSFETs used as switching stages. For the MOSFETs, we selected the 8205S N-channel dual MOSFET IC, which we used to control the red, green, and blue channels.

Our design includes nine 5050 RGB LEDs. All LED anodes are tied to VCC, while their cathodes are grouped by color:

• All Red cathodes are connected in parallel to the first MOSFET
• All Green cathodes are connected in parallel to the second MOSFET
• All Blue cathodes are connected in parallel to the third MOSFET

The gates of the three MOSFETs are driven by the R, G, and B outputs of the WS2811 IC, each connected through a 10 kΩ gate resistor. Using MOSFETs allows us to drive much higher currents than the WS2811 could handle directly, which makes the entire LED assembly significantly brighter.

We added a CON1 connector with four pins to access VCC, GND, DIN, and DOUT, giving us complete support for daisy-chaining multiple Giant Neopixels if needed. To protect the LEDs and regulate brightness, we also placed current-limiting resistors between VCC and the anodes of the RGB LEDs.

Once the schematic was finalized, we exported the netlist and created the PCB layout. Using the dimensions from our CAD model, we traced the outline and placed all nine LEDs exactly in their assigned positions. After routing the connections and arranging all components, we completed the board by adding decorative elements on both the solder mask and silkscreen layers to give the PCB an artistic and polished look.

JLCCNC SERVICE

Codethe board design was finalized, I chose a purple solder mask with a white silkscreen and uploaded the Gerber files to JLCPCB’s quote page. I usually stick to white or black for most builds, but this time I wanted to switch things up—and the purple option looked too good to skip.

I’ve tried PCB services from different manufacturers over the years, and this time the boards arrived in under a week with a clean finish and sharp silkscreen. Everything aligned perfectly with the design, and the purple solder mask really made the PCB stand out.

Although this project didn’t require any CNC-machined parts, the overall build was supported by JLCCNC, who specialize in CNC machining, milling, and custom mechanical fabrication. Their platform lets you upload STEP files, choose materials, and get precision-machined parts delivered quickly. So if your project involves enclosures or custom hardware, JLCCNC can handle that side seamlessly.

Overall, the boards turned out great, and experimenting with the purple solder mask was absolutely worth it.

PCB ASSEMBLY

• The PCB assembly process starts by adding solder mask to each SMD component pad; we used a dispensing syringe filled with Sn-PB 63-37 solder mask.
• Next, we pick all the SMD components using ESD tweezers and place them in their correct location.
• The whole circuit is then placed on the reflow hotplate, which heats the PCB from below, and as the temperature gradually rises to about 200°C, the solder paste melts and securely holds every component in place.

LED TESTING

To ensure that all SMD components, especially the RGB LEDs, were soldered and connected correctly, we used a multimeter set to diode test mode.

We placed the multimeter’s positive probe on VCC and then touched the negative probe to the R, G, and B cathode pads one by one. Each color lit up, confirming that the LEDs were properly connected.

The blue LED produced only a faint glow, but it was still visible. This is expected because blue LEDs require a higher forward voltage, and most multimeters in diode mode cannot supply enough voltage to fully illuminate them. Even so, the slight glow was enough to verify that the connection was correct.

With all LEDs tested and confirmed, we moved on to the coding process.

TEST CODE

Below is the code we prepared for this project, and it's a simple one; we have used FastLED library-based code.

#include <FastLED.h>
#define NUM_LEDS 1
#define DATA_PIN 0
CRGB leds[NUM_LEDS];
void setup() {
FastLED.addLeds<WS2811, DATA_PIN, GRB>(leds, NUM_LEDS);
FastLED.setBrightness(255);
}
void loop() {
leds[0] = CRGB::White;   // R+G+B
FastLED.show();
delay(2000);
leds[0] = CRGB::Yellow;  // R+G (no blue)
FastLED.show();
delay(2000);
leds[0] = CRGB::Red;     // only R
FastLED.show();
delay(2000);
leds[0] = CRGB::Black;   // off
FastLED.show();
delay(2000);
}

CIRCUIT & BODY ASSEMBLY

• We begin the body and circuit assembly by soldering the connecting wires to the circuit’s VCC, GND, DIN, and DOUT terminals.
• Next, we applied double-sided thermal tape to the back of the circuit and press-fit the circuit into the center section of the main body.
• All the wires attached to the circuit are routed through the four openings provided in the middle area. These openings allow the wires to pass from the front side to the back side, where they will later be connected to the aluminum terminals.

TERMINAL ASSEMBLY

• We trimmed the excess length of each connecting wire, stripped the ends, and passed them through the screw hole in the aluminum sheet.
• Next, we wrapped the wire around the screw, positioned the aluminum sheet over its mounting spot, and tightened the screw. This creates pressure on the wire, forming a solid electrical connection and effectively turning the entire aluminum sheet piece into a large terminal.
• We repeated the same process for the remaining three terminals.

TESTING TERMINALS

Before moving to the final epoxy process, we first verified that the setup was working correctly. We used some magnetic holders we had lying around—these are normally used to screw something onto them and then attach the holder to any metal surface.

Since we used aluminum sheets for the terminals, and aluminum is not magnetic, you might wonder how we planned to make a connection.

The answer is simple: the screws we used are made of iron, and the magnetic holders stick to them perfectly.

We connected wires to the magnetic holders and paired them with the power lines from our XIAO board: 5V to VCC, GND to GND, and DIN to GPIO0. The circuit worked properly, confirming that everything was connected correctly.

With the functionality verified, we could now move on to the final step.

EPOXY PROCESS

To encase the electronics, our plan was to use clear epoxy, and for this we purchased a 2:1 epoxy kit. Inside the circular section of the body, we had four holes for wire routing. If we poured epoxy directly, it would simply leak out of these openings, so we sealed them with hot glue first.

After preparing the enclosure, we mixed the epoxy in the required 2:1 ratio and poured the entire mixture into the middle cavity. We let it cure for about 12 hours, and once hardened, it formed a solid, glass-like protective layer that not only looks great but also encapsulates all the electronics—just like the epoxy-filled 5050 package of a real WS2812B LED.

With this, the assembly process was officially completed.

RESULT

Here’s the end result of this simple yet massive build, a fully working, scaled-up WS2812B LED.

Just like its original counterpart, this giant version functions exactly the same, only at a much larger size. For testing, we paired it with a XIAO SAMD21 MCU to drive the LED, but in reality, any microcontroller can be used.

What makes this exciting is that we can even build multiple XL versions of this LED and chain them together using the DIN and DOUT pins, allowing us to control them just like a strip of normal addressable LEDs.

The possibilities for projects using this giant LED are endless. One idea I’ve been wanting to try is creating a wall-sized RGB matrix using multiple units, which I hope to build in the coming months.

CONCLUSION

This Giant WS2812B project marks the third and most refined version of an idea I’ve experimented with multiple times. The first version used just three 5050 LEDs directly driven by a WS2811 IC—simple, but far too underpowered without MOSFETs. The second attempt also skipped MOSFETs, and, to make things worse, I used yellow epoxy that completely ruined the look of the build.

This latest version finally brings everything together: a fully scaled-up model, high-brightness LEDs powered through MOSFETs, a far cleaner and more reliable circuit, and a clear epoxy finish that makes it look like a true oversized WS2812B.

Overall, this project was a fun challenge and a huge improvement over the previous attempts. With this foundation, I’m excited to explore even bigger ideas—maybe even an entire wall-sized RGB matrix in the future.

Huge thanks to JLCCNC for supporting this project. They offer CNC machining, milling, and custom mechanical fabrication with fast turnaround and consistent quality. If you’re working on enclosures, brackets, or any precision parts, definitely check out JLCCNC’s services!

Stay tuned for the upcoming update.

Thanks for reaching this far, and I will be back with a new project pretty soon.

Peace.