How to Use Adafruit NeoPixel FeatherWing: Examples, Pinouts, and Specs

The Adafruit NeoPixel FeatherWing is an add-on board for the Adafruit Feather ecosystem. It features a matrix of individually addressable RGB LEDs, commonly known as NeoPixels. These LEDs can be controlled with a single microcontroller pin and offer full 24-bit color, which allows for a wide range of color blending and animations. The FeatherWing is ideal for creating colorful and complex lighting effects for wearables, indicators, displays, and any project requiring a splash of vibrant color.

• Wearable electronics
• Decorative lighting
• Signal indicators
• Interactive art installations
• Educational projects teaching electronics and programming

• Operating Voltage: 3.3V to 5V
• Number of LEDs: 4x8 matrix, 32 total NeoPixels
• Communication: Single-wire digital interface
• Maximum Current Draw: ~60mA per LED at full brightness

1. Powering the FeatherWing: Connect the VBAT pin to a 3.3V to 5V power supply. Ensure that your power supply can handle the maximum current draw if all LEDs are at full brightness.
2. Data Connection: Connect the DIN pin to a digital output pin on your microcontroller.
3. Ground Connection: Connect the GND pin to the ground on your microcontroller.

• Always use a current-limiting resistor (about 300-500 Ohms) on the DIN pin to protect the NeoPixels.
• Include a large capacitor (1000µF, 6.3V or higher) across the power supply pins to prevent initial onrush of current from damaging the LEDs.
• Avoid powering the NeoPixels at full brightness for extended periods to prevent overheating.
• When chaining multiple NeoPixel devices, ensure that the power supply can handle the increased current draw.

#include <Adafruit_NeoPixel.h>

#define PIN            6 // The pin connected to the NeoPixels
#define NUMPIXELS      32 // Number of NeoPixels in the FeatherWing

// Create an instance of the Adafruit_NeoPixel class called "pixels"
Adafruit_NeoPixel pixels(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);

void setup() {
  pixels.begin(); // Initialize the NeoPixel library.
}

void loop() {
  for(int i=0; i<NUMPIXELS; i++) {
    pixels.setPixelColor(i, pixels.Color(0,150,0)); // Moderately bright green color.
    pixels.show(); // This sends the updated pixel color to the hardware.
    delay(500); // A half-second delay between each pixel set.
    pixels.setPixelColor(i, pixels.Color(0,0,0)); // Turn off the pixel.
  }
}

Ensure that the Adafruit NeoPixel library is installed in your Arduino IDE before uploading this code to your Arduino UNO.

• LEDs not lighting up: Check connections and ensure the power supply is adequate.
• Flickering LEDs: This may be due to a poor power supply or insufficient decoupling. Ensure capacitors are correctly installed.
• Incorrect colors: Verify that the data line is connected to the correct pin and that the code matches the type of NeoPixel being used.

• Double-check wiring, especially the ground connection.
• Use a multimeter to verify that the power supply is delivering the correct voltage.
• Reduce the brightness in your code to lower the current draw if the power supply is inadequate.
• Ensure that the Arduino library for NeoPixel is up to date.

Q: Can I use a 3.3V logic level with the NeoPixel FeatherWing?

A: Yes, the NeoPixel FeatherWing can typically understand 3.3V logic; however, for reliability, especially with longer wires, a logic level converter is recommended.

Q: How many NeoPixel FeatherWings can I chain together?

A: This depends on your power supply's capacity. Each NeoPixel can draw up to 60mA, so calculate your requirements accordingly.

Q: Can I cut the FeatherWing to fit a smaller space?

A: No, the FeatherWing is not designed to be cut. Doing so may damage the board and the NeoPixels.