NeoPixel Ring 60 with an ESP32 DevKit V1
A ring of 60 individually addressable 5050 RGB LEDs (WS2812B) driven over a single data wire.
A 60-pixel ring is a power project first: on the ESP32 DevKit V1 the page feeds it from VIN at brightness 25, with data from GPIO13 through a 74AHCT125 buffer and a 470 Ohm resistor. At full white it needs its own 5 V supply, and the buffer takes care of the ESP32's 3.3 V data.
Wiring the NeoPixel Ring 60 to the ESP32 DevKit V1
Pin by pin.
| NeoPixel Ring 60 | ESP32 DevKit V1 | Note |
|---|---|---|
| VCC | VIN | |
| GND | GND | |
| DIN | GPIO13 (D13) | through a 74AHCT125 buffer powered from 5 V, then the 470 Ω resistor: the WS2812B reads a high from 0.7 × VDD (3.5 V), above a 3.3 V pin |
- VCC is on VIN, which gives about 5 V only while the board is powered from USB.
- At full brightness the 60 pixels draw up to about 3.6 A (60 mA each at full white), far more than USB gives through the board. The sketch caps brightness at 25 of 255, about 0.35 A. To go brighter, power VCC from its own 5 V supply rated 4 A or more and join its GND to the board's.
What to know on the ESP32 DevKit V1
- With a 60-pixel ring on a separate supply, the 3.3 V data from GPIO13 still meets a 0.7 x VDD threshold, about 3.5 V at 5 V. That is the job of the 74AHCT125 on DIN, powered from 5 V, ahead of the 470 Ohm resistor.WS2812B datasheet, p. 3
- Sixty pixels at full white come to about 3.6 A, some fifteen times the ESP32's own 240 mA Wi-Fi transmit figure and far more than a USB port can push through VIN. Only the sketch's setBrightness(25), about 0.35 A at full white, makes the USB-powered test safe.Adafruit NeoPixel Uberguide, Powering NeoPixels; Espressif ESP32 Series Datasheet v5.3, p. 52
- Adafruit NeoPixel hands each frame to the ESP32's RMT peripheral, so even a long 60-pixel frame keeps its timing with Wi-Fi active.Espressif ESP32 Series Datasheet v5.3, p. 38
- A 60-pixel frame is 60 x 24 bits at 800 kbps, about 1.8 ms per show(), so the sketch's 10 ms rainbow step leaves the ESP32 most of each cycle for Wi-Fi and other work.WS2812B datasheet (Worldsemi), p. 1
NeoPixel Ring 60 code for the ESP32 DevKit V1
Compiled for esp32:esp32:esp32 on 2026-10-30.
// NeoPixel Ring 60 on ESP32 DevKit V1: wiring and a free simulation at https://www.tinkered.ai/components/neopixel-ring-60/esp32
#include <Adafruit_NeoPixel.h>
#define LED_PIN 13
#define LED_COUNT 60
Adafruit_NeoPixel ring(LED_COUNT, LED_PIN, NEO_GRB + NEO_KHZ800);
void setup() {
ring.begin();
ring.setBrightness(25); // 25 of 255: full white on all 60 pixels then draws about 0.35 A, inside
// USB's 500 mA. Raise it only with an external 5 V supply.
ring.show();
}
void loop() {
// Rainbow effect
for (long firstPixel = 0; firstPixel < 65536; firstPixel += 256) {
for (int i = 0; i < ring.numPixels(); i++) {
int hue = firstPixel + (i * 65536L / ring.numPixels());
ring.setPixelColor(i, ring.gamma32(ring.ColorHSV(hue)));
}
ring.show();
delay(10);
}
}
NeoPixel Ring 60 on the ESP32 DevKit V1: questions
Does the NeoPixel Ring 60 work with the ESP32's 3.3 V data?
On a short wire it may, but GPIO13's 3.3 V sits under the 3.5 V high a 5 V WS2812B expects (0.7 x VDD, WS2812B datasheet, p. 3). With 60 pixels and a separate supply, the 74AHCT125 buffer the page puts on DIN is the safe choice.
Can the ESP32's VIN pin power the NeoPixel Ring 60?
No. 60 pixels at full white can draw about 3.6 A (Adafruit Uberguide); VIN on USB is only suitable at the very low brightness the sketch sets. Give the ring a 5 V supply rated for the worst case, join grounds, and keep GPIO13 on DIN.
Why do the far pixels of my 60 ring flicker on the ESP32?
Usually power: at full white the ring draws about 3.6 A (Adafruit Uberguide), and voltage drops along the ring. Feed 5 V at more than one point from a proper supply, add a 1000 µF capacitor across its supply, and level-shift DIN.
Keep going
This guide as plain Markdown. /components/neopixel-ring-60/esp32.md