Adafruit QT Py ESP32-C3 WiFi Dev Board with STEMMA QT

Adafruit Industries, MIT

What's life without a little RISC? This miniature dev board is perfect for small projects: it comes with our favorite connector - the STEMMA QT, a chainable I2C port, WiFi, Bluetooth® LE, and plenty of FLASH and RAM memory for many IoT projects. What a cutie pie! Or is it...

USB-C port
USB-C connector used for both powering and programming the QT Py ESP32-C3 board.
Type · powerVoltage · USB 5V input
3.3V
Output from the 3.3V regulator. Adafruit states these pins can supply 500mA peak.
Type · powerVoltage · 3.3V regulated output
GND
Common ground for all power and logic.
Type · powerVoltage · 0V ground reference
5V
5V output from the USB port. Adafruit also documents using the 5V pin as a protected external voltage input with a diode.
Type · powerVoltage · 5V USB rail; external input only with diode protection per Adafruit guidance
A0
ADC1 analog input and GPIO #4.
Type · analog

Start wiring

Analog · I2C · UART · USB 5V input · 3.3V regulated output

Confirm the data interface matches your host board.

Module pins: USB-C port, 3.3V, GND, 5V, STEMMA QT 3.3V, STEMMA QT GND, A0, A1. Schematik maps them to your board in the app.

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Pin	Type	Function	Voltage
USB-C port	power	USB-C connector used for both powering and programming the QT Py ESP32-C3 board.	USB 5V input
3.3V	power	Output from the 3.3V regulator. Adafruit states these pins can supply 500mA peak.	3.3V regulated output
GND	power	Common ground for all power and logic.	0V ground reference
5V	power	5V output from the USB port. Adafruit also documents using the 5V pin as a protected external voltage input with a diode.	5V USB rail; external input only with diode protection per Adafruit guidance
A0	analog	ADC1 analog input and GPIO #4.
A1	analog	ADC1 analog input and GPIO #3.
A2	analog	ADC1 analog input and GPIO #1.
A3	analog	ADC1 analog input and GPIO #0.
SCL	signal	I2C clock pin, shared by the STEMMA QT connector. Adafruit notes there is no pull-up on this pin. GPIO #6.
SDA	signal	I2C data pin, shared by the STEMMA QT connector. Adafruit notes there is no pull-up on this pin and SDA is also an ADC2 input. GPIO #5.
RX	signal	UART receive pin. Connect to TX on a sensor or breakout. GPIO #20.
TX	signal	UART transmit pin and hardware UART debug output. Connect to RX on a sensor or breakout. GPIO #21.
SCK	signal	SPI clock pin. GPIO #10.
MI	signal	SPI microcontroller-in / sensor-out pin. GPIO #8.
MO	signal	SPI microcontroller-out / sensor-in pin.
STEMMA QT SCL	signal	JST SH 4-pin STEMMA QT connector I2C clock line, shared with board SCL.	3.3V logic
STEMMA QT SDA	signal	JST SH 4-pin STEMMA QT connector I2C data line, shared with board SDA.	3.3V logic
STEMMA QT 3.3V	power	3.3V rail on the JST SH 4-pin STEMMA QT connector.	3.3V
STEMMA QT GND	power	Ground on the JST SH 4-pin STEMMA QT connector.	0V ground reference
NeoPixel	signal	On-board RGB NeoPixel status LED, available as board.NEOPIXEL / PIN_NEOPIXEL. Adafruit states it is on GPIO #2.
Boot button / GPIO 9	control	Boot button for ROM bootloader mode. Adafruit states it can also be read as GPIO 9 with input pull-up.
Reset button	control	Reset button restarts the board and helps enter the ROM bootloader.

Pinout

Start wiring

Connectors

Displays

Air quality

MCUs and boards