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Adafruit QT Py ESP32-S3 WiFi Dev Board with STEMMA QT

OverviewAlternates
Adafruit QT Py ESP32-S3 WiFi Dev Board with STEMMA QT - Adafruit - 5426

Seeed Xiao-form-factor board with dual-core ESP32-S3 at 240 MHz, 8 MB flash, 512 KB SRAM, 2.4 GHz Wi-Fi, BLE, native USB-C, and STEMMA QT I2C connector. Operates at 3.3 V. Choose this over the S2 variant when Bluetooth is needed.

Parts tray full · 5 max · remove a part to add another
Adafruit QT Py ESP32-S3 WiFi Dev Board with STEMMA QT — Adafruit — 5426
STEP

Offers

  • Adafruit$12.50
  • ?DigiKey$12.50

Offers

  • Adafruit$12.50
  • ?DigiKey$12.50

Pinout

Logical pinout · physical placement not verified
ADAFRUIT QT PY ESP32-SUSB-C portRX3.3VTXGNDSCK5VMIBATMOA0STEMMA QT SCL1A1STEMMA QT SDA1A2STEMMA QT 3.3VA3STEMMA QT GNDSCLBoot buttonGPIO 0SDAReset button
  • USB-C port

    USB-C connector used for powering and programming the QT Py ESP32-S3 board.

    Type · PowerVoltage · USB 5V input from a USB-C cable
  • 3.3V

    Output from the on-board 3.3V regulator. Adafruit states these pins can supply 600mA peak.

    Type · PowerVoltage · 3.3V regulated output
  • GND

    Common ground for all power and logic on the board.

    Type · GroundVoltage · 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 between the source and the pin.

    Type · PowerVoltage · 5V USB rail; external input only with diode protection per Adafruit guidance
  • BAT

    Back-side battery input pad paired with GND for external battery packs.

    Type · PowerVoltage · 3V to 6V battery input per Adafruit pinouts page
  • A0

    GPIO/analog input pad. Adafruit states A0 through A3 can be analog inputs.

    Type · Analog
  • A1

    GPIO/analog input pad. Adafruit states A0 through A3 can be analog inputs.

    Type · Analog
  • A2

    GPIO/analog input pad. Adafruit states A2 can also do capacitive touch.

    Type · Analog
  • A3

    GPIO/analog input pad. Adafruit states A3 can also do capacitive touch.

    Type · Analog
  • SCL

    Main I2C clock pad. Adafruit notes this is not shared with the STEMMA QT connector and has no pull-up on the pin. Also supports capacitive touch and analog input.

    Type · I2C
  • SDA

    Main I2C data pad. Adafruit notes this is not shared with the STEMMA QT connector and has no pull-up on the pin. Also supports capacitive touch and analog input.

    Type · I2C
  • RX

    UART receive pin. Connects to the transmit pin on a sensor or breakout.

    Type · UART
  • TX

    UART transmit pin. Connects to the receive pin on a sensor or breakout. Adafruit notes TX can also do capacitive touch.

    Type · UART
  • SCK

    SPI clock pin on the ESP32-S3 high-speed peripheral.

    Type · SPI
  • MI

    SPI microcontroller-in / sensor-out pin.

    Type · Signal
  • MO

    SPI microcontroller-out / sensor-in pin.

    Type · Signal
  • STEMMA QT SCL1

    JST SH 4-pin STEMMA QT connector clock line. Adafruit states the connector breaks out a second I2C interface: SCL1, SDA1, 3.3V and GND.

    Type · SignalVoltage · 3.3V logic on STEMMA QT connector
  • STEMMA QT SDA1

    JST SH 4-pin STEMMA QT connector data line. Adafruit states the connector breaks out a second I2C interface: SCL1, SDA1, 3.3V and GND.

    Type · SignalVoltage · 3.3V logic on STEMMA QT connector
  • STEMMA QT 3.3V

    3.3V rail on the JST SH STEMMA QT connector.

    Type · PowerVoltage · 3.3V
  • STEMMA QT GND

    Ground on the JST SH STEMMA QT connector.

    Type · PowerVoltage · 0V ground reference
  • Boot buttonGPIO 0

    Boot/DFU button. Adafruit states it can put the board into ROM bootloader mode and can be read as GPIO 0 with input pull-up.

    Type · GPIO, Control
  • Reset button

    Reset button restarts the board and helps enter the UF2 bootloader when tapped during the NeoPixel status LED boot indication.

    Type · Control
PinTypeFunctionVoltage
USB-C portPowerUSB-C connector used for powering and programming the QT Py ESP32-S3 board.USB 5V input from a USB-C cable
3.3VPowerOutput from the on-board 3.3V regulator. Adafruit states these pins can supply 600mA peak.3.3V regulated output
GNDGroundCommon ground for all power and logic on the board.0V ground reference
5VPower5V output from the USB port. Adafruit also documents using the 5V pin as a protected external voltage input with a diode between the source and the pin.5V USB rail; external input only with diode protection per Adafruit guidance
BATPowerBack-side battery input pad paired with GND for external battery packs.3V to 6V battery input per Adafruit pinouts page
A0AnalogGPIO/analog input pad. Adafruit states A0 through A3 can be analog inputs.
A1AnalogGPIO/analog input pad. Adafruit states A0 through A3 can be analog inputs.
A2AnalogGPIO/analog input pad. Adafruit states A2 can also do capacitive touch.
A3AnalogGPIO/analog input pad. Adafruit states A3 can also do capacitive touch.
SCLI2CMain I2C clock pad. Adafruit notes this is not shared with the STEMMA QT connector and has no pull-up on the pin. Also supports capacitive touch and analog input.
SDAI2CMain I2C data pad. Adafruit notes this is not shared with the STEMMA QT connector and has no pull-up on the pin. Also supports capacitive touch and analog input.
RXUARTUART receive pin. Connects to the transmit pin on a sensor or breakout.
TXUARTUART transmit pin. Connects to the receive pin on a sensor or breakout. Adafruit notes TX can also do capacitive touch.
SCKSPISPI clock pin on the ESP32-S3 high-speed peripheral.
MISignalSPI microcontroller-in / sensor-out pin.
MOSignalSPI microcontroller-out / sensor-in pin.
STEMMA QT SCL1SignalJST SH 4-pin STEMMA QT connector clock line. Adafruit states the connector breaks out a second I2C interface: SCL1, SDA1, 3.3V and GND.3.3V logic on STEMMA QT connector
STEMMA QT SDA1SignalJST SH 4-pin STEMMA QT connector data line. Adafruit states the connector breaks out a second I2C interface: SCL1, SDA1, 3.3V and GND.3.3V logic on STEMMA QT connector
STEMMA QT 3.3VPower3.3V rail on the JST SH STEMMA QT connector.3.3V
STEMMA QT GNDPowerGround on the JST SH STEMMA QT connector.0V ground reference
Boot buttonGPIO 0GPIO, ControlBoot/DFU button. Adafruit states it can put the board into ROM bootloader mode and can be read as GPIO 0 with input pull-up.
Reset buttonControlReset button restarts the board and helps enter the UF2 bootloader when tapped during the NeoPixel status LED boot indication.
Logical pinout · physical placement not verified
ADAFRUIT QT PY ESP32-SUSB-C portRX3.3VTXGNDSCK5VMIBATMOA0STEMMA QT SCL1A1STEMMA QT SDA1A2STEMMA QT 3.3VA3STEMMA QT GNDSCLBoot buttonGPIO 0SDAReset button

Pin details

22 connections
  1. USB-C port

    USB-C connector used for powering and programming the QT Py ESP32-S3 board.

    PowerVoltage · USB 5V input from a USB-C cable
  2. 3.3V

    Output from the on-board 3.3V regulator. Adafruit states these pins can supply 600mA peak.

    PowerVoltage · 3.3V regulated output
  3. GND

    Common ground for all power and logic on the board.

    GroundVoltage · 0V ground reference
  4. 5V

    5V output from the USB port. Adafruit also documents using the 5V pin as a protected external voltage input with a diode between the source and the pin.

    PowerVoltage · 5V USB rail; external input only with diode protection per Adafruit guidance
  5. BAT

    Back-side battery input pad paired with GND for external battery packs.

    PowerVoltage · 3V to 6V battery input per Adafruit pinouts page
  6. A0

    GPIO/analog input pad. Adafruit states A0 through A3 can be analog inputs.

    Analog
  7. A1

    GPIO/analog input pad. Adafruit states A0 through A3 can be analog inputs.

    Analog
  8. A2

    GPIO/analog input pad. Adafruit states A2 can also do capacitive touch.

    Analog
  9. A3

    GPIO/analog input pad. Adafruit states A3 can also do capacitive touch.

    Analog
  10. SCL

    Main I2C clock pad. Adafruit notes this is not shared with the STEMMA QT connector and has no pull-up on the pin. Also supports capacitive touch and analog input.

    I2C
  11. SDA

    Main I2C data pad. Adafruit notes this is not shared with the STEMMA QT connector and has no pull-up on the pin. Also supports capacitive touch and analog input.

    I2C
  12. RX

    UART receive pin. Connects to the transmit pin on a sensor or breakout.

    UART
  13. TX

    UART transmit pin. Connects to the receive pin on a sensor or breakout. Adafruit notes TX can also do capacitive touch.

    UART
  14. SCK

    SPI clock pin on the ESP32-S3 high-speed peripheral.

    SPI
  15. MI

    SPI microcontroller-in / sensor-out pin.

    Signal
  16. MO

    SPI microcontroller-out / sensor-in pin.

    Signal
  17. STEMMA QT SCL1

    JST SH 4-pin STEMMA QT connector clock line. Adafruit states the connector breaks out a second I2C interface: SCL1, SDA1, 3.3V and GND.

    SignalVoltage · 3.3V logic on STEMMA QT connector
  18. STEMMA QT SDA1

    JST SH 4-pin STEMMA QT connector data line. Adafruit states the connector breaks out a second I2C interface: SCL1, SDA1, 3.3V and GND.

    SignalVoltage · 3.3V logic on STEMMA QT connector
  19. STEMMA QT 3.3V

    3.3V rail on the JST SH STEMMA QT connector.

    PowerVoltage · 3.3V
  20. STEMMA QT GND

    Ground on the JST SH STEMMA QT connector.

    PowerVoltage · 0V ground reference
  21. Boot buttonGPIO 0

    Boot/DFU button. Adafruit states it can put the board into ROM bootloader mode and can be read as GPIO 0 with input pull-up.

    GPIO, Control
  22. Reset button

    Reset button restarts the board and helps enter the UF2 bootloader when tapped during the NeoPixel status LED boot indication.

    Control

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