Adafruit Feather STM32F405 Express

ST takes flight in this Feather board. The new STM32F405 Feather (video) that we designed runs CircuitPython at a blistering 168MHz – our fastest CircuitPython board ever! We put a STEMMA QT / Qwiic port on the end, so you can really easily plug and play I2C sensors.

GND
Common ground for all power and logic on the Feather STM32F405 Express board.
Type · groundVoltage · 0V reference; source states common ground for power and logic.
BAT
Positive voltage to/from the JST jack for the optional LiPoly battery.
Type · powerVoltage · Battery input/output; exact battery voltage not restated on pinouts page.
USB
Positive voltage to/from the USB-C jack when connected.
Type · powerVoltage · USB bus voltage; source identifies it as the USB-C positive voltage.
EN
3.3V regulator enable pin; pulled up, connect to ground to disable the 3.3V regulator.
Type · controlVoltage · 3.3V regulator enable control; pulled up per source.
3V
Output from the 3.3V regulator for board/peripheral power.

Start wiring

SPI · UART · I2C · 0V reference; source states common ground for power and logic. · Battery input/output; exact battery voltage not restated on pinouts page.

Confirm the data interface matches your host board.

Module pins: BAT, USB, 3V, STEMMA QT / Qwiic 3.3V, GND, STEMMA QT / Qwiic GND, SDA / GPIO 14 / PB7, SCL / GPIO 15 / PB6. Schematik maps them to your board in the app.

Related groups

4 groups

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Connectors & cables · Connectors · 28 parts

Displays

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Displays · TFT & LCD displays · 35 parts

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Boards · Microcontroller boards · 25 parts

Position

Type

Function

Voltage

GND

ground

Common ground for all power and logic on the Feather STM32F405 Express board.

0V reference; source states common ground for power and logic.

BAT

power

Positive voltage to/from the JST jack for the optional LiPoly battery.

Battery input/output; exact battery voltage not restated on pinouts page.

USB

power

Positive voltage to/from the USB-C jack when connected.

USB bus voltage; source identifies it as the USB-C positive voltage.

control

3.3V regulator enable pin; pulled up, connect to ground to disable the 3.3V regulator.

3.3V regulator enable control; pulled up per source.

power

Output from the 3.3V regulator for board/peripheral power.

3.3V output, source states it can supply 500mA peak.

RX / GPIO 0 / PB11

digital

UART receive pin for Serial3; also general-purpose 3.3V logic I/O.

3.3V logic; source notes nearly all GPIO pins are 5V compliant.

TX / GPIO 1 / PB10

digital

UART transmit pin for Serial3; also general-purpose 3.3V logic I/O.

3.3V logic; source notes nearly all GPIO pins are 5V compliant.

SDA / GPIO 14 / PB7

i2c

I2C Wire data pin with 10K pull-up to 3.3V; hardware I2C1.

3.3V pull-up on SDA per source.

SCL / GPIO 15 / PB6

i2c

I2C Wire clock pin with 10K pull-up to 3.3V; hardware I2C1.

3.3V pull-up on SCL per source.

SCK / GPIO 23

spi

Main SPI bus clock pin, hardware SPI2.

3.3V logic; source notes nearly all GPIO pins are 5V compliant.

MISO / GPIO 24

spi

Main SPI bus input data pin, hardware SPI2.

3.3V logic; source notes nearly all GPIO pins are 5V compliant.

MOSI / GPIO 25

spi

Main SPI bus output data pin, hardware SPI2.

3.3V logic; source notes nearly all GPIO pins are 5V compliant.

A0 / GPIO 16 / PA4

analog

Analogue input and DAC OUT1 true analogue output.

Analogue output can be set from 0V to 3.3V per source.

A1 / GPIO 17 / PA5

analog

Analogue input and DAC OUT2 true analogue output.

Analogue output can be set from 0V to 3.3V per source.

A2 / GPIO 18 / PA6

analog

Analogue input; alternate use SPI1 SCK.

3.3V analogue/GPIO domain; source notes general GPIO logic is 3.3V.

A3 / GPIO 19 / PA7

analog

Analogue input; alternate use SPI1 MISO.

3.3V analogue/GPIO domain; source notes general GPIO logic is 3.3V.

STEMMA QT / Qwiic 3.3V

power

JST SH STEMMA QT/Qwiic connector power rail.

3.3V on STEMMA QT/Qwiic connector per source.

STEMMA QT / Qwiic GND

ground

JST SH STEMMA QT/Qwiic connector ground.

0V reference.

STEMMA QT / Qwiic SDA

i2c

STEMMA QT/Qwiic connector I2C data, usable as board.SDA.

3.3V I2C connector rail per source.

STEMMA QT / Qwiic SCL

i2c

STEMMA QT/Qwiic connector I2C clock, usable as board.SCL.

3.3V I2C connector rail per source.

NeoPixel / GPIO 8

digital

On-board single NeoPixel data connection, Arduino pin #8 / board.NEOPIXEL.

Pinout

Start wiring

Connectors

Displays

Air quality

MCUs and boards