# Adafruit Metro ESP32-S3 > Arduino UNO-compatible Metro board with ESP32-S3 dual-core 240 MHz, 16 MB flash, 8 MB Octal PSRAM, WiFi, BLE 5, native USB-C, STEMMA QT, LiPoly charging, and JTAG debug header. ## Quick Facts - **Brand:** Adafruit - **Board Type:** dev-board - **Price:** ~$24.95 - **Product Readiness:** developer - **CPU:** Xtensa LX7 dual-core @ 240 MHz (ESP32-S3) - **CPU Architecture:** Xtensa LX7 - **CPU Cores:** 2 - **RAM:** 512 KB SRAM + 8 MB PSRAM - **PSRAM:** 8MB OPI - **Flash:** 16MB - **Power:** 5V + LiPo - **Operating Voltage:** 3.3V - **Battery:** user-supplied LiPo - **Antenna:** built-in PCB antenna ## Connectivity - **Wifi:** 2.4GHz 802.11 b/g/n - **Bluetooth:** BLE 5.0 ## Open Source - **Firmware:** Yes - **Schematics:** Yes - **PCB Layout:** Yes ## Compatible Firmware circuitpython, arduino, esp-idf ## Use Cases - iot - smart-home - environmental-monitoring ## Components - **ESP32-S3** (mcu): Espressif ESP32-S3 dual-core 240 MHz Xtensa LX7 with 512 KB SRAM, 8 MB Octal PSRAM, native USB OTG, WiFi, and BLE 5. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.espressif.com%2Fsites%2Fdefault%2Ffiles%2Fdocumentation%2Fesp32-s3_datasheet_en.pdf&ref=openhardware.directory&product=adafruit-metro-esp32-s3&source=md-export) - **MAX17048** (battery-charger): Maxim MAX17048 Li-Ion/LiPo fuel gauge providing state-of-charge via I2C. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.analog.com%2Fmedia%2Fen%2Ftechnical-documentation%2Fdata-sheets%2FMAX17048-MAX17049.pdf&ref=openhardware.directory&product=adafruit-metro-esp32-s3&source=md-export) ## Protocols - **I2C**: SDA: GPIO33, SCL: GPIO34 - **I2C (STEMMA QT)**: SDA: GPIO33, SCL: GPIO34 - **SPI**: MOSI: GPIO35, MISO: GPIO37, SCK: GPIO36 - **UART**: TX: GPIO43, RX: GPIO44 - **USB**: - **JTAG**: ## GPIO Map | Pin | Name | Type | Functions | |-----|------|------|-----------| | GPIO1 | RX | UART | UART, GPIO | | GPIO2 | TX | UART | UART, GPIO | | GPIO3 | GPIO | GPIO | GPIO | | GPIO4 | GPIO | GPIO | GPIO, PWM | | GPIO5 | GPIO | GPIO | GPIO | | GPIO6 | GPIO | GPIO | GPIO, PWM | | GPIO7 | GPIO | GPIO | GPIO, PWM | | GPIO8 | GPIO | GPIO | GPIO | | GPIO9 | GPIO | GPIO | GPIO | | GPIO10 | GPIO | GPIO | GPIO, PWM | | GPIO11 | GPIO | GPIO | GPIO, PWM | | GPIO12 | GPIO | GPIO | GPIO, PWM | | GPIO13 | GPIO | GPIO | GPIO | | GPIO14 | GPIO | GPIO | GPIO | | GPIO17 | ADC | ADC | ADC | | GPIO18 | ADC | ADC | ADC | | GPIO15 | ADC | ADC | ADC | | GPIO16 | ADC | ADC | ADC | | GPIO19 | ADC | ADC | ADC | | GPIO20 | ADC | ADC | ADC | | GPIO33 | SDA | I2C | I2C, STEMMA QT | | GPIO34 | SCL | I2C | I2C, STEMMA QT | | GPIO35 | MOSI | SPI | SPI | | GPIO37 | MISO | SPI | SPI | | GPIO36 | SCK | SPI | SPI | | GPIO43 | TX | UART | UART | | GPIO44 | RX | UART | UART | ## Available Software - **[CircuitPython](https://openhardware.directory/r?to=https%3A%2F%2Fcircuitpython.org%2Fboard%2Fadafruit_metro_esp32s3%2F&ref=openhardware.directory&product=adafruit-metro-esp32-s3&source=md-export)** - **[Arduino ESP32](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2Fespressif%2Farduino-esp32&ref=openhardware.directory&product=adafruit-metro-esp32-s3&source=md-export)** ## Description ## Overview The Adafruit Metro ESP32-S3 brings the ESP32-S3 dual-core 240 MHz SoC to the Arduino UNO-shape Metro form factor with a generous 16 MB of Flash and 8 MB of Octal PSRAM. This is Adafruit's most capable Metro for WiFi and BLE projects, and the UNO-shape guarantees compatibility with the thousands of Arduino shields already available. Native USB-C via the ESP32-S3's hardware USB OTG enables keyboard, mouse, MIDI, and mass-storage emulation without a bridge chip. A JTAG 2×5 header provides hardware debugging access alongside Reset and DFU buttons for standard bootloader entry. The STEMMA QT / Qwiic connector offers solderless I2C expansion with switchable power. The MAX17048 fuel-gauge chip monitors an optional LiPoly battery, and the onboard charger keeps it topped up from USB-C — making the Metro ESP32-S3 suitable for panel-mounted or remote-deployment projects where AC power is interrupted. Deep sleep current of approximately 100 µA enables extended battery operation. Note: hardware revision B (introduced November 2023) corrected PSRAM pin conflicts present in revision A, which caused instability when PSRAM and certain GPIO were used simultaneously. Boards purchased after that date should be revision B. CircuitPython, Arduino (ESP32 core), and ESP-IDF are all supported. ## Where to Buy - [Adafruit](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F5500&ref=openhardware.directory&product=adafruit-metro-esp32-s3&source=md-export) — 24.95 ## Resources - [product](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F5500&ref=openhardware.directory&product=adafruit-metro-esp32-s3&source=md-export) - [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2Fadafruit%2FAdafruit-Metro-ESP32-S3-PCB&ref=openhardware.directory&product=adafruit-metro-esp32-s3&source=md-export) - [learn guide](https://openhardware.directory/r?to=https%3A%2F%2Flearn.adafruit.com%2Fadafruit-metro-esp32-s3&ref=openhardware.directory&product=adafruit-metro-esp32-s3&source=md-export) ## Tags `esp32-s3`, `metro`, `arduino-shield`, `stemma-qt`, `circuitpython`, `wifi`, `ble`, `psram`, `lipo`, `jtag` ## Images ![Adafruit Metro ESP32-S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-metro-esp32-s3/b3781321d116.jpg) ![Adafruit Metro ESP32-S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-metro-esp32-s3/c89d8fbae932.jpg) ![Adafruit Metro ESP32-S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/adafruit-metro-esp32-s3/81decc50eeef.jpg) > **Battery Powered:** Li-Po --- [View full device page](https://openhardware.directory/devices/adafruit-metro-esp32-s3)