# FeatherS3[D] ESP32-S3 by Unexpected Maker > The FeatherS3[D] is Unexpected Maker's Feather-form ESP32-S3 board with a dual antenna system (onboard + u.FL, software-switchable), I2C battery fuel gauge, 16MB flash, 8MB PSRAM, two STEMMA QT connectors, and LiPo charging — all in the standard Adafruit Feather footprint. ## Quick Facts - **Brand:** Unexpected Maker - **Board Type:** ESP32-S3 - **Price:** ~$24.95 - **Product Readiness:** developer - **CPU:** Xtensa LX7 dual-core @ 240MHz, FPU, AI vector extensions, HW crypto (AES/SHA/RSA) - **CPU Architecture:** Xtensa LX7 dual-core - **CPU Cores:** 2 - **RAM:** 512KB SRAM + 8MB PSRAM - **PSRAM:** 8MB QSPI - **Flash:** 16MB - **USB:** USB-C (native USB + USB Serial JTAG) - **Power:** USB-C 5V or LiPo battery - **Operating Voltage:** 3.3V GPIO - **Antenna:** u.FL + onboard PCB antenna (switchable) ## Connectivity - **Wifi:** 2.4GHz 802.11 b/g/n - **Bluetooth:** Bluetooth 5 LE + Mesh ## Open Source - **Firmware:** Yes - **Schematics:** Yes - **PCB Layout:** Yes ## Certifications CE, FCC, RoHS ## Compatible Firmware circuitpython, micropython, arduino, esp-idf ## Use Cases - iot - prototyping - smart-home - wearable ## Components - **ESP32-S3** (mcu): Dual-core Xtensa LX7 at 240MHz with AI vector extensions, WiFi 802.11 b/g/n, Bluetooth 5 LE+Mesh, and native USB OTG. — [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=feathers3d-esp32-s3&source=md-export) - **8MB PSRAM** (memory): External 8MB QSPI pseudo-static RAM for expanded working memory and large library support. — [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=feathers3d-esp32-s3&source=md-export) - **I2C Battery Fuel Gauge** (sensor): Dedicated I2C fuel gauge IC for accurate LiPo battery state-of-charge monitoring. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fesp32s3.com%2Ffeathers3.html&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export) - **RF Switch** (chip): Software-controlled RF switch allowing runtime selection between the onboard PCB antenna and the u.FL external antenna connector. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fesp32s3.com%2Ffeathers3.html&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export) - **RGB LED** (led): Built-in addressable RGB LED for status indication. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fcdn-shop.adafruit.com%2Fdatasheets%2FWS2812B.pdf&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export) ## Protocols - **I2C**: SDA: GPIO15, SCL: GPIO16 - **SPI**: MOSI: GPIO7, MISO: GPIO3, SCK: GPIO6 - **UART**: TX: GPIO1, RX: GPIO2 - **PWM** ## GPIO Map | Pin | Name | Type | Functions | |-----|------|------|-----------| | GPIO1 | TX | UART | uart-tx, digital | | GPIO2 | RX | UART | uart-rx, digital | | GPIO3 | MISO | SPI | spi-miso, digital | | GPIO4 | A4 | GPIO | analog, digital | | GPIO5 | A5 | GPIO | analog, digital | | GPIO6 | SCK | SPI | spi-sck, digital | | GPIO7 | MOSI | SPI | spi-mosi, digital | | GPIO8 | D5 | GPIO | digital | | GPIO9 | D6 | GPIO | digital | | GPIO10 | D9 | GPIO | digital | | GPIO11 | D10 | GPIO | digital | | GPIO12 | D11 | GPIO | digital | | GPIO13 | D12 | GPIO | digital | | GPIO14 | D13 | GPIO | digital | | GPIO15 | SDA | I2C | i2c-sda, digital | | GPIO16 | SCL | I2C | i2c-scl, digital | ## Available Software - **[CircuitPython](https://openhardware.directory/r?to=https%3A%2F%2Fcircuitpython.org%2Fboard%2Funexpectedmaker_feathers3%2F&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export)** - **[Getting Started Guide](https://openhardware.directory/r?to=https%3A%2F%2Fesp32s3.com%2Ffeathers3.html&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export)** ## Description ## Overview The FeatherS3[D] brings Unexpected Maker's dual-antenna "[D]" enhancements to the popular Adafruit Feather form factor, making it compatible with the vast ecosystem of FeatherWing add-on boards. The board centres on the ESP32-S3 with dual Xtensa LX7 cores at 240MHz, AI vector extensions, and native USB OTG, paired with 16MB of QSPI flash and 8MB of PSRAM for memory-intensive CircuitPython and AI-at-the-edge workloads. The hallmark [D] feature is the dual antenna system: an onboard high-gain PCB antenna and a u.FL connector for an external antenna, connected through an RF switch that is fully controllable from application code. The onboard antenna is selected by default, preventing accidental RF damage. A new I2C battery fuel gauge joins the existing LiPo charging circuit, giving developers precise state-of-charge readouts over I2C without extra breakout boards. Two STEMMA QT / Qwiic connectors offer back-to-back I2C expansion, and dual 700mA 3.3V LDO regulators deliver stable power to both the ESP32-S3 and any attached peripherals. A total of 21 GPIO pins are broken out, plus a built-in RGB LED and reverse back-feed protection on the USB-C port. The board ships with CircuitPython pre-installed and a UF2 bootloader for drag-and-drop firmware updates. The FeatherS3[D] is compatible with Arduino 2.0.3+, CircuitPython, ESP-IDF, and MicroPython. Unexpected Maker provides open-source schematics and PCB files on GitHub and comprehensive documentation at esp32s3.com. ## Where to Buy - [Adafruit](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F6399&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export) — $24.95 ## Resources - [product](https://openhardware.directory/r?to=https%3A%2F%2Fwww.adafruit.com%2Fproduct%2F6399&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export) - [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2Funexpectedmaker%2Fesp32s3&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export) - [wiki](https://openhardware.directory/r?to=https%3A%2F%2Fesp32s3.com%2Ffeathers3.html&ref=openhardware.directory&product=feathers3d-esp32-s3&source=md-export) ## Tags `unexpected-maker`, `esp32-s3`, `feathers3`, `feather`, `dual-antenna`, `psram`, `circuitpython`, `wifi`, `ble`, `ufl` ## Images ![FeatherS3[D] ESP32-S3 by Unexpected Maker](https://nbg1.your-objectstorage.com/openhardware-directory/entities/feathers3d-esp32-s3/cf0cd1b5bb51.jpg) ![FeatherS3[D] ESP32-S3 by Unexpected Maker](https://nbg1.your-objectstorage.com/openhardware-directory/entities/feathers3d-esp32-s3/1072a19e7166.jpg) ![FeatherS3[D] ESP32-S3 by Unexpected Maker](https://nbg1.your-objectstorage.com/openhardware-directory/entities/feathers3d-esp32-s3/e319a81c4359.jpg) --- [View full device page](https://openhardware.directory/devices/feathers3d-esp32-s3)