Adafruit ESP32-S3 Feather (4MB Flash, 2MB PSRAM)

Overview

The Adafruit ESP32-S3 Feather with 4 MB Flash and 2 MB PSRAM is the PSRAM-equipped sibling of the 8 MB no-PSRAM variant, offering an additional 2 MB of pseudo-static RAM for applications that need larger buffers — useful for JPEG decoding, audio streaming, or running multiple CircuitPython display libraries simultaneously.

Native USB-C via the ESP32-S3's hardware USB OTG allows the board to emulate keyboards, mice, MIDI devices, and mass-storage drives without a separate bridge chip. The UF2 bootloader makes firmware updates drag-and-drop simple. Both WiFi (2.4 GHz) and BLE 5 are supported simultaneously, and the standard Feather pinout ensures FeatherWing compatibility.

A MAX17048 fuel-gauge IC monitors the LiPoly battery state-of-charge over I2C, and the onboard charger keeps the cell topped up from USB-C. A STEMMA QT connector with switchable power, a NeoPixel with power control, Reset and DFU buttons, and On/Charge/User indicator LEDs are all included. Deep sleep current is approximately 100 µA.

This board is compatible with CircuitPython, Arduino (ESP32 core), and ESP-IDF. The 2 MB PSRAM makes it better suited than the no-PSRAM variant for projects using the ESP32-S3's camera interface, TensorFlow Lite Micro, or large in-memory datasets.