Adafruit DS3231 Precision RTC - STEMMA QT

The DS3231 is an Extremely Accurate I²C-Integrated Real Time Clock (RTC) with a TCXO/Crystal. Known for its precise timekeeping, this RTC is designed for use in a small, low-power package. Unlike most RTCs that rely on an external 32kHz timing crystal, the DS3231 integrates the crystal within the chip, along with a temperature sensor to compensate for temperature-induced frequency changes, ensuring highly accurate timekeeping.

This version comes with STEMMA QT connectors, making it easy to integrate without soldering. The sensor is mounted on a compact, breadboard-friendly breakout and can operate with both 3.3V and 5V logic levels, compatible with platforms like Feather, Raspberry Pi, Arduino, and Metro328.

The RTC offers battery backup functionality with a coin cell (CR1220), allowing it to maintain accurate time even during power loss. It is perfect for applications like data logging, clocks, or any project that requires precise timekeeping. The coin cell is not included by default but is readily available in the shop.

The DS3231 communicates via I²C, so it connects easily with just two wires (plus power and ground). It is also supported by CircuitPython/Python and Arduino drivers for seamless integration. The breakout board comes fully assembled and tested, with a small header included for easy connection to a breadboard or direct wiring.