Adafruit DS3231 Precision RTC Breakout

The DS3231 is an "Extremely Accurate I²C-Integrated RTC/TCXO/Crystal" as described in its datasheet, and it lives up to that claim! This Real-Time Clock (RTC) offers the highest precision available in a compact, low-power package.

Unlike most RTCs that use an external 32kHz timing crystal, which can experience slight drift—especially due to temperature changes—the DS3231 integrates the crystal directly into the chip. Additionally, it features a temperature sensor placed right next to the crystal. This sensor compensates for any temperature-induced frequency variations by adjusting the clock, ensuring accurate timekeeping.

This is the most precise RTC available, now available in a small, breadboard-friendly breakout board. With a coin cell battery, the DS3231 can maintain accurate time for years, even when the main power is lost, making it ideal for applications like datalogging, clocks, or projects where precise time is crucial.

The breakout board comes fully assembled and tested, with a small piece of header included. You can solder the header for easy breadboard connections or wire it directly.

Please note: a coin cell is required to utilize the battery backup feature. We don't include one by default to simplify international shipping, but we do offer CR1220 coin cells in the shop, or you can use one you already have.

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