DescriptionThe Adafruit DS3231 Precision RTC FeatherWing adds a highly accurate I2C real-time clock to Adafruit Feather boards. The DS3231 combines an RTC, integrated crystal, and temperature compensation so timekeeping stays stable even as temperature changes.With a CR1220 12mm coin cell, the DS3231 RTC FeatherWing can keep time for years when main power is removed. That makes it useful for data logging, clocks, timestamps, sleep-mode projects, and measurement systems built with an Adafruit Feather board or prototyping setups using the FeatherWing Proto.The battery is required for backup operation, but Adafruit does not include it by default.Features DS3231 Precision RTC with temperature-compensated crystal oscillator. I2C interface for Feather boards. CR1220 battery holder for backup timekeeping. Supports Arduino and CircuitPython examples from the Adafruit Learn Guide. FeatherWing form factor for Feather-based data loggers and clocks. Reset button and compact 50.8mm x 22.9mm board. Specifications OpenELAB SKU Adafruit-3028 Official Product Name DS3231 Precision RTC FeatherWing - RTC Add-on For Feather Boards Product Type RTC FeatherWing add-on RTC Chip DS3231 with TCXO Interface I2C Backup Battery CR1220 12mm coin cell required for backup, not included Compatibility Adafruit Feather boards and FeatherWing stacking/female headers Software Arduino and CircuitPython examples according to Adafruit Learn Guide Dimensions 50.8 x 22.9 x 1.6 mm Weight 4.8g Revision Note PCB updated January 17, 2023 with Adafruit Pinguin silkscreen; function is identical Applications Data loggers with accurate timestamps. Feather-based clocks and calendar projects. Low-power sensor nodes that keep time during sleep mode. Measurement, lab, and classroom projects using I2C RTC hardware. Product List 1 x Adafruit DS3231 Precision RTC FeatherWing CR1220 battery, Feather board, and headers are not included unless separately specified Other ContentThe images below show the Adafruit DS3231 Precision RTC FeatherWing, battery holder, header options, and typical Feather setups.Resources Adafruit DS3231 FeatherWing downloads DS3231 datasheet Adafruit PCB files on GitHub FAQIs a CR1220 battery included?No. A CR1220 battery is required for backup timekeeping, but it is not included.Which interface does the RTC FeatherWing use?The board uses I2C and is designed for Adafruit Feather boards.Why is the DS3231 more accurate than simple RTCs?The DS3231 integrates the crystal and a temperature sensor, then compensates for temperature-related frequency drift.Does it work with CircuitPython?Yes. Adafruit provides Learn Guide examples for both Arduino and CircuitPython.What projects is this FeatherWing best for?It is useful for data loggers, clocks, timestamps, and low-power systems that need to keep time without main power.
