Low-cost, extremely accurate I2C real-time clock (RTC) with an integrated temperature-compensated crystal oscillator (TCXO) and crystal The device features a battery input to maintain accurate timekeeping when the main power supply is disconnected Integrated oscillator improves long-term accuracy and reduces the number of components required on the production line DS3231 available in commercial and industrial temperature ranges, housed in a 16-pin 300mil SO package RTC maintains seconds, minutes, hours, day, date, month, and year information; automatically adjusts for months with fewer than 31 days, including leap year corrections Clock operates in either 24-hour format or 12-hour format with AM/PM indicator Provides two configurable alarm clocks and a programmable square-wave output Address and data are transferred serially through an I2C bidirectional bus Precision temperature-compensated voltage reference and comparator circuit monitor VCC to detect power failures, provide reset output, and automatically switch to backup power if needed /RST pin supports manual microprocessor reset In addition to timekeeping and high precision, DS3231 includes extended features for enhanced system functionality Integrated digital temperature sensor accessible via I2C interface (same bus used for time data) Temperature sensor accuracy is 3C On-chip power supply control circuit automatically detects and manages switching between main and backup power (e.g., low-voltage battery) Device continues to provide accurate time and temperature during main power failure without performance degradation On-chip reset function restarts the system microprocessor when main power is restored or voltage returns to within acceptable range Module specifications: Size: 38mm (L) x 22mm (W) x 14mm (H) Operating voltage: 3.3V - 5.5V Clock chip: High-precision DS3231 Clock accuracy: Up to 2ppm in 0C to 40C range, approximately 1 minute per year error Features two calendar alarm clocks Programmable square-wave output Real-time clock provides seconds, minutes, hours, day, date, month, and year with leap-year compensation valid up to year 2100 Integrated temperature sensor with 3C accuracy Memory chip: AT24C32 (32K bit storage capacity) I2C bus interface, maximum transmission speed 400kHz (at 5V operating voltage) Supports cascading with other I2C devices; AT24C32 address can be modified via A0/A1/A2 pins; default address is 0x57 Includes rechargeable LIR2032 battery to maintain clock operation during power loss Wiring example: SCL A5, SDA A4, VCC 5V, GND GND Quantity: 1 piece