Low-cost, extremely accurate I2C real-time clock (RTC) with an integrated temperature-compensated crystal oscillator (TCXO) and crystal Device features a battery input to maintain accurate timekeeping when the main power supply is disconnected Integrated oscillator improves long-term accuracy and reduces component count on the production line DS3231 available in commercial and industrial temperature ranges, housed in a 16-pin 300mil SO package RTC tracks seconds, minutes, hours, day, date, month, and year; automatically adjusts for months with fewer than 31 days and includes leap year correction Clock operates in either 24-hour 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 via an I2C bidirectional bus Precision temperature-compensated voltage reference and comparator circuit monitor VCC for power failure detection, 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 system features Integrated digital temperature sensor accessible via I2C interface (same bus used for time data) Temperature sensor accuracy: ±3°C On-chip power supply control automatically detects and manages switching between main and backup power (e.g., low-voltage battery) Maintains accurate time and temperature during main power outages without performance degradation On-chip reset function restarts the system microprocessor when main power is restored or voltage returns to acceptable levels Note: Battery not included 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 0°C to 40°C range, resulting in approximately 1 minute per year error Features two calendar alarm clocks Programmable square-wave output Real-time clock keeps track of seconds, minutes, hours, day, date, month, and year with leap year compensation valid up to year 2100 Built-in temperature sensor with ±3°C accuracy Memory chip: AT24C32 (32K bit storage capacity) I2C bus interface with maximum transmission speed of 400kHz (at 5V operating voltage) Supports cascading with other I2C devices; AT24C32 address can be modified via A0/A1/A2 pins (default address 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