DS3231 IIC Precision Clock Module with Memory and Temperature Sensor

The DS3231 is a low-cost, high-precision I²C real-time clock (RTC) with an integrated temperature-compensated crystal oscillator (TCXO) and crystal. The device includes a battery input to maintain timekeeping when main power is removed. Integrated crystals improve accuracy and reduce component count in production.The DS3231 is available in commercial and industrial temperature ranges and comes in a 16-pin, 300-mil SO package. It stores seconds, minutes, hours, day of the week, date, month, and year. Months with fewer than 31 days are automatically adjusted, including leap year corrections.The clock operates in either 24-hour or 12-hour format with AM/PM indication. It features two programmable calendar alarms and a programmable square-wave output. Address and data are transmitted serially via the bidirectional I²C bus. A temperature-compensated voltage reference and comparator monitor VCC status, detect power supply failures, provide a reset output, and automatically switch to backup power when necessary.The RST pin can be used as a manual input to generate a microprocessor reset. In addition to high timing accuracy, the DS3231 includes an integrated digital temperature sensor accessible via the I²C interface (in addition to time data). The temperature sensor accuracy is ±3°C.On-chip control circuitry enables automatic power supply detection and manages switching between primary and backup power (e.g., low-voltage battery). If main power is lost, the device continues to provide accurate time and temperature data without performance degradation. An on-chip reset function can restart the system microprocessor when main power is restored or voltage returns to the acceptable range.1. Other I²C devices can be cascaded. The AT24C32 address can be modified by connecting A0/A1/A2 to ground or VCC. Default address is 0x57. 2. Required battery model: CR2032 — ensures the clock continues running after system power-off. 3. Operating voltage: 3.3–5.5 V 4. RTC chip: High-precision DS3231 5. Clock accuracy: ±2 ppm from 0°C to +40°C; annual error ≈ 1 minute 6. Calendar alarm function included 7. Programmable square-wave output 8. Real-time clock outputs seconds, minutes, hours, day of week, date, month, and year, with leap-year compensation valid through 2100 9. Integrated temperature sensor with ±3°C accuracy 10. Memory chip: AT24C32 (32 Kbit EEPROM) 11. I²C bus interface, up to 400 kHz transmission speed (at 5 V)Wiring instructions (example for Arduino Uno): SCL → A5 SDA → A4 VCC → 5 V GND → GND Note: Minor variations in appearance, color, or silkscreen between batches do not affect functionality. Color: As shown Material: PCB Package contents: 1 × DS3231 module Other items shown are for illustration only and not included. Note: Screen display and lighting conditions may cause slight color variation. Measurement tolerance: ±1–3 cm.