Specification: _x005f_x000D_ Specification: with CR2032 or without CR2032 (optional) _x005f_x000D_ Working voltage: 3.3-5.5V _x005f_x000D_ Clock chip: high-precision clock chip DS3231 _x005f_x000D_ Clock accuracy: within the range of 0-40 ℃, with an accuracy of 2ppm and an annual error of about 1 minute _x005f_x000D_ With 2 calendar alarms _x005f_x000D_ Programmable square wave output _x005f_x000D_ Real-time clock generates seconds, minutes, hours, weeks, dates, months and years, and provides leap year compensation valid until 2100 _x005f_x000D_ The chip comes with a built-in temperature sensor, with an accuracy of ± 3 ℃ _x005f_x000D_ Storage chip: AT24C32 (storage capacity 32K) _x005f_x000D_ IIC bus interface, with a high transmission speed of 400KHz (when the working voltage is 5V) _x005f_x000D_ Can cascade other IIC devices, 24C32 address can be modified by short circuit A0/A1/A2, default address is 0x57 _x005f_x000D_ Size: 38mm/1.49inch (length) * 22mm/0.86inch (width) * 14mm/0.55inch (height) _x005f_x000D_ Weight: 8g _x005f_x000D_ _x005f_x000D_ Wiring instructions (using FOR Arduino r3 as an example): _x005f_x000D_ SCL-A5 _x005f_x000D_ SDA-A4 _x005f_x000D_ VCC-5V _x005f_x000D_ GND-GND _x005f_x000D_ _x005f_x000D_ _x005f_x000D_ Note: _x005f_x000D_ Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! _x005f_x000D_ Please allow 1-2cm measuring deviation due to manual measurement. _x005f_x000D_ _x005f_x000D_ _x005f_x000D_ Included: _x005f_x000D_ 1 x Precision Clock Module 1. High-precision RTC: The DS3231 is an I2C real-time clock (RTC) module that offers high precision at an affordable price. It features an integrated temperature-compensated crystal oscillator (TCXO) and crystal, providing accurate timekeeping capabilities. 2. Comprehensive Timekeeping Functions: The RTC module stores information such as seconds, minutes, hours, day of the week, date, month, and year. It automatically adjusts the month-end date for months with fewer than 31 days, including leap year corrections. The clock can be set to either a 24-hour format or a 12-hour format with AM/PM indication. It also includes two programmable calendar alarms and a configurable square wave output. Address and data transmission occur through the I2C bidirectional bus. 3. Temperature-compensated Voltage Reference: This module utilizes a temperature-compensated voltage reference and comparator circuit to monitor the VCC status. It detects power failures, provides reset outputs, and switches to backup power when necessary. Additionally, the /RST monitoring pin can be used as a manual input to generate microprocessor resets. 4. Additional Features and Flexibility: The DS3231 offers various additional features that enhance system host functionality and provide a wide range of options. It integrates a highly accurate digital temperature sensor that can be accessed via the I2C interface. This sensor provides a ±3°C accuracy. The on-chip control circuitry allows for automatic power detection and manages power switching between the main power source and the backup power (i.e., low-voltage battery). Even in the event of a main power failure, the module continues to provide timekeeping and temperature functions without any performance impact. The on-chip reset function can restart the system microprocessor when the main power is restored or the voltage returns to an acceptable range.