Features: The device contains a battery input end and keeps accurate timing when the main power supply is disconnected. Integrated crystal vibration improves the long-term accuracy of the device and reduces the number of components in the production line.Providers commercial grade and industrial level temperature ranges, using a 16-pin 300 mil SO package. RTC keeps information on seconds, minutes, hours, weeks, dates, months and years.Months less than 31 days will automatically adjust month-end dates, including leap-year revisions. The clock can work in a 24-hour or 12-hour format with/ AM/ PM instructions.Provides two settable calendar alarm clocks and a configurable square-wave output.Address and data are transmitted serial through I2C bidirectional bus. Accurate, temperature-compensated voltage reference and comparator circuits are used to monitor VCC status, detect power failure, provide reset output, and automatically switch to backup power supply if necessary. A very precise digital temperature sensor is integrated inside the device and can be accessed through the I2C * interface.The accuracy of this temperature sensor is ± 3 ° C.The on-chip control circuit can realize the automatic power source detection and manage the power switch between the main power source and the backup power source (i. e. the low-voltage battery).If the main power supply is down, the device can still continue to provide accurate timing and temperature, performance is not affected.The on-chip reset function can be used to restart the system microprocessor when the main power supply is recharged or the voltage value is returned to the allowable range. Specification: Size:38*22*14mm/1.5*0.87*0.55in Weight: 5g/0.18oz Working Voltage:3.3~5.5V Time Accuracy: 2ppm,1min/year(1~40℃) With 2 calendar alarm clock. Programmable square wave output. The real-time clock generates seconds, minutes, hours, weeks, dates, months and years, and provides leap year compensation valid until 2100. Integrated Temperature Sensor Accuracy:+-3℃ Storage Chip: AT24C32(32K Capacity) IIC Bus Port:Max Transmission Speed 400KHz(5V) Concatenable other IIC devices, 24C32 addresses can be modified by short circuit A0/ A1/ A2, the default address is 0x57 Wiring Instruction: SCL-A5 SDA-A4 VCC-5V GND-GND Battery:LIR2032(Not Included) Package List: 1* Module 1、The device contains a battery input end and keeps accurate timing when the main power supply is disconnected. 2、Integrated crystal vibration improves the long?term accuracy of the device and reduces the number of components in the production line.Providers commercial grade and industrial level temperature ranges, using a 16?pin 300 mil SO package. 3、RTC keeps information on seconds, minutes, hours, weeks, dates, months and years.Months less than 31 days will automatically adjust month?end dates, including leap?year revisions. 4、Accurate, temperature?compensated voltage reference and comparator circuits are used to monitor VCC status, detect power failure, provide reset output, and automatically switch to backup power supply if necessary. 5、The clock can work in a 24?hour or 12?hour format with/ AM/ PM instructions.Provides two settable calendar alarm clocks and a configurable square?wave output.Address and data are transmitted serial through I2C bidirectional bus.