The I2C real time clock module (HCMODU0094) is based on the Maxim high accuracy DS3231 real time clock controller. Using an internal temperature compensation crystal oscillator this RTC IC is able to provide extremely high accurate time keeping. The module includes an on-board battery backup and maintains accurate timekeeping when main power to...

The DS1302 timekeeping chip contains a real-time clock/calendar and 31 bytes of static RAM. It communicates with a microprocessor via a simple serial interface. The real-time clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is automatically adjusted for months with fewer than 31 days, including corrections for leap...

High quality DS1307 using the I2C real time clock chip.