Real time clocks rtc, as the name recommends are clock modules. The ds1307 real time clock rtc ic is an 8 pin device using an i2c interface. The ds1307 is a low power clock calendar with 56 bytes of battery backup sram. The clock calendar provides seconds, minutes, hours, day, date, month and year qualified data. The end date of each month is automatically adjusted, especially for months with less than 31 days. They are available as integrated circuits and supervise timing like a clock and also operate date like a calendar. The main advantage of rtc is that they have an arrangement of battery back up which keeps the clock/calendar running even if there is a power failure. An exceptionally little current is required for keeping the rtc animated. We can find these rtcs in many applications like embedded systems and computer motherboards, etc.