DS1307 serial real-time clock (RTC) is a low power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV SRAM. address and data are transferred serially through an I2C, bidirectional bus. The 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.
DS1307 RTC IC has a built-in power sense circuit that detects power failures and automatically switches to the backup supply. Timekeeping operation continues while the part operates from the backup supply.
- Completely manages all timekeeping functions
- Counts seconds, minutes, hours, date of the month, month, day of the week, and year with leap-year compensation valid up to 2100.
- 56-byte, battery-backed, general-purpose RAM with unlimited writes.
- Programmable square wave output signal.
- Simple serial port interfaces to most microcontrollers
- I2C serial interface.
- Low power operation extends battery backup run time
- Consumes less than 500nA in battery-backup mode with oscillator running
- Automatic power-fail detect and switch circuitry.
- Supply voltage (Vcc): 4.5V to 5.5V
- Logic 1 input: 2.2V to Vcc+0.3V
- Logic 0 input: -0.3V to 0.8V
- Maximum SCL clock frequency: 100kHz