The DS1308 serial real-time clock (RTC) is a low-power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV RAM. Address and data are transferred serially through an I²C interface. 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 year. The clock operates in either the 24-hour or 12-hour format with an AM/PM indicator. The DS1308 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time and date operation.
Compatible with Crystal ESR Up to 100kΩ Allows a Crystal to be Optimized for Cost and Space
Low-Power Operation Extends Battery Backup Run Time
Low Timekeeping Current of 250nA (typ)
Automatic Power-Fail Detect and Switch Circuitry
Completely Manages All Timekeeping Functions
Real-Time Clock Counts Seconds, Minutes, Hours,Date of the Month, Month, Day of the Week, andYear with Leap-Year Compensation Valid Up to 2400