ANALOG DEVICES DS1305E+

The DS1305E+ is a serial alarm Real-time Clock provides a full binary coded decimal (BCD) clock calendar that is accessed by a simple serial 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 AM/PM indicator. In addition, 96-byte of NV RAM are provided for data storage. The DS1305 will maintain the time and date, provided the oscillator is enabled, as long as at least one supply is at a valid level. An interface logic power-supply input pin (VCCIF) allows the DS1305 to drive SDO and active-low PF pins to a level that is compatible with the interface logic. This allows an easy interface to 3V logic in mixed supply systems. The DS1305 offers dual-power supplies as well as a battery input pin.