GENERAL DESCRIPTION

The DS1339 serial real-time clock (RTC) is a low power clock/date device with two programmable time-of-day alarms and a programmable square-wave output. Address and data are transferred serially through an I2C bus. The clock/date provides seconds, minutes, hours, day, date, month, and year information. The date at the end of the month 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. The DS1339 has a built-in power sense circuit that detects power failures and automatically switches to the backup supply, maintaining time, date, and alarm operation.

FEATURES

◾ Real-Time Clock (RTC) Counts Seconds, Minutes, Hours, Day, Date, Month, and Year with LeapYear Compensation Valid Up to 2100

◾ Available in a Surface-Mount Package with an Integrated Crystal (DS1339C)

◾ I2C Serial Interface

◾ Two Time-of-Day Alarms

◾ Programmable Square-Wave Output

◾ Oscillator Stop Flag

◾ Automatic Power-Fail Detect and Switch Circuitry

◾ Trickle-Charge Capability

◾ Underwriters Laboratories (UL) Recognized

APPLICATIONS

    Handhelds (GPS, POS Terminals)

    Consumer Electronics (Set-Top Box, Digital Recording, Network Appliance)

    Office Equipment (Fax/Printers, Copier)

    Medical (Glucometer, Medicine Dispenser)

    Telecommunications (Routers, Switches, Servers)

    Other (Utility Meter, Vending Machine, Thermostat, Modem)