Real Time Clock (RTC) IC Clock/Calendar I²C, 2-Wire Serial 16-SOIC (0.295", 7.50mm Width)
The DS1339U-33+T&R is an I2C serial real time clock (RTC) in 8 pin µSOP package. It is a low power clock/calendar with two programmable time of day alarms and programmable square wave output. Address and data are transferred serially through an I2C bus. It has operating voltage of 3.3V. The clock/calendar 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 leap year compensation valid up to 2100. The clock operates in either 24hour or 12hour 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 while maintaining time, date and alarm operation. It has SCL clock frequency of 400KHz in fast mode and 100KHz in standard mode. The device is used in utility meter, vending machine, thermostat, modem, router, switch and server.