The ISL1208 device is a low power real time clock withtiming and crystal compensation, clock/calendar, power failindicator, periodic or polled alarm, intelligent battery backupswitching and battery-backed user SRAM.The oscillator uses an external, low-cost 32.768kHz crystal.The real time clock tracks time with separate registers forhours, minutes, and seconds. The device has calendarregisters for date, month, year and day of the week. Thecalendar is accurate through 2099, with automatic leap yearcorrection.