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DATASHEET
ISL1221
Low Power RTC with Battery Backed SRAM and Event Detection
FN6316 Rev 1.00 July 15, 2010
The ISL1221 device is a low power real time clock with Event Detect and Time Stamp function, timing and crystal compensation, clock/calendar, power fail indicator, periodic or polled alarm, intelligent battery backup switching with separate FOUT output and 2 Bytes of battery-backed user SRAM.
The oscillator uses an external, low-cost 32.768kHz crystal. The real time clock tracks time with separate registers for hours, minutes, and seconds. The device has calendar registers for date, month, year and day of the week. The calendar is accurate through 2099, with automatic leap year correction.