X1228 pdf datasheet (Real Time

Real Time Clock/Calendar/CPU
Supervisor with EEPROM
FEATURES
• Real Time Clock/Calendar
—Tracks Time in Hours, Minutes, and Seconds
—Day of the Week, Day, Month, and Year
• 2 Polled Alarms (Non-volatile)
—Settable on the Second, Minute, Hour, Day of the
Week, Day, or Month
—Repeat Mode (periodic interrupts)
• Oscillator Compensation on Chip
—Internal Feedback Resistor and Compensation
Capacitors
—64 Position Digitally Controlled Trim Capacitor
—6 Digital Frequency Adjustment Settings to
±30ppm
• CPU Supervisor Functions
—Power-On Reset, Low Voltage Sense
—Watchdog Timer (SW Selectable: 0.25s, 0.75s,
1.75s, off)
• Battery Switch or Super Cap Input
• 512 x 8 Bits of EEPROM
—64-Byte Page Write Mode
—8 Modes of Block Lock™ Protection
—Single Byte Write Capability
• High Reliability
—Data Retention: 100 Years
—Endurance: 100,000 Cycles Per Byte