2-Wire� RTC Real Time Clock/Calendar/CPU Supervisor With EEPROM

The X1288 device is a Real Time Clock with Clock calendar, two polled alarms with integrated 32kx8 EEPROM Oscillator compensation, CPU supervisor (POR/LVS and WDT) and battery backup Switch
The Oscillator uses an external, low-cost 32.768kHz crystal. All compensation and trim components are integrated on the chip. This eliminates several external Discrete components and a trim capacitor, saving board area and component cost.
The Real-Time Clock keeps track of time with separate Registers for Hours, Minutes, Seconds and 1/100 of a second. The Calendar has separate Registers for Date, Month, Year and Day-of-week. The calendar is correct through 2099, with Automatic leap year correction.
The powerful Dual Alarms CAN be set to any Clock Calendar value for a match. For instance, every minute, every Tuesday, or 5:23 AM on March 21. The alarms CAN be polled in the Status Register or provide a hardware interrupt (IRQ Pin). There is a repeat mode for the alarms allowing a periodic interrupt.
The PHZ/IRQ pin may be software selected to provide a frequency output of 1 Hz, 100 Hz, or 32,768 Hz.
The X1288 device integrates CPU supervisor func-tions and a Battery Switch There is a Power-On Reset (RESET output) with typically 250 ms delay from poweron. It will also assert RESET when Vcc goes below the specified threshold. The Vtrip threshold is user reprogrammable.
There is a WatchDog Timer (WDT) with 3 selectable time-out periods (0.25s, 0.75s, 1.75s) and a disabled setting. The watchdog activates the RESET pin when it expires
By Intersil Corporation