FEATURES

? Ideal for EISA bus PCs

? Functionally compatible with MC146818 in 32 KHz mode

? Totally nonvolatile with over 10 years of operation in the absence of power

? Self-contained subsystem includes lithium, quartz, and support circuitry

? Counts seconds, minutes, hours, day of the week, date, month, and year with leap year compensation

? Binary or BCD representations of time, calendar, and alarm

? 12- or 24-hour clock with AM and PM in 12-hour mode

? Daylight Savings Time option

? Interfaced with software as 64 register/RAM locations plus 8K x 8 of static RAM

– 14 bytes of clock and control registers

– 50 bytes of general and control registers

– Separate 8K x 8 nonvolatile SRAM

? Programmable square wave output signal

? Bus-compatible interrupt signals (IRQ)

? Three interrupts are separately software-maskable and testable:

– Time-of-day alarm once/second to once/day

– Periodic rates from 122 μs to 500 ms

– End-of-clock update cycle

? 28-pin JEDEC footprint

? Available as chip (DS1495/DS1495S) or stand alone module with embedded lithium battery and crystal (DS1497)