DESCRIPTION
The M48T129Y/V TIMEKEEPER RAM is a 128Kb x 8 non-volatile static RAM and real time clock, with programmable alarms and a watchdog timer.
   
■ INTEGRATED ULTRA LOW POWER SRAM,
    REAL TIME CLOCK, POWER-FAIL CONTROL
    CIRCUIT, BATTERY AND CRYSTAL
■ YEAR 2000 COMPLIANT
■ BCD CODED CENTURY, YEAR, MONTH,
    DAY, DATE, HOURS, MINUTES, and
    SECONDS
■ BATTERY LOW WARNING FLAG
■ AUTOMATIC POWER-FAIL CHIP DESELECT
    and WRITE PROTECTION
■ TWO WRITE PROTECT VOLTAGES:
    (VPFD = Power-fail Deselect Voltage)
    – M48T129Y: 4.2V ≤ VPFD ≤ 4.5V
    – M48T129V: 2.7V ≤ VPFD ≤ 3.0V
■ CONVENTIONAL SRAM OPERATION;
    UNLIMITED WRITE CYCLES
■ SOFTWARE CONTROLLED CLOCK
    CALIBRATION for HIGH ACCURACY
    APPLICATIONS
■ 10 YEARS of DATA RETENTION and CLOCK
    OPERATION in the ABSENCE of POWER
■ SELF CONTAINED BATTERY and CRYSTAL
    in DIP PACKAGE
■ MICROPROCESSOR POWER-ON RESET
    (Valid even during battery back-up mode)
■ PROGRAMMABLE ALARM OUTPUT ACTIVE
    in BATTERY BACK-UP MODE
■ SURFACE MOUNT CHIP SET PACKAGING
    INCLUDES a 44-PIN SOIC and a 32-LEAD
    TSOP (SNAPHAT TOP TO BE ORDERED
    SEPARATELY)
■ SOIC PACKAGE PROVIDES DIRECT
    CONNECTION for a SNAPHAT TOP WHICH
    CONTAINS the BATTERY and CRYSTAL
■ SNAPHAT HOUSING (BATTERY/CRYSTAL)
    IS REPLACEABLE