M48T201VMH Datasheet - STMicroelectronics

DESCRIPTION
The M48T201Y/V are self-contained devices that include a real time clock (RTC), programmable alarms, a watchdog timer, and a square wave output which provides control of up to 512K x 8 of external low-power static RAM. Access to all RTC functions and the external RAM is the same as conventional bytewide SRAM. The 16 TIMEKEEPER® registers offer year, month, date, day, hour, minute, second, calibration, alarm, century, watchdog, and square wave output data. Externally attached static RAMs are controlled by the M48T201Y/V via the GCON and ECON signals.

FEATURES SUMMARY
■ CONVERTS LOW POWER SRAM INTO NVRAMs
■ YEAR 2000 COMPLIANT
■ BATTERY LOW FLAG
■ INTEGRATED REAL TIME CLOCK, POWERFAIL CONTROL CIRCUIT, BATTERY AND CRYSTAL
■ WATCHDOG TIMER
■ CHOICE OF WRITE PROTECT VOLTAGES (VPFD = Power-fail Deselect Voltage):
   – M48T201Y: VCC = 4.5 to 5.5V
      4.1V ≤ VPFD ≤ 4.5V
   – M48T201V: VCC = 3.0 to 3.6V
      2.7V ≤ VPFD ≤ 3.0V
■ MICROPROCESSOR POWER-ON RESET
   (Valid even during battery back-up mode.)
■ PROGRAMMABLE ALARM OUTPUT ACTIVE IN THE BATTERY BACKED-UP MODE
■ PACKAGING INCLUDES A 44-LEAD SOIC AND SNAPHAT® TOP (to be ordered separately)
■ SOIC PACKAGE PROVIDES DIRECT CONNECTION FOR A SNAPHAT® TOP WHICH CONTAINS THE BATTERY AND CRYSTAL