
STMicroelectronics
DESCRIPTION
The M48T39Y TIMEKEEPER® RAM is a non-volatile 262,144 bit static RAM and real time clock organized as 32,768 words by 8 bits. System integration features include Programmable Alarms, Watchdog Timer and Interval Timer. The special 32-pin DIP package provides a highly integrated battery back-up memory and real time clock solution.
■ INTEGRATED ULTRA LOW POWER SRAM, REAL TIME CLOCK, POWER-FAIL CONTROL CIRCUIT, BATTERY and CRYSTAL
■ BCD CODED YEAR, MONTH, DAY, DATE, HOURS, MINUTES and SECONDS
■ AUTOMATIC POWER-FAIL CHIP DESELECT and WRITE PROTECTION
■ WRITE PROTECT VOLTAGE (VPFD = Power-fail Deselect Voltage): – M48T39Y: 4.20V ≤ VPFD ≤ 4.50V
■ PROGRAMMABLE INTERRUPTS and SQUARE WAVE OUTPUT
■ WATCHDOG TIMER RESTARTS on OUT-OF-CONTROL PROCESSOR
■ CLOCK ACCURACY IS BETTER THAN ±1 MINUTE per MONTH at 25°C
■ 10 YEARS of DATA RETENTION and CLOCK OPERATION in the ABSENCE of POWER
■ SELF-CONTAINED BATTERY and CRYSTAL in DIP PACKAGE
■ PROGRAMMABLE ALARM OUTPUT ACTIVE in the BATTERY BACK-UP MODE
■ PIN and FUNCTION COMPATIBLE with DS1386