
STMicroelectronics
SUMMARY DESCRIPTION
The M48T35AY/V TIMEKEEPER® RAM is a 32Kb x 8 non-volatile static RAM and real time clock. The monolithic chip is available in two special packages to provide a highly integrated battery backed-up memory and real time clock solution. The M48T35AY/V is a non-volatile pin and func
tion equivalent to any JEDEC standard 32Kb x 8 SRAM. It also easily fits into many ROM, EPROM,
and EEPROM sockets, providing the non-volatility of PROMs without any requirement for special
WRITE timing or limitations on the number of WRITEs that can be performed.
FEATURES SUMMARY
■ INTEGRATED, ULTRA LOW POWER SRAM,REAL TIME CLOCK, POWER-FAIL CONTROL CIRCUIT AND BATTERY
■ BYTEWIDE™ RAM-LIKE CLOCK ACCESS
■ BCD CODED YEAR, MONTH, DAY, DATE,HOURS, MINUTES, AND SECONDS
■ FREQUENCY TEST OUTPUT FOR REAL TIME CLOCK
■ AUTOMATIC POWER-FAIL CHIP DESELECT AND WRITE PROTECTION
■ WRITE PROTECT VOLTAGES (VPFD= Power-fail Deselect Voltage):
– M48T35AY: VCC= 4.5 to 5.5V
4.2V ≤ VPFD ≤4.5V
– M48T35AV: VCC= 3.0 to 3.6V
2.7V ≤ VPFD ≤ 3.0V
■ SELF-CONTAINED BATTERY AND CRYSTAL IN THE CAPHAT™ DIP PACKAGE
■ SOIC PACKAGE PROVIDES DIRECT CONNECTION FOR A SNAPHAT® HOUSING CONTAINING THE BATTERY AND CRYSTAL
■ SNAPHAT® HOUSING (BATTERY AND CRYSTAL) IS REPLACEABLE
■ PIN AND FUNCTION COMPATIBLE WITH JEDEC STANDARD 32Kb x8 SRAMs