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