DESCRIPTION
The M48Z512A/512AY ZEROPOWER® RAM is a non-volatile 4,194,304 bit Static RAM organized as 524,288 words by 8 bits. The device combines an internal lithium battery, a CMOS SRAM and a control circuit in a plastic 32 pin DIP Module. For surface mount environments ST provides a Chip Set solution consisting of a 28 pin 330mil SOIC NVRAM Supervisor (M40Z300) and a 32 pin TSOP Type II (10 x 20mm) LPSRAM (M68Z512) packages.
The unique design allows the SNAPHAT battery package to be mounted on top of the SOIC pack age after the completion of the surface mount pro cess. Insertion of the SNAPHAT housing after reflow prevents potential battery damage due to the high temperatures required for device surface mounting. The SNAPHAT housing is keyed to pre vent reverse insertion.
The SNAPHAT battery package is shipped sepa rately in plastic anti-static tubes or in Tape & Reel form. The part number is ”M4Zxx-BR00SH1”.

■ INTEGRATED LOW POWER SRAM, POWER-FAIL CONTROL CIRCUIT and BATTERY
■ CONVENTIONAL SRAM OPERATION; UNLIMITED WRITE CYCLES
■ 10 YEARS of DATA RETENTION in the ABSENCE of POWER
■ AUTOMATIC POWER-FAIL CHIP DESELECT and WRITE PROTECTION
■ WRITE PROTECT VOLTAGES
   (VPFD = Power-fail Deselect Voltage):
   – M48Z512A: 4.50V ≤ VPFD ≤ 4.75V
   – M48Z512AY: 4.20V ≤ VPFD ≤ 4.50V
■ BATTERY INTERNALLY ISOLATED UNTIL POWER IS APPLIED
■ PIN and FUNCTION COMPATIBLE with JEDEC STANDARD 512K x 8 SRAMs
■ SURFACE MOUNT CHIP SET PACKAGING INCLUDES a 28-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
■ SNAPHAT HOUSING (BATTERY) IS REPLACEABLE