ST M48Z512A M48Z512AY M48Z512AV 4 Mbit (512 Kbit x 8) ZEROPOWER SRAM handbook
Datasheet
This document provides information on the features and characteristics of M48Z512A/Y/V ZEROPOWER® RAM, including integrated ultra low power SRAM, power-fail control circuit, and battery, unlimited WRITE cycles, 10 years of data retention in the absence of power, automatic power-fail chip deselect and WRITE protection, etc.