This document is the product manual of IDT71V2556/58 3.3V high-speed synchronous SRAM devices. It introduces the features and characteristics of the devices, including 128K x 36, 256K x 18 memory configurations, 200 MHz high performance system clock speed, ZBTTM feature, single R/W control pin, 4-word burst capability, individual byte write control, three chip enables, 3.3V power supply, 2.5V I/O supply, JEDEC standard 100-pin plastic thin quad flatpack (TQFP), 119 ball grid array (BGA) and 165 fine pitch ball grid array (fBGA).