CY621472G30-45ZSXAT is a 4-Mbit (256K × 16) CMOS SRAM with embedded ECC for single-bit error correction. It operates from 2.2 V to 3.6 V, supports 45 ns access, and targets Automotive-A (-40°C to +85°C). Standby current is 3.5 µA typical. TTL-compatible I/O and byte control (BHE/BLE) support 8-bit accesses; byte power-down forces standby when both bytes are disabled. 44-pin TSOP II, dual chip enable, tape-and-reel.