CY7C2644KV18-333BZXI is not listed in this datasheet; the closest available variant is CYRS2644KV18-250GCMB, a 144-Mbit (4M × 36) QDR® II+ synchronous pipelined burst SRAM. It uses separate read and write ports with DDR interfaces (250 MHz clock, 500 MHz data transfer) and 2-cycle read latency with DOFF high (1-cycle QDR I mode with DOFF low). 1.8 V core and 1.4 V to VDD I/O support high-speed systems.