IDT 70V631S12BC 4Mb SDR RAM, 18b Words, 3.15-3.45V, 0-70°C, LBGA
SRAM Chip Async Dual 3.3V 4.5M-Bit 256K x 18 12ns 256-Pin CABGA
SRAM Chip Async Dual 3.3V 4.5M-Bit 256K x 18 12ns 256-Pin CABGA T/R