Alliance Memory AS4C128M16D2A-25BCN, SDRAM 2Gbit Surface Mount, 400MHz, 1.7 V to 1.9 V, 84-Pin FBGA

The Alliance Memory 2Gb DDR2 is a high-speed CMOS Double-Data- Rate-Two (DDR2), synchronous dynamic random - access memory (SDRAM) containing 2048 Mbits in a 16- bit wide data I/Os. It is internally configured as a 8-bank DRAM, 8 banks x 16Mb addresses x 16 I/Os. The device is designed to comply with DDR2 DRAM key features such as posted CAS# with additive latency, Write latency = Read latency -1, Off-Chip Driver (OCD) impedance adjustment, and On Die Termination(ODT).

8 internal banks for concurrent operation
4-bit prefetch architecture
Internal pipeline architecture
Precharge & active power down
Programmable Mode & Extended Mode registers