Description
The EDD5104AB is a 512M bits Double Data Rate (DDR) SDRAM organized as 33,554,432 words × 4 bits × 4 banks. The EDD5108AB is a 512M bits DDR SDRAM organized as 16,777,216 words × 8 bits × 4 banks. Read and write operations are performed at the cross points of the CK and the /CK. This high-speed data transfer is realized by the 2 bits prefetch-pipelined architecture. Data strobe (DQS) both for read and write are available for high speed and reliable data bus design. By setting extended mode resistor, the on-chip Delay Locked Loop (DLL) can be set enable or disable. They are packaged in standard 66-pin plastic TSOP (II)10.16mm(400).

FEATUREs
• 2.5 V power supply: VDDQ = 2.5V ± 0.2V : VDD = 2.5V ± 0.2V
• Data Rate: 333Mbps/266Mbps (max.)
• Double Data Rate architecture; two data transfers per clock cycle
• Bi-directional, data strobe (DQS) is transmitted/received with data, to be used in capturing data at the receiver
• Data inputs, outputs, and DM are synchronized with DQS
• 4 internal banks for concurrent operation
• DQS is edge aligned with data for READs; center aligned with data for WRITEs
• Differential clock inputs (CK and /CK)
• DLL aligns DQ and DQS transitions with CK transitions
• Commands entered on each positive CK edge; data and data mask referenced to both edges of DQS
• Data mask (DM) for write data
• Auto precharge option for each burst access
• 2.5 V (SSTL_2 compatible) I/O
• Programmable burst length (BL): 2, 4, 8
• Programmable /CAS latency (CL): 2, 2.5
• Refresh cycles: 8192 refresh cycles/64ms
    - 7.8µs maximum average periodic refresh interval
• 2 variations of refresh
    - Auto refresh
    - Self refresh