
Elpida Memory, Inc
Features
• Double-data-rate architecture; two data transfers per clock cycle
• The high-speed data transfer is realized by the 4 bits prefetch pipelined architecture
• Bi-directional differential data strobe (DQS and /DQS) is transmitted/received with data for capturing data at the receiver
• 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
• Posted /CAS by programmable additive latency for better command and data bus efficiency
• Off-Chip-Driver Impedance Adjustment and On-Die Termination for better signal quality
• /DQS can be disabled for single-ended Data Strobe operation
Specifications
• Density: 1GB
• Organization
- 128M words × 64 bits, 1 rank
• Mounting 8 pieces of 1G bits DDR2 SDRAM sealed in FBGA
• Package: 240-pin socket type dual in line memory module (DIMM)
- PCB height: 30.0mm
- Lead pitch: 1.0mm
- Lead-free (RoHS compliant)
• Power supply: VDD = 1.8V ± 0.1V
• Data rate: 800Mbps/667Mbps (max.)
• Eight internal banks for concurrent operation (components)
• Interface: SSTL_18
• Burst lengths (BL): 4, 8
• /CAS Latency (CL): 3, 4, 5, 6
• Precharge: auto precharge option for each burst access
• Refresh: auto-refresh, self-refresh
• Refresh cycles: 8192 cycles/64ms
- Average refresh period
7.8µs at 0°C ≤ TC ≤ +85°C
3.9µs at +85°C < TC ≤ +95°C
• Operating case temperature range
- TC = 0°C to +95°C