Internet Data Sheet
HY[B/I]18T256[40/80/16]0B[C/F](L)
256-Mbit Double-Data-Rate-Two SDRAM
1
Overview
This chapter gives an overview of the 256-Mbit Double-Data-Rate-Two SDRAM product family and describes its main
characteristics.
1.1
Features
The 256-Mbit Double-Data-Rate-Two SDRAM offers the following key features:
• Off-Chip-Driver impedance adjustment (OCD) and
• 1.8 V
±
0.1 V Power Supply
1.8 V
±
0.1 V (SSTL_18) compatible I/O
On-Die-Termination (ODT) for better signal quality
• DRAM organizations with 4, 8 and 16 data in/outputs
• Auto-Precharge operation for read and write bursts
• Double Data Rate architecture: two data transfers per
• Auto-Refresh, Self-Refresh and power saving Power-
clock cycle four internal banks for concurrent operation
Down modes
• Programmable CAS Latency: 3, 4, 5 and 6
• Average Refresh Period 7.8
μs
at a
T
CASE
lower than
• Programmable Burst Length: 4 and 8
85 °C, 3.9
μs
between 85 °C and 95 °C
• Differential clock inputs (CK and CK)
• Programmable self refresh rate via EMRS2 setting
• Programmable partial array refresh via EMRS2 settings
• Bi-directional, differential data strobes (DQS and DQS) are
transmitted / received with data. Edge aligned with read
• DCC enabling via EMRS2 setting
• Full and reduced Strength Data-Output Drivers
data and center-aligned with write data.
• DLL aligns DQ and DQS transitions with clock
• 1K page size
• Packages: P(G)-TFBGA-60 for
×4
&
×8
components,
• DQS can be disabled for single-ended data strobe
operation
P(G)-TFBGA-84 for
×16
components
• RoHS Compliant Products
1)
• Commands entered on each positive clock edge, data and
data mask are referenced to both edges of DQS
• All Speed grades faster than DDR2–400 comply with
DDR2–400 timing specifications when run at a clock rate
• Data masks (DM) for write data
• Posted CAS by programmable additive latency for better
of 200 MHz.
command and data bus efficiency
TABLE 1
Performance Tables for –25(F)
Product Type Speed Code
Speed Grade
Max. Clock Frequency
@CL6
@CL5
@CL4
@CL3
Min. RAS-CAS-Delay
Min. Row Precharge Time
Min. Row Active Time
Min. Row Cycle Time
–25F
DDR2–800D 5–5–5
–2.5
DDR2–800E 6–6–6
400
333
266
200
15
15
45
60
Unit
—
MHz
MHz
MHz
MHz
ns
ns
ns
ns
f
CK6
f
CK5
f
CK4
f
CK3
t
RCD
t
RP
t
RAS
t
RC
400
400
266
200
12.5
12.5
45
57.5
1) RoHS Compliant Product: Restriction of the use of certain hazardous substances (RoHS) in electrical and electronic equipment as defined
in the directive 2002/95/EC issued by the European Parliament and of the Council of 27 January 2003. These substances include mercury,
lead, cadmium, hexavalent chromium, polybrominated biphenyls and polybrominated biphenyl ethers.
Rev. 1.11, 2007-07
11172006-LBIU-F1TN
3
QIMONDA [ QIMONDA AG ]
