PRELIMINARY DATA SHEET
2GB Registered DDR SDRAM DIMM
EBD21RD4ABNA (256M words
×
72 bits, 2 Banks)
Description
The EBD21RD4ABNA is a 256M words
×
72 bits, 2
bank Double Data Rate (DDR) SDRAM Module,
mounted 36 pieces of DDR SDRAM sealed in TCP
package. 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-bit 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 register,
the on-chip Delay Locked Loop (DLL) can be set
enable or disable. This module provides high density
mounting without utilizing surface mount technology.
Decoupling capacitors are mounted beside each TCP
on the module board.
Note: Do not push the cover or drop the modules in
order to avoid mechanical defects, which may
result in electrical defects.
Features
•
184-pin socket type dual in line memory module
(DIMM)
PCB height: 30.48mm
Lead pitch: 1.27mm
•
2.5V power supply
•
Data rate: 266Mbps/200Mbps (max.)
•
2.5 V (SSTL_2 compatible) I/O
•
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 and outputs are synchronized with DQS
•
4 internal banks for concurrent operation
(Component)
•
DQS is edge aligned with data for READs; center
aligned with data for WRITEs
•
Differential clock inputs (CK and /CK)
•
LL aligns DQ and DQS transitions with CK
transitions
•
Commands entered on each positive CK edge; data
referenced to both edges of DQS
•
Auto precharge option for each burst access
•
Programmable burst length: 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
•
1 piece of PLL clock driver, 1 piece of register driver
and 1 piece of serial EEPROM (2k bits EEPROM) for
Presence Detect (PD)
Document No. E0273E20 (Ver. 2.0)
Date Published
Aug
2002 (K) Japan
URL: http://www.elpida.com
Elpida
Memory, Inc. 2002
EBD21RD4ABNA
Pin Description
Pin name
A0 to A12
BA0, BA1
DQ0 to DQ63
CB0 to CB7
/RAS
/CAS
/WE
/CS0, /CS1
CKE0, CKE1
CK0
/CK0
DQS0 to DQS8
DM0 to DM8/DQS9 to DQS17
SCL
SDA
SA0 to SA2
VDD
VDDQ
VDDSPD
VREF
VSS
VDDID
/RESET
NC
Function
Address input
Row address
Column address
A0 to A12
A0 to A9, A11, A12
Bank select address
Data input/output
Check bit (Data input/output)
Row address strobe command
Column address strobe command
Write enable
Chip select
Clock enable
Clock input
Differential clock input
Input and output data strobe
Input and output data strobe
Clock input for serial PD
Data input/output for serial PD
Serial address input
Power for internal circuit
Power for DQ circuit
Power for serial EEPROM
Input reference voltage
Ground
VDD identification flag
Reset pin (forces register inputs low)
No connection
Preliminary Data Sheet E0273E20 (Ver. 2.0)
4
EBD21RD4ABNA
Serial PD Matrix*
Byte No.
0
1
2
3
4
5
6
7
8
9
1
Function described
Number of bytes utilized by module
manufacturer
Total number of bytes in serial PD
device
Memory type
Number of row address
Number of column address
Number of DIMM banks
Module data width
Module data width continuation
Bit7
1
0
0
0
0
0
0
0
Bit6
0
0
0
0
0
0
1
0
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
1
0
0
0
1
0
1
Bit5 Bit4
0
0
0
0
0
0
0
0
0
1
1
1
0
0
0
0
0
0
0
0
0
0
0
1
0
1
1
1
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
1
0
0
0
1
1
1
Bit3
0
1
0
1
1
0
1
0
0
0
0
0
0
0
0
0
0
0
1
0
1
0
0
0
0
0
0
0
0
0
0
0
1
0
Bit2
0
0
1
1
1
0
0
0
1
1
0
1
0
0
0
1
1
0
1
1
1
0
0
1
0
1
0
1
0
0
0
0
1
0
Bit1 Bit0
0
0
1
0
0
1
0
0
0
0
0
0
0
1
1
0
0
0
1
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
1
0
1
0
0
0
0
0
1
0
0
0
1
0
0
0
1
0
1
0
0
0
0
0
0
Hex value
80H
08H
07H
0DH
0CH
02H
48H
00H
04H
75H
A0H
75H
80H
02H
82H
04H
04H
01H
0EH
04H
0CH
01H
02H
26H
C0H
75H
A0H
75H
80H
00H
00H
50H
3CH
50H
Comments
128
256 byte
SDRAM DDR
13
12
2
72 bits
0 (+)
SSTL 2.5V
CL = 2.5*
3
Voltage interface level of this assembly 0
DDR SDRAM cycle time, CL = X
-7A, -7B
-10
SDRAM access from clock (tAC)
-7A, -7B
-10
0
1
0
1
0
1
0
0
0
0
0
0
0
0
0
1
10
0.75ns*
3
0.8ns*
3
ECC
7.8 µs
Self refresh
×
4
×
4
1 CLK
2, 4, 8
4
2, 2.5
0
1
Registered
± 0.2V
CL = 2*
3
11
12
13
14
15
16
17
18
19
20
21
22
23
DIMM configuration type
Refresh rate/type
Primary SDRAM width
Error checking SDRAM width
SDRAM device attributes:
Minimum clock delay back-to-back
column access
SDRAM device attributes:
Burst length supported
SDRAM device attributes: Number of
banks on SDRAM device
SDRAM device attributes:
/CAS latency
SDRAM device attributes:
/CS latency
SDRAM device attributes:
/WE latency
SDRAM module attributes
SDRAM device attributes: General
Minimum clock cycle time at CLX - 0.5
0
-7A
-7B, -10
1
Maximum data access time (tAC) from
clock at CLX - 0.5
0
-7A, -7B
-10
1
0
24
0.75ns*
3
0.8ns*
3
25
26
27
28
29
Minimum clock cycle time at CLX - 1
Maximum data access time (tAC) from
0
clock at CLX - 1
Minimum row precharge time (tRP)
Minimum row active to row active
delay (tRRD)
Minimum /RAS to /CAS delay (tRCD)
0
0
0
20ns
15ns
20ns
Preliminary Data Sheet E0273E20 (Ver. 2.0)
5
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