PRELIMINARY DATA SHEET
256M bits DDR SDRAM
EDD2516AKTA (16M words × 16 bits)
Description
Pin Configurations
The EDD2516AKTA is a 256M bits Double Data Rate
(DDR) SDRAM organized as 4,194,304 words × 16 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 register,
the on-chip Delay Locked Loop (DLL) can be set
enable or disable. It is packaged in 66-pin plastic
TSOP (II).
/xxx indicates active low signal.
66-pin Plastic TSOP(II)
VDD
DQ0
VDDQ
DQ1
DQ2
VSSQ
DQ3
DQ4
VDDQ
DQ5
DQ6
VSSQ
DQ7
NC
VDDQ
LDQS
NC
VDD
NC
LDM
/WE
/CAS
/RAS
/CS
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
VSS
1
2
3
4
5
6
7
8
DQ15
VSSQ
DQ14
DQ13
VDDQ
DQ12
DQ11
VSSQ
DQ10
DQ9
VDDQ
DQ8
NC
VSSQ
UDQS
NC
VREF
VSS
UDM
/CK
CK
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
Features
• 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
CKE
NC
A12
A11
A9
NC
BA0
BA1
• 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
A10(AP) 28
A0 29
39 A8
38 A7
37 A6
36 A5
35 A4
34 VSS
A1 30
A2 31
A3 32
VDD 33
• Differential clock inputs (CK and /CK)
• DLL aligns DQ and DQS transitions with CK
transitions
(Top view)
• Commands entered on each positive CK edge; data
and data mask referenced to both edges of DQS
A0 to A12
BA0, BA1
Address input
Bank select address
• Data mask (DM) for write data
• Auto precharge option for each burst access
• SSTL_2 compatible I/O
• Programmable burst length (BL): 2, 4, 8
• Programmable /CAS latency (CL): 2, 2.5
• Programmable output driver strength: normal/weak
• Refresh cycles: 8192 refresh cycles/64ms
⎯ 7.8μs maximum average periodic refresh interval
• 2 variations of refresh
DQ0 to DQ15 Data-input/output
UDQS/LDQS Input and output data strobe
/CS
/RAS
/CAS
/WE
UDM/LDM
CK
Chip select
Row address strobe command
Column address strobe command
Write enable
Input mask
Clock input
/CK
CKE
Differential clock input
Clock enable
VREF
VDD
VSS
VDDQ
VSSQ
NC
Input reference voltage
Power for internal circuit
Ground for internal circuit
Power for DQ circuit
Ground for DQ circuit
No connection
⎯ Auto refresh
⎯ Self refresh
Document No. E0303E40 (Ver. 4.0)
This product became EOL in March, 2007.
Date Published February 2005 (K) Japan
Printed in Japan
URL: http://www.elpida.com
©Elpida Memory, Inc. 2002-2005