WED3EG7232S-JD3
PRELIMINARY
DDR SDRAM COMPONENT ELECTRICAL CHARACTERISTICS AND
RECOMMENDED AC OPERATING CONDITIONS
DDR400: V
CC
= V
CCQ
= +2.6V ± 0.1V; DDR333, 266, 200: V
CC
= V
CCQ
= +2.5V ± 0.2V
AC Characteristics
Parameter
Access window of DQs from CK, CK#
CK high-level width
CK low-level width
Clock cycle time
CL=3
CL=2.5
CL=2
DQ and DM input hold time relative to DQS
DQ and DM input setup time relative to DQS
DQ and DM input pulse width (for each input)
Access window of DQS from CK, CK#
DQS input high pulse width
DQS input low pulse width
DQS-DQ skew, DQS to last DQ valid, per group,
per access
Write command to
fi
rst DQS latching transition
DQS falling edge to CK rising - setup time
DQS falling edge from CK rising - hold time
Half clock period
Data-out high-impedance window from CK, CK#
Data-out low-impedance window from CK, CK#
Address and control input hold time (fast slew rate)
Address and control input set-up time (fast slew rate)
Address and control input hold time (slow slew rate)
Address and control input setup time (slow slew rate)
Address and control input pulse width (for each input)
LOAD MODE REGISTER command cycle time
DQ-DQS hold, DQS to
fi
rst DQ to go non-valid, per
access
Data hold skew factor
ACTIVE to PRECHARGE command
ACTIVE to READ with Auto precharge command
ACTIVE to ACTIVE/AUTO REFRESH command period
AUTO REFRESH command period
Symbol
t
AC
t
CH
t
CL
t
CK
(3)
t
CK
(2.5)
t
CK
(2)
t
DH
t
DS
t
DIPW
t
DQSCK
t
DQSH
t
DQSL
t
DQSQ
t
DQSS
t
DSS
t
DSH
t
HP
t
HZ
t
LZ
t
IHf
t
ISf
t
IHs
t
ISs
t
IPW
t
MRD
t
QH
t
QHS
t
RAS
t
RAP
t
RC
t
RFC
40
15
55
70
-0.70
0.60
0.60
0.60
0.60
2.2
10
t
HP
-t
QHS
0.50
70,000
42
15
60
72
0.72
0.2
0.2
t
CH
, t
CL
+0.70
-0.70
0.75
0.75
0.80
0.80
2.2
12
t
HP
-t
QHS
0.55
70,000
40
15
60
75
Min
-0.70
0.45
0.45
5
6
7.5
0.40
0.40
1.75
-0.60
0.35
0.35
0.40
1.28
0.75
0.2
0.2
t
CH
, t
CL
+0.70
-0.75
0.90
0.90
1
1
2.2
15
t
HP
-t
QHS
0.75
120,000
45
20
65
75
+0.60
403
Max
+0.70
0.55
0.55
7.5
13
13
6
7.5
0.45
0.45
1.75
-0.60
0.35
0.35
0.45
1.25
0.75
0.2
0.2
t
CH
, t
CL
+0.75
-0.75
0.90
0.90
1
1
2.2
15
t
HP
-t
QHS
0.75
120,000
+0.60
13
13
7.5
7.5
0.5
0.5
1.75
-0.75
0.35
0.35
0.5
1.25
0.75
0.2
0.2
t
CH
, t
CL
+0.75
+0.75
13
13
7.5
10
0.5
0.5
1.75
-0.75
0.35
0.35
0.5
1.25
+0.75
13
13
Min
-0.70
0.45
0.45
335
Max
+0.70
0.55
0.55
262/265
Min
-0.75
0.45
0.45
Max
+0.75
0.55
0.55
Min
-0.75
0.45
0.45
202
Max
+0.75
0.55
0.55
Units
ns
t
CK
t
CK
ns
ns
ns
ns
ns
ns
ns
t
CK
t
CK
ns
t
CK
t
CK
t
CK
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
21
15
13,14
18
8,19
8,20
6
6
6
6
13,14
16
16
22
22
22
14,17
14,17
17
Notes
June 2006
Rev. 6
7
White Electronic Designs Corporation • (602) 437-1520 • www.wedc.com
WEDC [ WHITE ELECTRONIC DESIGNS CORPORATION ]
