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Table 11: AC Operating Specifications and Conditions (Continued)
Not all speed grades listed may be supported for this device; refer to the title page for speeds supported; Notes: 1–5 apply to the entire table;
VDDQ = +1.8V ±0.1V, VDD = +1.8V ±0.1V
AC Characteristics
-187E
-25E
-25
-3E
-3
-37E
-5E
Units Notes
Parameter
Symbol
Min
Max
Min Max Min Max Min Max Min Max Min Max Min Max
Command
and
Address
Internal READ-to-
PRECHARGE delay
tRTP
7.5
–
7.5
–
7.5
–
7.5
–
7.5
–
7.5
–
7.5
–
ns
CAS#-to-CAS#
delay
tCCD
2
–
2
–
2
–
2
–
2
–
2
–
2
–
tCK
Write recovery time
tWR
15
–
15
–
15
–
15
–
15
–
15
–
15
–
ns
Write AP recovery
+ precharge time
tDAL
tWR +
tRP
–
tWR +
tRP
–
tWR +
tRP
–
tWR +
tRP
–
tWR +
tRP
–
tWR +
tRP
–
tWR +
tRP
–
ns
Internal WRITE-to-
READ delay
tWTR
7.5
–
7.5
–
7.5
–
7.5
–
7.5
–
7.5
–
10
–
ns
LOAD MODE cycle
time
tMRD
2
–
2
–
2
–
2
–
2
–
2
–
2
–
tCK
Refresh
REFRESH-
to-
ACTIVATE
or to
-REFRESH
interval
256Mb
tRFC
75
–
75
–
75
–
75
–
75
–
75
–
75
–
ns
512Mb
105
–
105
–
105
–
105
–
105
–
105
–
105
–
1Gb
127.5
–
127.5
–
127.5
–
127.5
–
127.5
–
127.5
–
127.5
–
2Gb
197.5
–
197.5
–
197.5
–
197.5
–
197.5
–
197.5
–
197.5
–
Average periodic
refresh
(commercial)
tREFI
–
7.8
–
7.8
–
7.8
–
7.8
–
7.8
–
7.8
–
7.8
s
Average periodic
refresh
(industrial)
tREFIIT
–
3.9
–
3.9
–
3.9
–
3.9
–
3.9
–
3.9
–
3.9
s
Average periodic
refresh
(automotive)
tREFIAT
–
3.9
–
3.9
–
3.9
–
3.9
–
3.9
–
3.9
–
3.9
s
CKE LOW to CK,
CK# uncertainty
tDELAY
MIN limit = tIS + tCK + tIH
MAX limit = n/a
ns
1Gb:
x4,
x8,
x16
DDR2
SDRAM
AC
Timing
Operating
Specifications
PDF:
09005aef821ae8bf
1GbDDR2.pdf
–
Rev.
S
10/09
EN
36
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Technology,
Inc.
reserves
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right
to
change
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without
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2004
Micron
Technology,
Inc.
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reserved.