
43
256Mb: x4, x8, x16 SDRAM
256MSDRAM_E.p65
–
Rev. E; Pub. 3/02
Micron Technology, Inc., reserves the right to change products or specifications without notice.
2002, Micron Technology, Inc.
256Mb: x4, x8, x16
SDRAM
AUTO REFRESH MODE
*CAS latency indicated in parentheses.
-7E
-75
SYMBOL*
t
CKH
t
CKS
t
CMH
t
CMS
t
RFC
t
RP
MIN
0.8
1.5
0.8
1.5
66
15
MAX
MIN
0.8
1.5
0.8
1.5
66
20
MAX
UNITS
ns
ns
ns
ns
ns
ns
TIMING PARAMETERS
-7E
-75
SYMBOL*
t
AH
t
AS
t
CH
t
CL
t
CK (3)
t
CK (2)
MIN
0.8
1.5
2.5
2.5
7
7.5
MAX
MIN
0.8
1.5
2.5
2.5
7.5
10
MAX
UNITS
ns
ns
ns
ns
ns
ns
tCH
tCL
tCK
CKE
CLK
DQ
tRFC
RFC
()()
(
)(
)(
)
(
)
tRP
()()
(
)(
)(
)
(
)
()()
COMMAND
tCMH
tCMS
NOP
NOP
(
)(
)(
)
(
)
BANK
ACTIVE
AUTO
REFRESH
(
)(
)(
)
(
)
NOP
NOP
PRECHARGE
Precharge all
active banks
AUTO
REFRESH
t
High-Z
BANK(S)
(
)(
)(
)
(
)
(
)(
)(
)
(
)
tAH
tAS
tCKH
tCKS
()()
NOP
(
)(
)(
)
(
)
(
)(
)(
)
(
)
DQM /
DQML, DQMU
A0-A9, A11, A12
ROW
(
)
(
)
(
)
(
)
ALL BANKS
SINGLE BANK
A10
ROW
(
)
(
)
(
)
(
)
(
)
(
)
(
)
(
)
(
)
(
)
(
)
(
)
DON
’
T CARE
T0
T1
T2
Tn + 1
To + 1