256Mb: x4, x8, x16 SDRAM
Electrical Specifications – AC Operating Conditions
Electrical Specifications – AC Operating Conditions
Table 12: Electrical Characteristics and Recommended AC Operating Conditions
Notes 1–5 apply to all parameters and conditions
-6A
-7E
-75
Parameter
Symbol Min
Max
Min
–
Max
5.4
5.4
–
Min
–
Max
5.4
6
Unit Notes
Access time from CLK
(positive edge)
CL = 3
CL = 2
CL = 1
tAC(3)
tAC(2)
tAC(1)
tAH
tAS
tCH
–
–
5.4
7.56
176
–
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ms
ms
ns
ns
ns
7
7
7
–
–
–
–
–
–
Address hold time
Address setup time
CLK high-level width
CLK low-level width
Clock cycle time
0.8
1.5
2.5
2.5
6
106
206
0.8
1.5
0.8
1.5
0.8
1.5
–
0.8
1.5
2.5
2.5
7
–
0.8
1.5
2.5
2.5
7.5
10
–
–
–
–
–
–
–
–
tCL
–
–
–
CL = 3
CL = 2
CL = 1
tCK(3)
tCK(2)
tCK(1)
tCKH
tCKS
tCMH
tCMS
tDH
–
–
–
8
8
8
–
7.5
–
–
–
–
–
–
CKE hold time
CKE setup time
–
0.8
1.5
0.8
1.5
0.8
1.5
–
–
0.8
1.5
0.8
1.5
0.8
1.5
–
–
–
–
–
CS#, RAS#, CAS#, WE#, DQM hold time
CS#, RAS#, CAS#, WE#, DQM setup time
Data-in hold time
–
–
–
–
–
–
–
–
–
Data-in setup time
tDS
–
–
–
Data-out High-Z time
CL = 3
CL = 2
CL = 1
tHZ(3)
tHZ(2)
tHZ(1)
tLZ
5.4
7.56
176
–
5.4
5.4
–
5.4
6
9
9
9
–
–
–
–
–
–
–
Data-out Low-Z time
1
1
–
1
–
Data-out hold time (load)
Data-out hold time (no load)
ACTIVE-to-PRECHARGE command
tOH
3
–
3
–
3
–
tOHn
tRAS
tRC
tRCD
tREF
1.8
42
60
18
–
–
1.8
37
60
15
–
–
1.8
44
66
20
–
–
10
11
120,000
120,000
120,000
ACTIVE-to-ACTIVE command period
ACTIVE-to-READ or WRITE delay
Refresh period (8192 rows)
–
–
–
–
–
–
64
16
–
64
16
–
64
16
–
Refresh period – automotive (8192 rows) tREFAT
–
–
–
AUTO REFRESH period
tRFC
tRP
tRRD
60
18
12
66
15
14
66
20
15
PRECHARGE command period
–
–
–
ACTIVE bank a to ACTIVE bank b com-
–
–
–
mand
Transition time
tT
tWR
0.3
1.2
–
0.3
1.2
–
0.3
1.2
–
ns
ns
12
13
WRITE recovery time
1 CLK +
6ns
1 CLK +
7ns
1 CLK +
7.5ns
12
–
14
–
15
–
ns
14
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27
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