256Mb: x4, x8, x16 SDRAM
Electrical Specifications – AC Operating Conditions
Table 12: Electrical Characteristics and Recommended AC Operating Conditions (Continued)
Notes 1–5 apply to all parameters and conditions
-6A
-7E
-75
Parameter
Symbol Min
tXSR
67
Max
Min
Max
Min
Max
Unit Notes
Exit SELF REFRESH-to-ACTIVE command
–
67
–
75
–
ns
15
Table 13: AC Functional Characteristics
Notes 2–5 apply to all parameters and conditions
Parameter
Symbol
tBDL
tCCD
tCDL
tCKED
tDAL
-6A
1
-7E
1
1
1
1
4
2
0
0
2
0
2
1
2
3
2
–
-75
Unit
Notes
16
Last data-in to burst STOP command
READ/WRITE command to READ/WRITE command
Last data-in to new READ/WRITE command
CKE to clock disable or power-down entry mode
Data-in to ACTIVE command
1
1
1
1
5
2
0
0
2
0
2
1
2
3
2
–
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
tCK
1
16
1
16
17
5
2
0
0
2
0
2
1
2
3
2
1
18, 19
19, 20
16
Data-in to PRECHARGE command
tDPL
DQM to input data delay
tDQD
tDQM
tDQZ
tDWD
tMRD
tPED
DQM to data mask during WRITEs
DQM to data High-Z during READs
WRITE command to input data delay
16
16
16
LOAD MODE REGISTER command to ACTIVE or REFRESH command
CKE to clock enable or power-down exit setup mode
Last data-in to PRECHARGE command
21
17
tRDL
19, 20
16
Data-out High-Z from PRECHARGE command
CL = 3
CL = 2
CL = 1
tROH(3)
tROH(2)
tROH(1)
16
16
1. Minimum specifications are used only to indicate the cycle time at which proper opera-
tion over the full temperature range is ensured:
0˚C ≤ TA ≤ +70˚C (commercial)
Notes:
-40˚C ≤ TA ≤ +85˚C (industrial)
-40˚C ≤ TA ≤ +105˚C (automotive)
2. An initial pause of 100μs is required after power-up, followed by two AUTO REFRESH
commands, before proper device operation is ensured. (VDD and VDDQ must be powered
up simultaneously. VSS and VSSQ must be at same potential.) The two AUTO REFRESH
command wake-ups should be repeated any time the tREF refresh requirement is excee-
ded.
3. In addition to meeting the transition rate specification, the clock and CKE must transit
between VIH and VIL (or between VIL and VIH) in a monotonic manner.
4. Outputs measured at 1.5V with equivalent load:
Q
50pF
5. AC operating and IDD test conditions have VIL = 0V and VIH = 3.0V using a measurement
reference level of 1.5V. If the input transition time is longer than 1ns, then the timing is
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256Mb_sdr.pdf - Rev. R 10/12 EN
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28
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