W631GG6KB-15 Datasheet, PDF (53/158 Pages) Winbond – Double Data Rate architecture: two data transfers per clock cycle

W631GG6KB
7.13.2.6 Burst Read Operation followed by a Precharge
The minimum external Read command to Precharge command spacing to the same bank is equal to AL + tRTP with tRTP being the Internal Read
Command to Precharge Command Delay. Note that the minimum ACT to PRE timing, tRAS.MIN must be satisfied as well. The minimum value for the
Internal Read Command to Precharge Command Delay is given by tRTP.MIN = max(4 × nCK, 7.5 nS). A new bank active command may be issued to the
same bank if the following two conditions are satisfied simultaneously:
1. The minimum RAS precharge time (tRP.MIN) has been satisfied from the clock at which the precharge begins.
2. The minimum RAS cycle time (tRC.MIN) from the previous bank activation has been satisfied.
Examples of Read commands followed by Precharge are show in Figure 38 and Figure 39.
T0
T1
T2
CK#
CK
Command
NOP
READ
NOP
Address
Bank a,
Col n
BL4 Operation:
DQS, DQS#
DQ
BL8 Operation:
DQS, DQS#
DQ
T3
NOP
tRTP
T4
T5
T6
NOP
PRE
Bank a,
(or all)
NOP
RL = AL + CL = 9
T7
NOP
T8
NOP
T9
T10
T11
T12
T13
T14
T15
NOP
NOP
tRP
NOP
NOP
NOP
ACT
Bank a,
Row b
NOP
Dout
n
Dout
n+1
Dout
n+2
Dout
n+3
Dout
n
Dout
n+1
Dout
n+2
Dout
n+3
Dout
n+4
Dout
n+5
Dout
n+6
Dout
n+7
NOTES: 1. RL = 9 (CL = 9, AL = 0)
2. Dout n = data-out from column n.
3. NOP commands are shown for ease of illustration; other commands may be valid at these times.
4. The example assumes tRAS.MIN is satisfied at Precharge command time (T5) and that tRC.MIN is satisfied at the next Active command time (T14).
Figure 38 – READ to PRECHARGE (RL = 9, AL = 0, CL = 9, tRTP = 4, tRP = 9)
TRANSITIONING DATA
DON'T CARE
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Publication Release Date: Feb. 27, 2013
Revision A04