W949D6DB Datasheet, PDF (40/60 Pages) Winbond – Standard Self Refresh Mode

W949D6DB / W949D2DB
8.6.10 Interrupting Write to Read
Data for any Write burst may be truncated by a subsequent READ command as shown in the figure
below. Note that the only data-in pairs that are registered prior to the tWTR period are written to the
internal array, and any subsequent data-in must be masked with DM.
CK
CK
Command
WRITE
NOP
NOP
READ
NOP
NOP
NOP
Address
DQS
BA,Col b
t_DQSSmax
BA,Col n
t_WTR
CL=3
DQ
DI b
DO n
DM
1) Dl b = Data in to column b. DO n = Data out from column n.
2) An interrupted burst of 4 is shown, 2 data elements are written.
3 subsequent elements of Data In are applied in the programmed order following DI b.
3) t_WTR is referenced from the positive clock edge after the last Data In pair.
4) A10 is LOW with the WRITE command (Auto Precharge is disabled)
5) The READ and WRITE commands are to the same device but not necessarily to the same bank.
= Don't Care
8.6.11 Write to Precharge
Data for any WRITE burst may be followed by a subsequent PRECHARGE command to the same bank
(provided Auto Precharge was not activated). To follow a WRITE without truncating the WRITE burst,
tWR should be met as shown in the figure below.
8.6.12 Non-Interrupting Write to Precharge
CK
CK
Command
WRITE
NOP
NOP
NOP
NOP
PRE
Address
DQS
BA,Col b
t_DQSSmax
BA a (or all)
t_WR
DQ
DI b
DM
1) Dl b = Data in to column b
3 subsequent elements of Data In are applied in the programmed order following DI b.
2) A non-interrupted burst of 4 is shown.
3) t_WR is referenced from the positive clock edge after the last Data In pair.
4) A10 is LOW with the WRITE command (Auto Precharge is disabled)
= Don't Care
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Publication Release Date: Oct. 08, 2014
Revision: A01-003