W949D6CB Datasheet, PDF (38/60 Pages) Winbond – 512Mb Mobile LPDDR

W949D6CB / W949D2CB
512Mb Mobile LPDDR
7.6.10 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
Address
DQS
DQ
WRITE
NOP
BA,Col b
tDQSSmax
DI b
NOP
READ
BA,Col n
BA,Col n
tWTR
NOP
NOP
CL=3
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) tWTR 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.
NOP
DO n
= Don't Care
7.6.11 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.
7.6.12 Non-Interrupting Write to Precharge
CK
CK
Command
Address
DQS
DQ
WRITE
NOP
BA,Col b
t_DQSSmax
DI b
NOP
BA,Col n
NOP
NOP
t_WR
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)
PRE
BA a (or all)
= Don't Care
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Publication Release Date: Sep, 21, 2011
Revision A01-007