W949D6DB Datasheet, PDF (10/60 Pages) Winbond – Standard Self Refresh Mode

W949D6DB / W949D2DB
6.2 Simplified State Diagram
Power
applied
Power
On
DPDSX
Precharge
All Bank
MRS
EMRS
Self
Refresh
Deep
Power
Down
REFSX REFS
DPDS
MRS
SRR
Idle
All banks
precharged
SRR ^Read
Read
REFA
Auto
Refresh
CKEL
CKEH
Active
Power
Down
ACT
CKEH
Precharge
Power
Down
CKEL
WRITE
WRITE
Row
Active
READ
WRITE
WRITEA READA
READ
Burst
Stop
BST
READ
READ
WRITEA
WRITE A
READA
PRE
PRE
PRE
READA
READ A
PRE
Precharge
PREALL
Automatic Sequence
Command Sequence
ACT=Active
EMRS=Ext. Mode Reg. Set REFSX=Exit Self Refresh
BST=Burst Terminate
MRS=Mode Register Set
READ=Read w/o Auto Precharge
CKEL=Enter Power-Down
PRE=Precharge
READA=Read with Auto Precharge
CKEH=Exit Power-Down
PREALL=Precharge All Bank WRITE=Write w/o Auto Precharge
DPDS=Enter Deep Power-Down REFA=Auto Refresh
WRITEA=Write with Auto Precharge
DPDSX=Exit Deep Power-Down REFS=Enter Self Refresh
SRR = Status Register Read
Note: Use caution with this diagram.It is indented to provide a floorplan of the possible state transitions and commands
to control them,not alldetails.In particular situations involving more than one bank are not captured in full detall.
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Publication Release Date: Oct. 08, 2014
Revision: A01-003