HYB25D256[400/800/160]B[T/C](L)
256-Mbit Double Data Rate SDRAM
Functional Description
3.6
Simplified State Diagram
Power
Applied
Power
On
Self
Refresh
Precharge
PREALL
REFS
REFSX
MRS
EMRS
Auto
Refresh
MRS
REFA
Idle
CKEL
CKEH
Active
Power
Down
ACT
Precharge
Power
Down
CKEH
CKEL
Write
Burst Stop
Row
Active
Read
Write A
Read A
Write
Read
Read
Read A
Write A
Read
A
PRE
Write
A
Read
A
PRE
PRE
Precharge
PREALL
PRE
Automatic Sequence
Command Sequence
PREALL = Precharge All Banks
MRS = Mode Register Set
EMRS = Extended Mode Register Set
REFS = Enter Self Refresh
REFSX = Exit Self Refresh
REFA = Auto Refresh
CKEL = Enter Power Down
CKEH = Exit Power Down
ACT = Active
Write A = Write with Autoprecharge
Read A = Read with Autoprecharge
PRE = Precharge
Figure 32 Simplified State Diagram
Data Sheet
53
Rev. 1.21, 2004-07
02102004-TSR1-4ZWW