w9425g8eh Winbond Electronics Corp America, w9425g8eh Datasheet - Page 21

• Manufacturer Part Number: w9425g8eh
• Description: 8m ? 4 Banks ? 8 Bits Ddr Sdram
• Manufacturer: Winbond Electronics Corp America

8.3
Notes :
1. Self refresh can enter only from the all banks idle state.
2. Power Down occurs when all banks are idle; this mode is referred to as precharge power down.
3. Power Down occurs when there is a row active in any bank; this mode is referred to as active power down.
Remark: H = High level, L = Low level, X = High or Low level (Don’t Care), V = Valid data
Self Refresh
Power Down
All banks Idle
Row Active
Any State
Other Than
Listed Above
CURRENT
STATE
Function Truth Table for CKE
n-1
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
L
CKE
H
H
H
H
H
H
H
H
X
X
X
X
L
L
L
L
L
L
L
L
L
L
L
L
n
CS RAS CAS
X
H
X
X
X
X
X
H
X
X
H
X
X
L
L
L
L
L
L
L
L
L
L
L
H
H
H
H
H
H
X
X
X
X
X
X
X
X
X
X
X
X
X
L
L
L
L
L
H
H
H
X
X
L
X
X
X
X
X
X
X
L
L
X
X
X
X
L
L
X
X
X
WE
X
X
X
X
X
X
X
X
X
X
X
X
H
X
X
X
X
X
X
H
X
X
X
X
ADDRESS
- 21 -
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
INVALID
Exit Self Refresh -> Idle after t
Exit Self Refresh -> Idle after t
ILLEGAL
ILLEGAL
Maintain Self Refresh
INVALID
Exit Power down -> Idle after t
Maintain power down mode
Refer to Function Truth Table
Enter Power down
Enter Power down
Self Refresh
ILLEGAL
ILLEGAL
Power down
Refer to Function Truth Table
Enter Power down
Enter Power down
ILLEGAL
ILLEGAL
ILLEGAL
Power down
Refer to Function Truth Table
Publication Release Date: Jul. 04
ACTION
XSNR
XSNR
IS
Revision A01
NOTES
,
2008
2
2
1
3
3