W942508CH Datasheet, PDF (19/47 Pages) Winbond – 8M x 4 BANKS x 8 BIT DDR SDRAM

W942508CH
8.3 Function Truth Table for CKE
CURRENT
STATE
CKE
CS
n-1 n
HX X
LH H
Self Refresh
LH L
LH L
LH L
LL X
HX X
Power Down
LH X
LL X
HH X
HL H
HL L
All Banks Idle H L L
HL L
HL L
LX X
HH X
HL H
HL L
Row Active
HL L
HL L
HL L
LX X
Any State
Other Than
HH X
Listed Above
RAS CAS WE
X
X
X
X
X
X
H
H
X
H
L
X
L
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
H
H
X
L
L
H
H
L
X
L
X
X
X
X
X
X
X
X
X
X
X
H
H
X
L
L
H
H
L
X
L
X
X
X
X
X
X
X
X
ADDRESS
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Notes:
1. Self refresh can enter only from the all banks idle state.
2. Power down can enter only from bank idle or row active state.
ACTION
INVALID
Exit Self Refresh->Idle after tXSNR
Exit Self Refresh->Idle after tXSNR
ILLEGAL
ILLEGAL
Maintain Self Refresh
INVALID
Exit Power down->Idle after tIS
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
NOTES
2
2
1
2
2
2
Remark: H = High level, L = Low level, X = High or Low level (Don’t care), V = Valid data
- 19 -
Publication Release Date: May 21, 2003
Revision A3