EM639165
FUNCTION TRUTH TABLE for CKE
Current State
SELF-
REFRESH*1
CKE
n-1
H
L
L
L
L
L
L
POWER
DOWN
H
L
L
ALL BANKS
IDLE*2
H
H
H
H
H
H
H
L
ANY STATE
other than
listed above
H
H
L
L
CKE
n
X
H
H
H
H
H
L
X
H
L
H
L
L
L
L
L
L
X
H
L
H
L
/CS
X
H
L
L
L
L
X
X
X
X
X
L
H
L
L
L
L
X
X
X
X
X
/RAS /CAS
X
X
H
H
H
L
X
X
X
X
X
L
X
H
H
H
L
X
X
X
X
X
X
X
H
H
L
X
X
X
X
X
X
L
X
H
H
L
X
X
X
X
X
X
/WE
X
X
H
L
X
X
X
X
X
X
X
H
X
H
L
X
X
X
X
X
X
X
Add
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Action
INVALID
Exit Self-Refresh (Idle after tRC)
Exit Self-Refresh (Idle after tRC)
ILLEGAL
ILLEGAL
ILLEGAL
NOP (Maintain Self-Refresh)
INVALID
Exit Power Down to Idle
NOP (Maintain Power Down)
Refer to Function Truth Table
Enter Self-Refresh
Enter Power Down
Enter Power Down
ILLEGAL
ILLEGAL
ILLEGAL
Refer to Current State =Power Down
Refer to Function Truth Table
Begin CLK Susspend at Next Cycle*3
Exit CLK Susspend at Next Cycle*3
Maintain CLK Suspend
ABBREVIATIONS:
H=High Level, L=Low Level, X=Don't Care
NOTES:
1. CKE Low to High transition will re-enable CLK and other inputs asynchronously. A minimum
setup time must be satisfied before any command other than EXIT.
2. Power-Down and Self-Refresh can be entered only from the All Banks Idle State.
3. Must be legal command.
Preliminary
12
Rev 1.0
Feb. 2001
ETRON [ ETRON TECHNOLOGY, INC. ]
