EDD1204ALTA, EDD1208ALTA, EDD1216ALTA
4. Truth Table
4.1 Command Truth Table
Function
Symbol
CKE
/CS
/RAS /CAS /WE
Address
n-1
H
n
x
x
x
x
BA0 BA1
A10
x
A0-9,A11
Device deselect
No operation
DESL
NOP
H
L
L
L
x
x
H
H
L
x
H
L
x
x
x
x
H
H
H
H
x
Burst stop
BST
H
x
x
x
Read
READ
READA
WRIT
WRITA
ACT
H
H
V
L
V
Read with auto precharge
Write
H
L
H
x
L
H
L
L
V
V
Write with auto precharge
Bank active
H
V
L
H
H
x
x
L
L
L
L
H
H
H
L
Prechrage select bank
Precharge all banks
Mode register set
Extended mode register set
PRE
V
x
x
x
PALL
MRS
H
L
H
x
L
L
L
L
L
L
L
V
V
EMRS
H
L
4.2 DM Truth Table
Function
Symbol
CKE
DM
n-1
H
n
x
x
x
x
x
x
U
L
Data write enable
ENB
L
Data mask
MASK
ENBU
ENBL
H
H
Upper byte write enable
Lower byte write enable
Upper byte write inhibit
Lower byte write inhibit
H
L
x
x
L
x
H
MASKU
MASKL
H
H
x
H
H
4.3 CKE Truth Table
Current State
Function
Symbol
CKE
/CS
/RAS /CAS /WE Address
n-1
H
n
H
L
Idle
CBR (auto) refresh command
Self refresh entry
REF
SELF
SREX
L
L
L
H
x
Idle
H
Self refresh
Self refresh exit
L
H
H
L
x
H
x
x
H
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Idle
Power down entry
PWDN
PWDN
PDEX
H
H
L
L
L
H
L
H
x
H
x
Bank(s) active Power down entry
H
L
H
x
H
x
Power down
Power down exit
H
H
L
H
H
Remark H = High level, L = Low level, V = Valid, x = High or Low level (Don't care)
16
Preliminary Data Sheet E0136E30
ELPIDA [ ELPIDA MEMORY ]
