VIS
2.Truth Table
2.1 Command Truth Table
FUNCTION
Device deselect
No operation
Mode register set
Bank activate
Read
Read with auto precharge
Write
Write with auto precharge
Precharge select bank
Precharge all banks
Burst stop
CBR (Auto) refresh
Self refresh
Symbol
DESL
NOP
MRS
ACT
READ
READA
WRIT
WRITA
PRE
PALL
BST
REF
SELF
CKE
n-1
n
H
H
H
H
H
H
H
H
H
H
H
H
H
X
X
X
X
X
X
X
X
X
X
X
H
L
Preliminary
VG3664321(4)1(2)BT
CMOS Synchronous Dynamic RAM
CS
H
L
L
L
L
L
L
L
L
L
L
L
L
RAS
X
H
L
L
H
H
H
H
L
L
H
L
L
CAS
X
H
L
H
L
L
L
L
H
H
H
L
L
WE
X
H
L
H
H
H
L
L
L
L
L
H
H
BA
(1)
X
X
L
V
V
V
V
V
V
X
X
X
X
A10
X
X
L
V
L
H
L
H
L
H
X
X
X
A9 - A0
X
X
V
V
V
V
V
V
X
X
X
X
X
Notes : (1) Bank address. lt would be different from organizations.
2.2 DQM Truth Table
FUNCTION
Data write/output enable
Data mask/output disable
DQ24 ~ DQ31 write enable/output enable
DQ16 ~ DQ23 write enable/output enable
DQ8 ~ DQ7 write enable/output enable
DQ0 ~ DQ7 write enable/output enable
DQ24 ~ DQ31 write enable/output enable
DQ16 ~ DQ23 write enable/output enable
DQ8 ~ DQ15 write enable/output enable
DQ0 ~ DQ7 write enable/output enable
Symbol
ENB
MASK
ENB3
ENB2
ENB1
ENB0
MASK3
MASK2
MASK1
MASK0
CKE
n-1
n-1
H
X
H
X
H
X
H
X
H
X
H
X
H
X
H
X
H
X
H
X
DQM
3
2
L
H
L
X
X
X
H
X
X
X
X
L
X
X
X
H
X
X
X
X
L
X
X
X
H
X
X
X
L
X
X
X
H
1
0
2.3 CKE Truth Table
Current State
Activating
Any
Clock suspend
Idle
Idle
Self refresh
Idle
Power down
Function
Clock suspend mode entry
Clock suspend
Clock suspend mode exit
CBR refresh command
Self refresh entry
Self refresh exit
Power down entry
Power down exit
Symbol
CKE
n-1
H
L
L
H
H
L
L
H
L
n
L
L
H
H
L
H
H
L
H
CS
X
X
X
L
L
L
H
X
X
RAS
X
X
X
L
L
H
X
X
X
CAS
X
X
X
L
L
H
X
X
X
Add
WE ress
X
X
X
X
X
X
H
X
H
X
H
X
X
X
X
X
X
X
REF
SELF
H : High level, L : Low level
X : High or Low level (Don’t care), V : Valid Data input
Document : 1G5-0099
Rev.1
Page 10
VML [ VANGUARD INTERNATIONAL SEMICONDUCTOR ]
