EM68A16CBQC
EtronTech
Operation Mode
The following tables provide a quick reference of available DDR2 SDRAM commands, including CKE power-
down modes and bank-to-bank commands.
Table 4. Truth Table (Note (1), (2))
Command
BankActivate
State CKEn-1 CKEn DM BA0,1 A10 A0-9, 11-12 CS# RAS# CAS# WE#
Row address
Idle(3)
H
H
X
V
L
L
H
H
(A0 – A12)
Single Bank Precharge
All Banks Precharge
Write
Any
Any
H
H
H
H
H
H
H
H
X
X
X
X
V
X
V
V
L
H
L
X
X
L
L
L
L
L
L
H
H
L
L
L
L
L
Active(3)
Active(3)
H
H
Column
address
Write with AutoPrecharge
H
L
(A0 - A8)
Active(3)
Active(3)
H
H
H
H
X
X
V
V
L
L
L
H
H
L
L
H
H
Column
address
Read
Read and Autoprecharge
H
(A0 - A8)
(Extended) Mode Register Set
No-Operation
Idle
Any
Any
Idle
Idle
H
H
H
H
H
H
X
X
H
L
X
X
X
X
X
V
X
X
X
X
OP code
L
L
L
H
X
L
L
H
X
L
L
H
X
H
H
X
H
X
H
X
H
X
X
X
X
X
X
X
X
X
X
Device Deselect
Refresh
H
L
SelfRefresh Entry
L
L
L
H
L
X
H
X
H
X
H
X
X
X
H
X
H
X
H
X
X
SelfRefresh Exit
Idle
Idle
Any
L
H
L
H
L
X
X
X
X
X
X
X
X
X
X
X
X
H
L
Power Down Mode Entry
Power Down Mode Exit
H
L
H
Data Input Mask Disable
Data Input Mask Enable(4)
Active
Active
H
H
X
X
L
X
X
X
X
X
X
X
X
H
NOTE 1: V=Valid data, X=Don't Care, L=Low level, H=High level
NOTE 2: CKEn signal is input level when commands are provided.
CKEn-1 signal is input level one clock cycle before the commands are provided.
NOTE 3: These are states of bank designated by BA signal.
NOTE 4: LDM and UDM can be enabled respectively.
Rev. 1.1
7
Jan. /2016