ESMT
SIMPLIFIED TRUTH TABLE
COMMAND
Register
Refresh
Mode Register set
Auto Refresh
Entry
Self
Refresh
Exit
Bank Active & Row Addr.
Read &
Column Address
Write &
Column Address
Auto Precharge Disable
Auto Precharge Enable
Auto Precharge Disable
Auto Precharge Enable
Bank Selection
All Banks
Entry
Exit
Entry
Precharge Power Down Mode
Exit
DQM
No Operating Command
L
H
H
X
H
L
H
CKEn-1
H
H
L
H
H
CKEn
X
H
L
H
X
X
CS RAS CAS
L
L
L
H
L
L
L
L
H
X
L
H
L
L
H
X
H
L
WE
M12L128168A
Operation temperature condition -40
°
C ~85
°
C
DQM
X
X
X
X
X
X
L
H
H
X
H
H
A13
A11
A10/AP
A12
A9~A0
OP CODE
X
X
V
V
Row Address
Column
L
Address
H
(A0~A8)
Column
L
Address
H
(A0~A8)
X
L
H
X
Note
1,2
3
3
3
3
4
4,5
4
4,5
6
H
H
H
X
X
X
L
L
L
H
L
X
H
L
H
L
H
H
L
X
V
X
X
H
X
V
X
X
H
L
H
H
X
V
X
X
H
X
V
X
H
L
L
L
X
V
X
X
H
X
V
X
H
X
X
X
V
Burst Stop
Precharge
V
X
Clock Suspend or
Active Power Down
H
L
H
L
H
L
X
X
X
X
X
X
V
X
X
X
7
(V = Valid , X = Don’t Care. H = Logic High , L = Logic Low )
Note :
1.OP Code : Operating Code
A0~A11 & A13~A12 : Program keys. (@ MRS)
2.MRS can be issued only at all banks precharge state.
A new command can be issued after 2 CLK cycles of MRS.
3.Auto refresh functions are as same as CBR refresh of DRAM.
The automatical precharge without row precharge of command is meant by “Auto”.
Auto/self refresh can be issued only at all banks idle state.
4.A13~A12 : Bank select addresses.
If A13 and A12 are “Low” at read ,write , row active and precharge ,bank A is selected.
If A13 is “Low” and A12 is “High” at read ,write , row active and precharge ,bank B is selected.
If A13 is “High” and A12 is “Low” at read ,write , row active and precharge ,bank C is selected.
If A13 and A12 are “High” at read ,write , row active and precharge ,bank D is selected
If A10/AP is “High” at row precharge , A13 and A12 is ignored and all banks are selected.
5.During burst read or write with auto precharge. new read/write command can not be issued.
Another bank read/write command can be issued after the end of burst.
New row active of the associated bank can be issued at tRP after the end of burst.
6.Burst stop command is valid at every burst length.
7.DQM sampled at positive going edge of a CLK and masks the data-in at the very CLK (write DQM latency is 0), but
makes Hi-Z state the data-out of 2 CLK cycles after.(Read DQM latency is 2)
Elite Semiconductor Memory Technology Inc.
Publication Date: Oct. 2007
Revision: 1.2
7/43
ESMT [ ELITE SEMICONDUCTOR MEMORY TECHNOLOGY INC. ]
