K4S281632O-LC75000 Datasheet, PDF (18/18 Pages) Samsung semiconductor – 54TSOP(II) with Lead-Free & Halogen-Free (RoHS compliant)

K4S280832O
K4S281632O
datasheet
Rev. 1.0
SDRAM
18. SIMPLIFIED TRUTH TABLE
(V=Valid, X=Don′t care, H=Logic high, L=Logic low)
Command
CKEn-1 CKEn CS RAS CAS WE
Register
Mode register set
H
X
L
L
L
L
Refresh
Auto refresh
Self
refresh
Entry
Exit
H
H
L
L
L
H
L
L
H
H
H
L
H
H
X
X
X
Bank active & row addr.
H
X
L
L
H
H
Read &
Auto precharge disable
column address
Auto precharge enable
H
X
L
H
L
H
Write &
Auto precharge disable
column address
Auto precharge enable
H
X
L
H
L
L
Burst stop
H
X
L
H
H
L
Precharge
Bank selection
All banks
H
X
L
L
H
L
Clock suspend or
active power down
Entry
Exit
H
X
X
X
H
L
L
V
V
V
L
H
X
X
X
X
Precharge power down mode
Entry
Exit
H
X
X
X
H
L
L
H
H
H
H
X
X
X
L
H
L
V
V
V
DQM
H
X
No operation command
H
X
X
X
H
X
L
H
H
H
NOTE :
1. OP Code : Operand code
A0 ~ A11 & BA0 ~ BA1 : 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 command is meant by "Auto".
Auto/self refresh can be issued only at all banks precharge state.
4. BA0 ~ BA1 : Bank select addresses.
If both BA0 and BA1 are "Low" at read, write, row active and precharge, bank A is selected.
If BA0 is "High" and BA1 is "Low" at read, write, row active and precharge, bank B is selected.
If BA0 is "Low" and BA1 is "High" at read, write, row active and precharge, bank C is selected.
If both BA0 and BA1 are "High" at read, write, row active and precharge, bank D is selected.
If A10/AP is "High" at row precharge, BA0 and BA1 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)
DQM
X
X
X
X
X
X
X
X
BA0,1
V
V
V
V
X
A10/AP
A0 ~ A9,
A11,
OP code
X
X
Row address
L
Column
H
address
L
Column
H
address
X
L
X
H
NOTE
1,2
3
3
3
3
4
4,5
4
4,5
6
X
X
X
X
X
X
V
X
7
X
X
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