LG Semicon
GM72V66841CT/CLT
Function Truth Table (Continued)
Current
state
CS RAS CAS WE
Address
Command
DESL
Operation
Refresh
(auto-refresh)
H
L
L
L
L
L
L
L
L
X
H
H
H
H
L
X
H
H
L
X
H
L
X
X
X
Enter IDLE after tRC
Enter IDLE after tRC
Enter IDLE after tRC
NOP
BST
H
L
BA, CA, A10 READ/READ A ILLEGAL
BA, CA, A10 WRIT/WRIT A ILLEGAL
L
ILLEGAL
H
H
L
H
L
BA, RA
BA, A10
X
ACTV
L
PRE, PALL
REF, SELF
MRS
ILLEGAL
ILLEGAL
ILLEGAL
L
H
L
L
L
MODE
* Notes : 1. H: VIH, L: VIL, X: VIH or VIL.
The other combinations are inhibit.
2. An interval of tRWL is required between the final valid data input and the Precharge command.
3. If tRRD is not satisfied, this operation is illegal.
4. BA:Bank Address, RA:Row Address, CA:Column Address
From [ROW ACTIVE]
From [Precharge]
To [DESL], [NOP] or [BST]: These
commands result in no operation.
To [DESL], [NOP] or [BST]: When these
commands are executed, the synchronous
DRAM enters the IDLE state after tRP has
elapsed from the completion of Precharge
To [READ], [READ A]: A read operation
starts. (However, an interval of tRCD is
required.)
From [IDLE]
To [WRIT], [WRIT A]: A write operation
starts. (However, an interval of tRCD is
required.)
To [DESL], [NOP], [BST], [PRE] or
[PALL]: These commands result in no
operation.
To [ACTV]: The bank specified by the
address pins and the ROW address is
activated.
To [ACTV]: This command makes the
other bank active. (However, an interval of
t
RRD is required.) Attempting to make the
currently active bank active results in an
illegal command.
To [REF], [SELF]: The synchronous
DRAM enters refresh mode (auto-refresh or
self-refresh).
To [PRE], [PALL]: These commands set
the synchronous DRAM to Precharge
mode. (However, an interval of tRAS is
required.)
To [MRS]: The synchronous DRAM enters
the mode register set cycle.
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