EDS2532AABH-6B Datasheet, PDF (11/48 Pages) Elpida Memory – 256M bits SDRAM (8M words x 32 bits)

EDS2532AABH-6B
Command Operation
Command Truth Table
The SDRAM recognizes the following commands specified by the /CS, /RAS, /CAS, /WE and address pins.
CKE
Function
Symbol n – 1 n
/CS
/RAS /CAS /WE BA1,BA0 A10 A0 to A11
Device deselect
DESL
H
×
H
×
×
×
×
No operation
NOP
H
×
L
H
H
H
×
Burst stop
BST
H
×
L
H
H
L
×
Read
READ
H
×
L
H
L
H
V
Read with auto precharge
READA H
×
L
H
L
H
V
Write
WRIT
H
×
L
H
L
L
V
Write with auto precharge
WRITA H
×
L
H
L
L
V
Bank activate
ACT
H
×
L
L
H
H
V
Precharge select bank
PRE
H
×
L
L
H
L
V
Precharge all banks
PALL
H
×
L
L
H
L
×
Mode register set
MRS
H
×
L
L
L
L
L
Remark: H: VIH. L: VIL. ×: VIH or VIL. V: Valid address input.
×
×
×
×
×
×
L
V
H
V
L
V
H
V
V
V
L
×
H
×
L
V
Device deselect command [DESL]
When this command is set (/CS is High), the SDRAM ignore command input at the clock. However, the internal
status is held.
No operation [NOP]
This command is not an execution command. However, the internal operations continue.
Burst stop command [BST]
This command can stop the current burst operation.
Column address strobe and read command [READ]
This command starts a read operation. In addition, the start address of burst read is determined by the column
address (see Address Pins Table in Pin Function) and the bank select address (BA0, BA1). After the read operation,
the output buffer becomes High-Z.
Read with auto-precharge [READA]
This command automatically performs a precharge operation after a burst read with a burst length of 1, 2, 4 or 8.
Column address strobe and write command [WRIT]
This command starts a write operation. When the burst write mode is selected, the column address (see Address
Pins Table in Pin Function) and the bank select address (BA0, BA1) become the burst write start address. When the
single write mode is selected, data is only written to the location specified by the column address (see Address Pins
Table in Pin Function) and the bank select address (BA0, BA1).
Write with auto-precharge [WRITA]
This command automatically performs a precharge operation after a burst write with a length of 1, 2, 4 or 8, or after a
single write operation.
Data Sheet E0494E40 (Ver. 4.0)
11