97SD3240 Datasheet, PDF (12/39 Pages) Maxwell Technologies – 1.25Gb SDRAM 8-Meg X 40-Bit X 4-Banks

1.25Gb (8-Meg X 40-Bit X 4-Banks) SDRAM
97SD3240
Function Truth Table
The following function table shows the operations that are performed when each command is issued in each
mode of the SDRAM.
The following table assumes that CKE is High.
CURRENT STATE
Precharge
Idle
Row active
CS RAS CAS WE
H
x
x
x
L
H
H
H
L
H
L
H
L
H
L
L
L
L
H
H
L
L
H
L
L
L
L
H
L
L
L
L
H
x
x
x
L
H
H
H
L
H
L
H
L
H
L
L
L
L
H
H
L
L
H
L
L
L
L
H
L
L
L
L
H
x
x
x
L
H
H
H
L
H
L
H
L
H
L
L
L
L
H
H
L
L
H
L
L
L
L
H
L
L
L
L
ADDRESS
x
x
BA, CA, A10
BA, CA, A10
BA, RA
BA, A10
x
MODE
x
x
BA, CA, A10
BA, CA, A10
BA, RA
BA, A10
x
MODE
x
x
BA, CA, A10
BA, CA, A10
BA, RA
COMMAND
DESL
NOP
READ/READ A
WRIT/WRIT A
ACTV
PRE, PALL
REF, SELF
MRS
DESL
NOP
READ/READ A
WRIT/WRIT A
ACTV
PRE, PALL
REF, SELF
MRS
DESL
NOP
READ/READ A
WRIT/WRIT A
ACTV
BA, A10
x
MODE
PRE, PALL
REF, SELF
MRS
OPERATION
Enter IDLE after t_RP
Enter IDLE after t_RP
ILLEGAL¹
ILLEGAL¹
ILLEGAL¹
NOP²
ILLEGAL
ILLEGAL
NOP
NOP
ILLEGAL³
ILLEGAL³
Bank and row active
NOP
Refresh
Mode register set
NOP
NOP
Begin read
Begin write
Other bank active
ILLEGAL on same bank⁴
Precharge
ILLEGAL
ILLEGAL
02.04.05 Rev 3
All data sheets are subject to change without notice 12
©2005 Maxwell Technologies
All rights reserved.