HYB25D512800BT Datasheet, PDF (58/90 Pages) Infineon Technologies AG – 512Mbit Double Data Rate SDRAM

HYB25D512[40/16/80]0B[E/F/C/T]
512Mbit Double Data Rate SDRAM
Functional Description
Table 12 Truth Table 4: Current State Bank n - Command to Bank m (different bank)
Current State CS
Any
H
L
Idle
X
Row Activating, L
Active, or Pre _L
charging
L
L
Read (Auto
L
Precharge
L
Disabled)
L
Write (Auto
L
Precharge
L
Disabled)
L
L
Read (With Auto L
Precharge)
L
L
L
Write (With Auto L
Precharge)
L
L
L
RAS CAS WE
XXX
HHH
XXX
L HH
HL H
HL L
L HL
L HH
HL H
Command
Deselect
No Operation
Any Command
Otherwise Allowed
to Bank m
Active
Read
Write
Precharge
Active
Read
L H L Precharge
L H H Active
H L H Read
H L L Write
L H L Precharge
L H H Active
H L H Read
H L L Write
L H L Precharge
L H H Active
H L H Read
H L L Write
L H L Precharge
Action
Notes
NOP. Continue previous operation. ^1)2)3)4)5)6)
NOP. Continue previous operation. ^{1) to 6)}
–
1) to 6)
Select and activate row
1) to 6)
Select column and start Read burst ^{1) to 7)}
Select column and start Write burst ^{1) to 7)}
–
1) to 6)
Select and activate row
1) to 6)
Select column and start new Read ^{1) to 7)}
burst
–
1) to 6)
Select and activate row
1) to 6)
Select column and start Read burst ^{1) to 8)}
Select column and start new Write ^{1) to 7)}
burst
–
1) to 6)
Select and activate row
1) to 6)
Select column and start new Read ^{1) to 7), 9)}
burst
Select column and start Write burst ^{1) to 7), 9), 10)}
–
1) to 6)
Select and activate row
1) to 6)
Select column and start Read burst ^{1) to 7), 9)}
Select column and start new Write ^{1) to 7), 9)}
burst
–
1) to 6)
1) This table applies when CKE n-1 was HIGH and CKE n is HIGH (see Table 10: Clock Enable (CKE) and after t_XSNR/t_XSRD
has been met (if the previous state was self refresh).
2) This table describes alternate bank operation, except where noted, i.e., the current state is for bank n and the commands
shown are those allowed to be issued to bank m (assuming that bank m is in such a state that the given command is
allowable). Exceptions are covered in the notes below.
3) Current state definitions:
Idle: The bank has been precharged, and t_RP has been met.
Row Active: A row in the bank has been activated, and t_RCD has been met. No data bursts/accesses and no register
accesses are in progress.
Read: A Read burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated.
Write: A Write burst has been initiated, with Auto Precharge disabled, and has not yet terminated or been terminated.
Read with Auto Precharge Enabled: See ¹⁰⁾.
Write with Auto Precharge Enabled: See ¹⁰⁾.
4) AUTO REFRESH and Mode Register Set commands may only be issued when all banks are idle.
5) A BURST TERMINATE command cannot be issued to another bank; it applies to the bank represented by the current state
only.
6) All states and sequences not shown are illegal or reserved.
Data Sheet
58
Rev. 1.2, 2004-06