Internet Data Sheet
HY[B/E]18M256[16/32]0CF
256-Mbit DDR Mobile-RAM
TABLE 7
Current State Bank n - Command to Bank m (different bank)
Current State
CS
RAS CAS WE
Command / Action
Note
1)2)3)4)5)6)
Any
H
L
X
L
L
L
L
L
L
L
L
L
L
L
L
X
H
X
L
X
H
X
H
L
X
H
X
H
H
L
DESELECT (NOP / continue previous operation)
NO OPERATION (NOP / continue previous operation)
Any command otherwise allowed to bank m
ACTIVE (select and activate row)
1)2)3)4)5)6)
1)2)3)4)5)6)
1)2)3)4)5)6)
1)2)3)4)5)6)7)
1)2)3)4)5)6)7)
1)2)3)4)5)6)
1)2)3)4)5)6)
1)2)3)4)5)6)7)
1)2)3)4)5)6)7)8)
1)2)3)4)5)6)
1)2)3)4)5)6)
1)2)3)4)5)6)7)9)
1)2)3)4)5)6)7)
1)2)3)4)5)6)
1)2)3)4)5)6)
1)2)3)4)5)6)7)
1)2)3)4)5)6)7)8)
1)2)3)4)5)6)
1)2)3)4)5)6)
1)2)3)4)5)6)7)
1)2)3)4)5)6)7)
1)2)3)4)5)6)
Idle
Row Activating,
Active, or
Precharging
H
H
L
READ (select column and start Read burst)
WRITE (select column and start Write burst)
PRECHARGE (Deactivate row in bank or banks)
ACTIVE (select and activate row)
L
H
H
L
L
Read (Auto-
Precharge
Disabled)
L
H
H
L
H
H
L
READ (truncate Read and start new Read burst)
WRITE (truncate Read and start Write burst)
PRECHARGE (Deactivate row in bank or banks)
ACTIVE (select and activate row)
L
H
H
L
L
Write (Auto-
Precharge
Disabled)
L
H
H
L
H
H
L
READ (truncate Write and start Read burst)
WRITE (truncate Write and start new Write burst)
PRECHARGE (Deactivate row in bank or banks)
ACTIVE (select and activate row)
L
H
H
L
L
Read(with Auto- L
Precharge)
L
H
H
L
L
H
H
L
READ (truncate Read and start new Read burst)
WRITE (truncate Read and start Write burst)
PRECHARGE (deactivate row in bank or banks)
ACTIVE (select and activate row)
L
L
L
H
H
L
L
Write(with Auto-
Precharge)
L
L
L
L
L
H
H
L
H
H
L
READ (truncate Write and start Read burst)
WRITE (truncate Write and start new Write burst)
PRECHARGE (Deactivate row in bank or banks)
L
H
L
1) This table applies when CKEn-1 was HIGH and CKEn is HIGH (see Table 7) and after tXP or tXSR has been met (if the previous state was
power-down or 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 tRP has been met.Row Active: A row in the bank has been activated,
and tRCD 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 AP enabled: Starts with registration of a READ command with Auto
Precharge enabled and ends when tRP has been met. Once tRP is met, the bank is in the idle state.Write with AP enabled: Starts with
registration of a WRITE command with Auto Precharge enabled and ends when tRP has been met. Once tRP is met, the bank is in the
idle state.
4) AUTO REFRESH, SELF 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.
7) Reads or Writes listed in the Command/Action column include Reads or Writes with Auto Precharge enabled and Reads or Writes with
Auto Precharge disabled.
8) A WRITE command may be applied after the completion of the Read burst; otherwise, a BURST TERMINATE command must be used to
end the Read burst prior to issuing a WRITE command.
9) Requires appropriate DM masking.
Rev.1.44, 2007-07
13
06262007-JK8G-48BV
QIMONDA [ QIMONDA AG ]
