HY[B/E]18L256160B[C/F]X-7.5
256-Mbit Mobile-RAM
Functional Description
5) The following states must not be interrupted by any executable command; DESELECT or NOP commands must be applied
on each positive clock edge during these states.
Refreshing:
Starts with registration of an AUTO REFRESH command and ends when tRC is met. Once tRC is met, the
SDRAM is in the “all banks idle” state.
Accessing Mode
Register:
Starts with registration of a MODE REGISTER SET command and ends when tMRD has been met. Once
t
MRD is met, the SDRAM is in the “all banks idle” state.
Precharging All: Starts with registration of a PRECHARGE ALL command and ends when tRP is met. Once tRP is met, all
banks are in the idle state.
6) All states and sequences not shown are illegal or reserved.
7) Not bank-specific; requires that all banks are idle and no bursts are in progress.
8) Same as NOP command in that state.
9) 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.
10) May or may not be bank-specific; if multiple banks are to be precharged, each must be in a valid state for precharging.
11) Not bank-specific; BURST TERMINATE affects the most recent READ or WRITE burst, regardless of bank.
Table 15
Current State Bank n - Command to Bank m (different bank)
Current State
CS RAS CAS WE Command / Action
Notes
1)2)3)4)5)6)
Any
H
L
X
L
L
L
L
L
L
L
L
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 n
ACTIVE (select and activate row)
1) to 6)
1) to 6)
1) to 6)
1) to 7)
1) to 7)
1) to 6)
1) to 6)
1) to 7)
1) to 8)
1) to 6)
1) to 6)
1) to 7)
1) to 7)
1) to 6)
1) to 6)
1) to 7), 9)
1) to 9)
1) to 6)
1) to 6)
1) to 7), 9)
1) to 7), 9)
1) to 6)
Idle
RowActivating,
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 (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
Write (Auto-
Precharge
Disabled)
L
H
H
L
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
(with Auto-
Precharge)
L
H
H
L
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
Write
(with Auto-
Precharge)
L
H
H
L
H
H
L
READ (select column and start READ burst)
WRITE (select column and start 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 and after tRC 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.
Data Sheet
38
Rev. 1.11, 2007-01
07142005-CR47-RB2E
QIMONDA [ QIMONDA AG ]
