EDD51323DBH-LS
Current state
/CS
H
/RAS /CAS /WE Address
Command
DESL
Operation
NOP
Write with auto pre-
×
×
×
×
charge*1
L
L
L
L
L
L
L
H
H
H
H
L
H
H
L
H
L
×
NOP
NOP
×
BST
ILLEGAL
H
L
BA, CA, A10
BA, CA, A10
BA, RA
BA, A10
×
READ/READA
WRIT/WRIT A
ACT
ILLEGAL*14
ILLEGAL*14
ILLEGAL*11, 14
ILLEGAL*11, 14
ILLEGAL
L
H
H
L
H
L
L
PRE, PALL
L
×
Remark: H: VIH. L: VIL. ×: Don’t care.
Notes: 1. The DDR Mobile RAM is in "Precharging" state for tRP after precharge command is issued.
2. The DDR Mobile RAM reaches "IDLE" state tRP after precharge command is issued.
3. The DDR Mobile RAM is in "Refresh" state for tRFC after auto-refresh command is issued.
4. The DDR Mobile RAM is in "Activating" state for tRCD after ACT command is issued.
5. The DDR Mobile RAM is in "Active" state after "Activating" is completed.
6. The DDR Mobile RAM is in "READ" state until burst data have been output and DQ output circuits are
turned off.
7. The DDR Mobile RAM is in "READ with auto precharge" from READA command until burst data has been
output and DQ output circuits are turned off.
8. The DDR Mobile RAM is in "WRITE" state from WRIT command to the last burst data are input.
9. The DDR Mobile RAM is in "Write recovering" for tWR after the last data are input.
10. The DDR Mobile RAM is in "Write with auto precharge" until tWR after the last data has been input.
11. This command may be issued for other banks, depending on the state of the banks.
12. All banks must be in "IDLE".
13. Before executing a write command to stop the preceding burst read operation, BST command must be
issued.
14. The DDR Mobile RAM supports the concurrent auto precharge feature, a read with auto precharge or a
write with auto precharge, can be followed by any command to the other banks, as long as that command
does not interrupt the read or write data transfer, and all other related limitations apply (e.g. contention
between READ data and WRITE data must be avoided.)
The minimum delay from a read or write command with auto precharge, to a command to a different bank,
is summarized below.
To command (different bank, non-
interrupting command)
Minimum delay
From command
Read w/AP
(Concurrent AP supported)
Units
tCK
tCK
tCK
tCK
tCK
tCK
Read or Read w/AP
Write or Write w/AP
Precharge or Activate
Read or Read w/AP
Write or Write w/AP
Precharge or Activate
BL/2
CL (rounded up)+ (BL/2)
1
Write w/AP
1 + (BL/2) + tWTR
BL/2
1
Preliminary Data Sheet E1432E20 (Ver. 2.0)
19
ELPIDA [ ELPIDA MEMORY ]
