W948D6FBHX5E-TR Datasheet, PDF (23/60 Pages) Winbond – 256Mb Mobile LPDDR

W948D6FB / W948D2FB
256Mb Mobile LPDDR
Accessing Mode Register: Starts with registration of a MODE REGISTER SET command and ends when tMRD has been
met. Once tMRD is met, the LPDDR SDRAM will be in an „all banks idle‟ state.
Precharging All: Starts with the registration of a PRECHARGE ALL command and ends when tRP is met. Once tRP is met,
the bank will be in the idle state.
10. Not bank-specific; requires that all banks are idle and no bursts are in progress.
11. Not bank-specific. BURST TERMINATE affects the most recent READ burst, regardless of bank.
12. Requires appropriate DM masking.
13. A WRITE command may be applied after the completion of the READ burst; otherwise, a BURST TERMINATE must be
used to end the READ prior to asserting a WRITE command.
6.11.6 Truth Table - Current State BANKn, Command to BANKn
CURRENT
STATE
CS RAS CAS WE
COMMAND
HX
XX
DESELECT
Any
L
H
HH
NOP
Idle
X
X
XX
ANY
L
L
HH
ACTIVE
Row Activating, _L
H
Active, or
Precharging ^L
H
LH
LL
READ
WRITE
L
L
H L PRECHARGE
L
L
HH
ACTIVE
Read with Auto _L
H
LH
Precharge
disabled
L
H
LL
READ
WRITE
L
L
H L PRECHARGE
L
L
HH
ACTIVE
Write with Auto _L
H
Precharge
disabled
LH
LH
LL
READ
WRITE
L
L
H L PRECHARGE
L
L
HH
ACTIVE
Read with Auto ^L
H
LH
Precharge
L
H
LL
READ
WRITE
L
L
H L PRECHARGE
L
L
HH
ACTIVE
Write with Auto ^L
H
LH
Precharge
L
H
LL
READ
WRITE
L
L
H L PRECHARGE
ACTION
NOTES
NOP or Continue previous Operation
NOP or Continue previous Operation
Any command allowed to bank m
Select and activate row
Select column & start read burst
8
Select column & start write burst
8
Precharge
Select and activate row
Select column & start new read burst 8
Select column & start write burst
8,10
Precharge
Select and activate row
Select column & start read burst
8, 9
Select column & start new write burst 8
Precharge
Select and activate row
Select column & start new read burst 5, 8
Select column & start write burst
5, 8, 10
Precharge
Select and activate row
Select column & start read burst
5, 8
Select column & start new write burst 5, 8
Precharge
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Publication Release Date : Oct, 15, 2012
Revision : A01-004