Datasheet
DON'T CARE
NOTE 1. BC = 4, AL = 0, CWL = 9, Preamble = 1t
CK
, t
WR
= 12
NOTE 2. Din n = data-in to column n.
NOTE 3. DES commands are shown for ease of illustration; other commands may be valid at these times.
NOTE 4. BC4 setting activated by MR0[A1:A0 = 1:0].
NOTE 5. CA Parity = Disable, CS to CA Latency = Disable, Write DBI = Disable.
NOTE 6. The write recovery time (t
WR
) is referenced from the first rising clock edge after the last write data shown at T11.
t
WR
specifies the last burst write cycle until the precharge command can be issued to the same bank.
T0 T1 T2 T3 T7 T8 T9 T10
T11
T12
TRANSITIONING DATA
Din
n
Din
n+1
Din
n+2
2 Clocks
CK#
CK
DQ
CMD
T13
DESWRITE DES DES DES DES DES DES DES DES DES
DES
BGa,Bank b
Col n
ADDR
PRE
T14 T23
DES
DES
T24 T25
Din
n+3
t
WR = 12
t
RP
DES
T26
BGa,Bankb
(or all)
BC4(Fixed) Operation:
DQS, DQS#
WL = AL + CWL = 9
Figure 143. WRITE (BC4) Fixed to PRECHARGE Operation with 1t
CK
Preamble
DON'T CARE
NOTE 1. BL = 8 / BC = 4, AL = 0, CWL = 9, Preamble = 1t
CK
, WR = 12
NOTE 2. Din n = data-in to column n.
NOTE 3. DES commands are shown for ease of illustration; other commands may be valid at these times.
NOTE 4. BC4 setting activated by MR0[A1:A0 = 0:1] and A12 =0 during WRITE command at T0.
BL8 setting activated by either MR0[A1:0 = 00] or MR0[A1:0 = 01] and A12 =1 during WRITE command at T0.
NOTE 5. CA Parity = Disable, CS to CA Latency = Disable, Write DBI = Disable.
NOTE 6. The write recovery time (WR) is referenced from the first rising clock edge after the last write data shown at T13.
WR specifies the last burst write cycle until the precharge command can be issued to the same bank.
T0 T1 T2 T3 T7 T8 T9 T10
T11
T12
TRANSITIONING DATA
Din
n
Din
n+1
Din
n+2
4 Clocks
CK#
CK
DQ
CMD
T13
DESWRITE DES DES DES DES DES DES DES DES DES
DES
BGa,Bank b
Col n
ADDR
DES
T14 T23
DES
DES
T24 T25
Din
n+3
WR = 12
t
RP
DES
T26
Din
n
Din
n+1
Din
n+2
DQ
Din
n+7
Din
n+3
Din
n+4
Din
n+5
Din
n+6
BC4(OTF) Operation:
BL8 Operation:
DQS, DQS#
DQS, DQS#
WL = AL + CWL = 9
Figure 144. WRITE (BL8/BC4) OTF with Auto PRECHARGE Operation and 1t
CK
Preamble
AS4C256M16D4
Confidential
- 122 of 201 -
Rev.1.0 Aug.2019