EDE1104ACSE, EDE1108ACSE, EDE1116ACSE
Burst Write with Auto-Precharge [WRITA]
If A10 is high when a write command is issued, the Write with auto-precharge function is engaged. The DDR2
SDRAM automatically begins precharge operation after the completion of the burst writes plus write recovery time
(tWR). The bank undergoing auto-precharge from the completion of the write burst may be reactivated if the
following two conditions are satisfied.
(1) The data-in to bank activate delay time (tWR + tRP) has been satisfied.
(2) The /RAS cycle time (tRC) from the previous bank activation has been satisfied.
T0
T1
T2
T3
T4
T5
T6
T7
Tm
/CK
CK
A10 = 1
Posted
WRIT
NOP
Command
ACT
DQS, /DQS
≥tWR
≥ tRP
WL = RL –1 = 2
in0
in1
in2
in3
DQ
tRC (min.)
Auto precharge begins
Completion of the burst write
Burst Write with Auto-Precharge (tRC Limit) (WL = 2, tWR =2)
T0
T3
T4
T5
T6
T7
T8
T9
T10
T11
/CK
CK
A10 = 1
Posted
WRIT
NOP
Command
NOP
ACT
DQS, /DQS
tRP (min.)
tWR (min.)
WL = RL –1 = 4
in0
in1
in2
in3
DQ
≥ tRC
Auto precharge begins
Completion of the burst write
Burst Write with Auto-Precharge (tWR + tRP) (WL = 4, tWR =2, tRP=3)
Data Sheet E0975E50 (Ver.5.0)
68