W989D6DB Datasheet, PDF (19/64 Pages) Winbond – Standard Self Refresh Mode

W989D6DB / W989D2DB
8.3.2 READ with auto precharge interrupted by a READ (with or without auto precharge)
A READ to bank m will interrupt a READ on bank n following the programmed CAS latency. The precharge to
bank n begins when the READ to bank m is registered.
T0
T1
T2
T3
T4
T5
T6
T7
CLK
Command
Internal
states
Bank n
Bank m
NOP
READ-AP
Bank n
NOP
READ-AP
Bank m
NOP
NOP
Page active
READ with burst of 4
Page active
Interrupt burst, precharge
tRP-bank n
READ with burst of 4
NOP
NOP
Idle
tRP-bank m
Precharge
Address
DQ
Bank n,
Col a
Note: DQM is LOW.
Bank m,
Col d
CL=3 (bank n)
Dout
a
Dout
a+1
CL=3 (bank m)
Dout
d
Dout
d+1
Don’t Care
8.3.3 READ with auto precharge interrupted by a WRITE (with or without auto precharge)
A WRITE to bank m will interrupt a READ on bank n when registered. DQM should be used two clocks prior to the
WRITE command to prevent bus contention. The precharge to bank n begins when the WRITE to bank m is
registered.
T0
T1
T2
T3
T4
T5
T6
T7
CLK
Command
READ-AP
Bank n
NOP
NOP
Internal
states
Bank n ^Page READ with burst of 4
active
Bank m
Page active
NOP
WRITE-AP
Bank m
NOP
NOP
Interrupt burst, precharge
tRP-bank n
WRITE with burst of 4
NOP
Idle
tWR-bank m
Write-back
Address
Bank n,
Col a
Bank m,
Col d
DQM
DQ
DOUT
Din
a
d
Din
Din
d+1
d+2
CL=3 (bank n)
Note: DQM is HIGH at T2 to prevent D_OUTa + 1 from contending with D_INd at T4.
Din
d+3
Don’t Care
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Publication Release Date: Mar. 19, 2014
Revision: A01-001