W982516AH Datasheet, PDF (34/41 Pages) Winbond – 4M x 4 BANKS x 16BIT SDRAM

Operating Timing Example, continued
Autoprecharge Timing (Write Cycle)
W982516AH
(1) CAS
Latency=2
( a ) burst length = 1
Command
DQ
( b ) burst length = 2
Command
DQ
( c ) burst length = 4
Command
0
1
2
Write AP
tWR
tRP
D0
Write
D0
AP
tWR
D1
Write
DQ D0 D1 D2
( d ) burst length = 8
Command
Write
3
4
Act
Act
tRP
AP
tWR
D3
DQ
(2) CAS
Latency=3
( a ) burst length = 1
Command
DQ
( b ) burst length = 2
Command
DQ
( c ) burst length = 4
Command
DQ
( d ) burst length = 8
Command
D0 D1 D2 D3 D4
Write AP
Act
tWR
tRP
D0
Write
AP
tWR
tRP
D0 D1
Write
AP
tWR
D0 D1 D2 D3
Write
DQ D0 D1 D2 D3 D4
5
6
Act
tRP
D5 D6
Act
tRP
D5 D6
7
8
AP
tWR
D7
Act
AP
tWR
D7
9 10 11
Act
tRP
Act
tRP
Note )
Write
represents the Write with Auto precharge
command.
AP
represents the start of internal
precharging.
Act
represents the Bank Activate
command.
When the Auto precharge command is asserted, the period from Bank
Acocmtivmaatend _{to the start of internal precgarging must be at least tRAS (min).}
- 34 -