W9864G6DB Datasheet, PDF (39/48 Pages) Winbond – 1M x 4 BANKS x 16 BITS SDRAM

W9864G6DB
Operating Timing Example, continued
Auto Precharge Timing (Read Cycle)
0 1 2 3 4 5 6 7 8 9 10 11
(1) CAS
Latency=2
( a ) burst length = 1
Command _{Read AP}
Act
tRP
DQ
Q0
( b ) burst length = 2
Command _Read
AP
Act
tRP
DQ
Q0 Q1
( c ) burst length = 4
Command
DQ
Read
AP
Act
tRP
Q0 Q1 Q2 Q3
( d ) burst length = 8
Command
DQ
Read
AP
Act
tRP
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
(2) CAS
Latency=3
( a ) burst length = 1
Command Read AP
DQ
Act
tRP
Q0
( b ) burst length = 2
Command
DQ
Read
AP
Act
tRP
Q0 Q1
( c ) burst length = 4
Command
DQ
( d ) burst length = 8
Command
DQ
Read
Read
AP
Act
tRP
Q0 Q1 Q2 Q3
AP
Act
tRP
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
Note:
Read
represents the Read 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 Activate command to
the start of internal precgarging must be at least Rt AS (min).
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Publication Release Date: January 27, 2003
Revision A1