W942508CH Datasheet, PDF (35/47 Pages) Winbond – 8M x 4 BANKS x 8 BIT DDR SDRAM

W942508CH
Timing Waveforms, continued
10.9 Auto Precharge Timing (Read Cycle, CL = 2)
1) tRCD (READA) ≥ tRAS (min) – (BL/2) × tCK
CLK
CLK
BL=2
CMD
ACT
DQS
tRAS
tRP
READA
AP
ACT
DQ
BL=4
CMD
ACT
DQS
DQ
BL=8
CMD
ACT
DQS
DQ
READA
Q0 Q1
AP
ACT
READA
Q0 Q1 Q2 Q3
AP
ACT
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
Notes: CL2 shown; same command operation timing with CL = 2.5
In this case , the internal precharge operation begin after BL/2 cycle from READA command.
AP _{represents the start of internal precharging .}
The Read with Auto precharge command cannot be interrupted by any other command.
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Publication Release Date: May 21, 2003
Revision A3