W9864G6IH_10 Datasheet, PDF (17/44 Pages) Winbond – 1M × 4BANKS × 16BITS SDRAM

W9864G6IH
8. These parameters account for the number of clock cycles and depend on the operating frequency
of the clock, as follows the number of clock cycles = specified value of timing/ clock period (count
fractions as whole number)
(1)tCH is the pulse width of CLK measured from the positive edge to the negative edge referenced to VIH (min.).
tCL is the pulse width of CLK measured from the negative edge to the positive edge referenced to VIL (max.).
(2)A.C Latency Characteristics
CKE to clock disable (CKE Latency)
DQM to output to HI-Z (Read DQM Latency)
DQM to output to HI-Z (Write DQM Latency)
Write command to input data (Write Data Latency)
CS to Command input ( CS Latency)
Precharge to DQ Hi-Z Lead time
Precharge to Last Valid data out
Bust Stop Command to DQ Hi-Z Lead time
Bust Stop Command to Last Valid Data out
Read with Auto-precharge Command to Active/Ref Command
Write with Auto-precharge Command to Active/Ref Command
CL = 2
CL = 3
CL = 2
CL = 3
CL = 2
CL = 3
CL = 2
CL = 3
CL = 2
CL = 3
CL = 2
CL = 3
1
2
0
0
0
2
3
1
2
2
3
1
2
BL + t_RP
BL + t_RP
(BL+1) + t_RP
(BL+1) + t_RP
tCK
tCK + nS
9. Assumed input rise and fall time (tT ) = 1nS.
If tr & tf is longer than 1nS, transient time compensation should be considered,
i.e., [(tr + tf)/2-1]nS should be added to the parameter
( The tT maximum can’t be more than 10nS for low frequency application. )
10. If clock rising time (tT) is longer than 1nS, (tT/2-0.5)nS should be added to the parameter.
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Publication Release Date: Mar. 22, 2010
Revision A11