W942508CH Datasheet, PDF (44/47 Pages) Winbond – 8M x 4 BANKS x 8 BIT DDR SDRAM

W942508CH
Timing Waveforms, continued
10.23 Auto Refresh Cycle
CLK
CLK
CMD
PREA
NOP
tRP
AREF
NOP
tRFC
AREF
NOP
tRFC
CMD
CKE has to be kept "High" level for Auto-Refresh cycle.
10.24 Active Power Down Mode Entry and Exit Timing
CLK
CLK
CKE
tIH tIS
tCK
tIH tIS
CMD
NOP
Entry
NOP
Exit
NOP
CMD
NOP
10.25 Precharged Power Down Mode Entry and Exit Timing
CLK
CLK
CKE
tIH tIS
tCK
tIH tIS
CMD
NOP
Entry
NOP
Exit
NOP
CMD
NOP
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