W9425G6JH_13 Datasheet, PDF (49/52 Pages) Winbond – 4 M x 4 BANKS x 16 BITS DDR SDRAM

W9425G6JH
12.23 Auto Refresh Cycle
CLK
CLK
CMD
PREA
NOP
tRP
AREF
NOP
tRFC
AREF
NOP
tRFC
CMD
Note: CKE has to be kept “High” level for Auto-Refresh cycle.
12.24 Precharged/Active Power Down Mode Entry and Exit Timing
CLK
CLK
CKE
tIH tIS tCK
CMD
Precharge/Activate
Note 1,2
Entry
CMD
NOP
tIH tIS
Exit
NOP
CMD
NOP
Note:
1. If power down occurs when all banks are idle, this mode is referred to as precharge power down.
2. If power down occurs when there is a row active in any bank, this mode is referred to as active power down.
12.25 Input Clock Frequency Change during Precharge Power Down Mode Timing
CLK
CLK
CMD
CKE
NOP NOP
Frequency Change
Occurs here
NOP
tIS
DLL
RESET
NOP
NOP
CMD
tRP
200 clocks
Minmum 2 clocks
required before
changing frequency
Stable new clock
before power down exit
- 49 -
Publication Release Date: Aug. 27, 2013
Revision A03