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V55C2256164VB Rev. 1.0 April 2005
ProMOS TECHNOLOGIES
V55C2256164VB
20.2 Deep Power Down Exit
The deep power down mode is exited by asserting CKE high. After the exit, the following sequence is needed to
enter a new command:
1. Maintain NOP input conditions for a minimum of 200
µs
2. Issue precharge commands for all banks of the device
3. Issue eight or more autorefresh commands
4. Issue a mode register set command to initialize the mode register
5. Issue an extended mode register set command to initialize the extende mode register
CLK
CK E
CS
RAS
CAS
WE
tRP
All banks
200
s
Au to
Deep Power Do wn
Auto
tRC
Mode
exi t
prec harge
refresh
refresh
Register
Set
Exte nded
Mode
Regis ter
Set
New
Com mand
Acce pted
Here