ESMT
M52D128168A
Deep Power Down Mode Entry & Exit Cycle
Note:
DEFINITION OF DEEP POWER MODE FOR Mobile SDRAM:
Deep Power Down Mode is an operating mode to achieve maximum power reduction by cutting the power of the whole memory
of the device. Once the device enters in Deep Power Down Mode, data will not be retained. Full initialization is required when
the device exits from Deep Power Down Mode.
TO ENTER DEEP POWER DOWN MODE
1) The deep power down mode is entered by having CS and WE held low with RAS and CAS high at the rising edge of
the clock. While CKE is low.
2) Clock must be stable before exited deep power down mode.
3) Device must be in the all banks idle state prior to entering Deep Power Down mode.
TO EXIT DEEP POWER DOWN MODE
4) The deep power down mode is exited by asserting CKE high.
5) 200μs wait time is required to exit from Deep Power Down.
6) Upon exiting deep power down an all bank precharge command must be issued followed by two auto refresh commands
and a load mode register sequence.
Elite Semiconductor Memory Technology Inc.
Publication Date: Aug. 2009
Revision: 1.3 42/48
ESMT [ ELITE SEMICONDUCTOR MEMORY TECHNOLOGY INC. ]
