Datasheet

7.OPERATION
7.1. Deselect
The DESELECT function (/CS HIGH) prevents new commands from being executed by the Mobile DDR SDRAM. The Mobile
DDR SDRAM is effectively deselected. Operations already in progress are not affected.
7.2. No Operation
The NO OPERATION (NOP) command is used to instruct the selected DDR SDRAM to perform a NOP (/CS = LOW, / RAS =
/CAS = /WE = HIGH). This prevents unwanted commands from being registered during idle or wait states. Operations already in
progress are not affected.
CK
CK
CKE
CS
RAS
CAS
WE
A0-An
BA0,BA1
(High)
= Don't Care
Figure 7 — NOP Command
7.3 MODE REGISTER
The Mode Register and the Extended Mode Register are loaded via the address inputs. See Mode Register and the Extended
Mode Register descriptions for further details.
The MODE REGISTER SET command (see Figure 8) can only be issued when all banks are idle and no bursts are in progress,
and a subsequent executable command cannot be issued until tMRD (see Figure 9) is met.The values of the mode register and
extended mode register will be retained even when exiting deep power-down.
AS4C16M16MD1
256Mb MOBILE DDR SDRAM
Confidential
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Ver.1.1 Oct.2015