K4X56163PE Datasheet, PDF (23/48 Pages) Samsung semiconductor – 16M x16 Mobile DDR SDRAM

K4X56163PE-L(F)G
Mobile-DDR SDRAM
Power down
The device enters power down mode when CKE Low,and it exits when CKE High. Once the power down mode is initiated, all of the
receiver circuits except CK and CKE are gated off to reduce power consumption. The both bank should be in idle state prior to enter-
ing the precharge power down mode and CKE should be set high at least 1 tCK+tIS prior to Row active command. During power
down mode, refresh operations cannot be performed, therefore the device cannot remain in power down mode longer than the
refresh period(tREF) of the device.
0
1
2
3
4
5
6
7
8
9
10
11
12
13
CK, CK
Command Precharge
CKE
Precharge
power
down
Entry
Precharge
power
down
Active
Exit
(NOP)
tPDEX
Active
power
down
Entry
tIS
tIS
tIS
Figure.18 Power down entry and exit timing
Active
power
down
Exit
Read
tIS
23
March 2004