W632GU6NB
Publication Release Date: Aug. 20, 2018
Revision: A01
- 77 -
8.17.4 Power-Down clarifications - Case 3
If an early PD Entry is issued after a Refresh command, once PD Exit is issued, NOP or DES with
CKE High must be issued until t
RFC
(min) from the Refresh command is satisfied. This means CKE
cannot be registered low twice within a t
RFC
(min) window. A detailed example of Case 3 is shown in
Figure 71.
T0
T1
T2
Ta1
CK#
CK
REF
NOP
Tb0
NOP
NOP
NOP
t
RFC(min)
Command
NOP
Ta0
CKE
Tb1
Tc0
REF
Address
t
CPDED
Exit
Power-Down
Mode
Enter
Power-Down
Mode
t
IH
t
IS
t
IH
t
IS
t
PD
Tc1
Td0
NOP
NOP
t
XP
t
CKE
Enter
Power-Down
Mode
TIME BREAK
DON'T CARE
Figure 71
– Power-Down Entry/Exit Clarifications - Case 3