V58C2128(804/404/164)S
TRUTH TABLE 2 – CKE
(Notes: 1-4)
CKEn-1 CKEn
CURRENT STATE
COMMANDn
ACTIONn
Maintain Power-Down
Maintain Self Refresh
NOTES
Power-Down
Self Refresh
X
X
L
L
Power-Down
Self Refresh
DESELECT or NOP
DESELECT or NOP
Exit Power-Down
Exit Self Refresh
L
H
5
All Banks Idle
Bank(s) Active
All Banks Idle
DESELECT or NOP
DESELECT or NOP
AUTO REFRESH
See Truth Table 3
Precharge Power-Down Entry
Active Power-Down Entry
Self Refresh Entry
H
L
H
H
NOTE:
1. CKE is the logic state of CKE at clock edge n; CKE was the state of CKE at the previous clock edge.
n
n-1
2. Current state is the state of the DDR SDRAM immediately prior to clock edge n.
3. COMMANDn is the command registered at clock edge n, and ACTIONn is a result of COMMANDn.
4. All states and sequences not shown are illegal or reserved.
t
5. DESELECT or NOP commands should be issued on any clock edges occurring during the XSR period.
A minimum of 200 clock cycles is needed before applying a read command, for the DLL to lock.
V58C2128(804/404/164)S Rev. 1.6 March 2002
27
MOSEL [ MOSEL VITELIC, CORP ]
