Data Sheet
HY[B/E]18M1G16[0/1]BF
1-Gbit DDR Mobile-RAM
FIGURE 36
Self Refresh Entry and Exit
CK
CK
tRP
> tRFC
tXSR
tRFC
CKE
Command
Address
PRE
NOP
ARF
NOP
NOP
NOP
ARF
NOP
ACT
Ba A,
Row n
Row n
A10 (AP)
DQ
Pre All
High-Z
Enter
Self Refresh
Mode
Exit from
Self Refresh
Mode
Any Command
(Auto Refresh
Recommended)
= Don't Care
TABLE 14
Timing Parameters for AUTO REFRESH and SELF REFRESH Commands
Parameter
Symbol
- 6
- 7.5
Unit Note
min. max. min. max.
1)
AUTO REFRESH to ACTIVE/AUTO REFRESH command period tRFC
72
18
120
–
–
75
22.5
120
–
–
ns
1)
PRECHARGE command period
Self refresh exit to next valid command delay
Refresh period
tRP
–
–
ns
1)
tXSR
tREF
tREFI
–
–
ns
64
7.8
64
7.8
ms
–
2)
Average periodic refresh interval (8192 rows)
–
–
µs
1) These parameters account for the number of clock cycles and depend on the operating frequency, as follows:
no. of clock cycles = specified delay / clock period; round to the next higher integer.
2) A maximum of eight AUTOREFRESH commands can be posted to the DDR Mobile-RAM device, meaning that the maximum absolute
interval between any Refresh command and the next Refresh command is 8 * tREFI.
Rev.1.0, 2007-03
44
10242006-Y557-TZXW
QIMONDA [ QIMONDA AG ]
