HY[B/E]18L256160B[C/F]X-7.5
256-Mbit Mobile-RAM
Functional Description
2.4.9
AUTO REFRESH and SELF REFRESH
The Mobile-RAM requires a refresh of all rows in a rolling interval. Each refresh is generated in one of two ways:
by an explicit AUTO REFRESH command, or by an internally timed event in SELF REFRESH mode.
2.4.9.1
AUTO REFRESH
Auto Refresh is used during normal operation of the
Mobile-RAM. The command is non persistent, so it
must be issued each time a refresh is required. A
minimum row cycle time (tRC) is required between two
AUTO REFRESH commands. The same rule applies to
any access command after the auto refresh operation.
All banks must be precharged prior to the AUTO
REFRESH command.
#,+
#+%
#3
ꢌ(IGHꢍ
2!3
#!3
7%
The refresh addressing is generated by the internal
refresh controller. This makes the address bits “Don’t
Care” during an AUTO REFRESH command. The
Mobile-RAM requires AUTO REFRESH cycles at an
average periodic interval of 7.8 µs (max.). Partial array
mode has no influence on auto refresh mode.
!ꢂꢎ!ꢀꢁ
"!ꢂꢏ"!ꢀ
ꢒ $ONgT #ARE
Figure 41 AUTO REFRESH Command
#,+
T20
T2#
T2#
02%
./0
!2&
./0
./0
!2&
./0
./0
!#4
#OMMAN
"A !ꢏ
!
RESS
2OW N
2OW N
0RE !LL
!ꢀꢂ ꢌ!0ꢍ
$1
(IGHꢎ:
ꢒ $ONgT #ARE
"A !ꢏ 2OW N ꢒ BANK !ꢏ ROW N
Figure 42 Auto Refresh
Data Sheet
34
Rev. 1.11, 2007-01
07142005-CR47-RB2E
QIMONDA [ QIMONDA AG ]
