HY[B/E]18L128160B[C/F]-7.5
128-Mbit Mobile-RAM
Functional DescriptionCommands
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
#,+
#+%
#3
ꢇ(IGHꢈ
2!3
#!3
7%
!ꢄꢀ!ꢅꢅ
"!ꢄꢉ"!ꢅ
ꢃ $ONgT #ARE
Figure 41 AUTO REFRESH Command
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.
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.
#,+
T20
T2#
T2#
02%
./0
!2&
./0
./0
!2&
./0
./0
!#4
#OMMAND
!DDRESS
"A !ꢉ
2OW N
2OW N
0RE !LL
!ꢅꢄ ꢇ!0ꢈ
$1
(IGHꢀ:
ꢃ $ONgT #ARE
"A !ꢉ 2OW N ꢃ BANK !ꢉ ROW N
Figure 42 Auto Refresh
Data Sheet
38
Rev. 1.71, 2007-01
05282004-NZNK-8T0D