X9313
The system may select the X9313, move the wiper and
deselect the device without having to store the latest wiper
position in nonvolatile memory. After the wiper movement is
performed as described above and once the new position is
reached, the system must keep INC LOW while taking CS
HIGH. The new wiper position will be maintained until
changed by the system or until a power-up/down cycle
recalled the previously stored data.
This procedure allows the system to always power-up to a
preset value stored in nonvolatile memory; then during
system operation minor adjustments could be made. The
adjustments might be based on user preference, system
parameter changes due to temperature drift, etc.
The state of U/D may be changed while CS remains LOW.
This allows the host system to enable the device and then
move the wiper up and down until the proper trim is attained.
TABLE 2. MODE SELECTION
CS
L
INC
U/D
H
L
MODE
Wiper up
L
Wiper down
H
X
L
L
L
X
Store wiper position
H
X
Standby current
X
No store, return to standby
Wiper up (not recommended)
Wiper down (not recommended)
H
L
Symbol Table
WAVEFORM
INPUTS
OUTPUTS
Must be
steady
Will be
steady
May change
from Low to
High
Will change
from Low to
High
May change
from High to
Low
Will change
from High to
Low
Don’t Care:
Changes
Allowed
Changing:
State Not
Known
N/A
Center Line
is High
Impedance
FN8177.2
5
September 9, 2005
INTERSIL [ Intersil ]
