X93154_08 INTERSIL [Intersil Corporation], X93154_08 Datasheet - Page 5

• Manufacturer Part Number: X93154_08
• Manufacturer: INTERSIL [Intersil Corporation]

AC Timing
Power-Up and Power-down Requirements
There are no restrictions on the power-up or power-down
conditions of V
potentiometer pins provided that V
positive than or equal to V
V
Pin Descriptions
R
The R
fixed terminals of a mechanical potentiometer. The minimum
voltage is V
R
relation to wiper movement direction selected by the U/D
input.
Up/Down (U/D)
The U/D input controls the direction of the wiper movement
and whether the counter is incremented or decremented.
Increment (INC)
The INC input is negative-edge triggered. Toggling INC will
move the wiper and either increment or decrement the
counter in the direction indicated by the logic level on the
U/D input.
Chip Select (CS)
The device is selected when the CS input is LOW. The
current counter value is stored in nonvolatile memory when
CS is returned HIGH while the INC input is also HIGH. After
the store operation is complete the X93154 will be placed in
the low power standby mode until the device is selected
once again.
CC
H
H
and R
and R
ramp rate specification is always in effect.
H
and R
L
L
references the relative position of the terminal in
SS
INC
U/D
CS
L
CC
and the maximum is V
pins of the X93154 are equivalent to the
and the voltages applied to the
t
CI
H
and V
5
L
CC
, i.e., V
t
IL
CC
is always more
t
ID
. The terminology of
t
CYC
CC
≥ V
t
IH
H,
V
L
. The
t
DI
X93154
t
IC
Principles of Operation
There are three sections of the X93154: the input control,
counter and decode section; the nonvolatile memory; and
the resistor array. The input control section operates just like
an up/down counter. The output of this counter is decoded to
turn on a single electronic switch connecting a point on the
resistor array to the wiper output. Under the proper
conditions the contents of the counter can be stored in
nonvolatile memory and retained for future use. The resistor
array is comprised of 31 individual resistors connected in
series. At either end of the array and between each resistor
is an electronic switch that transfers the connection at that
point to the wiper.
The wiper, when at either fixed terminal, acts like its
mechanical equivalent and does not move beyond the last
position. That is, the counter does not wrap around when
clocked to either extreme.
If the wiper is moved several positions, multiple taps are
connected to the wiper for t
2-terminal resistance value for the device can temporarily
change by a significant amount if the wiper is moved several
positions.
When the device is powered-down, the last wiper position
stored will be maintained in the nonvolatile memory. When
power is restored, the contents of the memory are recalled
and the wiper is set to the value last stored.
Pin Names
SYMBOL
(STORE)
V SS
V CC
U/D
INC
t
R H
CS
R L
CPH
High terminal
Low terminal
Ground
Supply voltage
Up/Down control input
Increment control input
Chip Select control input
t
F
IW
90%
(INC to V
10%
DESCRIPTION
90%
W
change). The
t
R
February 19, 2008
FN8180.3