CAT5128 Datasheet, PDF (1/8 Pages) Catalyst Semiconductor – 32-Tap Digital Up/Down Control Potentiometer

32-Tap Digital Up/Down Control Potentiometer
CAT5128
FEATURES
„ 32-position linear taper potentiometer
„ Low power CMOS technology
„ Single supply operation: 2.5V – 5.5V
„ Discrete step-up/step-down digital control
„ Resistance values: 10kΩ, 50kΩ and 100kΩ
„ Available in SOT-23 8-lead Pb-free package
APPLICATIONS
„ Automated product calibration
„ Remote control adjustments
„ Offset, gain and zero control
„ Tamper-proof calibrations
„ Contrast, brightness and volume controls
„ Motor controls and feedback systems
„ Programmable analog functions
For Ordering Information details, see page 7.
DESCRIPTION
The CAT5128 is a single digitally programmable
potentiometer (DPP™) designed as an electronic
replacement for mechanical potentiometers and trim
pots. Ideal for automated adjustments on high volume
production lines, they are also well suited for
applications where equipment requiring periodic
adjustment is either difficult to access or located in a
hazardous or remote environment.
The CAT5128 contains a 32-tap series resistor array
connected between two terminals A and B. An
up/down counter and decoder that are controlled by
two input pins, determines which tap is connected to
the wiper, W. Wiper-control of the CAT5128 is
accomplished with two input control pins, U¯¯P and
¯D¯O¯W¯¯N¯. _{A high-to-low transition on the U¯¯P input}
increments the wiper position and a high-to-low
transition on the ^{¯D¯O¯W¯¯N¯} input decrements the wiper
position. The tap position is not stored in memory.
The wiper is always set to the mid point, tap 15 at
power up.
The digitally programmable potentiometer can be used
as a three-terminal resistive divider or as a two-terminal
variable resistor. DPPs bring variability and program-
mability to a wide variety of applications including
control, parameter adjustments, and signal processing.
FUNCTIONAL DIAGRAM
V_CC
UP
DOWN
UP/DOWN
Control
Power On Recall
GND
A
V_CC
W
UP
DOWN
B
GND
General
© Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
5-BIT
UP/DOWN
COUNTER
CONTROL
CIRCUITRY
31
30
29
ONE ²⁸
OF
THIRTY TWO
DECODER
2
1
0
Detailed
1
A
A
TRANSFER RESISTOR
GATES
ARRAY
W
B
W
B
Electronic Potentiometer
Implementation
Doc. No. MD-2128 Rev. A