CAT5120_07 Datasheet, PDF (1/13 Pages) Catalyst Semiconductor – 16-Tap MiniPot TM Digitally Programmable Potentiometers with 2-Wire Interface

CAT5120, CAT5121, CAT5122
16-Tap MiniPot™ Digitally Programmable
Potentiometers with 2-Wire Interface
Features
■ 0.3µA Ultra-low supply current
■ Single-supply operation: 2.7V to 5.5V
■ Glitchless switching between resistor taps
■ Power-on reset to midscale
■ 2-Wire up/down serial interface
■ Resistance values: 10kΩ, 50kΩ and 100kΩ
■ Available in SC70 and SOT-23 packages
Applications
■ LCD screen adjustment
■ Volume control
■ Mechanical potentiometer replacement
■ Gain adjustment
■ Line impedance matching
For Ordering Information details, see page 10.
DEscription
CAT5120/5121/5122 linear-taper digitally programmable
potentiometers perform the same function as a
mechanical potentiometer or a variable resistor. These
devices consist of a fixed resistor and a wiper contact
with 16-tap points that are digitally controlled through a
2-wire up/down serial interface.
The CAT5120 is configured as a potentiometer. The
CAT5121 and CAT5122 are configured as variable
resistors. See Pin Configurations for part functionality.
Three resistance values are available: 10kΩ, 50kΩ and
100kΩ. These are available in space-saving 5-pin and
6-pin SC70 and SOT-23 packages.
Functional Diagram
H
V_DD
GND
CS
W
Pin Configuration
sC70
sOT-23
sC70
sOT-23
V_DD 
6H
V_DD 
5H
GND 2
5W
CAT5120
U/D 3
4 CS
GND 2
CAT5122
U/D 3
4 CS
sC70
sOT-23
V_DD 
6H
GND 2
5L
CAT5121
U/D 3
4 CS
U/D
L
Pin Descriptions
Name
V_DD
GND
U/D
CS
L
W
H
Description
Power Supply
Ground
Up/Down Control Input. With CS low, a low-
to-high transition increments or decrements
the wiper position.
Chip Select Input. A high-to-low CS transition
determines the mode: increment if U/D is
high, or decrement if U/D is low.
Low Terminal of Resistor
Wiper Terminal of Resistor
High Terminal of Resistor
© 2007 by Catalyst Semiconductor, Inc.

Characteristics subject to change without notice
Doc. No. 2121, Rev. C