CAT5120, CAT5121, CAT5122
© 2008 SCILLC. All rights reserved. 1 Doc. No. MD-2121 Rev. F
Characteristics subject to change without notice
16-Tap MiniPot™ Digitally Programmable
Potentiometers with 2-Wire Interface
FEATURES
0.3µA Ultra-low standby 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: 10k, 50k and 100k
Av ailable in SC-70 and S OT-23 package s
APPLICATIONS
LCD screen adjustment
Volume control
Mechanical potentiometer replacement
Gain adjustment
Line impedance matching
For Ordering Information details, see page 10.
PIN CONFIGURATION
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: 10k, 50k and
100k. These are available in space-saving 5-pin and
6-pin SC-70 and SOT-23 packages.
FUNCTIONAL DIAGRAM
PIN DESCRIPTIONS
Name Description
VDD Power Supply
GND Ground
U/D
¯ Up/Down
¯¯¯¯¯ Control Input. With CS
¯¯ low, a
low-to-high transition increments or
decrements the wiper position.
CS
¯¯
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.
L Low Terminal of Resi stor
W Wiper Terminal of Resi stor
H High Terminal of Resi stor
16-POSITION
DECODER
UP-DOWN
COUNTER
U/D
V
DD
GND
H
L
W
CS
GND
CSU/D
H
2
CAT5122
GND
CSU/D
16 15
34
HV
DD
V
DD
V
DD
2
34
W5
CAT5120
SC-70
SOT-23
SC-70
SOT-23
SC-70
SOT-23
GND
CSU/D
16H
2L5
CAT5121
34
CAT5120, CAT5121, CAT5122
Doc. No. MD-2121 Rev. F 2 © 2008 SCILLC. All rights reserved.
Characteristics subject to change without notice
ABSOLUTE MAXIMUM RATINGS(1)
Parameters Ratings Units
VDD to GND -0.3 to +6 V
All Other Pins to GND -0.3 to (VDD + 0.3) V
Input and Output Latch-Up Immunity ±200 mA
Maximum Continuous Current into H, L and W
100k
50k
10k
±0.6
±1.3
±1.3
mA
Continuous Power Di ssipation (TA = +7 0ºC)
5-pin SC-70(2)
6-pin SC-70(2)
247
245 mW
Operating Temperature Range -40 to +85 ºC
Junction Temperature +150 ºC
Storage Temperature Range -65 to +150 ºC
Soldering Temperature (solderi ng, 10s) +300 ºC
ELECTRICAL CHARACTERISTICS
VDD = 2.7V to 5.5V, VH = VDD, VL = 0, TA = -40ºC to +85ºC. Typical values are at VDD = 2.7V, TA = 25ºC, unless
otherwise noted.
Parameter Symbol Conditions Min Typ Max Units
DC Performance
Resolution 16 Taps
End-to-End Resistance (-00) 75 100 125
End-to-End Resistance (-50) 37.5 50 62.5
End-to-End Resistance (-10) 7.5 10 12.5
k
End-to-End Resistance Tempco TCR 200 ppm/ºC
Ratiometric Resi stan ce Tempco 5 ppm/ºC
Integral Nonlinearity INL
±0.5 LSB
Differential Nonlinearity DNL
±0.5 LSB
Zero/Full-Scale Error ±0.1 ±0.5 LSB
Wiper Resistance RW 200 600
Digital Inputs
Input High Voltage VIH 0.7 x VDD V
Input Low Voltage VIL 0.3 x VDD V
Notes:
(1) Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions outside of those listed in the operational sections of this
specification is not implied. Exposure to any absolute maximum rating for extended periods may affect device performance and reliability.
(2) Derate 3.1mW/ºC above TA = +70ºC
CAT5120, CAT5121, CAT5122
© 2008 SCILLC. All rights reserved. 3 Doc. No. MD-2121 Rev. F
Characteristics subject to change without notice
ELECTRICAL CHARACTERISTICS (continued)
Parameter Symbol Conditions Min Typ Max Units
Timing Characteristics (Figures 1, 2)
U/D
¯ Mode to CS
¯¯ Setup tCU 25 ns
CS
¯¯ to U/D
¯ Step Setup tCI 50 ns
CS
¯¯ to U/D
¯ Step Hold tIC 25 ns
U/D
¯ Step Low Period tIL 25 ns
U/D
¯ Step High Period tIH 25 ns
Up/Down
¯¯¯¯¯ Toggle Rate(1) fTOGGLE 1 MHz
100k variable resistor
configuration, CL = 10pF 1
Output Settling Time (2) t
SETTLE 100k potentiometer
configuration, CL = 10pF 0.25 μs
Power Supply
Supply Voltage VDD 2.7 5.5 V
Active Supply Current (3) I
DD 25 µA
Standby Supply Current (4) I
SB V
DD = +5V 0.3 1 µA
TYPICAL OPERATING CHARACTERISTICS
TA = 25ºC, unless otherwise noted.
Notes:
(1) Up/Down Toggle Rate: SETTLE
TOGGLE t1
=f
(2) Typical settling times are dependent on end-to-end resistance.
(3) Supply current measured while changing wiper tap, fTOGGLE = 1MHz.
(4) Supply current measured while wiper position is fixed.
V
DD
= 5.5V
V
DD
= 2.7V
084 12162024
WIPER POSITION TEMPERATURE (ºC)
TEMPERATURE (ºC)
V
DD
= 2.7V
28 32
50K
V
DD
= 5.5V
CAT5120, CAT5121, CAT5122
Doc. No. MD-2121 Rev. F 4 © 2008 SCILLC. All rights reserved.
Characteristics subject to change without notice
FUNCTIONAL DESCRIPTION
The CAT5120/5121/5122 consist of a fixed resistor and
a wiper contact with 16-tap points that are digitally
controlled through a2-wire up/down serial interface.
Three end-to-e nd resistance values are av ailable: 10k,
50k and 100k.
The CAT5120 is designed to operate as a potentiometer.
In this configuration, the low terminal of the resistor array
is connected to ground (pin 2).
The CAT5122 performs as a variable resistor. In this
device, the wiper terminal and high terminal of the
resistor array is connected at pin 5. The CAT5121 is a
similar variable resistor, except the low terminal is
connected to pin 5.
Digital Interface Operation
The MiniPots have two modes of operation when the
serial interface is active: increment and decrement
mode. The se rial int erface is only active when CS
¯¯ is low.
The CS
¯¯ and U/D
¯ inputs control the position of the
wiper along the resistor array. When CS
¯¯ transitions
from high to low, the part will go into increment mode
if U/D
¯ input is high, and into decrement mode when
U/D
¯ input is low. Once the mode is set, the device will
remain in that mode until CS
¯¯ goes high again. A low-
to-high transition at the U/D
¯ pin will increment or
decrement the wiper position depending on the
current mode (Figures 1 and 2).
When the CS
¯¯ input transitions to high (serial interface
inactive), the value of the counter is stored and the
wiper position is maintained.
Note that when the wiper reaches the maximum (or
minimum) tap position, the wiper will not wrap around
to the minimum (or maximum) position.
Power-On Reset
All parts in this family feature power-on reset (POR)
circuitry that sets the wiper position to midscale at
power-up. By def ault, the ch ip is in th e increment mode.
Figure 1. Serial Interface Timing Diagram, Increment Mode
Figure 2. Serial Interface Timing Diagram, Decrement Mode
CS
U/D
W
t
CU
t
IL
t
IH
t
SETTLE
t
IC
t
CI
t
SETTLE
Note: "W " is not a digit al s ignal . It repr es ents wiper t ransitions.
CS
U/D
W
t
CU
t
IL
t
IH
t
IC
t
SETTLE
t
CI
t
SETTLE
Note: " W " is not a di gital sig nal. It r epr es e nt s wipe r tran si t i ons .
CAT5120, CAT5121, CAT5122
© 2008 SCILLC. All rights reserved. 5 Doc. No. MD-2121 Rev. F
Characteristics subject to change without notice
30V
W
L
H
+5V
V
OUT
30V
L
H
+5V
V
OU
T
V
CC
L
H
V
IN
V
OUT
V
CC
LH
W
V
IN
V
OUT
CAT5120 CAT5121
CAT5121 CAT5120
APPLICATIONS INFORMATION
The MiniPots are intended for circuits requiring
digitally controlled adjustable resistance, such as LCD
contrast control, where voltage biasing adjusts the
display contrast.
Alternative Positive LCD Bias Control
Use an op amp to provide buffering and gain on the
output of the CAT5120. Connect the mechanical
potentiometer to the positive input of a noninverting op
amp (Figure 3) to select a portion of the input signal
by digitally controlling the wiper terminal. Figure 4
shows a similar circuit for the CAT5121.
Adjustable Gain
Figure 5 shows how to use the variable resistor to
digitally adjust the gain of a noninverting op amp
configuration. Connect the CAT5121 in series with a
resistor to ground to form the adjustable gain control
of a noninverting amplifier. The Minipots have a low
5ppm/°C ratiometric tempco that allows for a very
stable adjustable gain configuration over temperature.
Figure 3. Positive LCD Bias Control
Figure 5a. Adjustable Gain Circuit Figure 5b. Adjustable Gain Circuit
Figure 4. Positive LCD Bias Control
CAT5120, CAT5121, CAT5122
Doc. No. MD-2121 Rev. F 6 © 2008 SCILLC. All rights reserved.
Characteristics subject to change without notice
PACKAGE OUTLINE DRAWINGS
SC-70 6-Lead (SD) (1)(2)
Notes:
(1) All dimensions are in millimeters. Angles in degrees.
(2) Complies with JEDEC standard MS-203.
For current Tape and Reel information, download the PDF file from:
http://www.catsemi.com/documents/tapeandreel.pdf.
θ
E1 E
D
A
L
L1 L2
ee
bA1
A2
c
TOP VIEW
SIDE VI EW END VIEW
θ1
θ1
SYMBOL MIN NOM MAX
A 0.80 1.10
A1 0.00 0.10
A2 0.80 1.00
b 0.15 0.30
c 0.10 0.18
D 1.80 2.00 2.20
E 1.80 2.10 2.40
E1 1.15 1.25 1.35
e 0.65 BSC
L 0.26 0.36 0.46
L1 0.42 REF
L2 0.15 BSC
θ
θ1 10°
CAT5120, CAT5121, CAT5122
© 2008 SCILLC. All rights reserved. 7 Doc. No. MD-2121 Rev. F
Characteristics subject to change without notice
SOT-23 6-Lead (TB) (1)(2)
Notes:
(1) All dimensions are in millimeters. Angles in degrees.
(2) Complies with JEDEC standard MO-178.
For current Tape and Reel information, download the PDF file from:
http://www.catsemi.com/documents/tapeandreel.pdf.
TOP VIEW
SIDE VIEW END VIEW
E1 E
PIN #1 IDENTIFICATION
A2
A1
e
b
D
c
Aθ
L1 L
L2
SYMBOL MIN NOM MAX
A 0.90 1.45
A1 0.00 0.15
A2 0.90 1.15 1.30
b 0.30 0.50
c 0.08 0.22
D2.90 BSC
E2.80 BSC
E1 1.60 BSC
e0.95 BSC
L 0.30 0.45 0.60
L1 0.60 REF
L2 0.25 REF
θ
θ1 10º 15º
θ2 10º 15º
θ2
θ1
CAT5120, CAT5121, CAT5122
Doc. No. MD-2121 Rev. F 8 © 2008 SCILLC. All rights reserved.
Characteristics subject to change without notice
SC-70 5-Lead (SD) (1)(2)
Notes:
(1) All dimensions are in millimeters. Angles in degrees.
(2) Complies with JEDEC standard MS-203.
For current Tape and Reel information, download the PDF file from:
http://www.catsemi.com/documents/tapeandreel.pdf.
θ
E1 E
D
A
L
L1 L2
ee
bA1
A2
c
TOP VIEW
SIDE VIEW END VIEW
θ1
θ1
SYMBOL MIN NOM MAX
A 0.80 1.10
A1 0.00 0.10
A2 0.80 1.00
b 0.15 0.30
c 0.10 0.18
D 1.80 2.00 2.20
E 1.80 2.10 2.40
E1 1.15 1.25 1.35
e 0.65 BSC
L 0.26 0.36 0.46
L1 0.42 REF
L2 0.15 BSC
θ
θ14° 10°
CAT5120, CAT5121, CAT5122
© 2008 SCILLC. All rights reserved. 9 Doc. No. MD-2121 Rev. F
Characteristics subject to change without notice
SOT-23 5-Lead (TB) (1)(2)
Notes:
(1) All dimensions are in millimeters. Angles in degrees.
(2) Complies with JEDEC standard MO-178.
For current Tape and Reel information, download the PDF file from:
http://www.catsemi.com/documents/tapeandreel.pdf.
TOP VIEW
SIDE VIEW END VIEW
E1 E
PIN #1 IDENTIFICATION
A2
A1
e
b
D
c
Aθ
L1 L
L2
θ2
θ1
SYMBOL MIN NOM MAX
A 0.90 1.45
A1 0.00 0.15
A2 0.90 1.15 1.30
b 0.30 0.50
c 0.08 0.22
D 2.90 BSC
E 2 .80 BSC
E1 1.60 BSC
e 0.95 BSC
L 0.30 0.45 0.60
L1 0.60 REF
L2 0.25 REF
θ
θ15º10º15º
θ25º10º15º
CAT5120, CAT5121, CAT5122
Doc. No. MD-2121 Rev. F 10 © 2008 SCILLC. All rights reserved.
Characteristics subject to change without notice
EXAMPLE OF ORDERING INFORMATION (1)
Notes:
(1) All packages are RoHS-compliant (Lead-free, Halogen-free).
(2) The standard finish is NiPdAu.
(3) The device used in the example above is a CAT5120SDI-10-GT3 (SC-70, Industrial Temperature, 10k, NiPdAu, Tape & Re el, 3, 000/ Reel).
(4) For additional package and temperature options, please contact your nearest ON Semiconductor Sales office.
Prefix Device # Suffix
CAT 5120 SD I -10 G T3
Optional
Company ID Temperature Range
I = Industrial (-40ºC to 85ºC)
Resistance
-10: 10k
-50: 50k
-00: 100k
Tape & Reel
T: Tape & Reel
3: 3,000/Reel
Product Number
5120
5121
5122
Package
SD: SC-70
TB: SOT-23
Lead Finish
Blank: Matte-Tin
G: NiPdAu
For Product Top Mark Codes, click here:
http://www.catsemi.com/techsupport/producttopmark.asp
CAT5120, CAT5121, CAT5122
© 2008 SCILLC. All rights reserved. 11 Doc. No. MD-2121 Rev. F
Characteristics subject to change without notice
ORDERING INFORMATION
Part Number Resistor [k] Pin Package Quantity per Reel
CAT5120SDI-10-GT3 10 SC70-6 3,000
CAT5120TBI-10-T3 10 SOT23-6 3,000
CAT5120TBI-10-GT3 10 SOT23-6 3,000
CAT5120SDI-50-GT3 50 SC70-6 3,000
CAT5120TBI-50-T3 50 SOT23-6 3,000
CAT5120TBI-50-GT3 50 SOT23-6 3,000
CAT5120SDI-00-GT3 100 SC70-6 3,000
CAT5120TBI-00-T3 100 SOT23-6 3,000
CAT5120TBI-00-GT3 100 SOT23-6 3,000
CAT5121SDI-10-GT3 10 SC70-6 3,000
CAT5121TBI-10-T3 10 SOT23-6 3,000
CAT5121TBI-10-GT3 10 SOT23-6 3,000
CAT5121SDI-50-GT3 50 SC70-6 3,000
CAT5121TBI-50-T3 50 SOT23-6 3,000
CAT5121TBI-50-GT3 50 SOT23-6 3,000
CAT5121SDI-00-GT3 100 SC70-6 3,000
CAT5121TBI-00-T3 100 SOT23-6 3,000
CAT5121TBI-00-GT3 100 SOT23-6 3,000
CAT5122SDI-10-GT3 10 SC70-5 3,000
CAT5122TBI-10-T3 10 SOT23-5 3,000
CAT5122TBI-10-GT3 10 SOT23-5 3,000
CAT5122SDI-50-GT3 50 SC70-5 3,000
CAT5122TBI-50-T3 50 SOT23-5 3,000
CAT5122TBI-50-GT3 50 SOT23-5 3,000
CAT5122SDI-00-GT3 100 SC70-5 3,000
CAT5122TBI-00-T3 100 SOT23-5 3,000
CAT5122TBI-00-GT3 100 SOT23-5 3,000
CAT5120, CAT5121, CAT5122
ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further not ice to
any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
“Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All
operating parameters, including “Typicals” must be validated for each customer application by customer's technical experts. SCILLC does not convey any license under its patent rights
nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer
purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and
distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated
with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal
Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
PUBLICATION ORDERING INFORM ATION
LITERATURE FULFILLMENT:
Literature Distribution Center for ON Semiconductor
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Phone: 303-675-2175 or 800- 344- 3 86 0 Toll F r ee USA/Ca na da
Fax: 303-675-2176 or 800-344-3867 Toll Free USA/Canada
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Order Literature: http://www.onsemi.com/orderlit
For additional information, please contact your local
Sales Representative
Doc. No. MD-2121 Rev. F 12 © 2008 SCILLC. All rights reserved.
Characteristics subject to change without notice
REVISION HISTORY
Date Rev. Description
10-Mar-05 A Initial Issue
27-Sep-06 B Update Electrical Characteristics
12-Mar-07 C
Update Ordering Information
Update Package Outlines
Add Example of Ordering Information
Add SOT-23 5 Lead package drawing
Update SOT-23 6 Lead package drawing
12-Mar-08 D
Update Package Outline Drawings
Update Ordering Information
Add MD- to document number
Add Top Mark Code link
29-May-08 E
Delete 10,000 per reel option
U
p
date Document La
y
out
21-Nov-08 F Change logo and fine print to ON Semicondu ctor
CAT5120, CAT5121, CAT5122