CAT5127, CAT5129
32‐tap Digital
Potentiometers (POTs)
Description
The CAT5127/CAT5129 are single digital POTs 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 CAT5127 contains a 32-tap series resistor array connected
between two terminals R
H
and R
L
. The CAT5129 contains a 32-tap
series resistor array connected between two terminals R
H
and GND.
An up/down counter and decoder that are controlled by three input
pins, determines which tap is connected to the wiper. The wiper
setting, stored in nonvolatile memory, is not lost when the device is
powered down and is automatically reinstated when power is returned.
The wiper can be adjusted to test new system values without effecting
the stored setting. Wiper-control of the CAT5127/CAT5129 is
accomplished with three input control pins, CS, U/D, and INC. The
INC input increments the wiper in the direction which is determined
by the logic state of the U/D input. The CS input is used to select the
device and also store the wiper position prior to power down.
The devices are used as two-terminal variable resistors. Digital
POTs bring variability and programmability to a wide variety of
applications including control, parameter adjustments, and signal
processing.
Features
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MSOP−8
Z SUFFIX
CASE 846AD
1
TSOT−23
TD SUFFIX
CASE 419AF
PIN CONFIGURATIONS
CAT5127
MSOP (Z)
INC
U/D
R
H
GND
1
V
CC
CS
R
L
NC
CAT5129
TSOT−23 (TD)
1
CS
GND
U/D
(Top Views)
V
CC
R
H
INC
32-position Linear Taper Potentiometer
Non-volatile EEPROM Wiper Storage
Low Standby Current
Single Supply Operation: 2.5 V – 5.5 V
Increment Up/Down Serial Interface
Resistance Values: 10 kW, 50 kW and 100 kW
CAT5127 in MSOP Packages
CAT5129 in the 6-lead TSOT23 Package
This Device is Pb-Free, Halogen Free/BFR Free and are RoHS
Compliant
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
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 8 of this data sheet.
Applications
Semiconductor Components Industries, LLC, 2013
July, 2013
−
Rev. 7
1
Publication Order Number:
CAT5127/D
CAT5127, CAT5129
CAT5127
V
CC
CAT5129
V
CC
R
P
(U/D)
(INC)
(CS)
POR
GND
Control
and
Memory
R
H
(U/D)
(INC)
(CS)
POR
Control
and
Memory
R
H
R
L
GND
Figure 1. Functional Diagrams
Table 1. PIN DESCRIPTIONS
CAT5127
Name
INC
U/D
R
H
GND
NC
R
L
CS
V
CC
Increment Control
Up/Down Control
Potentiometer High Terminal
Ground
No Connect
Potentiometer Low Terminal
Chip Select
Supply Voltage
Function
MSOP/TDFN
1
2
3
4
5
6
7
8
CAT5129
SOT23
4
3
5
2
−
−
1
6
DEVICE DESCRIPTION
INC:
Increment Control Input
The INC input moves the wiper in the up or down
direction determined by the condition of the U/D input.
U/D:
Up/Down Control Input
The U/D input controls the direction of the wiper
movement. When in a high state and CS is low, any
high-to-low transition on INC will cause the wiper to move
one increment toward the R
H
terminal. When in a low state
and CS is low, any high-to-low transition on INC will cause
the wiper to move one increment towards the R
L
terminal.
R
H
:
High End Potentiometer Terminal
R
H
is the high end terminal of the potentiometer. It is not
required that this terminal be connected to a potential greater
than the R
L
terminal. Voltage applied to the R
H
terminal
cannot exceed the supply voltage, V
CC
or go below ground,
GND.
R
L
:
Low End Potentiometer Terminal (CAT5127 only)
R
L
is the low end terminal of the potentiometer. It is not
required that this terminal be connected to a potential less
than the R
H
terminal. Voltage applied to the R
L
terminal
cannot exceed the supply voltage, V
CC
or go below ground,
GND. R
L
and R
H
are electrically interchangeable.
CS:
Chip Select
The chip select input is used to activate the control input
of the device and is active low. When in a high state, activity
on the INC and U/D inputs will not affect or change the
position of the wiper. CAT5127 has an internal pull-up
resistor on the CS input pin.
V
CC
:
Supply Input for the device.
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CAT5127, CAT5129
DEVICE OPERATION
The CAT5127 operates like a digitally controlled variable
resistor with R
H
and R
L
equivalent to the high and low
terminals. There are 32 available tap positions including the
resistor end points, R
H
and R
L
. There are 31 resistor
elements connected in series between the R
H
and R
L
terminals.
The CAT5129 operates like a digitally controlled variable
resistor with R
H
equivalent to the high terminal. There are 32
available tap positions including the resistor end points, R
H
and GND. There are 31 resistor elements connected in series
between the R
H
and GND terminals.
Operation is controlled by three inputs, INC, U/D and CS.
These inputs control a five-bit up/down counter whose
output is decoded to select the wiper position. The selected
wiper position can be stored in nonvolatile memory using
the INC and CS inputs.
Table 2. OPERATION MODES
INC
High to Low
High to Low
High
Low
X
CS
Low
Low
Low to High
Low to High
High
U/D
High
Low
X
X
X
R
H
C
H
Operation
Wiper toward H
Wiper toward L/GND
Store Wiper Position
No Store, Return to Standby
Standby
With CS set LOW, the device is selected and will respond
to the U/D and INC inputs. HIGH to LOW transitions on
INC will increment or decrement the wiper (depending on
the state of the U/D input and five-bit counter). The wiper,
when at either end terminal, acts like its mechanical
equivalent and does not move beyond the last position. The
value of the counter is stored in nonvolatile memory
whenever CS transitions HIGH while the INC input is also
HIGH. When the device is powered-down, the last stored
wiper counter position is maintained in the nonvolatile
memory. When power is restored, the contents of the memory
are recalled and the counter is set to the value stored.
With INC set low, the device may be de-selected and
powered down without storing the current wiper position in
nonvolatile memory. This allows the system to always
power up to a preset value stored in nonvolatile memory.
C
L
R
L
/GND
Figure 2. Variable Resistor Equivalent Circuit
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CAT5127, CAT5129
Table 3. ABSOLUTE MAXIMUM RATINGS
Parameters
Supply Voltage
V
CC
to GND
Inputs
CS to GND
INC to GND
U/D to GND
H to GND
L to GND
W to GND
Operating Ambient Temperature
Commercial (‘C’ or Blank suffix)
Industrial (‘I’ suffix)
Junction Temperature
Storage Temperature
Lead Soldering (10 s max)
Ratings
−0.5
to +7
−0.5
to V
CC
+0.5
−0.5
to V
CC
+0.5
−0.5
to V
CC
+0.5
−0.5
to V
CC
+0.5
−0.5
to V
CC
+0.5
−0.5
to V
CC
+0.5
0 to 70
−40
to +85
+150
−65
to 150
+300
Units
V
V
C
C
C
C
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
Table 4. RELIABILITY CHARACTERISTICS
Symbol
V
ZAP
(Note 1)
I
LTH
(Notes 1, 2)
T
DR
N
END
Parameter
ESD Susceptibility
Latch-up
Data Retention
Endurance
Test Method
MIL−STD−883, Test Method 3015
JEDEC Standard 17
MIL−STD−883, Test Method 1008
MIL−STD−883, Test Method 1003
Min
2000
100
100
1,000,000
Typ
Max
Units
V
mA
Years
Stores
1. This parameter is tested initially and after a design or process change that affects the parameter.
2. Latch-up protection is provided for stresses up to 100 mA on address and data pins from
−1
V to V
CC
+ 1 V
3. These parameters are periodically sampled and are not 100% tested.
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CAT5127, CAT5129
Table 5. DC ELECTRICAL CHARACTERISTICS
(V
CC
= +2.5 V to +5.5 V unless otherwise specified)
Symbol
POWER SUPPLY
V
CC
I
CC1
Operating Voltage Range
CAT5127
Supply Current (Increment)
CAT5129
Supply Current (Increment)
I
CC2
I
SB1
(Note 4)
Supply Current (Write)
V
CC
= 5.5 V, f = 1 MHz, I
W
= 0
V
CC
= 3.3 V, f = 1 MHz, I
W
= 0
V
CC
= 5.5 V, f = 1 MHz, I
W
= 0
V
CC
= 3.3 V, f = 1 MHz, I
W
= 0
Programming, V
CC
= 5.5 V
Programming, V
CC
= 3.3 V
Supply Current (Standby)
CS = V
CC
−
0.3 V
U/D, INC = V
CC
or GND
300
150
0.35
2.5
5.5
260
150
160
50
600
400
1
V
mA
mA
mA
mA
mA
mA
mA
Parameter
Conditions
Min
Typ
Max
Units
LOGIC INPUTS
I
IH
CAT5127 Input Leakage Current
U/D, INC = V
CC
CS = V
CC
−
0.3 V
CAT5129 Input Leakage Current
I
IL
CAT5127 Input Leakage Current
V
IN
= V
CC
U/D, INC = 0
CS = 0
CAT5129 Input Leakage Current
V
IH2
V
IL2
V
IH1
V
IL1
CMOS High Level Input Voltage
CMOS Low Level Input Voltage
CAT5129 TTL High Level Input
Voltage
CAT5129 TTL Low Level Input Voltage
3.6 V
V
CC
5.5 V
V
IN
= 0 V
2.5 V
V
CC
5.5 V
V
CC
x 0.7
−0.3
2
0
1
1
1
−1
−120
−1
V
CC
+ 0.3
V
CC
x 0.2
V
CC
0.8
mA
mA
mA
mA
mA
mA
V
V
V
V
Table 6. POTENTIOMETER CHARACTERISTICS
Symbol
R
POT
Parameter
Potentiometer Resistance
Conditions
−10
Device
−50
Device
−00
Device
R
TOL
V
RH
V
RL
RES
INL
DNL
R
Wi
TC
RPOT
(Note 6)
TC
RATIO
(Note 6)
V
N
(Note 6)
C
H
/C
L
/C
W
(Note 6)
Fc (Note 6)
4.
5.
6.
Pot Resistance Tolerance
Voltage on R
H
pin
Voltage on R
L
pin
Resolution
Integral Linearity Error
Differential Linearity Error
Wiper Resistance
V
CC
= 5 V
V
CC
= 2.5 V
TC of Pot Resistance
Ratiometric TC
Noise
Potentiometer Capacitances
Frequency Response
Passive Attenuator, 10 kW
100 kHz / 1 kHz
0
0
3.2
0.5
0.25
70
150
30
3
8/24
8/8/25
1.7
1
0.5
100
200
300
20
Min
Typ
10
50
100
20
V
CC
V
CC
%
V
V
%
LSB
LSB
W
W
ppm/C
ppm/C
nV/Hz
pF
MHz
Max
Units
kW
Latch-up protection is provided for stresses up to 100 mA on address and data pins from
−1
V to V
CC
+ 1 V
I
W
= source or sink
These parameters are periodically sampled and are not 100% tested.
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