General Description
The MAX5471/MAX5472/MAX5474/MAX5475 linear-
taper digital potentiometers function as mechanical
potentiometers, but replace the mechanics with a sim-
ple 3-wire up/down digital interface. These digital
potentiometers feature nonvolatile memory (EEPROM)
to return the wiper to its previously stored position upon
power-up.
The MAX5471/MAX5472 are 2-terminal, variable resistors
in 6-pin SOT23 packages. The MAX5474/MAX5475 are
3-terminal potentiometers in 8-pin SOT23 packages.
The MAX5471/MAX5474 have an end-to-end resistance
of 50kΩ, and the MAX5472/MAX5475 have an end-
to-end resistance of 100kΩ. All of these devices have
32 wiper positions, a low ratiometric temperature coeffi-
cient (5ppm/°C), and all operate from a single +2.7V to
+5.25V supply. Each device is guaranteed over the
extended -40°C to +85°C temperature range.
Applications
Mechanical Potentiometer Replacement
Liquid-Crystal-Display (LCD) Screen Adjustment
Audio Volume Control
Programmable Filters
Features
Wiper Position Stored in Nonvolatile Memory and
Recalled Upon Power-Up
Tiny SOT23 Package
35ppm/°C End-to-End Resistance Temperature
Coefficient
5ppm/°C Ratiometric Temperature Coefficient
32 Tap Positions
Voltage-Divider or Variable-Resistor
Potentiometer Configuration
50kΩand 100kΩEnd-to-End Resistance Values
1µA (max) Static Supply Current
2.7V to 5.25V Single-Supply Operation
200,000 Wiper Store Cycles
50-Year Wiper Data Retention
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
________________________________________________________________ Maxim Integrated Products 1
Ordering Information
19-3067; Rev 1; 2/06
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
EVALUATION KIT
AVAILABLE
PART TEMP
RANGE PIN-PACKAGE PKG
CODE
M A X5 4 7 1 E Z T- T- 40° C to + 85° C 6 Thin SOT23-6 Z6-1
M A X5 4 7 2 E Z T- T- 40° C to + 85° C 6 Thin SOT23-6 Z6-1
M A X5 4 7 4 E KA- T- 40° C to + 85° C 8 SOT23-8 K8S-3
M A X5 4 7 5 E KA- T- 40° C to + 85° C 8 SOT23-8 K8S-3
TOP VIEW
L
GND H
INC
W
1
GND
SOT23-6
SOT23-8
2
3
6
5
4
CS
U/D
U/D
MAX5471
MAX5472
1
VDD
VDD
H2
3
8
7
6
CS
MAX5474
MAX5475
45
INC
Pin Configurations
PART END-TO-END
RESISTANCE (kΩ)TOP MARK
MAX5471EZT 50 ABQN
MAX5472EZT 100 ABQM
MAX5474EKA 50 AEIZ
MAX5475EKA 100 AEIY
Selector Guide
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VDD = +2.7V to +5.25V, VH= VDD, VL= GND, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5.0V, TA
= +25°C, unless otherwise noted.) (Note 1)
Stresses beyond 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 beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
VDD to GND...........................................................-0.3V to +6.0V
All Other
Pins to GND .........-0.3V to the lower of (VDD + 0.3V) or +6.0V
Maximum Continuous Current into H, L, and W
MAX5471/MAX5474 .....................................................±1.3mA
MAX5472/MAX5475 .....................................................±0.6mA
Continuous Power Dissipation (TA= +70°C)
6-Pin SOT23 (derate 9.1mW/°C above +70°C)............727mW
8-Pin SOT23 (derate 8.9mW/°C above +70°C)............714mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-60°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
DC PERFORMANCE
Resolution N 32 Tap
MAX5471/MAX5474 37.5 50 62.5
End-to-End Resistance MAX5472/MAX5475 75 100 125 kΩ
End-to-End Resistance
Temperature Coefficient TCR35 ppm/°C
Ratiometric Resistance
Temperature Coefficient 5 ppm/°C
Variable-resistor mode (Note 2) ±0.5 ±1.0
Integral Nonlinearity INL Voltage-divider mode (MAX5474/MAX5475)
(Note 3) ±0.1 ±0.5 LSB
Variable-resistor mode (Note 2) ±0.5 ±1.0
Differential Nonlinearity DNL Voltage-divider mode (MAX5474/MAX5475)
(Note 3) ±0.1 ±0.5 LSB
Full-Scale Error MAX5474/MAX5475 -0.5 LSB
Zero-Scale Error MAX5474/MAX5475 +0.5 LSB
Wiper Resistance RWMAX5474/MAX5475 (Note 4) 600 1200 Ω
DIGITAL INPUTS (CS, U/D, INC) (Note 5)
VDD < 3.6V 0.7 x VDD
Input High Voltage VIH VDD 3.6V 2.4 V
VDD < 3.6V 0.3 x VDD
Input Low Voltage VIL VDD 3.6V 0.8 V
Input Current IIN ±0.1 ±1 µA
DYNAMIC CHARACTERISTICS
MAX5471/MAX5474 400
Wiper -3dB Bandwidth (Note 6) MAX5472/MAX5475 200 kHz
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
_______________________________________________________________________________________ 3
Note 1: All devices are production tested at TA= +25°C and are guaranteed by design and characterization for -40°C < TA< +85°C.
Note 2: The DNL and INL are measured with the potentiometer configured as a variable resistor. For the 3-terminal potentiometers
(MAX5474/MAX5475), H is unconnected and L = GND. At VDD = 5.25V, W is driven with a source current of 80µA for the
50kΩconfiguration, and 40µA for the 100kΩconfiguration. At VDD = 2.7V, the wiper terminal is driven with a source current
of 40µA for the 50kΩconfiguration, and 20µA for the 100kΩconfiguration.
Note 3: The DNL and INL are measured with the potentiometer configured as a voltage-divider with H = VDD and L = GND
(MAX5474/MAX5475 only). The wiper terminal is unloaded.
Note 4: The wiper resistance is the worst value measured by injecting the currents given in Note 2 into W with L = GND.
RW= (VW- VH) / IW.
Note 5: The device draws higher supply current when digital inputs are driven with voltages between 0.3V x VDD and 0.7 x VDD.
Drive the digital inputs as close as possible to VDD or GND. (See the Typical Operating Characteristics for the Supply
Current vs. Digital Input Voltage graph.)
Note 6: Wiper at midscale with a 10pF load.
Note 7: Digital timing is guaranteed by design and characterization, and is not production tested.
Note 8: Wiper settling time is the worst-case 0% to 50% rise time measured between consecutive wiper positions. H = VDD, L =
GND, and the wiper terminal is unloaded and measured with a 10pF oscilloscope probe (see the Typical Operating
Characteristics for the Tap-to-Tap Switching Transient).
Note 9: Digital inputs CS, U/D, and INC are connected to GND or VDD. See the Typical Operating Characteristics for the Static
Supply Current vs. Temperature graph.
ELECTRICAL CHARACTERISTICS (continued)
(VDD = +2.7V to +5.25V, VH= VDD, VL= GND, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VDD = +5.0V, TA
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
TIMING CHARACTERISTICS (Figure 1, Note 7)
CS to INC Setup tCI 50 ns
INC High to U/D Change tID 0ns
U/D to INC Setup tDI 100 ns
INC Low Period tIL 50 ns
INC High Period tIH 50 ns
INC Cycle Time tCYC 100 ns
INC Inactive to CS Inactive tIC 100 ns
INC Active to CS Inactive tIK 100 ns
CS Deselect Time (Store) tCPH 100 ns
Wiper Settling Time tIW (Note 8) 1 µs
Power-Up to Wiper Stable tPU s
Wiper Store Cycle tWSC 12 ms
NONVOLATILE MEMORY RELIABILITY
Data Retention TA = +85°C 50 Year
TA = +25°C 200,000
Endurance TA = +85°C 50,000 Store
POWER SUPPLY
Supply Voltage VDD 2.70 5.25 V
Supply Current IDD Write to memory 400 µA
Static Supply Current ISD TA = +25°C (Note 9) 0.35 1 µA
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
4 _______________________________________________________________________________________
Typical Operating Characteristics
(VDD = 5.0V, TA= +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX5471 toc01
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (μA)
5.14.74.33.93.53.1
0.1
0.2
0.3
0.4
0.5
0
2.7 5.5
DIGITAL INPUTS = GND OR VDD
STATIC SUPPLY CURRENT
vs. TEMPERATURE
MAX5471 toc02
TEMPERATURE (°C)
SUPPLY CURRENT (μA)
603510-15
0.1
0.2
0.3
0.4
0.5
0
-40 85
DIGITAL INPUTS = GND OR VDD
VDD = 5.0V
VDD = 3.0V
SUPPLY CURRENT
vs. DIGITAL INPUT VOLTAGE
MAX5471 toc03
DIGITAL INPUT VOLTAGE (V)
SUPPLY CURRENT (μA)
4321
1
10
100
1000
10,000
0.1
05
VDD = 5.0V
VDD = 3.0V
WIPER RESISTANCE
vs. TAP POSITION (MAX5474)
MAX5471 toc04
TAP POSITION
WIPER RESISTANCE (Ω)
252051015
250
300
350
400
450
500
550
600
200
030
VDD = 3.0V
VDD = 5.0V
WIPER RESISTANCE
vs. TAP POSITION (MAX5475)
MAX5471 toc05
TAP POSITION
WIPER RESISTANCE (Ω)
252051015
250
300
350
400
450
500
550
600
200
030
VDD = 3.0V
VDD = 5.0V
END-TO-END RESISTANCE % CHANGE
vs. TEMPERATURE
MAX5471 toc06
TEMPERATURE (°C)
END-TO-END RESISTANCE % CHANGE
6035-15 10
-0.15
-0.10
-0.05
0
0.05
0.10
0.15
0.20
-0.20
-40 85
100kΩ100kΩ
50kΩ
50kΩ
W-TO-L RESISTANCE
vs. TAP POSITION
MAX5471 toc07
TAP POSITION
W-TO-L RESISTANCE (kΩ)
252015105
20
40
60
80
100
0
030
MAX5475
MAX5474
H-TO-GND RESISTANCE
vs. TAP POSITION
MAX5471 toc08
TAP POSITION
H-TO-GND RESISTANCE (kΩ)
252015105
20
40
60
80
100
0
030
MAX5472
MAX5471
TAP-TO-TAP SWITCHING TRANSIENT
MAX5471 toc09
400ns/div
INC
5V/div
W
100mV/div
CL = 10pF
VH = VDD
TAP 16 TO TAP 15
MAX5474
MAX5475
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
_______________________________________________________________________________________ 5
WIPER TRANSIENT AT POWER-ON
(MAX5475)
MAX5471 toc11
1.0μs/div
VDD
5V/div
W
1V/div
CL = 10pF
TAP 16
VH = VDD
WIPER RESPONSE vs. FREQUENCY
MAX5471toc12
FREQUENCY (kHz)
WIPER RESPONSE (dB)
10010
-15
-12
-9
-6
-3
0
-18
1 1000
TAP = 16
CL = 10pF
MAX5474
MAX5475
RESISTANCE DNL vs. TAP POSITION
(MAX5471)
MAX5471 toc13
TAP POSITION
RESISTANCE DNL
252015105
-0.2
-0.1
0
0.1
0.2
0.3
-0.3
030
VARIABLE-RESISTOR MODE
RESISTANCE INL vs. TAP POSITION
(MAX5471)
MAX5471 toc14
TAP POSITION
RESISTANCE INL
252015105
0
0.1
0.2
0.3
0.4
0.5
-0.1
030
VARIABLE-RESISTOR MODE
RESISTANCE DNL vs. TAP POSITION
(MAX5472)
MAX5471 toc15
TAP POSITION
RESISTANCE DNL
252015105
-0.2
-0.1
0
0.1
0.2
0.3
-0.3
030
VARIABLE-RESISTOR MODE
RESISTANCE INL vs. TAP POSITION
(MAX5472)
MAX5471 toc16
TAP POSITION
RESISTANCE INL
252015105
0
0.1
0.2
0.3
0.4
0.5
-0.1
030
VARIABLE-RESISTOR MODE
RESISTANCE DNL vs. TAP POSITION
(MAX5474)
MAX5471 toc17
TAP POSITION
RESISTANCE DNL
252015105
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
0.04
-0.04
030
VOLTAGE-DIVIDER MODE
RESISTANCE INL vs. TAP POSITION
(MAX5474)
MAX5471 toc18
TAP POSITION
RESISTANCE INL
252015105
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
0.04
-0.04
030
VOLTAGE-DIVIDER MODE
Typical Operating Characteristics (continued)
(VDD = 5.0V, TA= +25°C, unless otherwise noted.)
WIPER TRANSIENT AT POWER-ON
(MAX5474)
MAX5471 toc10
1.0μs/div
VDD
5V/div
W
1V/div
CL = 10pF
TAP 16
VH = VDD
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
6 _______________________________________________________________________________________
Pin Description
RESISTANCE DNL vs. TAP POSITION
(MAX5475)
MAX5471 toc19
TAP POSITION
RESISTANCE DNL
252015105
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
0.04
-0.04
030
VOLTAGE-DIVIDER MODE
RESISTANCE INL vs. TAP POSITION
(MAX5475)
MAX5471 toc20
TAP POSITION
RESISTANCE INL
252015105
-0.03
-0.02
-0.01
0
0.01
0.02
0.03
0.04
-0.04
030
VOLTAGE-DIVIDER MODE
Typical Operating Characteristics (continued)
(VDD = 5.0V, TA= +25°C, unless otherwise noted.)
PIN
MAX5471/
MAX5472
MAX5474/
MAX5475
NAME FUNCTION
11CS Chip-Select Input. Drive low to change wiper position (W) through INC and U/D. A low-to-
high transition with INC high stores the wiper position in nonvolatile memory.
2 3 GND Ground
34U/DUp/Down Control Input. With U/D low, a high-to-low INC transition decrements the wiper
position. With U/D high, a high-to-low INC transition increments the wiper position.
45INC Wiper Increment Control Input. With CS low, the wiper position moves in the direction
determined by the state of U/D on a high-to-low transition.
56H
High Terminal of Resistor. The voltage at H can be greater than or less than the voltage at L.
Current can flow into or out of H.
62V
DD Power Supply
7 W Wiper Terminal of Resistor
—8 L
Low Terminal of Resistor. The voltage at L can be greater than or less than the voltage at H.
Current can flow into or out of L.
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
_______________________________________________________________________________________ 7
Detailed Description
The MAX5471/MAX5472/MAX5474/MAX5475 contain a
resistor array with 31 resistive elements (Figures 2 and
3). The MAX5471/MAX5474 have a total end-to-end
resistance of 50kΩ, and the MAX5472/MAX5475 have
an end-to-end resistance of 100kΩ. The MAX5471/
MAX5472 wiper is connected to the high terminal, and
the low terminal is internally connected to ground, mak-
ing the device a variable resistor. The MAX5474/
MAX5475 allow access to the high, low, and wiper ter-
minals for a standard voltage-divider configuration.
The wiper is moved among the 32 tap points through a
simple 3-wire interface. Nonvolatile memory allows the
wiper position to be stored and recalled to the same
point upon power-up.
Digital Interface
Logic inputs CS, U/D, and INC control the wiper posi-
tion and store it in nonvolatile memory (see the Truth
Table). The chip-select (CS) input enables the serial
interface when low and disables the interface when
high. The position of the wiper is stored when CS transi-
tions from low to high and INC is high (see the Storing
Wiper Position section).
With the serial interface active (CS low), a high-to-low
(falling edge) transition on INC moves the wiper posi-
tion by one resistive element in the direction deter-
mined by the state of U/D. If U/Dis high, the wiper
increments and it increases the resistance between W
and L (it decreases the resistance between H and W).
If U/Dis low, the wiper decrements and it decreases
the resistance between W and L (it increases the resis-
tance between H and W). The direction of the wiper
(state of U/D) can be changed at any time as long as
the setup and hold times are met.
Since the MAX5471/MAX5472 have the wiper internally
connected to H, an increment command increases the
resistance between H and GND, and a decrement com-
mand decreases the resistance between H and GND.
The wiper performs a make-before-break transition,
ensuring that there is never an open circuit during a
transition from one resistor tap to another. When the
wiper is at either end of the resistor array (max/min),
additional transitions in the direction of the endpoint do
not change the counter value (the wiper does not wrap
around).
Storing Wiper Position
The position of the wiper is stored in nonvolatile memo-
ry whenever CS transitions low-to-high (rising edge)
while INC is high. Upon power-up, the wiper returns to
this stored position. By keeping INC low while taking
CS high, the serial interface can be disabled and the
potentiometer placed in standby without storing the lat-
est wiper position. The factory-default wiper position
is midscale.
These devices can also be operated like a one-time
programmable (OTP) device. Once the desired wiper
position is trimmed and stored in nonvolatile memory,
disable the serial interface by connecting CS to VDD,
and INC to GND. The disabled interface places the
device in standby and disallows any changes to the
wiper position. In OTP mode, these devices become a
fixed 3-terminal potentiometer or a 1-terminal resistor to
GND with less than 1µA of supply current.
CS
VW
INC
tCYC
tCI tIL tIH
tID tDI
tIW
tIC tCPH
WIPER POSITION
STORED
WIPER POSITION
NOT STORED
tIK
NOTE: VW IS NOT A DIGITAL SIGNAL. IT REPRESENTS A WIPER TRANSITION.
tWSC
U/D
Figure 1. Digital Interface and Timing Diagram
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
8 _______________________________________________________________________________________
Standby Mode
The MAX5471/MAX5472/MAX5474/MAX5475 are
always in standby mode, except during the transition of
a logic input or while the wiper position is being stored.
When in standby mode, the static supply current is
reduced to less than 1µA and the resistive terminals (H,
W, and L) are unaffected.
Applications Information
The MAX5471/MAX5472/MAX5474/MAX5475 are
intended for circuits requiring digitally controlled
adjustable resistance, such as LCD contrast control
(where voltage biasing adjusts the display contrast), or
programmable filters with adjustable gain and/or cutoff
frequency.
Positive LCD Bias Control
Figures 4 and 5 show an application where the voltage-
divider or variable resistor is used to make an
adjustable, positive LCD-bias voltage. The op amp pro-
vides buffering and gain to the resistor-divider network
made by the potentiometer (Figure 4) or to a fixed
resistor and a variable resistor (Figure 5).
Programmable Filter
Figure 6 shows the configuration of a 1st-order pro-
grammable filter. The gain of the filter is adjusted by
R2, and the cutoff frequency is adjusted by R3. Use the
following equations to calculate the gain (G) and the
3dB cutoff frequency (fC):
G R
R
fRC
C
=+
=××
11
2
1
23π
CS U/DINC W
LLDecrement
LHIncrement
LXNo change
H X X No change
X X No change
X L Position not stored
X H Position stored
Truth Table
= High-to-low transition.
= Low-to-high transition.
X = Don’t care.
32-POSITION
DECODER
UP/DOWN
COUNTER
NONVOLATILE
MEMORY
VDD
GND
INC
H
5
2
6
3
4RW
CS 1
S32
S31
S30
S3
S2
S1
MAX5471
MAX5472
U/D
R31
R30
R2
R1
Figure 2. MAX5471/MAX5472 Functional Diagram
32-POSITION
DECODER
UP/DOWN
COUNTER
NONVOLATILE
MEMORY
VDD
GND
H
6
3
2
4
5RW
1
S32
S31
S30
S3
S2
S1
MAX5474
MAX5475
U/D
R31
R30
R2
R1
CS
INC 7W
8
L
Figure 3. MAX5474/MAX5475 Functional Diagram
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
_______________________________________________________________________________________ 9
MAX5474
MAX5475
30V
5V
H
W
L
VOUT
Figure 4. Positive LCD Bias Control Using a Voltage-Divider
MAX5471
MAX5472
30V
5V
H
GND
VOUT
Figure 5. Positive LCD Bias Control Using a Variable Resistor
MAX5471
MAX5472
MAX5471
MAX5472
H
GND
H
GND
VOUT
R1
R2
R3
C
VIN
Figure 6. Programmable Filter
Chip Information
TRANSISTOR COUNT: 5031
PROCESS: BiCMOS
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
10 ______________________________________________________________________________________
6L THIN SOT23.EPS
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
______________________________________________________________________________________ 11
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
MAX5471/MAX5472/MAX5474/MAX5475
32-Tap, Nonvolatile, Linear-Taper Digital
Potentiometers in SOT23
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2006 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
SOT23, 8L.EPS
0
0
PACKAGE OUTLINE, SOT-23, 8L BODY
21-0078 G 1
1
MARKING