19-1435; Rev 2a; 2/01
Low-Power Digital Potentiometers
General Description
The MAX5160/MAX5161 linear-taper digital potentiome-
ters perform the same function as a mechanical poten-
tiometer or a variable resistor. They consist of a fixed
resistor and a wiper contact with 32 tap points that are
digitally controlled by three lines for the 8-pin MAX5160
or by two lines for the 6-pin MAX5161.
These parts are ideal for applications requiring digitally
controlled resistors. Three resistance values are avail-
able for each part type: 50kΩ, 100kΩ, and 200kΩ. A
nominal resistor temperature coefficient of 50ppm/°C
end-to-end and only 5ppm/°C ratiometric makes the
MAX5160 ideal for applications requiring a low-temper-
ature-coefficient variable resistor, such as low-tempco,
adjustable-gain circuit configurations.
The MAX5160 is available in an 8-pin µMAX package,
and the MAX5161 is available in a 6-pin SOT23 pack-
age. Both devices are guaranteed over the extended-
industrial temperature range (-40°C to +85°C).
o
32 Tap Positions
o
50kΩ, 100kΩ, and 200kΩ Resistance Values
o
400Ω Wiper Resistance
o
±25% Resistance Tolerance
o
3-Wire Serial Data Input
o
±1LSB DNL
o
±0.5LSB INL
o
100nA Supply Current
o
+2.7V to +5.5V Single-Supply Operation
o
Power-On Reset: Wiper Goes to Midscale
(position 16)
o
±2kV ESD Protection
o
Small-Footprint Packages
6-Pin SOT23 (MAX5161)
8-Pin µMAX (MAX5160)
o
Glitchless Switching Between the Resistor Taps
Features
MAX5160/MAX5161
Applications
LCD Screen Adjustment
Volume Control
Mechanical Potentiometer Replacement
Ordering Information
PART
MAX5160NEUA
MAX5160MEUA
MAX5160LEUA
MAX5161NEZT
MAX5161MEZT
MAX5161LEZT
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
8 µMAX
8 µMAX
8 µMAX
6 SOT23
6 SOT23
6 SOT23
R
(kΩ)
200
100
50
200
100
50
R
(kΩ)
200
100
50
200
100
50
Selector Guide
PART
MAX5160NEUA
MAX5160MEUA
MAX5160LEUA
MAX5161NEZT
MAX5161MEZT
MAX5161LEZT
TOP
MARK
—
—
—
AAAC
AAAB
AAAA
Functional Diagram
H
V
DD
GND
Pin Configurations
TOP VIEW
L
1
INC
U/D
H
GND
1
2
3
4
8
V
DD
CS
L
W
GND
3
4
U/D
H
2
7
6
5
6
V
DD
CS
INC
U/D
UP/DN
COUNTER
POSITION
DECODER
MAX5160
MAX5161
MAX5160
MAX5161
5
INC
W
µMAX
SOT23-6
L
________________________________________________________________Maxim
Integrated Products
1
For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
Low-Power Digital Potentiometers
MAX5160/MAX5161
ABSOLUTE MAXIMUM RATINGS
V
DD
to GND ..............................................................-0.3V to +6V
CS, INC,
U/D to GND ...............................................-0.3V to +6V
H, L, W to GND.......................................... -0.3V to (V
DD
+ 0.3V)
Input and Output Latchup Immunity ..............................±200mA
Maximum Continuous Current into H, L, and W
MAX516_ _ E_ _...............................................................±1mA
Continuous Power Dissipation (T
A
= +70°C)
6-Pin SOT23 (derate 6.25mW/°C above +70°C)...........500mW
8-Pin µMAX (derate 4.1mW/°C above +70°C) ..............330mW
Operating Temperature Range .......................... -40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) ................................+300° C
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.
ELECTRICAL CHARACTERISTICS
(V
DD
= +2.7V to +5.5V, V
H
= V
DD
, V
L
= 0, T
A
= T
MIN
to T
MAX
. Typical values are at V
DD
= +5V, T
A
= +25°C, unless otherwise noted.)
PARAMETER
DC PERFORMANCE
Resolution
Integral Nonlinearity (Note 1)
Differential Nonlinearity (Note 1)
End-to-End Resistor Tempco
Ratiometric Resistor Tempco
Full-Scale Error
Zero-Scale Error
Wiper Resistance
Wiper Capacitance
End-to-End Resistance
DIGITAL INPUTS
Input High Voltage
Input Low Voltage
Input Leakage Current
Input Capacitance
TIMING CHARACTERISTICS
(Figure 6)
CS
to
INC
Setup Time
CS
to
INC
Hold Time
INC
Low Period
INC
High Period
U/D to
INC
Hold
U/D to
INC
Setup
Wiper-Settling Time
INC
Frequency
POWER SUPPLIES
Supply Voltage
Supply Current
V
DD
I
DD
CS
=
INC
= U/D =
V
DD
or GND
V
DD
= +5V
V
DD
= +2.7V
2.7
0.6
135
5.5
10
V
µA
nA
t
CI
t
IC
t
IL
t
IH
t
ID
t
DI
t
IW
f
IMAX
25
0
25
25
0
50
1
7
ns
ns
ns
ns
ns
ns
µs
MHz
5
V
IH
V
IL
0.7
✕
V
DD
0.3
✕
V
DD
±1
V
V
µA
pF
R
W
C
W
MAX516_NE_ _
HL
MAX516_ME_ _
MAX516_LE_ _
150
75
37.5
400
10
200
100
50
250
125
62.5
kΩ
INL
DNL
TC
R
50
5
-0.1
+0.1
1700
3
±1/2
±1
%
LSB
LSB
ppm/°C
ppm/°C
LSB
LSB
Ω
pF
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Note 1:
For the MAX5160, linearity is defined in terms of H to L code-dependent resistance.
2
_______________________________________________________________________________________
Low-Power Digital Potentiometers
Typical Operating Characteristics
(V
DD
= +5V, T
A
= +25°C, unless otherwise noted.)
WIPER RESISTANCE
vs. WIPER VOLTAGE
MAX5160/61 toc01
MAX5160/MAX5161
END-TO-END RESISTANCE % CHANGE
vs. TEMPERATURE
END-TO-END RESISTANCE % CHANGE
0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
-0.10
-0.12
-0.14
-0.16
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
TEMPERATURE (°C)
50kΩ
200kΩ
100kΩ
100kΩ
200kΩ 50kΩ
MAX5160/61 toc02
1,000
R
WMAX
= 574.0804
800
WIPER RESISTANCE (Ω)
V
DD
= +2.7V
0.06
600
400
V
DD
= +5V
200
0
0
1
2
3
4
5
WIPER VOLTAGE (V)
END-TO-END RESISTANCE
vs. TAP POSITION
MAX5160/61 toc03
END-TO-END RESISTANCE
vs. TAP POSITION
100
90
80
RESISTANCE (kΩ)
70
60
50
40
30
20
10
0
1
5
9
13
17
21
25
29
33
TAP POSITION
100kΩ
MAX5160/61 toc04
225
200
175
RESISTANCE (kΩ)
150
125
100
75
50
25
0
1
5
9
13
17
21
25
29
200kΩ
110
33
TAP POSITION
END-TO-END RESISTANCE
vs. TAP POSITION
45
40
RESISTANCE (kΩ)
35
30
25
20
15
10
5
0
1
5
9
13
17
21
25
29
33
TAP POSITION
50kΩ
MAX5160/61 toc05
50
_______________________________________________________________________________________
3
Low-Power Digital Potentiometers
MAX5160/MAX5161
Typical Operating Characteristics (continued)
(V
DD
= +5V, T
A
= +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. TEMPERATURE
0.8
SUPPLY CURRENT (µA)
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-40
-20
0
20
40
60
80
100
V
DD
= +2.7V
INC
2V/div
0V
0V
V
DD
= +5V
MAX5160/61 toc06
TAP-TO-TAP SWITCHING TRANSIENT
OUTPUT
W
50mV/div
MAX5160/61 toc07
0.9
5µs/div
TEMPERATURE (°C)
Pin Description
PIN
MAX5160
1
PIN
NAME
MAX5161
5
INC
Wiper Increment Control Input. With
CS
low, a high-to-low transition increments
(U/D high) or decrements (U/D low) the wiper position.
Up/Down Control Input. With
CS
low, a high-to-low
INC
transition increments
(U/D high) or decrements (U/D low) the wiper position.
High Terminal of Resistor
Ground
Wiper Terminal of Resistor
Low Terminal of Resistor
Chip-Select Input. Drive low to change the wiper position through
INC
and U/D.
Power Supply
FUNCTION
2
3
4
5
6
7
8
4
2
3
—
1
—
6
U/D
H
GND
W
L
CS
V
DD
4
_______________________________________________________________________________________
Low-Power Digital Potentiometers
Detailed Description
The MAX5160/MAX5161 consist of resistor arrays with
thirty-one resistive elements. Thirty-two tap points are
accessible to the wiper along the resistor string
between H and L. Logic inputs
CS,
U/D, and
INC
determine the position of the wiper. With
CS
low and
U/D high, a high-to-low transition on
INC
increments the
internal counter, increasing the resistance between W
and L. When both
CS
and U/D are low, a high-to-low
INC
transition decrements the internal counter, decreas-
ing the resistance between W and L. At either end
(maximum or minimum positions), additional transitions in
the direction of the end points will not change the counter
value (the counter will not wrap around).
The H and L terminals of the MAX5160 are similar to the
two end terminals of a mechanical potentiometer. The
tap W is equivalent to the variable tap (wiper) of the
potentiometer.
The MAX5161 is similar to the MAX5160 except that
CS
internally connects to ground and the wiper terminal (W)
is shorted to the high terminal (H). The MAX5161 acts as
a variable resistor (a potentiometer with the wiper and
one end terminal shorted together).
The MAX5160/MAX5161 feature power-on reset circuit-
ry that sets the wiper position to midscale at power-up.
MAX5160/MAX5161
Applications Information
The MAX5160/MAX5161 are intended for circuits
requiring digitally controlled adjustable voltage or
adjustable gain, such as LCD contrast control, where
voltage biasing adjusts the display contrast.
Controlling a Switch-Mode
LCD Bias Generator
Figure 1 shows an application where the MAX5161 is
used with a MAX1771 to make an adjustable positive
LCD-bias circuit. The output of the MAX1771 is a posi-
tive voltage that is digitally controlled through the
MAX5160/MAX5161. Similarly, Figure 2 shows the
application of the MAX5161 in a digitally controlled
negative LCD-bias circuit along with the MAX774/
MAX775/MAX776.
V
IN
= 5V
C1
68µF
C2
0.1µF
2
V+
5 REF
C3
0.1µF
4 SHDN
MAX1771
6 AGND
1
L1
22µH
D1
1N5817-22
N
MTD20N03HDL
R
SENSE
40mΩ
C4
300µF
V
OUT
= 12V
AT 0.5A
V
IN
C1
150µF
C2
0.1µF
R2
MAX5161
1 OUT
3
2
FB
R
VAR
1N5822/
MBR340
REF
GND
8
L1
22µH
C4
*
SHDN
MAX774
V+
5
R3
0.07Ω
Q1
Si9435
P
MAX775
CS 6
MAX776
7
EXT
EXT
V
OUT
CS
8
R1
R2
C3
0.1µF
C5
R
VAR
4
FB
GND
7
3
MAX5161
R1
V
REF
= 1.5V
*
MAX774 = 330µF, 10V
MAX775, MAX776 = 120µF, 20V
V
OUT(MAX)
R2
=
+1
R1
V
REF
V
OUT(MIN)
R2
=
R1 + R
VAR(MAX)
V
REF
V
OUT(MAX)
R2 V
OUT(MIN)
R2
=
,
=
R1
V
REF
R1 + R
VAR
V
REF
V
REF
- V
FB
≥
5µA (FOR 2% GAIN-SETTING ACCURACY)
R1 + R
VAR
+1
(
)
Figure 1. Adjustable Positive LCD Bias
Figure 2. Adjustable Negative LCD Bias
5
_______________________________________________________________________________________
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