Analog and Interface Products
Digital Potentiometers Design Guide
www.microchip.com/analog
Digital Potentiometer Solutions
Microchip’s Family of Digital Potentiometers
Microchip offers a wide range of devices that allow you to select the best fit for your application needs. Some of the
selection options include:
■
End-to-end resistance (R
ab
) values
• 2.1 kΩ to 100 kΩ (typical)
■
Resolution
• 6-bit (64 steps)
• 7-bit (128/129 steps)
• 8-bit (256/257 steps)
■
Serial interfaces
• Up/down
• SPI
• I
2
C
■
Memory types
• Volatile
• Non-volatile (EEPROM)
■
Resistor network configurations
• Potentiometer (voltage divider)
• Rheostat (variable resistor)
■
Single, dual and quad potentiometer options
■
Different package options
■
Special features
• Shutdown mode
• WiperLock™ technology
■
Low-power options
■
Low-voltage options (1.8V)
■
High-voltage options (36V or ±18V)
Microchip offers digital potentiometer devices with typical end-to-end resistances of 2.1 kΩ, 5 kΩ, 10 kΩ, 50 kΩ and
100 kΩ. These devices are available in 6, 7 or 8 bits of resolution.
The serial interface options allow you to easily integrate the device into your application. For some applications, the simple
up/down interface will be adequate. Higher-resolution devices (7-bit, 8-bit) often require direct read/write to the wiper
register. This is supported with SPI or I
2
C interfaces. SPI is simpler to implement, but I
2
C uses only two signals (pins) and
can support multiple devices on the serial bus without additional pins.
Microchip offers both volatile and non-volatile (EEPROM) devices,
allowing you the flexibility to optimize your system design. The
integrated EEPROM option allows you to save digital potentiometer
settings at power-down and restore to its original value and power-up.
Resistor network configurations allow the package size/cost to
be minimized for the desired functionality. For example, in the
MCP4017/18/19 family, if a variable resistor (rheostat) is desired,
the MCP4019 can be selected in a low-cost 5-pin SC70 package to
achieve the functionality.
In some applications, matched components are critical to ensure
system performance. Dual- and quad-digital potentiometer resistor
networks are manufactured on the same silicon and closely matched,
creating a good fit for these types of applications.
Packaging options allow you to address your system requirement
trade-offs including device cost, board area and manufacturing sites
(Surface mount vs. through-hole). Small form factors, such as tiny
SC70 packages, are available.
2
Digital Potentiometers Design Guide
Low-Power Applications
Low-Power Applications
Low power consumption has become more important in
recent years, especially in battery-powered applications.
Microchip’s digital potentiometer families are low power,
with the maximum I
dd
as low as 1
µA
in some devices.
This low current is possible when the serial interface is
inactive and a non-volatile memory write cycle is not active.
This low current does not include any current through the
resistor network (the A, B and W pins). The 1
µA
maximum
I
dd
devices are listed in the table below. Currently, all other
devices have a max I
dd
of 5
µA.
Many other devices are capable of shutting down the
resistor network, or disconnect the resistor network from
the circuit, in order to substantially reduce the current
through the digital potentiometer resistor network(s).
This shutdown mode may be achieved by a hardware pin
(SHDN) or via software through the Terminal Control (TCON)
register(s).
The hardware shutdown forces the resistor network
into a defined condition where the resistor network is
disconnected from the Terminal A pin and the Wiper value
is forced to 00h (Wiper connected to Terminal B). The
Wiper register retains its value so that when shutdown is
exited the wiper returns to its pervious position.
Normal vs. Shutdown Mode
“Normal” Mode
A
“Shutdown” Mode
A
W
W
B
B
The software shutdown allows control to each of the
resistor network terminal pins. Each resistor network has
4-bit in a TCON register. One bit for each terminal pin (A,
B and W) and one bit that mimics the hardware shutdown
state (the resistor network is disconnected from the
Terminal A pin and the Wiper value is forced to 00h).
The software shutdown is more flexible than the hardware
shutdown pin, as it allows devices to retain this capability
while being packaged in the smallest package where a
hardware shutdown pin (SHDN) was not implemented.
Low-Power Devices
R
ab
Resistance
kΩ (typ.)
Shutdown Mode
Zero-Scale/
Full-Scale
(2)
I
dd
Max. (µA)
(4)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Serial Interface
Voltage Range
# of Channels
Configuration
Memory Type
WiperLock™
Technology
Resolution
(# of steps)
MCP4011
(1)
MCP4012
(1)
MCP4013
(1)
MCP4014
(1)
MCP4021
(1)
MCP4022
(1)
MCP4023
(1)
U/D
U/D
U/D
U/D
U/D
U/D
U/D
U/D
SPI
SPI
SPI
SPI
SPI
SPI
Volatile
Volatile
Volatile
Volatile
EEPROM
EEPROM
EEPROM
EEPROM
Volatile
Volatile
Volatile
Volatile
Volatile
Volatile
64
64
64
64
64
64
64
64
256
256
256
256
256
256
2.1/5/10/50
2.1/5/10/50
2.1/5/10/50
2.1/5/10/50
2.1/5/10/50
2.1/5/10/50
2.1/5/10/50
2.1/5/10/50
10
50
100
10
50
100
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/N
(3)
Y/N
(3)
1
1
1
1
1
1
1
1
1
1
1
2
2
2
N
N
N
N
Y
Y
Y
Y
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Y
Y
Y
Pot
Rheo
Pot
(6)
Rheo
(6)
Pot
Rheo
Pot
(6)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
2.7V to 5.5V
8-pin SOIC, 8-pin
MSOP, 8-pin DFN
6-pin SOT-23
6-pin SOT-23
5-pin SOT-23
8-pin SOIC, 8-pin
MSOP, 8-pin DFN
6-pin SOT-23
6-pin SOT-23
5-pin SOT-23
8-pin PDIP, 8-pin SOIC
8-pin PDIP, 8-pin SOIC
8-pin PDIP, 8-pin SOIC
14-pin PDIP 14-pin
,
SOIC, 14-pin TSSOP
14-pin PDIP 14-pin
,
SOIC, 14-pin TSSOP
14-pin PDIP 14-pin
,
SOIC, 14-pin TSSOP
MCP4024
(1)
MCP41010
MCP41050
MCP41100
MCP42010
MCP42050
MCP42100
Rheo
(6)
Pot
Pot
Pot
Pot
Pot
Pot
Y/N
(3)
Y/N
(3)
Y/N
(3)
Y/N
(3)
1. Resistor options are: −202 (2.1 kΩ), −502 (5.0 kΩ), −103 (10.0 kΩ) and −503 (50.0 kΩ).
2. Zero-scale allows the wiper to “directly” connect to Terminal B, while full-scale allows the wiper to “directly” connect to Terminal A.
3. There is one R
s
resistor between the maximum wiper value and Terminal A.
4. This current is with the serial interface inactive, and not during an EEPROM write cycle (for non-volatile devices).
5. The serial interface has been tested to 1.8V, the device’s analog characteristics (resistor) have been tested from 2.7V to 5.5V. Review the device’s characterization graphs for information on analog
performance between 1.8V and 2.7V.
6. One of the terminal pins (A or B) is internally connected to ground, due to the limitation of the number of pins on the package.
Packages
Device
Digital Potentiometers Design Guide
3
Low-Voltage Applications
Low-Voltage Applications
Some applications require a low operating voltage. Microchip offers most of the volatile memory devices and some of the
non-volatile devices specified down to 1.8V for their digital operation. The analog performance between 1.8V and 2.7V is
not specified, but is characterized and can be found in the device’s characterization graphs for more information.
Low-Voltage Devices (1.8V)
R
ab
Resistance
kΩ (typ.)
Shutdown Mode
Zero-Scale/
Full-Scale
(2)
I
dd
Max. (µA)
(4)
1
1
1
1
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
Serial Interface
Voltage Range
# of Channels
Configuration
Memory Type
WiperLock™
Technology
Resolution
(# of steps)
Device
MCP4011
(1)
MCP4012
(1)
MCP4013
(1)
U/D
U/D
U/D
U/D
I
2
C
IC
2
Volatile
Volatile
Volatile
Volatile
Volatile
Volatile
Volatile
Volatile
Volatile
Volatile
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
64
64
64
64
128
128
128
128
128
128
129
129
129
129
257
257
257
257
129
129
129
129
257
257
257
2.1/5/10/50
2.1/5/10/50
2.1/5/10/50
2.1/5/10/50
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
Y
Y
N
N
Y
Y
N
N
Y
N
N
N
N
N
N
N
N
N
N
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Pot
Rheo
Pot
(6)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
8-pin SOIC, 8-pin MSOP,
8-pin DFN
6-pin SOT-23
6-pin SOT-23
5-pin SOT-23
6-pin SC70
6-pin SC70
5-pin SC70
6-pin SC70
6-pin SC70
5-pin SC70
8-pin PDIP, 8-pin SOIC,
8-pin MSOP, 8-pin DFN
8-pin PDIP, 8-pin SOIC,
8-pin MSOP, 8-pin DFN
8-pin PDIP, 8-pin SOIC,
8-pin MSOP, 8-pin DFN
8-pin PDIP, 8-pin SOIC,
8-pin MSOP, 8-pin DFN
8-pin PDIP, 8-pin SOIC,
8-pin MSOP, 8-pin DFN
8-pin PDIP, 8-pin SOIC,
8-pin MSOP, 8-pin DFN
8-pin PDIP, 8-pin SOIC,
8-pin MSOP, 8-pin DFN
8-pin PDIP, 8-pin SOIC,
8-pin MSOP, 8-pin DFN
14-pin PDIP, 14-pin SOIC,
14-pin TSSOP, 16-pin QFN
10-pin MSOP, 10-pin DFN
14-pin PDIP, 14-pin SOIC,
14-pin TSSOP, 16-pin QFN
10-pin MSOP, 10-pin DFN
14-pin PDIP, 14-pin SOIC,
14-pin TSSOP, 16-pin QFN
10-pin MSOP, 10-pin DFN
14-pin PDIP, 14-pin SOIC,
14-pin TSSOP, 16-pin QFN
MCP4014
(1)
MCP4017
(2)
MCP4018
(2)
Rheo
(6)
Rheo
Pot
(6)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
MCP4019
(2)
MCP40D17
(2)
MCP40D18
(2)
I
2
C
I
2
C
IC
2
Rheo
(6)
Rheo
Pot
(6)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
MCP40D19
(2)
MCP4131
(2)
MCP4132
(2)
MCP4141
(2)
MCP4142
(2)
MCP4151
(2)
MCP4152
(2)
MCP4161
(2)
MCP4162
(2)
MCP4231
(2)
MCP4232
(2)
MCP4241
(2)
MCP4242
(2)
MCP4251
(2)
MCP4252
(2)
MCP4261
(2)
1.
2.
3.
4.
5.
I
2
C
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
Rheo
(6)
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
Resistor options are: −202 (2.1 kΩ), −502 (5.0 kΩ), −103 (10.0 kΩ) and −503 (50.0 kΩ).
Resistor options are: −502 (5.0 kΩ), −103 (10.0 kΩ), 503 (50.0 kΩ), and −104 (100.0 kΩ).
Zero-scale allows the wiper to “directly” connect to Terminal B, while full-scale allows the wiper to “directly” connect to Terminal A.
This current is with the serial interface inactive, and not during an EEPROM write cycle (for non-volatile devices).
The digital serial interface has been tested to 1.8V but the device’s analog characteristics have only been specified from 2.7V to 5.5V. Review the device’s characterization graphs for information on
analog performance between 1.8V and 2.7V.
6. One of the terminal pins (A or B) is internally connected to ground, due to the limitation of the number of pins on the package.
7. Shutdown support via software (TCON register(s)). If device has SHDN pin, software shutdown also functions.
4
Digital Potentiometers Design Guide
Packages
Low-Voltage Applications
Low-Voltage Devices (1.8V) (Continued)
R
ab
Resistance
kΩ (typ.)
Shutdown Mode
Zero-Scale/
Full-Scale
(2)
I
dd
Max. (µA)
(4)
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
Serial Interface
Voltage Range
# of Channels
Configuration
Memory Type
WiperLock™
Technology
Resolution
(# of steps)
Device
MCP4262
(2)
MCP4331
(2)
MCP4332
(2)
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
SPI
I
2
C
I
2
C
IC
2
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
Volatile
Volatile
EEPROM
EEPROM
257
129
129
129
129
257
257
257
257
129
129
129
129
257
257
257
257
129
129
129
129
257
257
257
257
129
129
129
129
257
257
257
257
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
5/10/50/100
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
Y/Y
2
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
Y
N
N
Y
Y
N
N
Y
Y
N
N
Y
Y
N
N
Y
Y
N
N
Y
Y
N
N
Y
Y
N
N
Y
Y
N
N
Y
Y
Y
(7)
Y
(7)
Y
(7)
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
Pot
Rheo
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
10-pin MSOP, 10-pin DFN
20-pin TSSOP, 20-pin QFN
14-pin TSSOP
20-pin TSSOP, 20-pin QFN
14-pin TSSOP
20-pin TSSOP, 20-pin QFN
14-pin TSSOP
20-pin TSSOP, 20-pin QFN
14-pin TSSOP
20-pin TSSOP, 20-pin QFN
14-pin TSSOP
20-pin TSSOP, 20-pin QFN
14-pin TSSOP
20-pin TSSOP, 20-pin QFN
14-pin TSSOP
20-pin TSSOP, 20-pin QFN
14-pin TSSOP
8-pin MSOP, 8-pin DFN
8-pin MSOP, 8-pin DFN
8-pin MSOP, 8-pin DFN
8-pin MSOP, 8-pin DFN
8-pin MSOP, 8-pin DFN
8-pin MSOP, 8-pin DFN
8-pin MSOP, 8-pin DFN
8-pin MSOP, 8-pin DFN
14-pin TSSOP 16-pin QFN
,
10-pin MSOP, 10-pin DFN
14-pin PDIP, 14-pin SOIC,
14-pin TSSOP, 16-pin QFN
10-pin MSOP, 10-pin DFN
14-pin TSSOP 16-pin QFN
,
10-pin MSOP, 10-pin DFN
14-pin PDIP, 14-pin SOIC,
14-pin TSSOP, 16-pin QFN
10-pin MSOP, 10-pin DFN
MCP4341
(2)
MCP4342
(2)
MCP4351
(2)
Y
(7)
Y
(7)
Y
(7)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
MCP4352
(2)
MCP4361
(2)
MCP4362
(2)
Y
(7)
Y
(7)
Y
(7)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
MCP4431
(2)
MCP4432
(2)
MCP4441
(2)
Y
(7)
Y
(7)
Y
(7)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
MCP4442
(2)
MCP4451
(2)
MCP4452
(2)
MCP4461
(2)
MCP4462
(2)
MCP4531
(2)
MCP4532
(2)
MCP4541
(2)
MCP4542
(2)
MCP4551
(2)
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
IC
2
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
MCP4552
(2)
MCP4561
(2)
MCP4562
(2)
I
2
C
I
2
C
IC
2
Y
(7)
Y
(7)
Y
(7)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
MCP4631
(2)
MCP4632
(2)
MCP4641
(2)
MCP4642
(2)
MCP4651
(2)
MCP4652
(2)
MCP4661
(2)
MCP4662
(2)
1.
2.
3.
4.
5.
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
I
2
C
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
Y
(7)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
1.8V to 5.5V
(5)
Resistor options are: −202 (2.1 kΩ), −502 (5.0 kΩ), −103 (10.0 kΩ) and −503 (50.0 kΩ).
Resistor options are: −502 (5.0 kΩ), −103 (10.0 kΩ), 503 (50.0 kΩ), and −104 (100.0 kΩ).
Zero-scale allows the wiper to “directly” connect to Terminal B, while full-scale allows the wiper to “directly” connect to Terminal A.
This current is with the serial interface inactive, and not during an EEPROM write cycle (for non-volatile devices).
The digital serial interface has been tested to 1.8V but the device’s analog characteristics have only been specified from 2.7V to 5.5V. Review the device’s characterization graphs for information on
analog performance between 1.8V and 2.7V.
6. One of the terminal pins (A or B) is internally connected to ground, due to the limitation of the number of pins on the package.
7. Shutdown support via software (TCON register(s)). If device has SHDN pin, software shutdown also functions.
Packages
Digital Potentiometers Design Guide
5