• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer

Electrical Engineering News and Products

Electronics Engineering Resources, Articles, Forums, Tear Down Videos and Technical Electronics How-To's

  • Products / Components
    • Analog ICs
    • Battery Power
    • Connectors
    • Microcontrollers
    • Power Electronics
    • Sensors
    • Test and Measurement
    • Wire / Cable
  • Applications
    • 5G
    • Automotive/Transportation
    • EV Engineering
    • Industrial
    • IoT
    • Medical
    • Telecommunications
    • Wearables
    • Wireless
  • Learn
    • eBooks / Handbooks
    • EE Training Days
    • Tutorials
    • Learning Center
    • Tech Toolboxes
    • Webinars & Digital Events
  • Resources
    • White Papers
    • Design Guide Library
    • Digital Issues
    • Engineering Diversity & Inclusion
    • LEAP Awards
    • Podcasts
    • DesignFast
  • Videos
    • EE Videos and Interviews
    • Teardown Videos
  • EE Forums
    • EDABoard.com
    • Electro-Tech-Online.com
  • Bill’s Blogs
  • Advertise
  • Subscribe

What is a digital potentiometer?

January 12, 2017 By Janet Heath

A digital potentiometer (or “digipot”) operates like a traditional mechanical potentiometer (pot), which is a variable resistor, except the digipot is an integrated chip (IC) that accepts signal input rather than the physical movement of a shaft or slide for adjustment. Essentially, both types of potentiometer are analog devices that provide variable resistance. However, a mechanical pot is an adjustable voltage divider by means of an adjustable slider or rotary resistor. Pots physically change the resistance value whereas digipots modify the resistance value via digital inputs rather than a physical slider or rotary wheel. As the shaft of the mechanical pot is turned, the center pin, called a “wiper,” moves and changes the resistance on either site of the wiper.

Figure 1: Simplified schematic, or functional block diagram, of a Texas Instruments TPL0102 dual digital potentiometer. (Image Source: ti.com)

Why digital potentiometers?

Digipots are convenient for use where environmental factors can adversely affect a mechanical pot. Environments with vibration or particles like dirt, dust, moisture or grease that can gum up the shaft can drive one to choose a digital potentiometer. Digipots can be better protected from the environment since they can be encapsulated. Digipots are less vulnerable to vibration, less accessible to physical tampering, and can offer more features (being an IC) than a mechanical pot. Additional options for digipots can include a quad-pack of digipots in a single package, shutdown mode, and programmable pre-set positions upon power-on for the wiper. Digipots can use memory (both volatile and non-volatile) for a set wiper position upon start-up. They can eliminate the irritation of mounting a mechanical device to a printed circuit board (PCB), as well. Digital potentiometers are adjusted via writing to the digipot’s digital inputs to set the “wiper,” therefore they do not require physical access.

Digipots can also offer higher resolution, greater stability, and solid-state reliability. They are smaller than mechanical potentiometers and can fit in tiny IC packages measuring 2.9 mm x 2.8 mm (SOT-23-6) or smaller. On the downside, digipots can be more complicated as they must be programmed, typically with I2C or SPI communication bus protocols. Digital potentiometers can be made with just 1% end-to-end resistance tolerance. The resolution of digital potentiometers has improved to the point that a digipot can replace digital-to-analog converters in some cases. Both DACs and digipots produce an analog output signal in response to a digital input signal. With digital pots, the wiper is the analog output. The important differences, however, are that DACs can have a higher resolution and DACs include an output buffer amplifier, whereas digital pots do not.[i]

Applications

Digital potentiometers can be used where ever mechanical potentiometers are employed,[ii] for sensor trimming and calibration (remote or local), instrumentation (gain or offset adjustment), for adjustable gain amplifiers, audio level control, to match line impedances, in optical networks, for level adjustments in automotive electronics and in programmable power supplies, filters, time constants, or delay values. Another fundamental function of any potentiometer is the ability to use just two of the three terminals, and thus create a rheostat.

 

[i] “DACs vs. Digital Potentiometers: Which Is Right for My Application?” TUTORIAL 4025. Maxim Integrated, 11 Apr. 2007. Web. 6 Jan. 2017.

[ii] “Digital Potentiometers Replace Mechanical Potentiometers …” Tutorial 3417. Maxim Integrated, 21 Dec. 2004. Web. 6 Jan. 2017.

 

The post What is a digital potentiometer? appeared first on Analog IC Tips.

You Might Also Like

Filed Under: Analog IC Tips, FAQ, Featured

Primary Sidebar

EE Engineering Training Days

engineering

Featured Contributions

Five challenges for developing next-generation ADAS and autonomous vehicles

Robust design for Variable Frequency Drives and starters

Meeting demand for hidden wearables via Schottky rectifiers

GaN reliability milestones break through the silicon ceiling

From extreme to mainstream: how industrial connectors are evolving to meet today’s harsh demands

More Featured Contributions

EE Tech Toolbox

“ee
Tech Toolbox: Internet of Things
Explore practical strategies for minimizing attack surfaces, managing memory efficiently, and securing firmware. Download now to ensure your IoT implementations remain secure, efficient, and future-ready.

EE Learning Center

EE Learning Center
“ee
EXPAND YOUR KNOWLEDGE AND STAY CONNECTED
Get the latest info on technologies, tools and strategies for EE professionals.
“bills

R&D World Podcasts

R&D 100 Episode 10
See More >

Sponsored Content

Advanced Embedded Systems Debug with Jitter and Real-Time Eye Analysis

Connectors Enabling the Evolution of AR/VR/MR Devices

Award-Winning Thermal Management for 5G Designs

Making Rugged and Reliable Connections

Omron’s systematic approach to a better PCB connector

Looking for an Excellent Resource on RF & Microwave Power Measurements? Read This eBook

More Sponsored Content >>

RSS Current EDABoard.com discussions

  • need of carrier supression when locking to cavity resonator
  • Reducing "shoot-through" in offline Full Bridge SMPS?
  • What is the purpose of using a VCVS?
  • Checking line impedance
  • Why do I hear whistling sounds in my vents?

RSS Current Electro-Tech-Online.com Discussions

  • Wideband matching an electrically short bowtie antenna; 50 ohm, 434 MHz
  • Why can't I breadboard this oscillator?
  • Failure of polypropylene motor-run capacitors
  • a point I can't understand about the sinc expression
  • Quick advice on remote car starter?
Search Millions of Parts from Thousands of Suppliers.

Search Now!
design fast globle

Footer

EE World Online

EE WORLD ONLINE NETWORK

  • 5G Technology World
  • Analog IC Tips
  • Battery Power Tips
  • Connector Tips
  • DesignFast
  • EDABoard Forums
  • Electro-Tech-Online Forums
  • Engineer's Garage
  • EV Engineering
  • Microcontroller Tips
  • Power Electronic Tips
  • Sensor Tips
  • Test and Measurement Tips

EE WORLD ONLINE

  • Subscribe to our newsletter
  • Teardown Videos
  • Advertise with us
  • Contact us
  • About Us

Copyright © 2025 · WTWH Media LLC and its licensors. All rights reserved.
The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media.

Privacy Policy