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Potentiometer Introduction


Potentiometer is a typical contact type absolute angle sensor.

What is Potentiometer

Potentiometer is a typical contact type absolute angle sensor. It has a sliding contact on the resistance film (including carbon resistance film, conductive plastic film, metal resistance film, conductive ceramic film, etc.). By external action, the position of the contact point is changed so as to change the ratio of the upper and lower resistance of the resistance film, and the output voltage changes with the external position. Potentiometer is composed of electronic components and cursors. Cursors can slide on the surface of components, including linear sliding type and rotary type. The former is used to detect linear displacement, the latter is used to detect angle, tilt angle, etc. Obviously, pressure, weight, flow, etc. can be changed into mechanical displacement first, and then converted into electrical signal through potentiometer.

Potentiometer datasheet

Potentiometer Pinout &Configuration

Potentiometer has threeterminals, as shown in the table.

Pin No.Pin NameDescription
1Fixed EndThis end is connected to one end of the resistive track
2Variable EndThis end is connected to the wiper, to provide variable voltage
3Fixed EndThis end is connected to another end of the resistive track

Potentiometer Features

  1. Type: Rotary a.k.a Radio POT
  2. Available in different resistance values like 500Ω, 1K, 2K, 5K, 10K, 22K, 47K, 50K, 100K, 220K, 470K, 500K, 1 M. 
  3. Power Rating: 0.3W
  4. Maximum Input Voltage: 200Vdc
  5. Rotational Life: 2000K cycles

How does a potentiometer work?

As far as we know, resistors should always have two terminals, but why a potentiometer has three terminals, and how to use these terminals. It’s easy to understand the purpose of these terminals by looking at the chart below.


The figure shows the parts inside the potentiometer. We have a resistance track whose complete resistance will be equal to the rated resistance of the pot. As the symbol shows, a potentiometer is nothing more than a variable resistor at one end. Suppose a 10k potentiometer, if we measure the resistance between terminal 1 and terminal 3, we will get a 10k value, because both terminals are fixed ends of the potentiometer. Now, as shown in the figure above, let’s put the wiper 25% away from terminal 1. If we measure the resistance between terminal 1 and terminal 2, we will get 25% of 10km, i.e. 2.5km. If we measure the resistance between terminal 2 and terminal 3, we will get 7.5km.

Therefore, terminals 1 and 2 or 2 and 3 can be used to obtain variable resistance, or knobs can be used to change the resistance and set the required value.

Potentiometer Circuit


Potentiometer Applications

  • Voltage and Current Control Circuits
  • Used as volume control knobs in radios
  • Tuning or controlling circuits
  • Analog input control knobs

That’s all for today. Hope you enjoyed this article. However, if you have doubts or have any questions about this, you can contact me in the comments section below. I’ll be happy to help you as best I can. Let us know your feedback and suggestions at any time, they allow us to provide you with high-quality work that responds to your needs and expectations, and helps you continue to give back to our products. Thank you for reading this article.


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