A potentiometer is a device that is used to control the current flow. It consists of three terminals through which it achieves that objective. They consist of a sliding or rotating contact that creates an adjustable voltage divider. If only two of the three terminals are used, it acts as a rheostat. Potentiometers are majorly known as voltage dividers as they are designed to measure the voltage.
Potentiometers are primarily used to control devices like audio equipment or volume control. When operated by such a mechanism, they can also be used as transducers in a joystick device. They are rarely used to control significant amounts of power since the power that a potentiometer dissipates can be compared to the power in the control load.
How Does a Potentiometer Work?
- A potentiometer is also known as a pot. It consists of a resistive element known as a track and a sliding contact known as the wiper present internally in the area in which the end terminals are connected to the resistive element.
- The wiper is movable, and the resistance is then adjusted to it as it touches a resistive strip of material when it is moved closer to terminal 1 and moved far from terminal 2; the resistance at terminal 1 decreases, and the resistance at terminal 2 increases and vice versa.
- Then input voltage is provided across the resistor where the output voltage will indicate a drop between the sliding and the fixed contact.
- They measure the voltage with accuracy and reliability to accomplish a variable voltage from a fixed voltage source.
- Potentiometers are known as passive devices, which indicates that they do not need any additional power supply or circuits to operate.
- Some common examples of potentiometers include:
- Controlling the audio equipment with the help of using volume controls
- Measuring the position on a joystick for gaming.
Types of Potentiometers
There are many types of potentiometers in the market. Some are adjustable, while some are electronically controlled. We will mention the main kinds of potentiometers known in the market.
Rotatory potentiometers are the most common ones known and used in the market, where the adjustable wiper moves in a circular motion with the help of a knob. It consists of two pins connected to a resistive element put in a semi-circular element, while the other is connected to a rotatory knob. They have tolerances of 10% and 20% and can create linear or logarithmic outputs. There are various types of rotatory potentiometers which are:
- Dual-gang Pot
- Concentric pot
- Servo pot
Linear potentiometers are also known as sliders or faders. They are similar to the rotatory potentiometer, but the wiper moves in a linear motion in a linear potentiometer rather than a circular one. It consists of a pin connected to an adjustable slider; two other pins are connected to both of the ends of the output circuit, where the slider can slide on the resistor with the help of a connected track to the resistor. The linear potentiometer family has various types that are:
- Slide Pot
- Multi-Turn Slide
- Dual-Slide Pot
- Motorized Fader
A digital potentiometer is more like an electronically controlled component similar to potentiometers in terms of analog functions. It consists of 3 terminals in which 2 pins are connected to the end terminals, and the last of these pins are found attached to the wiper terminal so that the output voltage can vary. These potentiometers are popular due to their small size, no moving part, reliability, tolerance up to ±1%, and resistance to environmental conditions.