A potentiometer, often referred to as a "pot," is a type of variable resistor used to control the flow of electric current in a circuit. It consists of a resistive element with three terminals: two fixed outer terminals and one movable center terminal.
The resistive element can take various shapes, but commonly, it is a long, thin strip or a coiled wire made of a resistive material such as carbon or conductive plastic. The two outer terminals are connected to the ends of the resistive element, and the movable center terminal, also called the wiper, makes contact with the resistive element and can slide along its length.
By adjusting the position of the wiper along the resistive element, the potentiometer can provide a variable resistance between the two outer terminals. This property allows it to act as a voltage divider in a circuit, meaning it can produce an output voltage that is a fraction of the input voltage.
Potentiometers are commonly used for various applications, including:
Volume control in audio devices: Turning the knob on a speaker or amplifier changes the potentiometer's resistance, adjusting the volume.
Dimmer switches for lights: In this case, the potentiometer is used to control the brightness of the light.
Control inputs for electronic circuits: Potentiometers can be used as user-adjustable control inputs for devices like robotics, motor control, and instrumentation.
Calibration and tuning: Potentiometers are used in some electronic circuits for calibration and fine-tuning purposes.
There are both single-turn and multi-turn potentiometers available, depending on the required precision and range of adjustment. Additionally, there are digital potentiometers that offer a similar function but can be controlled electronically using digital signals.
It's essential to note that potentiometers are not meant for high-power applications, as they have relatively limited power handling capabilities compared to other types of resistors.