Potentiometer

Electronic-Component-Potentiometer

A potentiometer is a three-terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider. If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat.

History

The potentiometer was invented by Johann Christian Poggendorff in the 19th century. It was initially used for measuring electrical potential (voltage) in circuits.

Construction

A potentiometer typically consists of a resistive element, a sliding contact (wiper) that moves along the element, and three terminals. The resistive element can be made of materials such as carbon composition, cermet, conductive plastic, or wire wound.

Types

There are several types of potentiometers, including:

• **Rotary Potentiometers**: These have a rotary knob or dial that adjusts the resistance.
• **Linear Potentiometers**: These have a slider that moves linearly to adjust the resistance.
• **Digital Potentiometers**: These are controlled electronically rather than manually.

Applications

Potentiometers are used in various applications, including:

• **Volume Controls**: Commonly used in audio equipment to adjust the volume.
• **Position Sensors**: Used in joysticks and other input devices to detect the position of the control.
• **Calibration**: Used in circuits to adjust the output to a desired level.

Operation

When a voltage is applied across the two end terminals of the potentiometer, the output voltage can be adjusted by moving the wiper along the resistive element. The output voltage is taken between the wiper and one of the end terminals.

Related Components

• Rheostat
• Variable capacitor
• Trimmer (electronics)

See Also

• Resistor
• Voltage divider
• Electrical impedance
• Ohm's law

Related Pages

• Resistor
• Rheostat
• Voltage divider
• Electrical impedance
• Ohm's law