Potentiometers
A potentiometer is a variable resistor used to adjust voltage levels in a circuit. It is commonly used for volume control, brightness control, and tuning applications.
What is a Potentiometer?
A potentiometer (often called pot) is a three-terminal device that allows you to vary resistance manually.
- Two terminals → fixed ends of resistive track
- One terminal → movable wiper
How It Works
When you rotate the knob:
- The wiper moves along the resistive track
- Voltage at the output changes
- Acts as a voltage divider
Voltage Divider Principle
::contentReference[oaicite:0]{index=0}The output voltage depends on the position of the wiper and resistance ratio.
Main Types of Potentiometers
- Rotary potentiometer
- Linear (slider) potentiometer
- Trimmer potentiometer
- Digital potentiometer
Common Values
- 1kΩ, 5kΩ, 10kΩ, 50kΩ, 100kΩ
- Linear (B type)
- Logarithmic (A type) – used for audio
Applications
- Volume control (audio amplifiers)
- Light dimmer circuits
- Signal adjustment
- Calibration circuits
Advantages
- Simple and low cost
- Easy to use
- Provides continuous control
Disadvantages
- Mechanical wear over time
- Limited precision
- Noise in audio circuits (cheap types)
Important Notes
- Acts as a voltage divider or variable resistor
- Choose correct resistance value
- Use logarithmic pots for audio volume