Potentiometers are often used for parameter calibration, such as adjustable power supply, amplifier gain regulation, adjustable filter, LCD backlight regulation, noise-free adjustment of sound, etc. There are mechanical and digital types.
Mechanical advantages are: fixed after power on, high voltage and high current resistance, but poor temperature characteristics, greatly affected by mechanical vibration
Electronic: digital control can be changed, good stability, good temperature characteristics, the shortcomings are narrow voltage and current range, narrow bandwidth. The output range and current can be changed by series parallel connection of adjustable resistor. The bandwidth https://www.maximintegrat can be changed by corresponding methods.Ed.com/cn/app-notes/index.mvp/id/3081
The smaller the resistance of the digital potentiometer is. The more the steps, the larger the volume and the higher the cost.
Extension:
Digital controlled gain amplifier, tunable filter, adjustable power supply and so on.