What are the 4 types of variable resistor?

 Potentiometers and rheostats are other names for variable resistors, which are electronic parts whose resistance may be electronically or manually changed. There are various kinds of variable resistors; four typical varieties are as follows:

1、Rheostats: These are variable resistors with two terminals used to adjust current in a circuit. They typically consist of a resistive element (such as a coil of wire) and a movable wiper that makes contact with the resistive element. By moving the wiper, the effective length of the resistive element through which the current flows can be changed, thus altering the resistance.

2、Potentiometers: Potentiometers are also variable resistors with three terminals. They consist of a resistive element with a movable wiper. The wiper can be adjusted to make contact with different points along the resistive element. By connecting the input voltage across the outer terminals and measuring the voltage at the wiper terminal, potentiometers can be used to create variable voltage dividers or adjust voltage levels in a circuit.

3、Trimmers: Trimmers, also known as trimmer potentiometers or preset resistors, are variable resistors designed for adjustment during manufacturing or calibration processes. They are typically small, compact, and enclosed in a package that can be adjusted with a screwdriver or a specialized tool. Trimmers are often used for fine-tuning circuit parameters or setting initial values in electronic devices.

4、Digital Potentiometers: Digital potentiometers are electronic components that mimic the functionality of traditional potentiometers but use digital control signals instead of mechanical adjustments. They typically consist of a series of resistive elements and switches controlled by digital signals. Digital potentiometers offer advantages such as precise control, programmability, and the ability to interface with microcontrollers or digital circuits.

With the help of these four different kinds of variable resistors, electronic circuits can be tuned for a variety of purposes, such as circuit trimming, sensor calibration, volume controls, and tuning circuits.