A potentiometer is a variable resistor where the resistance is varied manually so as to control the electric current. It is also known as potmeter or pot. It acts as a voltage divider.
How does an electric potentiometer work?
An electronic potentiometer is a passive electronic component. It works by shifting the position of a slide across a uniform resistance. In this type of potentiometer, the entire voltage is applied across the total length of the resistor, and the voltage output is the drop in voltage between the sliding contact and fixed contact.
Electric potentiometers have various applications in real life like calibrating s system, tuning filters, adjusting offset voltage, controlling the brightness of the screen and controlling the volume of sound.
An electronic potentiometer can be used over the mechanical potentiometer where precision is required. Size, mechanical wear and tear, wiper contamination, resistance drift, humidity, sensitivity to vibration, etc. are some of the disadvantages of a mechanical potentiometer. Hence, to overcome these disadvantages it is advised to use an electric potentiometer.
Types of Potentiometer
There are mainly two types of a potentiometer. Let us discuss each type.
- 1. Rotary Potentiometer: These are the most commonly used potentiometer where the wiper moves in a circular path.
- 2. Linear Potentiometer: Here the wiper moves in a linear path. These are also known as slider, slide pot or fader.
Advantages of a digital potentiometer
Here are some of the advantages of digital potentiometer:
- a. Increased accuracy
- b. Higher reliability
- c. Small size
- d. Unaffected by environmental conditions like humidity, vibration, shocks, wiper contamination, etc.
- e. No moving part
- f. Negligible resistance drift
- g. Tolerance up to ±1%
- h. Negligible power dissipation
Stepper motors allow easy and accurate positioning. These are used in various pieces of equipment for speed control and accurate rotation using the pulse signal. These motors can generate very high torque which makes them ideal for quick response and acceleration.
A stepper motor driver is a circuit which can be used to control or run a stepper motor. The market is filled with a lot of drive circuits, but the stepper motor controller is mostly used. A stepper motor driver usually consists of three parts:
- a. driver
- b. A controller
- c. Connections to the motor
Nowadays the market is filled with drive circuits. Some circuits are very easy to interface with a motor. You can run the motor by connecting the stepper motor to it. These circuits have different ratings for voltage and current and it should be selected according to the need of the motor to be used.