The potentiometer can adjust the voltage division ratio and change the potential, and can be used as a three-terminal component or a two-terminal component. The latter can be regarded as a variable resistor, because its function in the circuit is to obtain an output voltage that has a certain relationship with the input voltage (applied voltage), so it is called a potentiometer. So what are the potentiometers commonly used in daily life? Let's take a look:
- Wirewound potentiometer
It has the advantages of high precision, good stability, small temperature coefficient, reliable contact, etc., and is resistant to high temperatures and strong power load capacity. The disadvantage is that the resistance range is not wide enough, the high frequency performance is poor, the resolution is not high, and the high resistance wirewound potentiometer is easy to break, larger in size, and higher in price. This kind of potentiometer is widely used in electronic instruments and meters. The resistor body of the wire-wound potentiometer is composed of a resistance wire wound on an insulator. There are many types of resistance wires. The material of the resistance wire is selected according to the structure of the potentiometer, the space of the resistance wire, the resistance value and the temperature coefficient. The thinner the resistance wire, the greater the resistance value and resolution in a given space. But the resistance wire is too thin, it is easy to disconnect during use, which affects the life of the sensor.
- Digital potentiometer
Potentiometer made with integrated circuit technology; integrate a string of resistors into a chip, and use MOS tube control resistor series network to connect to the common end; control accuracy is determined by the number of bits controlled, generally 8 bits, 10 bits, and 12 It can be used in analog circuits for impedance matching and amplification control of amplifying loops; it avoids troublesome jitter adjustment operations; it provides a convenient way for automatic gain, voltage change, impedance matching, etc. of the equipment.
- Metal glass glaze potentiometer
It not only has the advantages of organic solid core potentiometers, but also has a small resistance temperature coefficient (similar to wirewound potentiometers), but the dynamic contact resistance is large, and the equivalent noise resistance is large, so it is mostly used for semi-fixed resistance adjustment. This type of potentiometer has developed rapidly, and its ability to withstand temperature, humidity, and load impact has been improved, and it can work reliably under harsher environmental conditions.
- Synthetic carbon film potentiometer
It has the characteristics of wide resistance range, better resolution, simple process and low price, but it has high dynamic noise and poor moisture resistance. This type of potentiometer should be used as a functional potentiometer, which is widely used in consumer electronic products. The use of printing technology can automate the production of carbon membranes.
- Organic solid core potentiometer
The resistance value range is wide, the resolution is high, the heat resistance is good, the overload ability is strong, the abrasion resistance is good, the reliability is high, but the heat resistance and dynamic noise are poor. This type of potentiometer is generally made into a small semi-fixed form, which is used for micro-calling in the circuit.
- Conductive plastic potentiometer
It has wide resistance range, high linear accuracy, strong resolution, and particularly long wear life. Although its temperature coefficient and contact resistance are relatively large, it can still be used in analog and servo systems in automatic control instruments.
Summarized by Easybom. https://www.easybom.com/