The advantages and disadvantages of several commonly used potentiometers

Potentiometer is a common electronic component. Today, we will introduce several potentiometers commonly used in the market and the advantages and disadvantages of these potentiometers.

1. Synthetic carbon film potentiometer

The resistor body of the synthetic carbon film potentiometer is made by mixing carbon film, graphite, quartz powder and organic powder mixture into a suspension and coating it on glass glaze fiberboard or adhesive paper. The production process is simple, and it is currently the most widely used potentiometer. The advantages of synthetic carbon film potentiometers are: wide resistance range, high resolution, can be made into various types of potentiometers, long life, low price, and many models. The disadvantages are: the power is not too high, high temperature resistance, poor humidity resistance, and low resistance potentiometers are not easy to make.

2. Organic solid core potentiometer

The organic solid core potentiometer is a new type of potentiometer, which uses the method of heating and plastic pressing to press the organic resistance powder into the groove of the insulator. Compared with carbon film potentiometers, organic solid core potentiometers have the advantages of good heat resistance, high power, high reliability and good wear resistance. However, the temperature coefficient is large, the dynamic noise is large, the moisture resistance is poor, the manufacturing process is complicated, and the resistance accuracy is poor. It is used to adjust voltage and current in miniaturized, highly reliable, high wear resistance electronic equipment and AC and DC circuits.

Three, metal film potentiometer

The metal film potentiometer is made by depositing several materials such as metal composite film, metal oxide film, metal alloy film and button oxide film on the ceramic substrate through vacuum technology. Advantages: good heat resistance, high resolution, small distributed inductance and distributed capacitors, and low noise electromotive force. Disadvantages: poor wear resistance, small resistance range (10 Ω -100K Ω).

Four, winding potentiometer

The wire-wound potentiometer is made by using constantan wire or nickel-chromium alloy wire as a resistor and winding it on an insulating frame. Advantages of wire-wound potentiometers: small contact resistance, high precision, and small temperature coefficient. Disadvantages: poor resolution, low resistance, poor high-frequency characteristics. It is mainly used as a voltage divider, transformer, zero adjustment and adjustment of operating points in the instrument, etc.

Five, digital potentiometer

The digital potentiometer eliminates the moving parts and is a semiconductor integrated circuit. The advantages are: high adjustment accuracy, no noise, extremely long working life, no mechanical wear, data read/write, configuration register and data register, multi-level storage function, easy software control, small size, easy assembly . It is suitable for home theater systems, audio surround control, audio amplifiers and cable television equipment.