The capacitor is one of the passive components and places an essential role in electronic circuits, widely used circuit blocking, coupling, bypassing, filtering, etc.
According to the dielectric material of capacitors, it can be divided into ceramic capacitors, tantalum capacitors, aluminum electrolytic capacitors and film capacitors.
Ceramic capacitors - The use of ceramic capacitors in circuits is the most widespread of all classifications. Its common uses are coupling, decoupling, smoothing and filtering.
Ceramic Capacitors
When a ceramic capacitor is used for the coupling function, it acts as a connection between two circuits, allowing the AC signal to pass and transfer to the next stage circuit. The working conditions of active components such as transistors and ICs on the circuit are different. Therefore, it is necessary to set the optimal working conditions for each circuit and then separate the required AC signal. Coupling capacitors are generally connected to the input terminals of amplifiers or op amps with ceramic capacitors.
There are capacitance and inductance components in the power line on the circuit. Due to its sound, once the voltage of the power line fluctuates greatly, the work of the circuit will become extremely unstable. At this time, the use of decoupling capacitors can lead the interference flowing from the power supply to the ground part, and continue to provide a stable current to the sharp changes in the load current of components such as ICs. Even in extreme cases where the interference generated overlaps, the interference can be directed to the ground section through the decoupling capacitor.
The smoothing capacitor is used to suppress the pulse generated on the power supply circuit after rectification, smooth the signal, store electricity at high voltage, and discharge it at low voltage, making it closer to DC.
The filter capacitor refers to an energy storage device installed at both ends of the rectifier circuit to reduce the AC ripple coefficient and improve the efficiency and smooth the DC output. By combining capacitors, resistors, and inductors, filters that pass only certain frequencies can be made. It is mainly divided into a low bypass filter that extracts only low frequency components and a high bypass filter that extracts only high frequency components.
Film capacitors - The capacitors made of metal foils as electrodes and plastic films as dielectrics through a winding or lamination process.
Because of its excellent frequency characteristics, particularly high insulation resistance, and non-polarity, it is often used in analog circuits. In addition, film capacitors have excellent performance in signal cross-connection, and the dielectric loss is small, which can meet people's pursuit of high sound quality when used in audio equipment.
Like ordinary capacitors, film capacitors also store electrical energy by storing charges on electrodes, and are usually used together with inductors to form LC oscillation circuits.
Film Capacitors
Tantalum capacitors - A type of electrolytic capacitors. They use metal tantalum as a medium, have almost no inductance, and are small in size. Since there is no electrolyte inside, it is very suitable for working at high temperature, and the temperature stability of its capacitance value is relatively good. Tantalum electrolytic capacitors have the properties of storing electricity, charging and discharging, etc. They are mainly used in filtering, energy storage and conversion, mark bypass, coupling and decoupling, and time constant components.
Tantalum capacitors
Aluminum electrolytic capacitors - Made of an aluminum cylinder as the negative electrode, which is filled with liquid electrolyte and inserted into a bent aluminum strip as the positive electrode. Compared with other capacitors, the same size, higher CV value and cheaper price.
Aluminum electrolytic capacitors
Capacitors are used for a variety of purposes and perform different functions in different circuits. Choosing the right capacitor is very important to the smooth progress of the project. While another key to success is to select a reliable distributor who can continually supply and offer stable prices and lead time. Hard Find Electronics LTD. is an electronic components distributor. Chip Capacitors is one of our strong product lines so that the stable price and continual supply are available.