A capacitor which is an energy-storage device is used to store energy between two conductors. These conductors are also called plates. An insulator is placed between these two plates. These plates are charged in order to store energy. One of the main function of a capacitor is to work as a filter. In this process blocks DC (Direct Current) and passes AC (Alternating Current).

There are various types of capacitors according to their designs and mechanisms. However, choosing a capacitor becomes quite interesting job, especially when we need to choose one according to our needs.

For Bypassing High Frequency to the Ground :

Ceramic Capacitor : It has relatively poorer capacitance. It is mostly used in a high frequency circuit. It looks like a disk in shape. It has dielectrics made of titanium acid barium. Basically, it is used to bypass high frequency to the ground.

Multilayer Ceramic Capacitor : Its function is same as a ceramic capacitor as it too is used to bypass signals of high frequency to the ground. It is a non-polarized capacitor ( So it comes in non polarized section too) . As per name, it contains a dielectric made of many layers of ceramic. It behaves well with extreme temperature and high frequencies.

For Large Value Capacitance :

Aluminum Capacitor : It consists of two electrodes. One being a negative and the other a positive one. Hence it has polarity. Largely, these electrodes are made of aluminum. The capacity of a electrolytic capacitor is measured on the scale of µF .The minimum capacity can be µF . While the maximum can lead to near 1000 µF. At some extent it shares its features with coils. Thus an electrolytic capacitor is not termed as something suitable for high-frequency circuits. Thus it is best used for low-frequency circuits where it works as a ripple filter.

Tantalum Capacitor : It is a type of electrolytic capacitor. The difference lies in the material used for the electrodes. As the name suggests, the electrodes for this type of capacitor is made of tantalum. However, in the matter of capacity it is better than any aluminum electrolyte capacitor. It is suitable for an analog circuit. Unlike an aluminum electrolytic capacitor, it is suits well for a high-frequency circuit. However, the making of a tantalum electrolytic capacitor needs more investment of money.

Super Capacitor : Termed by many as super capacitor only because its high level of capacitance. However, its actual name is electric double layer capacitor. It needs a lot of protective measures like a protection circuit to run it. Its high capacitance is prone to excessive inflow of electric waves which may be destructive to the circuit.

Non-polarized :

Mica Capacitors : This capacitor is one of the most expensive capacitors. However, it carries low capacitance. It is very safe for high voltage circuits, high frequency filters and resonance circuits. It, a non-polarized capacitor, comes with very high quality of insulation.

Polystyrene Film Capacitors : Basically, it is used as filter circuits. Like a multilayer ceramic capacitor, it too is a non-polarized capacitor. As the name says, polystyrene is used for the making of dielectric. Internally, it has a shape like a coil. Thus it can be found to be suitable for low-frequency circuits only.