Three Types of Capacitors

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Various Types of Caps by Arizona Capacitors

Capacitors fall into a category of electronics called passive electronic components and they are the second most common component in the average circuit, next to resistors. There are various types of capacitors available to the design engineer, depending upon what he needs.

There are three different types or families of capacitors that will be discussed in this Hub; wound film capacitors, tantalum & electrolytic capacitors, and ultra-capacitors. Only the first one of these is wound. All of the others are manufactured by laying down a film via sputtering or some other method. Whereas, the wound film capacitor is produced via winding a metal film onto a core, as the name implies.

The tantalum and electrolytic capacitors have their own niches, such as higher frequency applications. The wound film capacitor, on the other hand, has been the workhorse for the electronics industry for a number of years, this is because, in no small part, of its reliability. There are a number of different types of wound film capacitors. These are mostly categorized by the type of film they are wound upon.

There are many wound film capacitors. The polycarbonate capacitor is a typical example of a wound film capacitor. It is often used in the instrumentation, filtering, and switching power supplies fields. They are also preferred for many applications because of their precision and stability.

The tantalum capacitor is a typical electrolytic capacitor. It is one that is used extensively in audio applications. It is manufactured from a tantalum powder. The dielectric is thin making a high capacitance achievable with a relatively small size, but they can also be more expensive as well. The electrolytic capacitor is one that used an electrolyte as one of its plates. They are able to create the highest capacitance’s of any capacitors. The other type of electrolytic capacitor is aluminium.

Lastly, we have the ultra-capacitor or super-capacitor. It is an electromechanical capacitor that has a high density level. They are also know as electric double layered capacitors (EDLC) and they can have capacitance up to 5,000 farads. They do not have the dielectric found in most other capacitors, but have a double layer of separation giving them a rating for higher voltages than the other more common types of capacitors.