How Do Capacitors Work?

Capacitors can be considered a staple of many electronic devices, serving a crucial role in overall functionality despite being such a small and simple item. Put simply, capacitors are electrical components capable of storing electrical energy within an electric field, acting as a passive component situated between two terminals. With this ability, known as “capacitance,” capacitors may perform a number of operations to benefit a diverse set of electrical applications. In this blog, we will provide a brief overview of capacitors, allowing you to have a better grasp on their use and design.

In order to effectively carry out operations, the typical capacitor assembly will feature at least two conductors, those of which may be metallic plates or surfaces. Separating the conductors is a dielectric material made of mica, plastic fill, paper, air, or other such substances, and it allows for capacitance to be increased as a result of its non-conductive properties.

As stated before, capacitors are able to store electrical energy, and they resist energy dissipation which sets them apart from similar passive components like resistors. However, energy will dissipate when in use. In order for a capacitor to begin storing energy, a voltage will first need to be applied to the terminals of the device. This will result in the dielectric being surrounded by an electric field, causing a net negative charge to collect on one plate of the capacitor, while the net positive charge collects on the other. Even though the capacitor’s source circuit will face a charge flow, no current flow will be received by the dielectric.

Capacitors can be procured in a number of types, the major differences between each being their design. Ceramic capacitors are a very common option, and they consist of alternating layers of metal and ceramic, where the ceramic substance serves as the dielectric. To adjust operational characteristics, the exact makeup of materials may be adjusted.

Film capacitors are also a widely recognizable type, and these are non-polarized options where insulating plastic film acts as the dielectric. As compared to other options, film capacitors feature very short current paths as a result of having direct contact with electrodes. For the electrodes, aluminum or zinc is common.

The final popular capacitor option is the electrolytic type, and these feature a metallic anode and an oxidized layer that covers the device. The layer itself acts as the dielectric, and aluminum, tantalum, and niobium subtypes are all common. With the anode being highly roughed, the surface area of the device is increased. Additionally, the construction of electrolytic capacitors allows them to have a high capacitance per unit volume when comparing other options.

With a better understanding of capacitors and the various options that are available, you may be better suited to find an option that fits your particular needs. Whether you are making a first time purchase or are simply looking to replace aging or defective components, it is important that you choose a reputable source for your procurement needs to guarantee top-quality products. Luckily for you, Limitless Purchasing is here to supply you with high-caliber products fit for your needs while ensuring competitive pricing and rapid lead times.

On our website, we offer customers access to over 2 billion new, used, obsolete, and hard-to-find items, all of which trace back to top manufacturers that we trust. If you find any items of interest while exploring our database, be sure to request quotes for your comparisons through the submission of our provided RFQ forms. Once we receive and review a completed submission, a member of our staff will reach out to you in 15 minutes or less to present a solution that has been tailored to your unique needs and restrictions. 


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