12/08/2014
Capacitors are quite a remarkable invention in the field of electronics. A capacitor/condenser is a passive two-terminal electrical component that can store energy electrostatically in an electric field. While different shapes and forms of capacitors have been developed with time, the essential configuration of each of them is more or less the same: all of these consist of at least two electrical conductors (plates) that are separated by a dielectric.
1.Film Capacitor
Film capacitors, plastic film capacitors, film dielectric capacitors, or polymer film capacitors, generically called “film caps” as well as power film capacitors, are electrical capacitors with an insulating plastic film as the dielectric, sometimes combined with paper as carrier of the electrodes. The dielectric films, depending on the desired dielectric strength, are drawn in a special process to an extremely thin thickness, and are then provided with electrodes. The electrodes of film capacitors may be metallised aluminum or zinc applied directly to the surface of the plastic film, or a separate metallic foil overlying the film. Two of these conductive layers are wound into a cylinder shaped winding, usually flattened to reduce mounting space requirements on a printed circuit board, or layered as multiple single layers stacked together, to form a capacitor body. Come in an assortment of shapes and case styles like: wrap & fill (oval & round), epoxy case (rectangular & round) and metal hermetically sealed (rectangular & round). All of these come in axial and radial leads.
Wrap & Fill (Oval & Round): capacitor wrapped in a tight plastic tape with its ends sealed with epoxy.
Epoxy Case (Rectangular & Round): capacitor encased in a moulded plastic shell filled with epoxy.
Metal Hermetically Sealed (Rectangular & Round): capacitor encased in a metal tube/can sealed with epoxy.
2.Ceramic Capacitor
A ceramic capacitor is a fixed value capacitor in which ceramic material acts as the dielectric. It is constructed of two or more alternating layers of ceramic and a metal layer acting as the electrodes. The composition of the ceramic material defines the electrical behavior and therefore applications.
3.Electrolytic Capacitor
An electrolytic capacitor is a capacitor that uses an electrolyte (an ionic conducting liquid) as one of its plates to achieve a larger capacitance per unit volume than other types. The large capacitance of electrolytic capacitors makes them particularly suitable for passing or bypassing low-frequency signals and storing large amounts of energy. They are widely used in power supplies,and interconnecting stages of amplifiers at audio frequencies. Come in two forms: Aluminium Electrolytic Capacitors and Tantalum Electrolytic Capacitors.
Aluminium Electrolytic Capacitors: compact but lossy, these are available in the range of
