capacitor

Tantalum capacitors are a subtype of electrolytic capacitors. They are made of tantalum metal which acts as an anode, covered by a layer of oxide which acts as the dielectric, surrounded by a conductive cathode. The use of tantalum allows for a very thin dielectric layer. This results in a higher capacitance value per volume, superior frequency characteristics compared to many other types of capacitors and excellent stability over time. 

A capacitor (originally known as a condenser) is a passive two-terminal electrical component used to store energy electrostatically in an electric field. It is a variable capacitor which has the facility to vary its capacitance value, but frequently once variation is sufficient, it is known as the trimmer capacitor. It is also called as simply trimmer or padder.  In some applications, the need for variation in the capacitance value is not frequent such a variable capacitor is trimmer capacitors. The trimmer is similar look like padder but padder has more plates and the size of padder is larger than trimmer. The trimmers are available in a number of shapes. The dielectric material is used for trimmers are ceramic, mica, or plastic. The capacitance value of the trimmer is ranged from 3 pF to 18 pF.