The tantalum capacitor is an electrolytic capacitor, a passive component of electronic circuits. It consists of a porous tantalum metal pellet as an anode, covered by an insulating oxide layer that forms the dielectric, surrounded by liquid or solid electrolyte as a cathode. Due to its very thin and relatively high permittivity dielectric layer, the tantalum capacitor distinguishes itself from other conventional and electrolytic capacitors by having high capacitance per volume (high volumetric efficiency) and lower weight.
Tantalum is a conflict mineral. Tantalum electrolytic capacitors are considerably more expensive than comparable aluminum electrolytic capacitors.
Tantalum capacitors are polarized components. The reverse voltage can destroy the capacitor. Non-polar or bipolar tantalum capacitors like conventional bipolar electrolytic capacitors are made by effectively connecting two polarized capacitors in series, with the anodes oriented in opposite directions.
Tantalum capacitors are manufactured in a droplet format, axial cylindrical, in a plastic case with radial connection and chip type for surface mounting or smd. The SMD tantalums are the smallest of the three for obvious reasons.