The properties of this oxide layer compared with niobium oxide layer are given in the following table:Ĭharacteristics of the different oxide layers in tantalum and niobium electrolytic capacitors Anode-Īfter forming a dielectric oxide on the rough anode structures, a cathode is needed. This oxide layer serves as the dielectric in an electrolytic capacitor. Applying a positive voltage to the tantalum anode material in an electrolytic bath forms an oxide barrier layer with a thickness proportional to the applied voltage. Non-polar or bipolar tantalum capacitors are made by effectively connecting two polarized capacitors in series, with the anodes oriented in opposite directions.īasic information Basic principle īasic principle of the anodic oxidation, in which, by applying a voltage with a current source, an oxide layer is formed on a metallic anodeĮlectrolytic capacitors use a chemical feature of some special metals, historically called valve metals, which can form an insulating oxide layer. Reverse voltage can destroy the capacitor. Tantalum capacitors are inherently polarized components. Tantalum electrolytic capacitors are considerably more expensive than comparable aluminum electrolytic capacitors.

Because of its very thin and relatively high permittivity dielectric layer, the tantalum capacitor distinguishes itself from other conventional and electrolytic capacitors in having high capacitance per volume (high volumetric efficiency) and lower weight. It consists of a pellet of porous tantalum metal as an anode, covered by an insulating oxide layer that forms the dielectric, surrounded by liquid or solid electrolyte as a cathode. 10 μF 30 VDC-rated tantalum capacitors, solid electrolyte epoxy-dipped style.Ī tantalum electrolytic capacitor is an electrolytic capacitor, a passive component of electronic circuits.

Surface mount capacitor code chart pdf