capacitor tantalum

7/23/2019 Capacitor Tantalum

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Brief Introduction To Tantalum Electrolytic Capacitors

Solid tantalum electrolytic capacitors first developed successfully at Bell Laboratory, USA. in

l956,feature excellent performances, higher capacitance in small size compared with other types of

capacitors. Tantalum capacitor has various forms of encapsu1ate, among them, miniature tantalum

chip capacitors are especially suitable for surface mounting applications to meet the demands of

development of current electronic automation technology and miniaturization. Although lack oftantalum raw materials and tantalum capacitors being more expensive, tantalum capacitors have still

grown with big strides and have been widely used for more and more applications because of using a

large quantity of high capacitance tantalum powder (30KUF.V/g-l00KUF.V/g) and improving

manufacture technology of capacitors continuously. Tantalum capacitors are widely used not only for

military applications, telecommunication, aerospace, etc., but also for industrial controls, digital

audio/video equipment, instruments and meters.

Tantalum electrolytic capacitors now available have mainly three categories of the solid sintered, foil

winded and wet sintered type. Among them, the sintered solid accounts for over 95％

of the current

total production, dominated by non－

hermetical epoxy-encapsulated tantalum capacitor. Along with

the development of SMT technology, miniaturization is in the ascendant and the ratio of chip type toall types of capacitors is growing, tantalum chip capacitors are playing a dominant role in the

markets．

Solid tantalum capacitors have advantages of excellent electrical performance, wide working

temperature range, good volume efficiency and various forms of encapsulation, uniquely

characterized in：

●Thin tantalum oxide(Ta2O5) film forms over all the tantalum surfaces, serving as working dielectric

of tantalum capacitors．

●The dielectric film can not exist alone, integrated with counter electrode of tantalum capacitor, thus

the capacitance of volume per unit or specific capacitance is larger, suitable for miniaturization．

●

During the operation, tantalum electrolytic capacitors feature self-healing and blocking defects of

the tantalum oxide film, strengthening dielectric at any time, recovering the capability of insulation

and preventing from continuous accumulative breakdown, The unique performance of self －

healing assures its long life and high reliability．

●Tantalum electrolytic capacitors have higher electric field strength compared with any other type

of capacitor．

●

Tantalum electrolytic capacitors have higher capacitance, used for applications in power filtering,

bypassing, coupling, etc, meeting no competition from other capacitors．

●

Tantalum electrolytic capacitors have unilateral conductivity or polarity. When using, tantalum

capacitor is connected accordingly. Wrong connection result in increasing DC leakage, thereby

heating up In the anode In a short time, breaking down of the dielectric, at the meantime, the

capacitor became defected part．

●There is an upper limit for working voltage, but it is negligible when using the capacitors togetherwith transistors or integrated electric circuit or power supply．



Electrolytic capacitor is usually regarded as a kind of electronic component with excellent

performance and long working life, its failure rate under normal condition can be up to VⅡ Grade,

but still conform to common failure pattern of electronic components, that is bathtub－shape failure

curve. Failure parts at earlier stage can be eliminated during aging, thus only accidental failure is

possible. The failure may result from both defects of raw materials and problems on process control

or improper use or overload of the capacitors. Speaking, there are three failure modes: electric

current, electric voltage and heating-up modes．

Tantalum electrolytic capacitors also feature storing electric charge, charging and discharging, etc,

mainly used for filtering, storing electric energy and conversion, signal bypassing, coupling and

decoupling, also used as a time-constant component, etc. The user should pay attention to its

performances and use them properly, thus the functions can be brought Into full use, when using, the

user should give consideration to such factors as working environment, heating temperature and

adopt such measures as sing by voltage derating, moreover improper use may have influenceon

working life of the capacitors．

Except for sintered solid tantalum chip capacitor as dominant product, UB. also provide sintered,

epoxy-coated solid tantalum electrolytic capacitor with radial lead, metal－

cased solid tantalumelectrolytic capacitor, metal cased wet tantalum electrolytic capacitor and sintered, conformal

－

coated solid tantalum chip capacitor. They have various constructions, encapsulate forms and shapes.

● Sintered Solid Electrolyte Tantalum

●Sintered Cylindrical Epoxy Coated Solid Electrolyte Tantalum Capacitor



●Sintered Metal Cased Solid Electrolyte Tantalum Capacitor

●Sintered Metal Cased Solid Electrolyte Tantalum Capacitor

●Sintered Conformal Coated Solid Electrolyte Tantalum Chip Capacitor

capacitor tantalum

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