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Tantalum electrolytic capacitors exploit the tendency of tantalum to form a protective oxide surface layer, using tantalum powder, pressed into a pellet shape, as one "plate" of the capacitor, the oxide as the dielectric, and an electrolytic solution or conductive solid as the other "plate". Because the dielectric layer can be very thin (thinner than the similar layer in, for instance, an aluminium electrolytic capacitor), a high capacitance can be achieved in a small volume. Because of the size and weight advantages, tantalum capacitors are attractive for portable telephones, personal computers, and automotive electronics.

Tantalum capacitors are a form of electrolytic capacitor. However, some forms of them are non-polar, containing two capacitors connected in series(negative to negative). The conductive polymer manufactured in our unique method is used for the cathode of Tantalum Capacitor, resulting in the reduction of ESR (equivalent series resistance) compared with the conventional manganese dioxide products.

Tantalum capacitors are under some conditions prone to self-destruction by thermal runaway. The capacitor typically consists of a sintered tantalum sponge acting as the anode, a manganese dioxide cathode, and a dielectric layer of tantalum pentoxide created on the tantalum sponge surface by anodizing. The tantalum oxide layer may have weak spots that undergo dielectric breakdown during a voltage spike. The tantalum then comes to direct contact with manganese dioxide and the leakage current causes a local heating; a chemical reaction then produces manganese(III) oxide and regenerates (self-heals) the tantalum oxide layer.

If the energy dissipated at the failure point is high enough, a self-sustaining exothermic reaction may occur, similar to the thermite reaction, with tantalum as fuel and manganese dioxide as oxidizer, destroying the capacitor and occasionally producing smoke and possibly flame.

The dielectric is then formed over all the tantalum particle surfaces by the electrochemical process of anodization. To achieve this, the “pellet” is submerged into a very weak solution of acid and voltage is applied. The total dielectric thickness is determined by the final voltage applied during the forming process. Initially the power supply is kept in a constant current mode until the correct voltage (i.e. dielectric thickness) has been reached, it then holds this voltage and the current decays to close to zero to provide a uniform thickness throughout the device and production lot. The chemical equations describing the dielectric formation process are as follows:

2 Ta → 2 Ta5+ + 10 e−
2 Ta5+ + 10 OH− → Ta2O5 + 5 H2O

The oxide forms on the surface of the tantalum but it also grows into the material. For each unit of oxide two thirds grows out and one third grows in. It is for this reason that there is a limit on the maximum voltage rating of tantalum oxide for each of the present technology powders.

Tantalum capacitors are a particularly useful form of capacitor. They offer a high capacity density, and provided they are operated within their ratings, they offer a high degree of reliability. Also they lend themselves to surface mount technology and in this guise tantalum capacitors are used in vast quantities each day.

Suntan provides Chip Tantalum Capacitor SMD—TS20, This type of capacitor is with 6 different sizes ( P case, A case, B Case, C case, D case, E Case ).

Tantalum SMD capacitors are widely used to provide levels of capacitance that are higher than those that can be achieved when using ceramic capacitors. The capacitor technology that is used within SMD tantalum capacitors is based on the solid tantalum capacitor technology. This is robust and enables very small capacitors to be made.

For many years tantalum capacitors were used in SMD applications because electrolytic capacitors were not able to survive the high temperatures of the soldering process. Now that electrolytic capacitor technology has been developed to withstand the soldering process, these capacitors are now also widely used. Despite this, the other advantages of tantalum capacitors are employed in many circuits, and they are still used in vast quantities.

Suntan’s Chip Tantalum Capacitor - SMD is solid electrolyte, high Volumetric efficiency, stable electric performances.

The following is Features:

• Molded case available in six case codes
• Compatible with all popular 'High Volume' automatic pick and equipment   
• Optical character recognition qualified

The most common form of leaded tantalum capacitors in use today are the "solid" tantalum capacitors. They offer particularly small package sizes and as a result they have been widely used in many areas of electronics.

Leaded tantalum capacitors (solid tantalum variety) are generally small and encapsulated in epoxy to prevent damage. The capacitor marking may be written directly onto the encapsulation as figures, although many used a color coding system.

Warning: - In view of the nature of these capacitors, great care should be taken not to stress these capacitors. The polarity should not be reversed, nor should they be exposed to over-voltage conditions - even spikes. If they are exposed to these conditions then they may fail, sometimes exploding.

The tantalum capacitor is a highly reliable type of solid capacitor or electrolytic capacitor. Surface mount tantalum capacitors are increasingly being used in circuit designs because of their volumetric efficiency, basic reliability and process compatibility.

Tantalum capacitors are manufactured from a powder of relatively pure tantalum metal. The typical particle size is between 2 and 10 μm. Surface area is expressed in capacitance (C) in microfarads (µF) times voltage (V) in volts (V) per gram of powder (CV/g) Note the very great difference in particle size between the powders.

Our Suntan Technology Company has many types of tantalum capacitors ,such as Dipped Tantalum Capacitor-TS19,Please see the detailed information on our website www.suntan.com.hk for your reference ,and welcome your enquiry about our all kinds of capacitors.

Tantalum Capacitors are electrolytic capacitors that is use a material called tantalum for the electrodes. Large values of capacitance similar to aluminum electrolytic capacitors can be obtained. Also, tantalum capacitors are superior to aluminum electrolytic capacitors in temperature and frequency characteristics. When tantalum powder is baked in order to solidify it, a crack forms inside. An electric charge can be stored on this crack.

These capacitors have polarity as well. Usually, the "+" symbol is used to show the positive component lead. Do not make a mistake with the polarity on these types.

Tantalum capacitors are a little bit more expensive than aluminum electrolytic capacitors. Capacitance can change with temperature as well as frequency, and these types are very stable. Therefore, tantalum capacitors are used for circuits which demand high stability in the capacitance values. Also, it is said to be common sense to use tantalum capacitors for analog signal systems, because the current-spike noise that occurs with aluminum electrolytic capacitors does not appear. Aluminum electrolytic capacitors are fine if you don't use them for circuits which need the high stability characteristics of tantalum capacitors.