Tantalum Capacitors Information

Tantalum capacitors are used in smaller electronic devices, including portable telephones, pagers, personal computers (PCs), and automotive electronics. They differ in terms of form factor, technology, and capacitance type. Leaded tantalum capacitors have leads for connections to circuits. Surface mount or chip tantalum capacitors do not. For both types of products, technology choices include single layer, multilayer, and wound. Single layer tantalum capacitors use a monolithic dielectric. Multilayer products are small in size and made of many layers. They provide good frequency characteristics as well as excellent temperature stability. Wound tantalum capacitors are built by winding foils, sometimes by hand. In terms of capacitance type, there are two choices: fixed and variable. Fixed tantalum capacitors have a nonadjustable capacitance value. Variable tantalum capacitors can be set with a potentiometer or other adjustment mechanism. 

Selecting tantalum capacitors requires an analysis of performance specifications such as capacitance range, capacitance tolerance, DC rated voltage range (WVDC), equivalent series resistance (ESR), leakage current, dissipation factor and operating temperature. Capacitance measures the ability to store energy, given as C = K A/D, where A is the area of the electrodes, D is their separation, and K is a function of the dielectric between the electrodes. Normally, capacitance tolerance is measured as a percentage of capacitance. DC rated voltage range (WVDC) is the maximum continuous DC voltage that may be continuously applied to a tantalum capacitor at any temperature between the lower category temperature and the rated temperature. Equivalent series resistance (ESR) represents the extent to which tantalum capacitors act like resistors when charging and discharging. Dissipation factor (DF) is the ratio between the resistive and the reactive part of the impedance submitted to a sinusoidal voltage of specified frequency.

There are three main packaging specifications for tantalum capacitors: lead or termination type, mounting style, and packing method. Choices for lead type include surface mount technology (SMT), axial, radial, flying, tab, screw, gull wing, and J-leads. Mounting styles include SMT as well as through-hole technology (THT), bolt mounts, bracket mounts, and pole mounts. There are three main packing methods for tantalum capacitors: tape reel, tray or rail, and shipping tube or stick magazine. Polarized, non-polarized, and self-healing products are also commonly available.

• Placing Additional Capacitors at Input and Output?
  It is recommended to use high grade Electrolytic capacitor with low E.S.R or Tantalum capacitors together with a small capacitance Multi-layer Ceramic Capacitor paralleled - which ca provide good filtering for ripple and noise. MOTIEN Technology co., LTD. Language 繁體中文 简体中文 English 日本語. E-mail...
• Refractory Metals
  be protected with an inert gas to prevent embrittlement. Principal applications for tantalum are in capacitor anodes, filaments, gettering devices, chemical-process equipment, and high-temperature aerospace engine components. Columbium is used in superconducting materials, thin-film substrates, electrical...
• Guidelines for Testing Electronic Components
  electrolytic and tantalum capacitor polarity. Detecting reverse polarity of electrolytic and tantalum capacitors usually requires visual inspection since the capacitance value will appear correct during a brief electrical test. Testing diodes, LED's. With the right tester you can check a diode...