Technical Articles / Whitepapers

Next Generation of High Voltage, Low ESR SMD Tantalum Conductive Polymer Capacitors Exceeds 100V Milestone Written By: T. Zedníček | M.Bárta | J.Petržílek | M.Uher | I.Horáček | J. Tomáško | L. Djebara Abstract: Tantalum capacitors designed for high voltage applications (above 25V) have been used for many years in telecommunication, industrial, automotive or other high reliability applications. The conventional high voltage tantalum capacitor design is using a manganese dioxide cathode that provides good reliability, stability and robustness. Nevertheless there are certain limitations. First of all it is the operating voltage – even with optimized processes of dielectric formation, rated voltages of such parts are mostly limited to 50 or 63V. The other limitation is ESR. Very low ESR values

New Tantalum Technologies Tantalum Polymer and Niobium Oxide Capacitors Written By: T.Zedníček Abstract: Tantalum has been a favored capacitor technology in space-limited designs and high reliability applications for a long time. Recent years have seen the emergence of one or two equivalent technologies offering many of the advantages of tantalum, such as volumetric efficiency and reliability. Two new technologies recently introduced into their commercialization phase are niobium oxide capacitors and tantalum capacitors with conductive polymer cathodes. A circuit designer trying to choose between these solid electrolyte capacitor systems has a number of trade-offs and subtleties of operation to consider. This paper reviews the main features of the two technologies, the latest electronic application needs and discusses the feasibility of the

Investigation Into the Effects of Connecting Tantalum Capacitors in Series Written By: J.A. Gill Abstract: This paper demonstrates how high voltage capacitors can be made by connecting lower voltage rated parts in series. How to create large banks of capacitance by parallel and series combinations of capacitors without sacrificing reliability is also discussed.

Improved ESR on MnO2 Tantalum Capacitors at Wide Voltage Range Written By: I. Horacek | T. Zednicek | M. Komarek | J. Tomasko | S. Zednicek | W. A. Millman | J. Sikula | J. Hlavka Abstract: One common trend in switch-mode power supply, micro-processor, and digital circuit applications is to achieve reduced noise while operating at higher frequencies. In order to realize this, components with low Equivalent Series Resistance (ESR), high capacitance and high reliability are required. A new generation of Low ESR tantalum chip capacitors has been developed utilizing a low resistivity MnO2 electrolyte that enables very low component ESR. MnO2 technology provides excellent field performance, environmental stability and high electrical and thermal stress resistance in wide voltage

High CV Wet Tantalum DC Capacitors Written By: T.Zedníček | J.Petržílek Abstract: There are very many DC back up applications that require high energy storage capability. Rechargeable batteries and double layer carbon capacitors, (Electric Double Layer Capacitors or EDLC), have certain limitations in high temperature and harsh operational conditions. This paper will describe a novel application and design concept approach that will introduce High CV wet tantalum capacitors into this arena. Comparisons with supercapacitors and conventional wet tantalum capacitors will be given, with benchmarking of the capacitor technologies.

High CV Tantalum Capacitors Challenges and Limitations Written By: I.Horacek | T.Zednicek | S.Zednicek | T.Karnik | J.Petrzilek | P.Jacisko | P.Gregorova | I. Pinwill Abstract: The trend toward portable electronics is a major driving force in the need for miniaturisation of electronic components. Tantalum capacitors are becoming a product of first choice where high electrical and mechanical stability along with long service life and volumetric efficiency are demanded. The latest generation of ultra-high surface area tantalum powders in combination with an efficient constructional and encapsulation system provides a new solution for the next generation of component downsizing. This paper describes the main challenges and limitations in processes and materials that have been necessary to overcome for increased capacitance and

Hermetically Sealed 230°C MnO2 Tantalum Capacitors Written By: T. Zednicek | M. Biler | J. Petrzilek | I. Pinwill Abstract: Certain electronic applications, such as oil and gas exploration drilling, are continuously demanding ever higher operating temperatures. Recently operating temperature requirements have increased from 200°C to 230°C with an increased operating life from hours to one thousand hours and beyond. This need is linked with the continuous development of oil drilling heads and sensors and their use for deeper drilling or drilling in more difficult geological conditions. Capacitors with high capacitance value are a common part of the electronic boards used in these applications, but over 125°C/175°C, available capacitor choice is very limited. Tantalum SMD capacitor technology has proved its