Showing papers on "Tantalum capacitor published in 1974"

Screen printed solid electrolytic capacitor

Abstract: A solid tantalum capacitor is made by screen printing on a tantalum substrate, a thick mixture of tantalum powder and a binder, sintering the printed layer, forming a dielectric oxide, and forming a counterelectrode. A large number of capacitors may be so made on a single substrate and thereafter individual or groups of capacitors are separated, and may have leads attached thereto. The planar geometries provide simple packaging on conventional DIP's and in hybrid integrated circuits.

Method for fabricating a thin film capacitor

Abstract: A process has been developed for fabricating a nonpolar low loss thin film capacitor utilizing tantalum oxide for high capacitance per unit area as a dielectric which is deposited in film form relative to a suitable substrate. A counter electrode is deposited on a substrate. A film of metal having a high recrystallization temperature is deposited on the counter electrode. This deposition forms the bottom electrode of the capacitor structure. The metal film has a quality thermal expansion resistance and a high reliability in thermal environments.

Method of assembling a tantelum capacitor

Abstract: A method of making a tantalum capacitor molds a plug in situ on one end of an anode and about a connector which projects through the molded plug for electrical connection with the anode. A spacer is molded in situ on the other end of the anode. During molding, the plug and spacer form a permanent bond with the anode to form a core unit comprising the plug, connector, anode, and spacer. Ribs extending along sides of the anode connect the plug to the spacer to improve the physical integrity of the core unit. The core unit is then inserted in a can which is filled with a fluid electrolyte and crimped about the plug to seal the can. The preferred practice of the method additionally bonds the plug to the can and connector to hermetically seal the capacitor. A capacitor made according to the preferred method then comprises the core unit hermetically sealed in the electrolyte filled can.

Method of forming a solid tantalum capacitor

Abstract: A method is disclosed for forming a solid tantalum capacitor wherein the cathode is manganese dioxide formed by pyrolysis. The first pyrolysis is performed at a temperature of between 225 DEG C and 300 DEG C while all subsequent pyrolysis treatments are at a temperature of between 175 DEG C and 225 DEG C with each such subsequent pyrolysis temperature being at least 25 DEG C less than the first pyrolysis temperature.

Method and system for determining the resistance of the dielectric in a capacitor

Abstract: A rapid and accurate indication of the resistance of the dielectric in a capacitor with respect to a minimum acceptable value is obtained by connecting the capacitor in a feedback circuit of a high gain amplifier between an output and an input thereof. Initially, the capacitor is rapidly charged through a variable resistance connected to the input of the amplifier, until the charge on the capacitor is equal to a set value, such as its rated voltage. The variable resistance then is abruptly increased to a predetermined value that will maintain the charge on an acceptable capacitor at the set charge value. The voltage output of the amplifier then is monitored to ascertain stability, further charging or discharging of the capacitor, to provide an indication as to whether the capacitor''s dielectric resistance is at, above or below the minimum acceptable value, respectively.

Capacitor having a plurality of anode risers for low impedance at high frequency

Abstract: The disclosure relates to an electrical component with low impedance over a range of high frequency input signals. The electrical component comprises a body including a metal anode with a plurality of anode risers contacting the anode, each of the anode risers extend from the anode a relatively short distance with a minimum of spacing therebetween. Anode and cathode levels extend from the body a relatively short distance in spaced substantially parallel relationship with each other. Preferably, the lengths of the anode and the cathode leads are a minimum as well as is the distance between each of the leads in order to further help reduce the impedance of the electrical component over a range of high frequency input signals. An example of an electrical component body is a solid tantalum capacitor comprising an anode of a dielectric oxide film-forming metal with a myriad of intercommunication voids, a dielectric oxide film of the metal contacting surfaces of the anode, and an electrolyte material contacting the dielectric oxide film.

Electrical component with low impedance at high frequency

Abstract: The disclosure relates to an electrical component with low impedance over a range of high frequency input signals. The electrical component comprises a dielectric film-forming metal anode with an anode lead projecting from the anode, electrolyte contacting the surfaces of the anode to form a body, and a cathode lead contacting the body and substantially parallel to the plane of the anode lead. Preferably, the length of the anode lead and the cathode lead are a minimum as well as is the distance between the anode lead and the cathode lead in order to help reduce the impedance of the electrical component over a range of high frequency input signals. Surfaces of the body are at an angle with respect to each other. The cathode lead includes an elongated strip of electrically conducting material projecting from the body and a surface of the strip is joined to one or more of the surfaces of the body at an angle with respect to each other. Preferably, the elongated strip of the cathode lead is joined to one of the surface of the body. An example of an electrical component body is a solid tantalum capacitor.

Potential measuring capacitor

Abstract: Potential measuring capacitors for high voltage power lines typically comprise a stack of individual capacitor elements connected in series and provided with a high voltage lead connected to the individual capacitor element at the top of the series, a ground lead connected to the individual capacitor element at the bottom of the series, and an intermediate lead connected to an intermediate point in the series. The intermediate lead divides the series into a first or upper capacitor C1 between the intermediate and high voltage leads and a second or lower capacitor C2 between the intermediate and ground leads. The stack is divided by a mechanical barrier that supports the upper capacitor so that there is no weight pressure from the upper capacitor on the lower capacitor. With this arrangement, the temperature coefficient of the first or upper capacitor C1 is substantially equal to the temperature coefficient of the second or lower capacitor C2, so that a more accurate voltage measurement over a wider range of temperatures is provided.

Solid electrolytic capacitor with planar cathode lead

Abstract: The invention refers to a solid electrolytic capacitor, the anode and cathode leads of which are in known manner formed from a metal strip while the electrolytic capacitor per se comprises a metallic anode body which has a relatively large plane surface above which a dielectric layer and a cathode layer are stacked in that order. The cathode lead is a part formed from the metal strip and shaped as a plate having a surface that is at least as large as the plane surface of the anode body and faces the cathode layer.

Fluorelastomer coatings in capacitors

Abstract: OF THE DISCLOSURE A new capacitor construction such as a tantalum capacitor which is capable of sustained operation at high temperatures and which possesses significantly improved solderability and electrical properties. In one particular aspect there is disclosed in a solid capacitor for providing electrical capacitance due to a dielectric component in the capacitor, the improved construction including an anode, a cathode, and at least one coating composition applied in the construction between the anode and the cathode, the coating composition being comprised of a fluoroelastomer for providing the coating with thermal stability to temperatures of about 400-700°F., and a conductive pigment for providing conductivity to the coating, wherein the conductive pigment is made substantially of a finely particulated material selected from at least one of the group consisting of noble metals, silver, copper, and alloys thereof.

Capacitor and electrolyte

Abstract: An aluminum electrolytic capacitor having dimethylammonium acid salts in the electrolyte solution.

Voltage multiplier arrangement with capacitor rolls surrounded by diodes

Abstract: A voltage multiplier includes a plurality of capacitors and diodes in an integral unit. The capacitors are combined in capacitor rolls surrounded by diodes on the outside of the diodes can be positioned between two capacitor rolls. AC and dc-voltageoperated capacitors can be combined in separate or the same rolls. The ac capacitors may be located inside within the roll and the dc capacitors on the outside of the same roll. The capacitor plates are made of aluminum foil with intermediate polystyrene and polyester layers. A common capacitor electrode plate may be used for adjacent capacitors.

Trends in the Design and Performance of Tantalum Capacitors

Abstract: This paper shows the type of development that has occurred over recent years in tantalum capacitors, with particular reference to the sintered tantalum powder – liquid electrolyte (wet Ta) system. In the ‘wet’ system, the various defects that arise, such as silver migration, scintillation and field crystallisation, are illustrated and the effect of improvement in initial particle shapes on final surface area is considered.

Stored charge in tantalum capacitors: Latent and manifest mavericks

Abstract: Relatively permanent space-charge fields can be established in Ta-Ta 2 O 5 -MnO 2 capacitor structures by any of the following. 1. Ionizing radiation with forward bias (tantalum electrode positive), 2. Reverse bias without radiation, 3. Forward bias without radiation. All of the capacitors store charge by the first two mechanisms. Only when a permanent space-charge polarization field can be established by condition 3 can the unit be called a “maverick”. The existence of a space-charge field is manifested when the capacitor is exposed to radiation at no bias or low forward bias. An anomalously large release is observed as the space charge is relaxed by the ionization-generated carriers. The polarization is relaxed by successive radiation pulses, and the normal zero-bias signal is finally obtained. The polarization behavior arises due to nonuniform trapping of charge in the oxide. In a normal capacitor, the polarization under irradiation occurs when the ionized electrons and holes are separated by the electric field in the oxide. Since the time and radiation history of the charge release in a maverick is similar to the charge release in a polarized normal capacitor, mavericks are apparently capacitors that can become polarized in the absence of radiation — for example, just due to an applied bias. This model has been simulated with the computer code PN, and the characteristics of the experimental data are reproduced. A maverick capacitor can be either latent or manifest, and a simple test for the zero-bias radiation response will not necessarily reveal a maverick unless a space-charge field has previously been established. These results are used to suggest tests to eliminate mavericks from the population.

Capacitor with glass metal conductive layer

Abstract: A glass-metal powder mixture, preferably including silver, is used in place of the usual epoxy resin-silver outer layer of a tantalum capacitor. This reduces temperature sensitivity during soldering and avoids penetration of silver into the graphite and manganese dioxide layers of the capacitor. Thinner layers of graphite and MnO 2 can be used and reduced carbonization provides improved conductivity. A small solder bead can also be used instead of dipping into a solder bath.