4423results about "Inductance with magnetic core" patented technology

A feedthrough terminal assembly for an active implantable medical device (AIMD) includes a plurality of leadwires extending from electronic circuitry of the AIMD, and a lossy ferrite inductor through which the leadwires extend in non-conductive relation for increasing the impedance of the leadwires at selected RF frequencies and reducing magnetic flux core saturation of the lossy ferrite inductor through phase cancellation of signals carried by the leadwires. A process is also provided for filtering electromagnetic interference (EMI) in an implanted leadwire extending from an AIMD into body fluids or tissue, wherein the leadwire is subjected to occasional high-power electromagnetic fields such as those produced by medical diagnostic equipment including magnetic resonance imaging.

A low cost, low profile, small size and high performance inductive device for use in, e.g., electronic circuits. In one exemplary embodiment, the device includes a ferrite core comprising multiple inductors and optimized for electrical and magnetic performance. Improvements in performance are obtained by, inter alia, control of the properties of the gap region(s) as well as placement of the windings relative to the gap. The magnetic path properties of the inductors at the ends of the device are also optionally controllable so as to provide precise matching of inductances. Optionally, the device is also self-leaded, thereby simplifying its installation and mating to a parent device (e.g., PCB). Methods for manufacturing and utilizing the device are also disclosed.

A method and apparatus for hands free inductive charging of batteries for an electric vehicle is characterized by the use of a transformer having a primary coil connected with a charging station and a secondary coil connected with a vehicle. More particularly, the when the vehicle is parked adjacent to the charging station, the primary coil is displaced via a self alignment mechanism to position the primary coil adjacent to the secondary coil to maximize the inductive transfer of charging current to the secondary coil. The self alignment mechanism preferably utilizes feedback signals from the secondary coil to automatically displace the primary coil in three directions to position the primary coil for maximum efficiency of the transformer.

A feedthrough terminal assembly for an active implantable medical device (AIMD) includes a plurality of leadwires extending from electronic circuitry of the AIMD, and a lossy ferrite inductor through which the leadwires extend in non-conductive relation for increasing the impedance of the leadwires at selected RF frequencies and reducing magnetic flux core saturation of the lossy ferrite inductor through phase cancellation of signals carried by the leadwires. A process is also provided for filtering electromagnetic interference (EMI) in an implanted leadwire extending from an AIMD into body fluids or tissue, wherein the leadwire is subjected to occasional high-power electromagnetic fields such as those produced by medical diagnostic equipment including magnetic resonance imaging.

A TANK filter is provided for a lead wire of an active medical device (AMD). In a preferred form, the TANK filter is integrated into a TIP and / or RING electrode for an active implantable medical device. The TANK filter includes a capacitor in parallel with an inductor. The parallel capacitor and inductor are placed in series with the lead wire of the AMD, wherein values of capacitance and inductance are selected such that the TANK filter is resonant at a selected frequency to attenuate current flow through the lead wire along a range of selected frequencies. In a particularly preferred form, the TANK filter is manufactured using very low k materials of sufficient strength to handle forces applied thereto during installation and use.

There is disclosed a core structure with a very low profile, high power density and lower losses. Higher core surface area and improved core utilization in terms of flux density are other desirable feature in the disclosed design. The disclosed design also allowed for a larger core area where the DC fluxes are added, thereby reducing the air-gap requirements in the cores derived from low saturation density materials such as ferrites. The cellular nature of the design can also be effectively employed in vertically packaged power converters and modules.

A surface mount pulse transformer has a drum type core including a core and first and second flanges disposed on both ends of the core and installed on a substrate and a primary winding wire and a secondary winding wire wound around the core and provided with an intermediate tap, respectively, wherein first and second terminal electrodes being connected to each of both ends of the primary winding wire and a third terminal electrode for connecting being connected to the intermediate tap of the secondary winding wire are disposed on the surface of the first flange and a fourth terminal electrode being connected to the intermediate tap of the primary winding wire and fifth and sixth terminal electrodes being connected to each of both ends of the secondary winding wire are disposed on the surface of the second flange.

A surgical navigation system for navigating a region of a patient includes a non-invasive dynamic reference frame and / or fiducial marker, sensor tipped instruments, and isolator circuits. The dynamic reference frame may be repeatably placed on the patient in a precise location for guiding the instruments. The instruments may be precisely guided by positioning sensors near moveable portions of the instruments. Electrical sources may be electrically isolated from the patient.

There is disclosed a core structure with a very low profile, high power density and lower losses. The disclosed design allows for a larger core area where the DC fluxes are added, thereby reducing the air-gap requirements in the cores derived from low saturation density materials such as ferrites. The cellular nature of the design can be effectively employed in vertically packaged power converters and modules. Also disclosed is a DC-DC converter topology which preferably employs the disclosed core. N AC drive voltages drive N current doubler rectifiers (CDRs) in accordance with the symmetric modulation scheme; each CDR provides two rectified output currents to an output node. Each AC drive voltage has a switching period Ts. The drive voltages are phase-shifted by Ts / (2*N), such that the rectified output currents of the CDRs are interleaved, thereby reducing output voltage ripple.

A flux concentrator and method for manufacturing a flux concentrator is provided. The method can include combining powdered soft magnetic material, a binder, a solvent, a internal lubricant; mixing the materials to create a mixture, evaporating the solvent from the mixture, molding the mixture to form a flux concentrator, and curing the flux concentrator. The flux concentrator may be laminated and broken into multiple pieces, which makes the flux concentrator more flexible. Breaking the flux concentrator does not significantly affect the magnetic properties. Since the permeability of the binder is very similar to that of air, adding tiny air gaps between the fractions is not significantly different than adding more binder.

An integrated magnetic assembly that allows the primary and secondary windings of a transformer and a separate inductor winding to be integrated on a unitary magnetic structure is disclosed. The unitary magnetic structure includes first, second, and third legs that are physically connected and magnetically coupled. The primary and secondary windings of the transformer can be formed on the third leg of the unitary magnetic structure. Alternatively, the primary and secondary windings can be split between the first and second legs. Thus, the primary winding includes first and second primary windings disposed on the first and second legs and the secondary winding includes first and second secondary windings disposed on the first and second legs. The inductor winding may also be formed either on the third leg or it may split into first and second inductor windings and disposed on the first and second legs. In addition, one or more legs may include an energy storage component such as an air gap. This integration of the primary and secondary windings and the inductor winding on the unitary magnetic structure advantageously decouples the inductor function from the transformer function and allows the more optimal design of both the inductor and the transformer. The unitary magnetic structure may be coupled to a full bridge, a half bridge, or a push pull voltage input source to form a DC—DC converter.

A power converter includes a power train with a coupled inductor and a plurality of regulators, and method of forming and operating the same. In one embodiment, the power train includes a coupled inductor including a magnetic core with a common leg, a first leg and a second leg. The coupled inductor also includes a common winding formed around the common leg, and first and second windings. The first winding is formed around the first leg, and is electrically and magnetically coupled to the common winding. The second winding is formed around the second leg, and is electrically and magnetically coupled to the common winding. The power train also includes a first regulator including a first main switch coupled to the first winding and a second regulator including a second main switch coupled to the second winding.

There are provided an antenna module-use magnetic core member, an antenna module and a portable information terminal provided with the same, capable of improving a communication distance without increasing a module thickness. In an antenna module (1) in which a sheet-formed magnetic core member (4) is stacked on an antenna substrate (2) on which a looped antenna is formed, one having a performance index, expressed by μ′×Q, of 300 or higher when Q is a reciprocal of a loss factor (tan δ=μ″ / μ′) expressed by a real part μ′ and an imaginary part μ″ of a complex permeability at an applied frequency is used as the magnetic core member (4).

A method for producing a high density inductor includes the steps of forming a coil having a spiral shape, sealing the coil in the interior of a core member, and forming a terminal electrode for allowing electric conduction to said coil on the outside of said core member. In this method, the coil is formed by repeating a process of forming a wire layer by means of a thin film forming process and a process of forming an additional wire layer on top of the wire layer by means of the thin film forming process to pile up the wire layers. With this production method, it is possible to form a coil with a high aspect ratio. In addition, the inductor is designed in such a way that the core member envelopes only the coil. With that design, it is possible to make the inductor compact.

A storage magnetic element, which minimizes the power loss in the planar winding due to the fringe magnetic field associated with a discrete air gap, is presented. The invention describes a construction technique wherein the magnetic core is formed by an E section made of high permeability magnetic material and an I section made by a material capable to store energy due to its distributed gap structure. The I section of the magnetic core in one of the embodiments is covered by an electrically conductive shied to force the magnetic flux into the I section and to minimize the component of the fringe magnetic field perpendicular on the planar winding. In another embodiment of this invention the electrically conductive shield is replaced by a high magnetic permeability material to accomplished the same goal of reducing the magnetic field component perpendicular on the planar winding. In a prefer embodiment of this invention the I section of the magnetic core has a cavity which will accommodate the middle leg of the E section. This construction will force the fringe magnetic field at the edge of the gap to be parallel with the planar winding of the storage magnetic element. In another embodiment of this invention a flat I section is used with the addition of another high permeability magnetic material placed on the I section on top of the winding. This construction will force the fringe magnetic field around the edge of the gap to be parallel with the planar winding. The embodiments of this invention are aimed at reducing the fringe magnetic field perpendicular on the planar winding, lowering the eddy current induced by this field.

The invention is comprised of a coil group arranging a plurality of terminal-integrated type coils (1), (4) formed by bending a metal sheet in a preset development form and having a predetermined positional relationship, and a magnetic material (7) burying therein the coil group. For example, axes of the plurality of coils (1), (4) constituting the coil group, are arranged in parallel wherein the center point of at least one coil selected from the plurality of coils (1), (4) and the center point of a coil other than the selected coil are in an staggered arrangement. Due to this, an array type choke coil can be realized which is thin overall and operable with a large current in a high frequency band.

This invention discloses an inductor that includes a conducting wire composed of an alloy having temperature coefficients of resistance (TCR) approximately 0.0002 milliohm per Celsius degree or is lower. The inductive coil has a winding configuration provided for enclosure in a substantially rectangular box with a mid-plane extended along an elongated direction of the rectangular box wherein the conducting wire interesting at least twice near said mid-plane.

A low cost, low profile, small size and high performance inductive device for use in, e.g., electronic circuits. In one exemplary embodiment, the device includes a ferrite core comprising multiple inductors and optimized for electrical and magnetic performance. Improvements in performance are obtained by, inter alia, control of the properties of the gap region(s) as well as placement of the windings relative to the gap. The magnetic path properties of the inductors at the ends of the device are also optionally controllable so as to provide precise matching of inductances. Optionally, the device is also self-leaded, thereby simplifying its installation and mating to a parent device (e.g., PCB). Methods for manufacturing and utilizing the device are also disclosed.

The present invention provides a transformer formed from adjacent conducting layers of a multi-layer PCB and at least one additional conducting layer in contact with the PCB. The inventive transformer includes one or more winding turns of a first winding formed by connecting the multiple layers of the multi-layer PCB with conductive vias and one or more winding turns of a second winding formed by connecting one or more other layers of the multi-layer PCB. The additional conducting layer or layers is connected to respective selected one or more of said conducting layers of said PCB. In one embodiment, an additional conducting layer is soldered to a top conducting layer of the PCB, effectively increasing the cross-sectional area of the top winding layer. In another embodiment, an additional conducting layer is separated from a conducting PCB layer formed on the surface thereof by a layer of insulation, permitting the additional conducting layer to form a separate winding turn. The inventive transformer can be surface mounted to a PCB, and can be used in other electromagnetic devices. The windings thus constructed are capable of accepting larger currents with lower resulting temperature increases than windings formed only from PCBs, and are less expensive to manufacture than PCB-only windings.

A magnetic device includes a T-shaped magnetic core, a wire coil and a magnetic body. The T-shaped magnetic core includes a base and a pillar, and is made of an annealed soft magnetic metal material, a core loss PCL (mW / cm3) of the T-shaped magnetic core satisfying: 0.64×f0.95×Bm2.20≦PCL≦7.26×f1.41×Bm1.08, where f (kHz) represents a frequency of a magnetic field applied to the T-shaped magnetic core, and Bm (kGauss) represents the operating magnetic flux density of the magnetic field at the frequency. The magnetic body fully covers the pillar, any part of the base that is located above the bottom surface of the base, and any part of the wire coil that is located directly above the top surface of the base.

A surface mount coil comprises: a flanged spool, which includes a spool section and a flange section integrally connected with one end of the spool section; a base flange, which is shaped substantially rectangular and fixedly connected to the other end of the spool section; and an edgewise wound coil, which is made of a rectangular insulated wire, and which is structured such that starting and finishing ends of the rectangular insulated wire lead out in parallel with each other around the base flange in such a manner as to extend along and on one side surface, a bottom surface, and another side surface opposite to the one side surface, and are fixed at an edge of a top surface of the base flange.

A coil-type electronic component has a coil inside or on the surface of its base material and is characterized in that: the base material is constituted by a group of grains of a soft magnetic alloy containing iron, silicon and other element that oxidizes more easily than iron; the surface of each soft magnetic alloy grain has an oxide layer formed on its surface as a result of oxidization of the grain; this oxide layer contains the other element that oxidizes more easily than iron by a quantity larger than that in the soft magnetic alloy grain; and grains are bonded with one another via this oxide layer.