General Electric Company

Martin Marietta Corporation

Waseem A Roshen

Charles S Korman

Alexander J Yerman

Wolfgang Daum

Robert Louis Steigerwald

Bharat S Bagepalli

Richard J Saia

James William Bray

William Andrew Hennessy

Mario Ghezzo

John Andrew Mallick

Israel S Jacobs

Antonio A Mogro-Campero

A magnetic or electromagnetic circuit component includes an embedded magnetic material (e.g., ferromagnetic) in an HDI structure with alternating dielectric and metal or winding layers. In one embodiment, the ferromagnetic material is situated in a substrate well, or cavity, with or without an adhesive. Alternatively, the ferromagnetic material is co-fired with the ceramic substrate and then machined to achieve a required core shape. An electroplating process is employed to construct the metal layers, such process including differential plating for varying the thickness of metal layers and/or other portions of the circuit. Laser ablation or any other suitable technique is employed to make through-holes for insertion of the posts of a ferromagnetic core plate used to complete a magnetic circuit, if required. Advantageously, a magnetic or electromagnetic component may have a height of less than about 0.1 inch. Furthermore, such magnetic or electromagnetic circuit components allow for very low inductance interconnections between these components and other circuit elements. Moreover, in a power supply, for example, not only can the complete power supply be built using HDI technology, but power density is increased at relatively low cost and at a high level of reproducibility.

Method for making magnetic and electromagnetic circuit components having

A high frequency, high density, low profile magnetic circuit component includes a magnetic core having a first magnetic layer and a second magnetic layer with a conductive layer deposited therebetween, each magnetic layer being a multilayer structure comprised of alternating magnetic and insulating films. The magnetic films are anisotropic and are driven along their magnetic hard axis in order to reduce excess eddy current losses. To reduce fringing field eddy current losses, a distributed air gap is structured in the magnetic layers. The magnetic core has a distributed air gap formed therein in order to minimize eddy current losses in the conductive layer. The conductive layer has a conductive material patterned on a insulating substrate and is situated between the first and second magnetic layers such that the conductive material extends beyond the peripheries of the first and second magnetic layers, thereby maximizing the amount of magnetic material that is driven in the hard axis.

High frequency, high density, low profile, magnetic circuit components

A transformer having a very low, predetermined leakage inductance includes an elongate dielectric laminate having two surfaces. A primary winding having a pattern conformal to the configuration of the laminate is disposed on one surface and extends substantially the length of the laminate. The laminate has at least one secondary winding disposed on its other surface. The laminate is rolled with a dielectric layer about a cylinder, and the primary and secondary windings are patterned such that the primary and secondary windings comprise interleaved winding layers with the dielectric layer disposed between each of the winding layers. The rolled laminate, dielectric layer, and windings are contained within a cylindrical magnetic pot core. The result is a transformer having tightly interleaved primary and secondary windings and, therefore, a very low leakage inductance. In addition, the distance between adjacent primary and secondary turns is fixed by the thickness of the dielectric layer; hence, the leakage inductance is highly predictable.

Very low leakage inductance, single-laminate transformer

Magnetic and electromagnetic circuit components having embedded magnetic

A micromachined electromagnetic switch, including two soft magnets situated in fixed positions above and below a permanent magnet, toggles between two fixed positions by the application of current in an actuator coil for a brief period. The permanent magnet is attached to a micromachined hinge or spring which moves under the action of a net force, thereby opening or closing the switch. Current in the actuator coil changes the relative strength of the magnetic forces due to the soft magnets. In the absence of current in the actuator coil, the switch is kept in the open or closed position by the attractive magnetic force between the permanent magnet and either the upper or lower soft magnet, whereby the stronger force is exercised between the permanent magnet and the nearest soft magnet.

Micromachined electromagnetic switch with fixed on and off positions

A multi-pole magnetic component, such as an inductor, includes z-folded conductive film windings and a core having a plurality of pairs of spaced apart core posts extending between a base plate and a top plate of the core. The core includes an air gap that is distributed substantially evenly along the flux path. Magnetic flux flows through the core posts in a series manner so as to have an opposite flux direction in adjacent poles. Preferably, the air gap is determined such that the ratio of the distance between each adjacent core post and the distance between the base and top plates results in magnetic fields that are substantially tangential to the surface of the conductive film winding. Furthermore, the core posts are preferably shaped to have a larger cross sectional area at the base portion of the posts than at the top portion thereof. Alternatively, the core posts are attached to the bottom plate and are inserted into suitably shaped cut-out portions of the top plate. In either case, the air gap between each core post and the respective core plate is smaller around the center of the core post than at the outer edges thereof. As a result, flux is concentrated near the center of the core posts, thereby reducing fringing fields which, in turn, minimizes high-frequency winding losses.

High-frequency, low-profile inductor

A low-profile, conductive film transformer includes a conductive film primary winding and a multi-turn, conductive film secondary winding. The multi-turn secondary winding is configured on a continuous secondary conductive film which is disposed on at least one surface of a secondary dielectric membrane and has at least two portions arranged as mirror images of each other. Each of the portions has a plurality of sections; and each of the sections includes an even number of apertures, each of the apertures corresponding to a separate respective magnetic pole. There are at least two adjacent poles per section along at least one longitudinal pole axis. The conductive film is z-folded to form a stack of winding layers with a single turn per two adjacent layers about each magnetic pole, each layer comprising one section of the winding. Each single turn about each respective adjacent pole along each longitudinal axis is connected in series to form a total number of secondary winding turns corresponding to the number of sections in each portion of the conductive film winding. The multi-turn secondary winding is interleaved with a conductive film primary winding and disposed in a magnetic core. All of the secondary winding terminations are integral with the winding itself and are aligned, allowing for simple connections therebetween as well as to other circuit components.

Multi-turn z-foldable secondary winding for a low-profile, conductive

An inductor uses high temperature superconductors in order to obtain high Q for high frequency operation. The superconductors are applied as thin films to substrates. In some embodiments, superconductor thin films are applied to opposite sides of the same substrate. Superconductive thin films are applied outside the magnetic field establishing superconductive thin films in order to shield against leakage of the magnetic field beyond the inductor. The inductor is connected to a capacitor to realize a resonant circuit used in a power conversion system.

Thin film superconductor inductor with shield for high frequency

A high-frequency, low-profile transformer having at least one pair of magnetic poles includes a primary winding having a z-folded, continuous primary conductive film with a generally serpentine configuration disposed on a primary dielectric membrane and further includes a z-folded, continuous secondary winding constructed from a plurality of secondary conductive film portions disposed on a secondary dielectric membrane. Each of the secondary conductive film portions is configured to form a single continuous path enclosing each of the magnetic poles in such manner that each path encloses one pole of each pair of the magnetic poles of each adjacent layer of the secondary winding. Each path thus continues along a respective fold of the winding stack. The secondary winding layers are interleaved with the primary winding layers and electrically connected together. In one preferred embodiment, the transformer has two pairs of magnetic poles, and each path formed by each secondary conductive film has a shape characterized as two generally ovoid portions connected together at a relatively wide midportion. Low-resistance conductive bridges are used to electrically connect the secondary conductive film portions together along alternate folds of the winding stack.

Z-foldable secondary winding for a low-profile, multi-pole transformer

A folded conductive film winding transformer provides a plurality of poles and enables increased turns ratios or power handling capacity in structures which must meet severe height limitations.

Growing community of inventors

Clifton Park, NY, United States of America

Waseem A Roshen