Abstract: A coil component includes a drum-shaped core including a core portion that extends in a length direction of the coil component and a first flange portion provided on a first end portion of the core portion, and first and second terminal electrodes provided on the first flange portion. The first and second terminal electrodes each include a base electrode formed on a surface of the first flange portion and a plating layer that covers the base electrode. The base electrode includes a bottom-surface base electrode portion on a bottom surface, an end-surface base electrode portion on an end surface, and a side-surface base electrode portion on a first side surface. The end-surface base electrode portion has a height greater than that of the first crotch portion. The side-surface base electrode portion has a height less than that of the first crotch portion.

Abstract: A coil component includes: a body; a coil unit disposed in the body; a support substrate unit in contact with the coil unit to support the coil unit, and including first and second support substrates spaced apart from and oppose each other; and first and second external electrodes disposed on a first surface of the body and spaced apart from each other, and respectively connected to the coil unit.

Abstract: An inductor comprises a core and a coil. The coil has a first terminal, a second terminal, a first portion, a second portion, a third portion, a first coupling portion, a second coupling portion, a first extending portion and a second extending portion. Each of the first portion and the second portion is positioned apart from a first edge of the core. Each of the first portion and the second portion is parallel to the first edge. Each of the first portion and the second portion is positioned apart from the third portion in a first horizontal direction. The third portion is positioned apart from a second edge of the core. The third portion is parallel to the second edge. The first extending portion couples the first portion and the third portion with each other. The second extending portion couples the second portion and the third portion with each other.

Abstract: A common-mode choke coil includes a multilayer body, a first coil, a second coil, a first terminal electrode, a second terminal electrode, a third terminal electrode, and a fourth terminal electrode. The multilayer body includes plural non-conductor layers. The first and second coils are incorporated in the multilayer body. The first and second terminal electrodes are connected to the first coil. The third and fourth terminal electrodes are connected to the second coil. The first coil has a path length L1, the second coil has a path length L2, and the sum of the path length L1 and the path length L2 is less than or equal to 3.4 mm. The respective lower-face electrode portions of the terminal electrodes each have an area of less than or equal to 0.034 ?m2.

Abstract: A coil component includes an insulating base body and a coil conductor arranged in the base body and having a winding portion extending around a coil axis. The insulating base body includes a magnetic body portion made of a magnetic material and a magnetic gap portion made of a low-permeability material having a lower relative permeability than the magnetic material. The magnetic gap portion is shaped like a ring when seen in a direction along the coil axis and arranged within the winding portion. The magnetic body portion includes a first region positioned within the winding portion, a second region positioned opposite the first region with respect to the magnetic gap portion in the direction along the coil axis, and a third region arranged within a through hole defined by an inner peripheral surface of the magnetic gap portion, where the third region connects together the first and second regions.

Abstract: A multilayer electronic component includes a body including a dielectric layer and a first internal electrode and a second internal electrode and having first to sixth surfaces, a first external electrode including a first connection portion on the third surface, a first band portion on the first surface, and a third band portion on the second surface, a second external electrode including a second connection portion on the fourth surface, a second band portion on the first surface, and a fourth band portion on the second surface, an insulating layer disposed on the second surface and extending onto the first and second connection portions, a first plating layer disposed on the first band portion, and a second plating layer disposed on the second band portion. The insulating layer includes glass, and a region disposed on the second surface in the insulating layer has a convex shape in the first direction.

Abstract: A coil component includes a body, a coil portion disposed in the body, and first and second external electrodes disposed on the body to be spaced apart from each other, wherein A/C?2.4 and B/C?1.6 are satisfied, where a length, a width, and a thickness of the coil component are defined as ‘A’, ‘B’, and ‘C’, respectively, and a ratio of a thickness to a width of at least one turn of the coil portion is 1 or less, based on a cross-section of the coil component.

Abstract: Disclosed herein is a coil component that includes first, second, third, and fourth terminal electrodes; a first planar spiral coil formed on a substrate, the first planar spiral coil having an outer peripheral end connected to the first terminal electrode; a second planar spiral coil stacked on the first planar spiral coil through a first insulating layer, the second planar spiral coil having an outer peripheral end connected to the second terminal electrode; and first and second lead-out patterns stacked on the second planar spiral coil through a second insulating layer. The first lead-out pattern connects the third terminal electrode and an inner peripheral end of the first planar spiral coil. The second lead-out pattern connects the fourth terminal electrode and an inner peripheral end of the second planar spiral coil. The second insulating layer is thicker than the first insulating layer.

Abstract: An apparatus comprising two inductors; wherein the two inductors are layered on top of each other in different layers of metal of a circuit; wherein each inductor of the inductor has a set of turns; wherein the current path of the two inductors is in the same direction.

Abstract: The present disclosure provides a transformer module and a power module, wherein the transformer module comprises: a magnetic core, where a first insulating layer and a second wiring layer are sequentially disposed on the magnetic core from inside to outside; a first metal winding, wound around the magnetic core and comprising a first winding segment formed in the first wiring layer and a second winding segment formed in the second wiring layer; and a second metal winding, wound around the magnetic core and comprising a third winding segment formed in the first wiring layer and a fourth winding segment formed in the second wiring; where at least part of the first metal winding and the second metal winding are wound around the magnetic core in a foil structure.

Abstract: A multilayer-type on-chip inductor with a conductive structure includes an insulating redistribution layer disposed on an inter-metal dielectric layer, a first spiral trace layer disposed in the insulating redistribution layer, and a second spiral trace layer disposed in the inter-metal dielectric layer correspondingly formed below the first spiral trace layer, wherein the inter-metal dielectric layer has a separating region to divide the second spiral trace layer into a plurality of line segments, and wherein each of a plurality of first slit openings and each of a plurality of second slit openings pass through a corresponding line segment, and extend in an extending direction of a length of the corresponding line segment.

Abstract: An electronic component includes a wire winding wound around a central axis. The wire winding having first and second ends, and first and second terminals are connected to or formed by the first and second ends. The terminals provide electrical contacts for connecting the component into a circuit. The component has a wet press molded body made of a mixture of magnetic and non-magnetic material that is heated and pressed about the wire winding. The wet press molded body leaves at least a portion of the terminals exposed for mounting the component to the circuit.

Abstract: Provided is a chip inductor and manufacturing method thereof. The chip inductor includes: a pin layer, a plurality of insulating layers and a plurality of metal layers, where the insulating layers and the metal layers are arranged successively and alternately on the pin layer. Multiple patterned metal structures arranged in the plurality of metal layers are respectively electrically connected to form a multilayer plane spiral coil structure. The multilayer plane spiral coil structure has two ends electrically connected with respective pin structures in the pin layer.

Abstract: A magnetic micro-device and process to manufacture the same is disclosed. The magnetic micro-device has a near-zero conductivity magnetic nanocomposite film layer with a plurality of apertures through which a corresponding plurality of electrical conductors (vias) pass. Due to the near-zero conductivity of the magnetic nanocomposite film layer, the vias are self-insulating. The presence of the magnetic nanocomposite film layer results in greater inductance than that possible with an air core (or core-less) magnetic micro-device. Potential magnetic micro-devices include toroid micro-inductors, solenoid micro-inductors, toroid micro-transformers, and solenoid micro-transformers. Additional potential magnetic micro-devices include generators, motors, electromagnetic switches, and voice coils (for speakers or microphones). The process used to manufacture the magnetic micro-device can be scaled to cost-effectively produce large numbers of the magnetic micro-device.

Abstract: A multilayer inductor component includes an element body, an internal conductor, and an external electrode. The internal conductor is disposed in the element body. The external electrode is disposed on a surface of the element body and electrically connected to the internal conductor. The external electrode includes a sintered metal layer and a plating layer. The sintered metal layer is disposed on the surface of the element body. The plating layer covers the sintered metal layer. The sintered metal layer includes a thick portion and thin portions. The thick portion covers the surface of the element body. A plurality of glass particles is dispersed in the thick portion. The thin portions cover glass particles exposed on a surface of the thick portion among the plurality of glass particles and being in contact with the plating layer.

Abstract: Traveling-wave tube amplifiers for high-frequency signals, including terahertz signals, and methods for making a slow-wave structure for the traveling-wave tube amplifiers are provided. The slow-wave structures include helical conductors that are self-assembled via the release and relaxation of strained films from a sacrificial growth substrate.

Abstract: An electronic structure comprising: a circuit board, wherein electronic devices and a transformer are disposed on the circuit board, wherein the transformer comprises a first coil, a second coil, and a magnetic body comprising a pillar with at least one portion of the pillar being disposed in a through-opening of the circuit board, wherein the first coil is wound around an upper portion of the pillar and the second coil is wound around a lower portion of the pillar for forming the transformer.

Abstract: A ceramic electronic component has an element body having a dielectric and internal electrodes, and external electrodes formed on the element body. Each of the external electrodes has an electrical conductive layer connected to the internal electrodes. The electrical conductive layer has an outer side and an inner side. The outer side is farther from the element body than the inner side. The outer side includes more voids than the inner side.

Abstract: An EMI filter for an inverter may include a choke including a magnetic inner core, a magnetic outer core, and at least one conductor pair. The at least one conductor pair may include an electrically conductive positive conductor and an electrically conductive negative conductor. The inner core, the outer core, the positive conductor, and the negative conductor may extend along a longitudinal central axis of the choke. The inner core may be arranged in the outer core. The positive conductor and the negative conductor may be arranged between the inner core and the outer core. The positive conductor and the negative conductor may be arranged spaced apart from one another in a circumferential direction extending around the longitudinal central axis. A gap may be formed between the inner core, the outer core, the positive conductor, and the negative conductor, which are adjacent in the circumferential direction.

Abstract: A semiconductor package includes a VLSI semiconductor die and one or more output circuits connected to supply power to the die mounted to a package substrate. The output circuit(s), which include a transformer and rectification circuitry, provide current multiplication at an essentially fixed conversion ratio, K, in the semiconductor package, receiving AC power at a relatively high voltage and delivering DC power at a relatively low voltage to the die. The output circuits may be connected in series or parallel as needed. A driver circuit may be provided outside the semiconductor package for receiving power from a source and driving the transformer in the output circuit(s), preferably with sinusoidal currents. The driver circuit may drive a plurality of output circuits. The semiconductor package may require far fewer interface connections for supplying power to the die.

Abstract: In a coil component, a main body portion is made of a metal magnetic powder-containing resin, and thus a resin component appears on end surfaces of the main body portion. In addition, since external terminal electrodes are made of a conductive resin, a resin component also appears on the surfaces of the external terminal electrodes. Accordingly, insulating coating layers are integrally covered with high adhesion with the end surfaces of the main body portion and the external terminal electrodes by the insulating coating layers coming into contact with the end surfaces of the main body portion so as to straddle the external terminal electrodes.

Abstract: An inductor component comprising a spiral wiring wound on a plane; a first magnetic layer and a second magnetic layer located at positions sandwiching the spiral wiring from both sides in a normal direction relative to the plane on which the spiral wiring is wound; a vertical wiring extending from the spiral wiring in the normal direction to pass through the first magnetic layer; and an external terminal disposed on a surface of the first magnetic layer to connect an end surface of the vertical wiring. The first magnetic layer has magnetic permeability lower than that of the second magnetic layer.

Abstract: An electricity meter (17) is described which includes a conductor (19) for transferring energy from a supply (20) to a load (21). The electricity meter (17) also includes a multi-layer printed circuit board (18) mechanically attached to the conductor (19). The multi-layer printed circuit board (18) includes two or more insulating layers (26, 27, 33, 34). The two or more insulating layers (26, 27, 33, 34) include a first insulating layer (26, 27) having an attachment surface (28) facing the conductor (19). The multi-layer printed circuit board (18) also includes a first conductive layer (29) including a first planar sensor coil (30). The first insulating layer (26, 27) is between the first conductive layer (29) and the conductor (19). The multi-layer printed circuit board (18) also includes a second conductive layer (31) including a second planar sensor coil (32).

Abstract: A method for manufacturing a coil component comprises: forming a coil conductor including a winding portion, the winding portion including a plurality of first conductor portions and one or more second conductor portions smaller in number than the first conductor portions, the first and second conductor portions alternate with and connected to each other; forming a molded body by molding composite magnetic material including metal magnetic particles and a binder with the coil conductor being disposed inside the composite magnetic material; and heating the molded body to produce a magnetic base body. The magnetic base body is formed such that a distance between the first conductor portions and a first surface of the magnetic body is greater than a distance between the second conductor portions and a second surface of the magnetic base body opposite to the first surface, by molding, cutting or polishing.

Abstract: A device includes a first inductor and a second inductor reversely coupled with the first inductor. The first and second inductors have overlapping windings. The device also includes a housing for the first and second inductor. The housing is filled with a magnetic molding compound.

Abstract: An inductance apparatus includes a first winding comprising a first wire section and a second wire section. The first wire section and the second wire section are disposed in a first horizontal plane associated with a center axis, and the first winding is associated with an equivalent current flow path within the first horizontal plane; a second winding extends via the center axis in the first horizontal plane to the first wire section and the second wire section, wherein the equivalent current flow path of the first winding is aligned with a current flow path associated with the second winding.

Abstract: A multilayer coil component includes an element body including a plurality of metal magnetic particles, and a plurality of coil conductors. The plurality of coil conductors is disposed in the element body. The plurality of coil conductors is separated from each other in a predetermined direction and electrically connected to each other. The plurality of coil conductors includes one pair of side surfaces opposing each other in the predetermined direction. Surface roughness of the one pair of side surfaces is less than 40% of an average particle size of the plurality of metal magnetic particles.

Abstract: A laminated transformer can include: a plurality of magnetic layers; a plurality of coil layers including a primary coil having a first type of coil layer, and a secondary coil having a second type of coil layer, where each coil layer is laminated between a pair of the plurality of magnetic layers; and a plurality of non-magnetic layers, where a first of the plurality of non-magnetic layers is disposed between an adjacent pair of the coil layers in order to increase a coupling coefficient between the primary and secondary coils.

Abstract: A common-mode choke coil includes a multilayer body, a first coil, and a second coil. The multilayer body includes plural stacked non-conductor layers. The first and second coils are incorporated in the multilayer body. The first coil includes a first coil conductor. The second coil includes a second coil conductor disposed along an interface between non-conductor layers different from an interface between non-conductor layers along which the first coil conductor is disposed. With the first coil conductor and the second coil conductor being viewed in plan in the stacking direction of the multilayer body, the first coil conductor and the second coil conductor have no portion where the two coil conductors overlap each other, except for a portion where the two coil conductors cross each other.

Abstract: A common-mode choke coil includes a multilayer body, a first coil, a second coil, a first terminal electrode, a second terminal electrode, a third terminal electrode, and a fourth terminal electrode. The multilayer body includes plural non-conductor layers. The first and second coils are incorporated in the multilayer body. The first and second terminal electrodes are connected to the first coil. The third and fourth terminal electrodes are connected to the second coil. The first coil has a path length L1, the second coil has a path length L2, and the sum of the path length L1 and the path length L2 is less than or equal to 3.5 mm.

Abstract: In a coil 5 of a multilayer coil component 1, an end portion 6a of a turn 6 closest to a side surface 2e in the facing direction of the side surface 2e and a side surface 2f is connected to a first external electrode 3 and an end portion 11a of a turn 11 closest to the side surface 2f in the facing direction is connected to a second external electrode 4. When viewed from the facing direction, the area of the region where the turn 6 and the second external electrode 4 face each other and the area of the region where the turn 11 and the first external electrode 3 face each other are larger than the area of the region where turns other than the turn 6 and the turn 11 and the first external electrode 3 or the second external electrode 4 face each other.

Abstract: One aspect of the present invention provides a coil component including a base body having a first surface extending along a coil axis and a second surface opposing the first surface, a first external electrode provided on the base body, a second external electrode provided on the base body, and a coil conductor electrically connected to the first and second external electrodes, where the coil conductor extends around the coil axis. In one embodiment, the coil conductor has a winding portion, the winding portion has a plurality of first conductor portions and one or more second conductor portions smaller in number than the first conductor portions, and the first and second conductor portions alternate with and are connected to each other, and a distance between the first conductor portions and the first surface is greater than a distance between the second conductor portions and the second surface.

Abstract: A printed circuit board according to an embodiment of the present invention includes a core layer and a circuit wiring layer disposed on a top surface of the core layer. The core layer is spaced apart from the circuit wiring layer and includes through-holes formed around the circuit wiring layer. Flexibility of the printed circuit board may be enhanced by the through-hole to obtain bending stability.

Abstract: A common-mode choke coil includes a multilayer body, a first coil, and a second coil. The multilayer body is a cuboid in shape that includes plural stacked non-conductor layers. The first and second coils are incorporated in the multilayer body. The first coil includes a first coil conductor, and the second coil includes a second coil conductor. The first coil conductor is positioned with gaps SG1 to SG4 interposed between the first coil conductor and the outer periphery surface of the multilayer body. The second coil conductor is positioned with gaps SG5 to SG8 interposed between the second coil conductor and the outer periphery surface of the multilayer body. Of the four absolute values of the differences between the gaps SG1 to SG4 and the corresponding gaps SG5 to SG8, at least two absolute values are greater than or equal to 0.02 mm.

Abstract: An inductor according to one embodiment includes: a base body having a mounting surface, a top surface, and a first end surface; first and second external electrodes provided to the mounting surface and spaced from each other; and an conductor disposed inside the base body. One end of the conductor is exposed from the mounting surface and connected to the first external electrode, and the other end of the conductor is exposed from the mounting surface and connected to the second external electrode. The base body is partitioned into a first region and a second region, the first region being enclosed by the conductor and the mounting surface, and a ratio of an area of the second region to an area of the first region is 0.95 to 1.0. The conductor contains a conductive material having a higher electric conductivity than a material of the first external electrode.

Abstract: A coil structure includes metal plates each including a spiral conductor, and a row of terminals, aligned in a predetermined direction on an outer side of the conductor, and formed by plate portions thicker than the conductor. Two ends of the conductor are connected to two adjacent plate portions for each metal plate. The row of terminals of a first metal plate is bonded to the row of terminals of a second, adjacent metal plate. The position where the two ends of the conductor connect to the two adjacent plate portions shifts one place toward the second end for each upward increase in level within a laminate along a laminated direction of the metal plates, so that the conductors of each of the metal plates are connected in series to form a spiral coil.

Abstract: An inductor component includes a body that includes a magnetic layer, an inductor wire that is provided in the body, and a vertical wire that is provided in the body and that extends to a first principal surface from a contact portion of the vertical wire that is in contact with the inductor wire. The vertical wire is in contact with the inductor wire in such a manner as to extend over a first side surface and a third side surface of the inductor wire.

Abstract: A microcoil element, an array-type microcoil element and a device are provided. The microcoil element includes a wiring layer having continuous multiple metal line segments that form multiple loops around a starting point of the element. Every metal line segment includes a first electrode end and a second electrode end. The microcoil element includes an electrode layer having a first electrode zone and a second electrode zone that respectively collect the first electrode ends and the second electrode ends of the multiple metal line segments. When designing the microcoil element, parameters such as a total length of the multiple line segments, a line width, a line spacing of adjacent line segments, a length of each line segment, turns of the microcoil, and a loop distance according to impedance requirement. The single microcoil element or the array-type microcoil element can be used as a magnetic component of a device.

Abstract: In an adhesively-laminated core for a stator, a chemical component of each of electrical steel sheets includes 2.5% to 3.9% by mass of Si, an average tensile modulus of elasticity of each of adhesion parts is 2500 MPa to 5000 MPa, and when an average sheet thickness of the each of electrical steel sheets is t1 in units of mm, an average thickness of the each of adhesion parts is t2 in units of ?m, and an average value of yield strengths of the each of electrical steel sheets is YP in units of MPa, a condition A of satisfying the following expressions 1, 2, and 3 or a condition B of satisfying the following expressions 3, 4, and 5 or combination thereof is satisfied. 50×t1?12?t2?50×t1?6??(expression 1) 0.15?t1?0.27??(expression 2) 0.5?t2?2.5??(expression 3) 0.025×YP?12?t2?0.

Abstract: A configurable micro-acoustic RF filter comprises first and second filter subsections (140, 150) and at least one switch (160) to selectively bypass or activate the second filter subsection (150). The filter sections include at least one serially connected and at least one shunt connected micro-acoustic resonator.

Abstract: An inductor device includes a first trace, a second trace, and a capacitor. The first trace includes at least two sub-traces. One terminal of each of the at least two sub-traces are coupled to each other at a first node. The second trace includes at least two sub-traces. One terminal of each of the at least two sub-traces are coupled to each other at a second node. The capacitor is coupled to the firs node and the second node.

Abstract: A coil component includes a body, a coil portion disposed in the body and having first and second lead-out portions exposed to at least one surface of the body to be spaced apart from each other, first and second external electrodes disposed on the at least one surface of the body to be spaced apart from each other, and respectively connected to the first and second lead-out portions, a dielectric layer disposed on a surface of the body, and a third external electrode disposed on the surface of the body having the dielectric layer disposed thereon to be spaced apart from each of the first and second external electrodes, and covering the dielectric layer.

Abstract: A filter assembly is disclosed that includes a monolithic filter having a surface and a heat sink coupled to the surface of the monolithic filter. The heat sink includes a layer of thermally conductive material that can have a thickness greater than about 0.02 mm. The heat sink may provide electrical shielding for the monolithic filter. In some embodiments, the filter assembly may include an organic dielectric material, such as liquid crystalline polymer or polyphenyl ether. In some embodiments, the filter assembly may include an additional monolithic filter.

Abstract: A coil component includes a body, a support portion disposed in the body, a coil portion disposed on a first surface of the support portion, a lead portion disposed on a second surface of the support portion facing the first surface of the support portion and connected to the coil portion, and a via penetrating through the support portion to connect an inner end portion of the coil portion and an inner end portion of the lead portion to each other, wherein the coil portion includes a first conductive layer embedded in the support portion and having a first surface exposed to or facing the first surface of the support portion, a second conductive layer disposed on the first surface of the first conductive layer, and a third conductive layer disposed on the second conductive layer and protruding from the first surface of the support portion.

Abstract: A coil component includes spiral conductor patterns S1 and S2 and insulating resin layers that cover the spiral conductor patterns S1 and S2, respectively. An outermost turn of the spiral conductor pattern S1 has a widened part. As a result, an outer wall surface part constituting the outer wall surface of the outermost turn in the radial direction and an outer wall surface part constituting the outer wall surface of the outermost turn of the spiral conductor pattern S2 in the radial direction differ in radial position from each other. Overlap of the insulating resin layers in the lamination direction is reduced to suppress thermal expansion or contraction of the insulating resin layers in the lamination direction at the overlap. This can relieve a stress applied to the interface between the spiral conductor pattern and the insulating resin layer.

Abstract: A filter and array of filters providing inductive coupling are disclosed. According to one aspect, an RF filter includes a plurality of dielectric layers with a first ground plane on one side of the dielectric layers and a second ground plane on an opposite side of the dielectric layers. One of the first and second ground planes provides an input port and one of the first and second ground planes provides an output port. Two parallel strip line resonators, lie in a first plane parallel to, and between, the first and second ground planes, the two parallel strip line resonators, having a gap there between. An inductive coupling plate in proximity to the gap, is grounded at an edge and lies in a second plane, the second plane parallel to the first plane and lying between the first plane and one of the first and second ground planes.

Abstract: A coil component includes a body having a core, a coil portion disposed in the body and having a central portion in which the core is disposed, a first external electrode and a second external electrode, each connected to the coil portion, a third external electrode spaced apart from each of the first and second external electrodes, and a noise removal portion disposed to at least partially surround the coil portion between a surface of the body and the core and having both end portions, each connected to the third external electrode.

Abstract: A structure comprises a semiconductor integrated circuit, an inductor, and a magnetic flux closure layer. The inductor is integrated into a multilevel wiring network in the semiconductor integrated circuit. The inductor includes a planar laminated magnetic core and a conductive winding that turns around in a generally spiral manner on the outside of the planar laminated magnetic core. The planar laminated magnetic core includes an alternating sequence of a magnetic layer and a non-magnetic layer. The magnetic flux closure layer is disposed within about 100 ?m of a face of the planar laminated magnetic core, the face of the planar magnetic core parallel to a principal plane of the planar laminated magnetic core. A second magnetic flux closure layer can be disposed within about 100 ?m of an opposing face of the planar laminated magnetic core.

Abstract: The present invention pertains to a transformer, and more specifically, to a transformer which includes a primary coil unit comprising wound conductive lines, and a secondary coil unit in which conductive plates are stacked. The transformer according to an embodiment of the present invention may include: a bobbin; a core unit which is coupled to the bobbin along the outer side of the bobbin; and a plurality of conductive plates which are inserted into the bobbin and stacked in the thickness direction.

Abstract: A planar array coil includes a multilayer substrate at which a plurality of coils are formed and arranged on a plane of the multilayer substrate. First ends of the plurality of coils are connected to switching circuit units of a power conversion circuit, and second ends of the plurality of coils are connected to a common output part. The coils include two coil parts in which currents flow in opposite rotation directions, and one coil part of one coil is adjacent to one coil part of another coil. The plurality of coils are connected such that operation of switching circuits causes currents in regions of adjacent coil parts that extend in parallel to each other to flow in the same direction. Accordingly, adverse effects by unwanted coupling between adjacent coils are reduced and a switching power supply device that includes the planar array coil performs stable power conversion operations.