BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an element that connects two circuits, and particularly to an inductor bridge including an inductance component and an electronic device including the inductor bridge.

2. Description of the Related Art

Conventionally, in a small electronic device such as a mobile terminal, in the case in which members of a mounting circuit, such as a plurality of boards, are provided in a casing, for example, as disclosed in WO 2014/129279, the members of the mounting circuit are connected to each other by a flat cable having flexibility.

FIG. 9is an exploded perspective view illustrating one inductor bridge of WO 2014/129279. The inductor bridge includes a flat plate-shape element body having flexibility, a first connector51, and a second connector52. The element body is formed by laminating resin bases11,12,13,14. Connector mounting electrodes41,42, a wiring pattern21, and a wound conductor pattern31are formed on the resin base11. Wound conductor patterns32,33are formed on the resin bases12,13, respectively. A wiring pattern23and a wound conductor pattern34are formed on the resin base14. Resist layers61,62are formed on top and bottom surfaces of the element body.

The inductor bridge disclosed in WO 2014/129279 has the flexible, flat plate-shaped element body formed by a lamination of a plurality of resin bases, an inductor is formed in the element body, and a first connection unit connected to a first circuit and a second connection unit connected to a second circuit are provided on a first surface of the element body.

The flexible inductor bridge disclosed in WO 2014/129279 is often provided in a restricted space inside the electronic device while being bent at a predetermined location thereof. However, when the inductor bridge is bent at a location at which the inductor is formed, sometimes an electric characteristic, such as inductance, may change before and after bending. On the other hand, when the inductor bridge is bent at the wiring pattern, although the electric characteristic is slightly changed, disconnection of the wiring pattern or peeling of the conductor pattern from the resin base is easily generated due to the bending.

SUMMARY OF THE INVENTION

As described above, the inventors of the present invention have discovered that there is a problem in that the electrical reliability is hardly secured even if the inductor bridge is bent in any one of the inductor and the wiring unit.

Preferred embodiments of the present invention provide highly reliable inductor bridges and electronic devices, which are each capable of downsizing or miniaturizing the electronic device including an electronic circuit including the inductor.

According to a preferred embodiment of the present invention, an inductor bridge, which is an element that bridge-connects a first circuit and a second circuit, includes a flat plate-shaped element body having flexibility and including a plurality of resin bases that are laminated; a first connection unit provided on a first surface of the element body and connected to the first circuit; a second connection unit provided on the first surface and connected to the second circuit; an inductor electrically connected between the first connection unit and the second connection unit and provided in the element body; and a wiring unit connected in series to the inductor. The inductor includes wound conductor patterns, each of which has a winding axis in a laminating direction of the plurality of resin bases and is respectively provided on each of the plurality of resin bases, and an interlayer connection conductor interlayer-connecting the wound conductor patterns, and the wiring unit includes a wiring pattern and a plurality of interlayer connection conductors connected to the wiring pattern, the wiring pattern being provided at a single layer or a plurality of layers, the single layer or the plurality of layers being different from the first surface and a layer of the wound conductor pattern farthest from the first surface, and being located between the first surface and the layer farthest from the first surface.

With the above-described configuration, the wiring pattern of the wiring unit in the element body is prevented from being peeled off. The interlayer connection conductor is hardly broken. Thus, the disconnection and the peeling of the wiring pattern due to stress during bending of the wiring unit are reduced or prevented.

The wiring pattern may be provided in a plurality of layers, and the wiring pattern and the interlayer connection conductor may be disposed stepwise from a layer closest to the layer farthest from the first surface to a layer close to the first surface. Consequently, the interlayer connection conductors are not laminated at the same location and are dispersedly disposed, so that the disconnection and the peeling of the wiring pattern due to the stress during the bending are more effectively prevented.

The wiring pattern may include a wiring pattern portion that overlaps the wound conductor pattern in planar view and a conductor pattern that does not overlap the wound conductor pattern in planar view, and the wiring pattern portion that overlaps the wound conductor pattern may be located farther from the wound conductor pattern than the conductor pattern that does not overlap the wound conductor pattern in the laminating direction. Consequently, unnecessary parasitic capacitance generated between the wound conductor pattern and the wiring pattern is prevented. The wiring pattern, which does not overlap the wound conductor pattern in planar view but is located at a bending position, is located close to a middle height of a laminated body, so that disconnection or peeling due to the bending is more reliably prevented.

The element body may include a bending portion that is bent at a position at which the wiring pattern is provided. Consequently, the stress applied to the inductor is reduced, and electrical reliability is improved.

According to a preferred embodiment of the present invention, an electronic device includes the inductor bridge according to a preferred embodiment of the present invention; a first circuit; and a second circuit. The first circuit and the second circuit are connected to each other with the inductor bridge interposed therebetween.

With the above-described configuration, the electronic device including the inductor bridge with high electrical reliability is obtained.

According to preferred embodiments of the present invention, highly reliable inductor bridges and electronic circuits each including an inductor bridge are obtained.

The above and other elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings.

