JPH045806A - Spiral inductor - Google Patents

Abstract

PURPOSE:To obtain a large inductance by a method wherein a spiral conductive- film interconnection is formed on the rear surface corresponding to a blank part at a spiral interconnection on the surface side and both are connected via through holes so as to strengthen a mutual inductance. CONSTITUTION:A spiral inductor 1 on the surface of a substrate is formed of a conductive interconnection; it is connected to a spiral inductor 3 on the rear surface via a through hole 2 in the central part. The inductor 3 is formed in a position corresponding to a blank part at a line interval of the inductor 1; it is extracted to the surface from a through hole 4 at an extraction end. As an inductance between both end parts, the winding direction is in the peripheral direction, both inductors on the surface and the rear surface help each other, and an inductance amount of two times or higher can be obtained in the same occupied area.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hybrid integrated circuit including an inductor, and more particularly to a spiral inductor formed on a hybrid integrated circuit board using conductive film wiring.

[Conventional technology]

As shown in the plan view of FIG. 3, the conventional spiral inductor has a conductive film wiring 11 formed in a spiral shape on the upper surface of a substrate, and is connected to a lower surface connection wire 5 through a through hole 2 in the center. The lower surface connection line 5 linearly passed under the upper surface spiral wiring, was connected to the through hole 4, and was connected to the upper surface again through the through hole 4.

[Problem to be solved by the invention]

This conventional spiral inductor is formed with spiral conductive film wiring only on the top surface, and has the disadvantage that it occupies a large area on the substrate in order to obtain a large inductance.

[Means to solve the problem]

In the spiral inductor of the present invention, when an inductor is formed using conductive film wiring on a hybrid integrated circuit board, the spiral inductor is formed not only on one surface of the top or bottom surface, but also with the line spacing of the spiral wiring of the spiral inductor formed on the top surface side. Spiral conductive film wiring is formed on the lower surface corresponding to the blank area, and connected through through holes in a direction in which mutual inductance is strengthened.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a plan view of a spiral inductor according to an embodiment of the present invention. In the figure, J is a spiral inductor on the upper surface of the substrate, which is made of conductive film wiring formed in a spiral shape. It is connected to a spiral inductor 3 on the lower surface via a through hole 2 in its center. The spiral inductor 3 on the bottom surface has wiring formed at a position corresponding to the blank space between the lines of the spiral inductor on the top surface, and the winding direction from the center to the outside is the same as that on the top surface side, and the wiring is formed at the position corresponding to the blank space between the lines of the spiral inductor on the top surface. It is pulled out from the through pole 4 to the upper surface. Since the winding directions are the same, the inductance between the two ends is mutually supported, and more than twice the inductance can be obtained in the same occupied area.

FIG. 2 is a plan view showing an application example. In FIG. 2, the connection at the center of FIG. 1 is turned off, and the inductors 1 and 3 on the top and bottom surfaces form a coupler that is insulated from each other. The area occupied by this coupler can also be reduced.

〔Effect of the invention〕

As explained above, the present invention provides a spiral inductor with conductive film wiring on the upper and lower surfaces of the substrate so that the wiring of the lower spiral inductor is located on the lower surface side of the blank space between the lines of the spiral inductor on the upper surface of the substrate. form,
By connecting both inductances with through holes so as to strengthen each other, the inductance of only one layer is more than twice as large as that of a single layer spiral inductor with only the top or bottom surface, while occupying the same area. This has the effect of obtaining a large inductance.

[Brief explanation of drawings]

FIG. 1 is a plan view of an embodiment of the present invention, FIG. 2 is a plan view of an applied example of the present invention, and FIG. 3 is a plan view of a conventional spiral inductor. 1...Top inductor, 2, 4...Through hole, 3...Bottom inductor, 5...
...Bottom connection line, 11...Spiral conductive film wiring.

Claims (1)

[Claims] A top spiral inductor formed by a spiral conductive film wiring on the top surface of the substrate, a bottom spiral inductor formed on the bottom surface of the substrate at a position corresponding to a blank space between lines of the top spiral inductor, and inductances of the top and bottom inductors. 1. A spiral inductor characterized by having a through hole in which both are connected in series in a direction in which they are strengthened.