Murata Manufacturing Co., Ltd.

Takahiro Okada

Hideyuki Kato

Jinsei Ishihara

Hitoshi Tada

Katsuhito Kuroda

Hideki Tsukamoto

Masayuki Atokawa

Takayoshi Yui

Yoshiki Yamada

Nobumitsu Amachi

Masayuki Kikuda

Kazushige Sato

Takafumi Kanno

A circuit module () includes a circuit board () having a main surface (), an electronic component () mounted on the main surface (), and a sealing resin () covering at least part of the electronic component () on the main surface (). A recess () is formed on at least part of a side surface () of the sealing resin (). At least the recess () is covered with an electrically conductive film ().

Circuit module and manufacturing method therefor

A filtering device includes at least one dielectric resonant element, which includes a dielectric block, an outer conductor, and an inner conductor, a terminal disposed in a through hole of the dielectric resonant element from a front surface, a plate-shaped circuit element electrically coupled with the at least one dielectric resonant element via the terminal, and a substrate on which the at last one dielectric resonant element and the plate-shaped circuit element are mounted. The outer conductor is disposed so as to cover the back surface besides the peripheral surface of the dielectric block. The first end surface of the dielectric block includes a first electrode-free portion that electrically isolates the inner conductor from the outer conductor, and a second electrode-free portion that electrically isolates the inner conductor from the outer conductor.

Filtering device and method for adjusting filter characteristic

A dielectric filter having a dielectric block disposed on a mount board. The dielectric block includes inner conductor holes having open ends on the front surface of the dielectric block. Input/output electrodes are disposed on the undersurface of the dielectric block. Each of the input/output electrodes extends from the boundary between a side surface and the undersurface of the dielectric block to the boundary between the front surface and the undersurface of the dielectric block. An outer conductor includes undersurface electrode corner portions and an undersurface electrode main portion. Each of the undersurface electrode corner portions is disposed at a corner formed by the front surface and one of the side surfaces of the dielectric block.

Dielectric filter having a dielectric block with input/output electrodes of a bent shape at corner portions of the block

A dielectric filter having inner-conductor holes penetrating through a dielectric block from a first surface to a second surface thereof. An outer conductor and input/output electrodes are formed on an outer surface of the dielectric block. A side of each of the input/output electrodes facing the first surface is substantially in parallel to the first surface, and an intersection of a side facing the second surface and a side facing a sixth surface is tapered. With such a configuration, an attenuation characteristic at an attenuation band is improved by making the attenuation characteristic less likely to receive an influence of a TE mode.

Dielectric filter having tapered input/output electrodes

A method of forming a dielectric resonator from an inner-conductor-formed hole that has a substantially rectangular or substantially elliptical cross section in a direction perpendicular to the depth direction thereof, by placing a rotary cutting disk in contact with the edge of the opening of the inner-conductor-formed hole, and removing portions of an outer conductor and the inner conductor in the contact portion with the rotary cutting disk, thereby separating the inner conductor and the outer conductor.

Production method for dielectric resonator device

In a dielectric filter, from the top surface to the bottom surface of a substantially rectangular dielectric block, inner-conductor holes are formed. On the inner surfaces of the inner-conductor holes, inner conductors are formed except where non-conductor portions are formed in proximity to one of the top and bottom surfaces, in which the apertures of the inner-conductor holes are formed. On the outer surface of the dielectric block, an outer conductor is formed substantially over the entire outer surface, and input and output electrodes isolated from the outer conductor are coupled with the non-conductor portions in the respective inner-conductor holes at the ends of the dielectric block in the direction of array of the inner-conductor holes. In one of the surfaces in which the apertures of the inner-conductor holes are formed, or in one of the surfaces at the ends of the dielectric block in the direction of array of the inner-conductor holes, a concavity is formed, the inner surface thereof being covered with the outer conductor.

Dielectric filter, dielectric duplexer, and communication apparatus

A dielectric filter and a dielectric duplexer have structures for coupling between resonators, in which a range for determining the coupling strength between the resonators can be broadened and the polarity of the coupling can be changed. In addition, a communication apparatus incorporating the dielectric filter or the dielectric duplexer can be provided. Inside a dielectric member, resonance line holes having resonance lines formed on the inner surfaces thereof are disposed. Both ends of each of the resonance line holes are open-circuited. The inner diameter of each of the resonance line holes is changed at some point in the longitudinal direction of each resonance line to form a stepped part.

Dielectric filter, dielectric duplexer, and communication apparatus incorporating the same

A dielectric filter capable of easily obtaining desired filter characteristics by strongly coupling mutually adjacent resonators with high accuracy even when reducing the height of the entire filter. In this filter, inside a dielectric block, there are disposed inner-conductor-formed holes in which inner conductors are formed on the inner surfaces of the holes. Coupling electrodes are arranged on an outer surface of the dielectric block and are electrically connected to the inner conductors. Additionally, the coupling electrodes are extended, for example, from the edge of an opening surface of the dielectric block which contains the open ends of the inner-conductor-formed holes, onto a side surface which is disposed parallel to a direction in which the inner-conductor-formed holes are aligned. The invention also provides a duplexer and a communication apparatus using the dielectric filter.

The invention provides a composite dielectric filter device that can easily improve the isolation characteristics between mutually adjacent filters, even when using a compact dielectric block to miniaturize the entire configuration of the device. The invention also provides a communication apparatus incorporating the filter device. In the filter device, inner conductor holes are arranged inside a single dielectric block, and an outer conductor is formed on outer faces of the dielectric block. Additionally, an outer-conductor-free portion is formed at the boundary between a transmission filter and a reception filter formed by the inner conductor holes.

Composite dielectric filter device and communication apparatus incorporating the same

A dielectric duplexer includes a substantially rectangular dielectric block. The dielectric block includes inner-conductor-containing holes each having an inner conductor on the inner surfaces thereof, and inner-conductor-unformed portions on which the inner conductors are not formed are formed in the vicinity of first ends of the inner-conductor-containing holes. The dielectric block further includes an outer conductor and input/output electrodes which are formed on the outer surface thereof, and the input/output electrodes are separated from the outer conductor. A through-hole having a short circuited electrode formed on the inner surface thereof is provided between two of the inner-conductor-containing holes so as to run from the mounting surface to the surface opposite thereto.

Dielectric duplexer and communication apparatus

A stepped portion is formed inside the inner-conductor holes arranged between both side surfaces of a dielectric block. The axis at an open end of the holes is made to be different from the axis at a short-circuited surface. The open ends of the inner-conductor holes are formed so as to be close to corresponding input-output electrodes.

A dielectric filter and a dielectric duplexer with improved out-of-band attenuation characteristics in the vicinity of the pass band without changing the pass band characteristics. Inner conductor forming holes are formed from one end face to the opposite end face of a dielectric block, and inner conductors are formed on the respective inner surfaces. An outer conductor is formed over substantially the entire outer surface of the dielectric block. On one side surface of the dielectric block, substantially parallel to the inner conductors, outer conductor gaps are provided in at least one area disposed between a pair of inner conductors, extending between the opposite end faces.

Dielectric filter, dielectric duplexer, and communication system

The reflection loss characteristic of a dielectric filter provided with a plurality of stages of resonators is measured, pole frequencies and a balance of heights of peaks in the reflection loss characteristic are sought, and, based on the pole frequencies and the balance of peaks, the part of the filter to be adjusted and the degree of adjustment are determined with reference to a database constructed in advance.

Growing community of inventors

Ishikawa-ken, Japan

Takahiro Okada