Kyocera Corporation

Wataru Koga

Takanori Ikuta

Yuuko Yokota

Kiyohiro Iioka

Yoshifumi Yamagata

Motoki Ito

Shigehiko Nagamine

Masayuki Funami

Takeshi Takenoshita

Mitsutaka Shimada

Motoki Itou

Shinichiro Kitanishi

Hiroki Kan

The branching filter has the piezoelectric substrate having the main surface on which there are formed a transmission filter, which includes an input electrode and an antenna electrode, and a reception filter, which includes an output electrodes and the antenna electrode. The branching filter also has the mounting substrate having, on a first main surface, a first electrode group that is connected to the transmission filter and reception filter and that is formed symmetrical with respect to a line when viewed from the above, and also having, on a second main surface locating on the opposite side to the first main surface, a second electrode group that is connected to the circuit interconnects of an external circuit board and that is formed symmetrical with respect to a line when viewed from the above.

Electronic device

Provided is a demultiplexer capable of improving attenuation characteristic and isolation characteristic of a filter having a lower transmission frequency band among two filters having different transmission frequency bands, outside the transmission frequency band of a high-frequency side. A communication device using the demultiplexer is also disclosed. A first spiral wiring portion () and a sixth wiring portion () are formed so that an angle defined by a direction of a part (L) of the first spiral wiring portion () and a direction of a part (L) of the sixth spiral wiring portion () on a predetermined virtual plane is, for example, 0 degree and the direction of the current flowing in the part (L) of the first spiral wiring portion () is opposite to the direction of the current flowing in the part (L) if the sixth wiring portion ().

Duplexer and communication device

Terminal electrodesfor carrying a high frequency deviceare formed on a surface of a circuit board having its reverse surface covered with a reverse surface conductor layer, and a plurality of signal linesfor exchanging a signal between the high frequency deviceand an external circuit are formed thereon. The terminal electrodeis arranged at the center of the circuit board, and the signal linesradially extends from the terminal electrode. Electromagnetic interference between the signal linescan be reduced, so that out-of-band attenuation characteristics and isolation characteristics can be satisfactorily exhibited in a case where the high frequency deviceis a duplexer.

High frequency device mounting substrate and communications apparatus

After electrode patterning on an electrode forming surface of a piezoelectric substrate(FIG.()), a conductor layer is formed on an electrode non-forming surface of the piezoelectric substrate(FIG.()). After forming the conductor layer, the conductor layer formed on the other surface is removed (FIG.()) after at least one step (FIG.()), and thereafter, dicing for separation into elements and mounting on a mounting substrate are carried out. By removing all the conductor layer on the other surface of the piezoelectric substrate, the out-of-passband attenuation and isolation performance can be significantly improved.

Surface acoustic wave device manufacturing method, surface acoustic wave device, and communications equipment

In a surface acoustic wave device, an excitation electrodein a surface acoustic wave element is provided on a lower surface of a piezoelectric substrate, and the lower surface of the piezoelectric substrateis disposed in a state where it is opposed to an upper surface of a mounting base member. The surface acoustic wave device comprises a through holepenetrating between the upper surface and a lower surface of the mounting base member, a lead electrodeclosing the through holeand formed so as to extend to the lower surface of the mounting base member, and an insulatorcovering the lead electrodeso as to expose its partial area. When the surface acoustic wave device is mounted on a circuit board or the like, therefore, the through holeis closed by the insulator, so that no bubbles are produced in the through hole, and cracks can be prevented from appearing, thereby making it possible to provide a highly reliable surface acoustic wave device having no inferior connection or the like.

Surface acoustic wave device and electronic circuit device

An IDT electrodeand an electrode padare formed on one principal face of a piezoelectric substrateand a circular electrodeis formed so as to surround these components. The circular electrodeis connected to a radiating conductorformed on a bottom face of a circuit boardthrough a via conductorformed within the circuit board. Thus, since heat generated in the IDT electrodeis easy to be released to the outside through the circular electrode, the via conductorand the radiating conductor, adverse effects due to the heat can be prevented, thereby improving high power durability.

Surface acoustic wave apparatus and communications equipment

A conductor layeris provided so as to prevent pyroelectric destruction occurring in the steps of manufacturing a surface acoustic wave elementon the other surface opposite to an IDT electrode formation surface of a piezoelectric substrate. At this time, the conductor layeris formed, except for a regionopposed to an input electrode sectionin a filter regionand/or a regionopposed to an output electrode section. This allows a coupling amount between the input electrode sectionand the output electrode sectiondue to a parasitic capacitance formed between the input electrode sectionand the output electrode sectionin the filter regionto be reduced, thereby allowing the out-of-band attenuation characteristics of a surface acoustic wave device to be improved.

Surface acoustic wave device, manufacturing method therefor, and communications equipment

In a surface acoustic wave device according to the present invention, a transmitting filter element TX and a receiving filter element RX are formed on one main surface of a piezoelectric substrate, and are mounted by face down on an upper surface of a circuit board. A ground electrodein the receiving filter element RX is connected to three linear via conductors' formed on the circuit board, and a ground electrodein the transmitting filter element TX is connected to a crank-shaped via conductor&#x2032; formed on the circuit board

Surface acoustic wave device and communication apparatus

A plurality of surface acoustic wave elements, with an IDT electrodeand a pad electrodeformed on the principal surface of a piezoelectric substrate, are formed to be flip-chip mounted on a circuit boardand sealed using sealing resin. The circuit boardis diced integrally with the sealing resinapplying a rotating dicing bladefrom the bottom surface side thereof to produce a plurality of surface acoustic wave devices. The side surfaces of the surface acoustic wave devices can be formed perpendicularly with dimensional accuracy without rounding or chipping an edge portion of the sealing resin

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Kyoto, Japan

Wataru Koga