Matching circuit chip, filter with matching circuit, duplexer and cellular phone

• US 6,326,863 B1
• Filed: 12/18/1998
• Issued: 12/04/2001
• Est. Priority Date: 12/18/1997
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Yuda, Naoki, Ishizaki, Toshio, Yamada, Toru, Nakakubo, Hideaki, Fujikawa, Makoto, Kushitani, Hiroshi
• Primary Examiner(s): Pascal, Robert
• Assistant Examiner(s): Glenn, Kimberly E
• Application Number:
  US09/215,132
• Time in Patent Office: 1,082 Days
• Field of Search: 333/126, 333/129, 333/132, 333/134, 333/128, 455/82, 455/83, 370/278
• US Class Current: 333/128
• CPC Class Codes: H01P 1/2039 Galvanic coupling between Input/Output
• CPC Class Codes: H01P 1/2135 using strip line filters H01P1/2131 takes precedence
• CPC Class Codes: H01P 5/02 with invariable factor of coupling H01P5/12 takes precedence choke joints H01P1/04, H01P1/06

Abstract

The present matching circuit chip has an integrated shape comprising a first transmission line, a second transmission line and a third transmission line, wherein one end of the first transmission line, one end of the second transmission line and one end of the third transmission line are connected to one another, a first filter connection terminal is connected to the other end of the first transmission line, an antenna terminal is connected to the other end of the second transmission line, and a second filter connection terminal is connected to the other end of the third transmission line, whereby the second transmission line converts the characteristic impedances of the first and third transmission lines so that the impedance matching between the antenna terminal and the first filter connection terminal can be attained, and so that the impedance matching between the antenna terminal and the second filter connection terminal can be attained.

Claims

1. A duplexer having a configuration wherein a first shield electrode is disposed on the upper surface of a first dielectric layer, a second dielectric layer is laid (laminated) on said first shield electrode, a first transmission line electrode is disposed on the upper surface of said second dielectric layer, a third dielectric layer is laid on said first transmission line electrode, a plurality of resonator electrodes for a transmitting filter and a plurality of resonator electrodes for a receiving filter are disposed on the upper surface of said third dielectric layer, a fourth dielectric layer is laid on said plural resonator electrodes for said transmitting filter and plural resonator electrodes for said receiving filter, a transmission line electrode for said transmitting filter, a plurality of capacitor electrodes for said transmitting filter and a plurality of capacitor electrodes for said receiving filter are disposed on the upper surface of said fourth dielectric layer, a fifth dielectric layer is laid on said transmission line electrode for said transmitting filter, said plural capacitor electrodes for said transmitting filter and said plural capacitor electrodes for said receiving filter, a second transmission line electrode and a third transmission line electrode are disposed on the upper surface of said fifth dielectric layer, a sixth dielectric layer is laid on said second transmission line electrode and said third transmission line electrode, a second shield electrode is disposed on the upper surface of said sixth dielectric layer, a seventh dielectric layer is laid on said second shield electrode, and at least four end surface electrodes are disposed on the side surfaces of a dielectric comprising said stacked dielectric layers, wherein one end of said first transmission line electrode, one end of said second transmission line electrode and one end of said third transmission line electrode are electrically connected to one another, the other end of said third transmission line electrode is electrically connected to one end of said transmission line electrode for said transmitting filter, said capacitor electrodes for said transmitting filter are disposed so as to be laid over parts of said resonator electrodes for said transmitting filter arranged in parallel, respectively, said capacitor electrodes for said transmitting filter are connected to said transmission line electrode for said transmitting filter, said end surface electrodes connected to the other end of said transmission line electrode for said transmitting filter is used as a transmitting terminal, said resonator electrodes for said receiving filter are disposed in parallel, said capacitor electrodes for said receiving filter are disposed so that parts thereof are laid over both of said resonator electrodes for said receiving filter adjacent to each other, said capacitor electrode for said receiving filter disposed so as to be laid over a part of said resonator electrode for said receiving filter disposed at one end of the arrangement of said plural resonator electrodes for said receiving filter is electrically connected to the other end of said first transmission line, said at least for end surface electrode connected to said capacitor electrode for said receiving filter disposed so as to be laid over a part of said resonator electrode for said receiving filter disposed at the other end of the arrangement of said plural resonator electrodes for said receiving filter is used as a receiving terminal. A third of said at least for end surface electrode connected to the other end of said second transmission line electrode is used as an antenna terminal, and said end surface electrodes connected to said first shield electrode and said second shield electrode are grounded.

2. A duplexer in accordance with claim 1, wherein at least one of said plurality of capacitive electrodes is disposed in said dielectric layers and connected to one of said end surface electrodes.

3. A duplexer in accordance with claim 1, wherein at least one stub line is disposed in at least one of each of said dielectric layers, and said stub line is connected to said antenna terminal, said transmitting terminal, the connection point of said first transmission line electrode, said second transmission line electrode and said third transmission line electrode or the connection point of said third transmission line electrode and said transmission line electrode for said transmitting filter.

4. A duplexer in accordance with claim 1, wherein at least one stub line is disposed in at least one of each of said dielectric layers, and said stub line is connected to said antenna terminal, said receiving terminal, the connection point of said first transmission line electrode, said second transmission line electrode and said third transmission line electrode or the connection point of said first transmission line electrode and said capacitor electrode for said receiving filter.

5. A duplexer having a configuration wherein a first shield electrode is disposed on the upper surface of a first dielectric layer, a second dielectric layer is laid (laminated) on said first shield electrode, a first transmission line electrode is disposed on the upper surface of said second dielectric layer, an eighth dielectric layer is laid on said first transmission line electrode, a third shield electrode is disposed on the upper surface of said eighth dielectric layer, a third dielectric layer is laid on said third shield electrode, a plurality of resonator electrodes for a transmitting filter and a plurality of resonator electrodes for a receiving filter are disposed on the upper surface of said third dielectric layer, a fourth dielectric layer is laid on said plural resonator electrodes for said transmitting filter and plural resonator electrodes for said receiving filter, a transmission line electrode for said transmitting filter, a plurality of capacitor electrodes for said transmitting filter and a plurality of capacitor electrodes for said receiving filter are disposed on the upper surface of said fourth dielectric layer, a ninth dielectric layer is laid on said transmission line electrode for said transmitting filter, said plural capacitor electrodes for said transmitting filter and said plural capacitor electrodes for said receiving filter, a fourth shield electrode is disposed on the upper surface of said ninth dielectric layer, a fifth dielectric layer is laid on said fourth shield electrode, a second transmission line electrode and a third transmission line electrode are disposed on the upper surface of said fifth dielectric layer, a sixth dielectric layer is laid on said second transmission line electrode and said third transmission line electrode, a second shield electrode is disposed on the upper surface of said sixth dielectric layer, a seventh dielectric layer is laid on said second shield electrode, and at least four end surface electrodes are disposed on the side surfaces of a dielectric comprising said stacked dielectric layers, wherein one end of said first transmission line electrode, one end of said second transmission line electrode and one end of said third transmission line electrode are electrically connected to one another, the other end of said third transmission line electrode is electrically connected to one end of said transmission line electrode for said transmitting filter, said capacitor electrodes for said transmitting filter are disposed so as to be laid over parts of said resonator electrodes for said transmitting filter arranged in parallel, respectively, said capacitor electrodes for said transmitting filter are connected to said transmission line electrode for said transmitting filter, a first of said at least four end surface electrode connected to the other end of said transmission line electrode for said transmitting filter is used as a transmitting terminal, said resonator electrodes for said receiving filter are disposed in parallel, said capacitor electrodes for said receiving filter are disposed so that parts thereof are laid over both of said resonator electrodes for said receiving filter adjacent to each other, said capacitor electrode for said receiving filter disposed so as to be laid over a part of said resonator electrode for said receiving filter disposed at one end of the arrangement of said plural resonator electrodes for said receiving filter is electrically connected to the other end of said first transmission line, said end surface electrodes connected to said capacitor electrode for said receiving filter disposed so as to be laid over a part of said resonator electrode for said receiving filter disposed at the other end of the arrangement of said plural resonator electrodes for said receiving filter is used as a receiving terminal, a third of said at least four end surface electrodes connected to the other end of said second transmission line electrode is used as an antenna terminal, and said end surface electrodes connected to said first shield electrode, said second shield electrode, said third shield electrode and said fourth shield electrode are grounded.