Electronic circuit

• US 8,519,805 B2
• Filed: 10/28/2011
• Issued: 08/27/2013
• Est. Priority Date: 10/29/2010
• Status: Active Grant

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Baba, Osamu
• Primary Examiner(s): JONES, STEPHEN E
• Application Number:
  US13/283,979
• Publication Number:
  US 20120105169A1
• Time in Patent Office: 669 Days
• Field of Search: 333/32, 333/33, 333/34, 333/35, 333/238, 333/246
• US Class Current: 333/33
• CPC Class Codes: H01P 1/2039 Galvanic coupling between Input/Output
• CPC Class Codes: H03F 2200/423 Amplifier output adaptation especially for transmission line coupling purposes, e.g. impedance adaptation
• CPC Class Codes: H03F 3/601 using FET's, e.g. GaAs FET's H03F3/607, H03F3/608 take precedence

Abstract

An electronic circuit includes a first transmission line connected to a DC power source, a second transmission line having one end connected to the first transmission line at a connecting node, a narrow portion formed in the second transmission line and provided at a position that is away from a specific position by equal to or greater than ⅛ wavelength of a signal, the specific position being away from the connecting node at a distance equal to ¼ wavelength, and a capacitor having one end connected to the other end of the second transmission line and the other end connected to a reference potential.

Claims

1. An electronic circuit comprising:

a first transmission line connected to a DC power source;

a second transmission line having one end connected to the first transmission line at a connecting node;

a narrow portion formed in the second transmission line and provided at a position that is away from a specific position by equal to or greater than ⅛

wavelength of a signal, the specific position being away from the connecting node at a distance equal to ¼

wavelength; and

a capacitor having one end connected to the other end of the second transmission line and the other end connected to a reference potential.

2. The electronic circuit according to claim 1, wherein the signal is transmitted through the first transmission line.

3. The electronic circuit according to claim 1, wherein the first transmission line and the second transmission line form a T circuit.

4. The electronic circuit according to claim 1, wherein the narrowed portion contacts the first transmission line.

5. The electronic circuit according to claim 1, wherein the narrowed portion is provided away from the first transmission line.

6. The electronic circuit according to claim 1, wherein the reference potential is a ground potential.

7. The electronic circuit according to claim 1, wherein the capacitor is an MIM capacitor.

8. The electronic circuit according to claim 1, wherein an output terminal of a transistor is connected to the one end of the first transmission line.

9. The electronic circuit according to claim 1, wherein the first transmission line, the second transmission line and the capacitor form one of a filter circuit and an impedance matching circuit.