Filter

• US 6,621,378 B2
• Filed: 06/12/2001
• Issued: 09/16/2003
• Est. Priority Date: 06/15/2000
• 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: Naruse, Takumi, Sakita, Hiromi, Kiyosue, Kuniaki, Eguchi, Kazuhiro, Sasaki, Katsumi, Isozaki, Kenzo
• Primary Examiner(s): Ham, Seungsook
• Application Number:
  US09/879,018
• Publication Number:
  US 20020021191A1
• Time in Patent Office: 826 Days
• Field of Search: 333/185, 333/186, 333/175, 333/12, 333/181, 336/200
• US Class Current: 333/185
• CPC Class Codes: H03H 2001/0085 Multilayer, e.g. LTCC, HTCC, green sheets
• CPC Class Codes: H03H 7/0115 comprising only inductors and capacitors H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence
• CPC Class Codes: H03H 7/1766 Parallel LC in series path H03H7/1783 takes precedence

Abstract

A filter includes a substrate with a relative dielectric constant of 200 or less and a thickness of 0.1 mm or more. A first electrode is disposed on at least one surface of the substrate, a group of second electrodes is disposed on at least the other surface of the substrate. Each of the second electrodes is not in contact with each other and is not in contact with the first electrode. The filter also includes a chip type inductance element. The chip type inductance element has an inductance ranging from 0.1 nH to 30 nH and has dimensions of L1 in length, L2 in width and L3 in height, which satisfy the following conditions;

0.3 mm<L1<2.1 mm

0.1 mm<L2<1.1 mm

0.1 mm<L3<1.1 mm.

Claims

1. A filter comprising:

a substrate with a dielectric constant of 200 or less, said substrate having a first surface, a second surface, and a side surface between said first and said second surfaces;

a first electrode disposed on at least said first surface;

a group of second electrodes disposed on at least said second surface, each of said second electrodes not in contact with each other and not in contact with said first electrode, and a portion of said group of second electrodes being located directly opposite a portion of said first electrode via said substrate to form at least one capacitance; and

a plurality of inductance elements, each of said inductance elements having terminals, each of said terminals connected to at least two electrodes selected from said group of second electrodes and said inductance elements having an inductance ranging from 0.1 nH to 30 nH and dimensions L1 in length, L2 in width and L3 in height, said dimensions satisfying conditions as follows;

2. The filter of claim 1, wherein said first electrode is a grounding electrode and at least two electrodes of said group of second electrodes are input and output terminals.

3. The filter of claim 1, wherein at least one of said plurality of inductance elements has a Q factor of 20 or more at a frequency exceeding 1 GHz.

4. The filter of claim 1, wherein said dimensions of at least one inductance element of said plurality of inductance elements being different from said dimensions of another inductance element.

5. The filter of claim 1, wherein at least one element of said plurality of inductance elements includes a conductive film having a spiral groove therein and a protective material on said conductive film.

6. The filter of claim 1, wherein at least one element of said plurality of inductance elements having terminals, a base between said terminals, and a wire wound around said base, said wire having ends which are joined respectively to said terminals.

7. The filter of claim 1, wherein a chip type capacitor is connected in parallel with at least one element of said plurality of inductance elements.

8. The filter of claim 1, further comprising a recess on a surface of said substrate, at least one part of at least one element of said plurality of inductance elements being disposed in said recess.

9. The filter of claim 1, further comprising a protective material provided on a surface of said substrate, on which at least one element of said plurality of inductance elements is disposed.

10. The filter of claim 1, wherein said first electrode and said group of said second electrodes are formed of at least one selected from a group of silver, copper, a silver alloy, and a copper alloy.

11. The filter of claim 1, wherein said substrate is made of a ceramic material.

12. The filter of claim 4, wherein said plurality of inductance elements each have center lines, said center lines of at least two inductance elements of said plurality of inductance elements are aligned in a same direction.

13. The filter of claim 4, wherein:

one terminal of a first inductance element and one terminal of a second inductance element are connected to one electrode selected from said group of second electrodes; and

another terminal of said first inductance element and another terminal of said second inductance element are connected respectively to two electrodes selected from said group of second electrodes.

14. The filter according to claim 1, wherein said substrate has a thickness of 0.1 mm or more.

15. The filter according to claim 1, wherein at least one element of said plurality of inductance elements is a trimming type inductance element, a plating type inductance element, a wire winding type inductance element, or a buried type inductance element.

16. The filter according to claim 1, wherein a capacitor or an inductor is incorporated in the substrate.