Multilayer filter

Patent metadata

Field	Value
Publication number	US-2021257984-A1
Application number	US-202117176607-A
Country	US
Kind code	A1
Filing date	Feb 16, 2021
Priority date	Feb 17, 2020
Publication date	Aug 19, 2021
Grant date	—

Abstract

In a multilayer filter, a first LC parallel resonance unit, a second LC parallel resonance unit, and an LC circuit unit are configured in an element body, in which the LC circuit unit is connected between the first LC parallel resonance unit and the second LC parallel resonance unit in a path between a first terminal electrode and a second terminal electrode, a conductor pattern constituting an inductor of the LC circuit unit is not disposed between a conductor pattern constituting a first inductor of the first LC parallel resonance unit and a conductor pattern constituting a second inductor of the second LC parallel resonance unit in the element body, and the first inductor of the first LC parallel resonance unit and the second inductor of the second LC parallel resonance unit are magnetically coupled.

First claim

What is claimed is:

1 . A multilayer filter comprising:
an element body formed by laminating a plurality of insulator layers; and a first terminal and a second terminal disposed on an outer surface of the element body, wherein the inside of the element body is configured by: a first LC parallel resonance unit configured by a first inductor and a first capacitor connected in parallel; a second LC parallel resonance unit configured by a second inductor and a second capacitor connected in parallel; and an LC circuit unit configured to include an inductor and a capacitor, the LC circuit unit is connected between the first LC parallel resonance unit and the second LC parallel resonance unit in a path between the first terminal and the second terminal, a conductor pattern constituting the inductor of the LC circuit unit is not disposed between a conductor pattern constituting the first inductor of the first LC parallel resonance unit and a conductor pattern constituting the second inductor of the second LC parallel resonance unit in the element body, and the first inductor of the first LC parallel resonance unit and the second inductor of the second LC parallel resonance unit are magnetically coupled.

2 . The multilayer filter according to claim 1 , wherein the LC circuit unit is configured to include:
a first LC series resonance unit configured by a third inductor and a third capacitor connected in series, and a second LC series resonance unit configured by a fourth inductor and a fourth capacitor connected in series, and the first LC series resonance unit and the second LC series resonance unit are disposed at positions sandwiching the first LC parallel resonance unit and the second LC parallel resonance unit therebetween and disposed to be spaced apart on outer sides of the first LC parallel resonance unit and the second LC parallel resonance unit.

3 . The multilayer filter according to claim 2 , wherein the first inductor, the second inductor, the third inductor, and the fourth inductor are each configured by a conductor pattern and a through-hole conductor.

4 . The multilayer filter according to claim 1 , which is a multiplexer including a bandpass filter configured to have the first LC parallel resonance unit, the second LC parallel resonance unit, and the LC circuit unit.

Assignees

• Tdk Corp

Inventors

• Sato Takuya
• Tsukamoto Kazuhiro

Classifications

• H03H7/1766

  Parallel LC in series path (H03H7/1783 takes precedence) · CPC title

• H03H7/09

  Filters comprising mutual inductance · CPC title

• H03H7/12 Primary

  Bandpass or bandstop filters with adjustable bandwidth and fixed centre frequency (H03H7/09 takes precedence) · CPC title

• H03H7/01

  Frequency selective two-port networks · CPC title

• H03H7/1708

  Comprising bridging elements, i.e. elements in a series path without own reference to ground and spanning branching nodes of another series path (H03H7/07 takes precedence) · CPC title