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US 10,873,309 B2Granted
LC filter, radio-frequency front-end circuit, and communication device
AssigneeMurata Manufacturing Co., Ltd.
InventorHirotsugu Mori
Life of this patent
Estimating the term…
Abstract
A variable-frequency LC filter (1A) includes a multilayer circuit board, a series arm capacitor (11) formed in the multilayer circuit board and disposed in a series arm path that connects an input electrode to an output electrode, and a parallel arm inductor (21) formed in the multilayer circuit board and disposed in a parallel arm path that connects a ground electrode to a node (N1) in the series arm path. When the multilayer circuit board is viewed in plan, of the series arm capacitor (11) and the parallel arm inductor (21), only the parallel arm inductor (21) overlaps with the ground electrode.
Claims12
An inductive-capacitive (LC) filter comprising:
- a multilayer circuit board;
- an input electrode to which a radio-frequency signal is inputted;
- an output electrode from which a radio-frequency signal is outputted;
- a ground electrode constituted by one or more layers of the multilayer circuit board;
- a first series arm capacitor provided in the multilayer circuit board and disposed in a series arm path connecting the input electrode to the output electrode;
- and
- a first parallel arm inductor provided in the multilayer circuit board and disposed in a parallel arm path connecting the ground electrode to a first node on the series arm path, wherein
- in a plan view of the multilayer circuit board, the first parallel arm inductor overlaps the ground electrode and the input electrode, the output electrode, and the first series arm capacitor do not overlap the ground electrode,
- wherein:
- the multilayer circuit board comprises a ground electrode layer,
- the ground electrode layer comprises a ground electrode formation region and a ground electrode opening region,
- the ground electrode is provided in the ground formation region and is not provided in the ground electrode opening region,
- in a plan view of the ground electrode layer, the ground electrode opening region is surrounded by the ground electrode formation region in the plan view, and
- in the plan view of the ground electrode layer, the first series arm capacitor is contained in the ground electrode opening region, and the first parallel arm inductor is contained in the ground electrode formation region.
11 more elements
An inductive-capacitive (LC) filter comprising,
- a multilayer circuit board;
- an input electrode to which a radio-frequency signal is inputted;
- an output electrode from which a radio-frequency signal is outputted;
- a ground electrode constituted by one or more layers of the multilayer circuit board;
- a first series arm capacitor provided in the multilayer circuit board and disposed in a series arm path connecting the input electrode to the output electrode;
- a first parallel arm inductor provided in the multilayer circuit board and disposed in a parallel arm path connecting the ground electrode to a first node on the series arm path, wherein
- in a plan view of the multilayer circuit board, the first parallel arm inductor overlaps the ground electrode and the input electrode, the output electrode, and the first series arm capacitor do not overlap the ground electrode;
- and
- a first variable capacitor disposed in the parallel arm path that connects the first node to the ground electrode, a capacitance value of the first variable capacitor being adjustable,
- wherein the first parallel arm inductor and the first variable capacitor are connected in series with each other.
7 more elements
An inductive-capacitive (LC) filter comprising:
- a multilayer circuit board;
- an input electrode to which a radio-frequency signal is inputted;
- an output electrode from which a radio-frequency signal is outputted;
- a ground electrode constituted by two or more layers of the multilayer circuit board;
- a first series arm capacitor provided in the multilayer circuit board and disposed in a series arm path connecting the input electrode to the output electrode;
- and
- a first parallel arm inductor provided in the multilayer circuit board and disposed in a parallel arm path connecting the ground electrode to a first node on the series arm path, wherein
- in a plan view of the multilayer circuit board, the first parallel arm inductor overlaps the ground electrode and the input electrode, the output electrode, and the first series arm capacitor do not overlap any part of the ground electrode.
5 more elements
Dependencies are inferred from the claim text.