公开(公告)号：US20190036508A1

公开(公告)日：2019-01-31

申请号：US16145438

申请日：2018-09-28

Applicant: Murata Manufacturing Co., Ltd.

Inventor： Hideki TSUKAMOTO ,  Masakazu TANI ,  Kei MATSUTANI

IPC: H03H7/46 ,  H03H7/075 ,  H03H7/24 ,  H03H7/38 ,  H03H9/54 ,  H03F3/19 ,  H04B1/10 ,  H04B1/04

CPC classification number: H03H7/465 ,  H03F3/19 ,  H03F3/195 ,  H03F2200/451 ,  H03H7/075 ,  H03H7/24 ,  H03H7/38 ,  H03H7/461 ,  H03H9/54 ,  H03H9/542 ,  H03H9/568 ,  H03H9/605 ,  H03H9/6436 ,  H03H9/6483 ,  H03H2210/012 ,  H03H2210/036 ,  H04B1/0475 ,  H04B1/1018

Abstract: A first attenuation circuit is connected between a node and ground, and the node is located between a ladder resonance circuit and a transmitter-side terminal. A second attenuation circuit is connected between a first parallel arm resonator of the ladder resonance circuit and ground and is connected in series to the first parallel arm resonator. The first attenuation circuit includes a second parallel arm resonator and a first switch that switches between a first state in which the second parallel arm resonator is connected to the node and a second state in which the first switch is open. The second attenuation circuit includes a capacitor and a second switch that switches between a first state in which the capacitor is connected to the first parallel arm resonator and a second state in which the first parallel arm resonator is connected to ground.

公开(公告)号：US20250023586A1

公开(公告)日：2025-01-16

申请号：US18896950

申请日：2024-09-26

Applicant: Murata Manufacturing Co., Ltd.

Inventor： Motoji TSUDA ,  Kei MATSUTANI ,  Kanta MOTOKI ,  Reiji NAKAJIMA ,  Yuji TAKEMATSU

IPC: H04B1/00 ,  H04B1/44 ,  H04L5/14

Abstract: A radio frequency circuit includes an antenna connection terminal, an input terminal, an output terminal, a filter having a pass band including at least part of a transmission band of Band A for FDD, a filter having a pass band including at least part of a reception band of the Band A, and a switch that includes terminals. The antenna connection terminal is connected to the terminal. The filter is connected between the terminal and the input terminal. The filter is connected between the terminal and the output terminal. The switch is configured to switch between first connection, second connection, and third connection. In the first connection, the terminal is connected to the terminal and the terminal is not connected to the terminal. In the second connection, the terminal is connected to the terminal and the terminal is not connected to the terminal.

公开(公告)号：US20190214968A1

公开(公告)日：2019-07-11

申请号：US16353037

申请日：2019-03-14

Applicant: Murata Manufacturing Co., Ltd.

Inventor： Kei MATSUTANI ,  Koji NOSAKA

IPC: H03H9/64 ,  H03F3/189 ,  H04B1/40

Abstract: A radio frequency front-end circuit includes a frequency variable filter connected to a select terminal of a switching circuit, and a filter connected to a select terminal of the switching circuit, the switching circuit including a switch that switches over conduction and non-conduction between a common terminal and the select terminal, the filter including a serial arm resonance circuit connected to the select terminal, a parallel arm resonator, and a frequency varying circuit that is a circuit including a capacitor and a switch connected in parallel to each other, and that is connected in series to the parallel arm resonator, wherein the frequency varying circuit shifts a frequency of the filter depending on conduction and non-conduction of the switch, and an on-resistance of the switch is smaller than an on-resistance of the switch.