Murata Manufacturing Co., Ltd.

Murata Manufacturingco., Ltd.

Daisuke Watanabe

Takayuki Tomita

Ken Wakaki

Makoto Tabei

Hirofumi Kan

Nobuyasu Negishi

Masamichi Tokuda

Hideyuki Oozu

Asako Sato

Hidenori Suzuki

Nobuyasu Beppu

Yuichi Yoshida

Yukinori Akamoto

Yuuichi Sato

Shunsuke Kimura

Genta Oomichi

Naoki Iwamura

A radio-frequency module includes low-noise amplifiers, switches, filters, and inductors. The switch includes a common terminal and selection terminals. The filter is connected to the selection terminal. Another filter is connected to another selection terminal. The inductor is connected between the common terminal and an input end of the low-noise amplifier. Another inductor is connected between another filter and an input end of the low-noise amplifier. Another switch is connected between a receive path and ground. The receive path links the common terminal and the input end of the low-noise amplifier to each other. Still another switch is connected between a receive path and ground. The receive path links the filter and the input end of the low-noise amplifier to each other. Still another inductor is connected between the receive path and the receive path.

Radio-frequency module and communication apparatus

An amplification circuit includes: a power supply terminal that is connected to a power supply; a transistor that has a source terminal, a drain terminal, and a gate terminal to which a high-frequency signal is input; a transistor that has a source terminal that is connected to the drain terminal, a drain terminal that outputs a high-frequency signal, and a gate terminal that is grounded; a capacitor that is serially disposed on a second path that connects the gate terminal and the power supply terminal to each other; and a switch that is serially disposed on a first path or the second path. The drain terminal and the gate terminal are connected to each other via the switch and the capacitor.

Amplification circuit

An amplification circuit includes: a power supply terminal that is connected to a power supply; a first transistor that has a first source terminal, a first drain terminal, and a first gate terminal to which a high-frequency signal is inputted; a second transistor that has a second source terminal that is connected to the first drain terminal, a second drain terminal that outputs a high frequency signal, and a second gate terminal that is grounded; a capacitor that is serially arranged on a second path that connects the second gate terminal and the power supply terminal; and a switch that is serially arranged on a first path, which connects the second drain terminal and the power supply terminal, or the second path. The second drain terminal and the second gate terminal are connected to each other via the switch and the capacitor.

An amplifier circuit amplifies a radio-frequency signal. The amplifier circuit includes an amplifier, an input matching circuit connected to an input side of the amplifier and matches impedance, and a protection circuit connected to a node in a path within a path between an input matching circuit and the amplifier. The protection circuit includes a first diode connected between the node and a ground, and a second diode connected in parallel with the first diode and connected in a direction opposite to the first diode between the node and the ground. A threshold voltage of each of the first diode and the second diode is greater than a maximum voltage amplitude of the input signal at the node and is less than a difference between a withstand voltage of the amplifier and the bias voltage.

Amplifier circuit

A switch module includes a first terminal, first and second filters, and first and second switches. Impedance of the first filter for a signal in a stop band is capacitive. When the first switch is turned OFF, impedance of the first switch is capacitive, and impedance of the first filter seen from an end portion of the first switch connected to the first filter is not in a short state and impedance of the first filter seen from the first terminal is in an open state.

Switch module

An amplifier circuit () includes a FET () having a source terminal (S), a drain terminal (D), and a gate terminal (G), a FET () having a source terminal (S), a drain terminal (D), and a gate terminal (G) and coupled in parallel with the FET (), a FET () having a source terminal (S) coupled to the drain terminals (Dand D), a drain terminal (D), and a gate terminal (G) and cascoded with the FETs (and), and feedback circuits (and) configured to feed back to the gate terminal (G) a high frequency signal outputted from the source terminal (S) or the drain terminal (D).

An amplification circuit includes a filter circuit, an amplifier, a capacitor, a bypass line, and a switch circuit that includes a first FET and a second FET connected in series between one end and the other end of the bypass line, a first resistance element connected in series to a gate of the first FET, and a second resistance element connected in series to a gate of the second FET. A first control signal is supplied to the gate of the first FET. A second control signal is supplied to the gate of the second FET. A product of a gate length and a gate width of the first FET and a resistance value of the first resistance element is smaller than a product of a gate length and a gate width of the second FET and a resistance value of the second resistance element.

A variable gain circuit includes: input/output terminals Pand Pconfigured to input/output a high frequency signal; a transistor having a signal terminal 'a' connected to the input/output terminal P, a signal terminal 'b' connected to the input/output terminal P, and a control terminal; bias terminals B, Band B, and a reference voltage terminal respectively set to a first variable voltage, a second variable voltage, a third variable voltage, and a fixed voltage that are independent of one another; an impedance element connected between the bias terminal Band the signal terminal a; an impedance element connected between the bias terminal Band the signal terminal b; an impedance element connected between the bias terminal Band the control terminal; and a first switch configured to switch between connecting and not connecting the reference voltage terminal and the control terminal.

Variable gain circuit, high frequency switch, and transistor circuit

A high frequency circuit () includes a first terminal (), a second terminal (), a third terminal (), a first path, a second path, a first matching element () and a first amplifier () both arranged in the first path, a first switch () connected between a reference terminal and a part of the first path, the part spanning between the first matching element and the first amplifier, a second matching element () and a second amplifier () both arranged in the second path, and a second switch () connected between the reference terminal and a part of the second path, the part spanning between the second matching element and the second amplifier.

High frequency circuit, front-end circuit, and communication device

A radio frequency circuit includes a switching circuit, an amplifying circuit, and a potential stabilizing circuit. The switching circuit includes a switch disposed on a path connecting a first terminal, to which a radio-frequency signal is input, to a second terminal, from which the radio-frequency signal is output, a first capacitor disposed between the first terminal and the switch, and a second capacitor disposed between the switch and the second terminal. The amplifying circuit includes an amplifier disposed between the switching circuit and the second terminal, a third capacitor disposed between the switching circuit and the amplifier, and a fourth capacitor disposed between the amplifier and the second terminal. The potential stabilizing circuit is connected to a first node which is located between the switching circuit and the amplifying circuit and which is located on a path connecting the second capacitor to the third capacitor.

Radio frequency circuit, radio-frequency front-end circuit, and communication device

An amplifier according to an embodiment of the present disclosure includes a first transistor and a first matching circuit. The first matching circuit is connected between an input terminal and a control terminal of the first transistor. A first terminal of the first transistor is connected to a ground. A second terminal of the first transistor is connected to a power supply and an output terminal. The first matching circuit includes a first inductor, a second inductor, and a first switch. The first inductor has an end connected to the control terminal. The second inductor has an end connected to the other end of the first inductor. The first switch is configured to selectively switch between electrical continuity between the input terminal and the other end of the first inductor and electrical continuity between the input terminal and the other end of the second inductor.

Amplifier

Provided is an amplification circuit that amplifies an input signal and outputs an amplified signal. The amplification circuit includes: an amplification element that outputs the amplified signal from an output terminal thereof; an inductor having one end to which a power supply voltage is supplied and another end that is connected to the output terminal of the amplification element; a variable resistor that is connected in parallel with the inductor; and a resistance value adjusting circuit that adjusts a resistance value of the variable resistor in accordance with the temperature.

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Kyoto, Japan

Daisuke Watanabe