Murata Manufacturing Co., Ltd.

Masamichi Tokuda

Makoto Tabei

Daisuke Watanabe

Ken Wakaki

Takayuki Kawano

Kazuaki Deguchi

Keiichi Honda

Tsutomu Oonaro

An amplifier device includes an amplifier including cascade-connected power amplifiers in a plurality of stages and a bias circuit configured to supply bias currents to the amplifier. A bias current supplied to a power amplifier in the first stage of the power amplifiers in the plurality of stages exhibits a positive temperature characteristic. A bias current supplied to a power amplifier in the final stage exhibits a negative temperature characteristic.

Amplifier device

A temperature detection circuit includes a first temperature sensor unit that includes a temperature sensor configured to detect a temperature of a target object and that is configured to output a first analog signal indicating the detected temperature, a second temperature sensor unit that includes a temperature sensor configured to detect a temperature of the target object and that is configured to output a second analog signal indicating the detected temperature, and an AD converter configured to convert the second analog signal into a digital signal and configured to output the digital signal.

Temperature detection circuit and module

A high-frequency circuit includes an amplifier, a power distributor disposed on an output route of the amplifier, a first by-pass route that bypasses the amplifier, a second by-pass route that bypasses the power distributor, a first switch and a second switch disposed in series on the first by-pass route, and a third switch disposed in series on the second by-pass route. The first by-pass route is connected to a first node on a route connecting a signal input terminal and the amplifier and a second node on a route connecting the amplifier and the power distributor. The second by-pass route is connected to a third node between the first switch and the second switch and a fourth node on an output route of the power distributor.

High-frequency circuit

Provided is an amplification circuit that includes: a low-noise amplifier that includes an FET as an amplification element and that amplifies a radio-frequency signal inputted to the gate of the FET; an input matching network that matches the input impedance of the low-noise amplifier; and a switch that is serially connected between ground and a node on a line connecting the input matching network and the gate of the FET to each other.

Amplification circuit and communication device

A radio-frequency circuit includes: an amplifier; a matching circuit connected to an output side of the amplifier; and a power splitter connected to an output side of the matching circuit. The power splitter includes a differential inductor and a resistor element. The differential inductor includes an input node (ni), a first line, and a second line. The input node (ni) is connected to the matching circuit. The first line and the second line are respectively wound into coil form and connected to the input node (ni). The resistor element forms a connection between a node (n) on an output side of the first line and a node (n) on an output side of the second line. The first line and the second line are wound in opposite directions and have the same coil axis.

Radio-frequency circuit

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

An amplification circuit includes: an amplifier including a transistor that is connected between an input terminal and an output terminal; an input matching network that is connected between the input terminal and an input side of the amplifier and converts an impedance from a low impedance to a high impedance; a limiter circuit that is connected between a node between the input matching network and the input side of the amplifier, and ground and includes two diodes connected in opposite directions to each other; and a capacitor that is connected in series with the limiter circuit between the node and ground.

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

A voltage supply circuit includes a level shifter that switches between voltages of two voltage input units and that outputs one of the voltages, a charge pump that transforms a voltage of an input power supply and that applies the transformed voltage to the level shifter, and a charge pump control circuit. The voltage supply circuit controls supply and interruption of a predetermined voltage to a voltage-supplied circuit (RF switch). The charge pump control circuit causes the charge pump to perform a continuous operation in an on-mode and to perform an intermittent operation in an off-mode, the off-mode representing a state in which the voltage supply to the voltage-supplied circuit (RF switch) is stopped, the on-mode representing a state in which the predetermined voltage is supplied.

Voltage supply circuit and radio-frequency circuit module

A level conversion circuit () includes an EFET (), a diode () and resistors (). The drain of the EFET () is connected to an output terminal of the level conversion circuit (). The drain and the gate of the EFET () are in conductive contact with each other. The source of the EFET () is grounded via the resistor (). The drain of the EFET () is connected to one end of the resistor (). The other end of the resistor () is connected to the cathode of the diode (). The anode of the diode () is connected to a control voltage input terminal.

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Kyoto, Japan

Masamichi Tokuda