Abstract: Size reduction is enabled. A power amplifying circuit includes a splitter, a first amplifier, a second amplifier, and a third amplifier. The splitter splits an input signal into a first signal and a second signal. The first amplifier has a first input terminal and a first output terminal, amplifies the first signal, and outputs a first amplified signal. The second amplifier has a second input terminal and a second output terminal, amplifies the second signal, and outputs a second amplified signal. The third amplifier has a third input terminal and a third output terminal, amplifies the first signal, and outputs a third amplified signal. The first output terminal and the second output terminal are connected to each other, the third input terminal is connected to the first input terminal, and the third output terminal is connected to the second output terminal.

Abstract: A current flowing through a transistor of a final-stage amplifier is suppressed. A power amplification circuit includes a driving-stage amplifier, a final-stage amplifier, a power supply terminal, a first voltage control circuit, and a second voltage control circuit. The driving-stage amplifier includes a first transistor having a first input terminal, a first output terminal, and a first ground terminal. The final-stage amplifier includes a second transistor having a second input terminal, a second output terminal, and a second ground terminal. The first voltage control circuit is connected between the power supply terminal and the first output terminal, and controls a first power supply voltage applied to the first transistor. The second voltage control circuit is connected between the power supply terminal and the second output terminal, and controls a second power supply voltage applied to the second transistor.

Abstract: An amplifier transistor operates in two operation modes having different characteristics. A first bias circuit including a first bias supply transistor supplies an output current of the first bias supply transistor to the amplifier transistor as a bias current. A second bias circuit including a second bias supply transistor supplies a portion of an output current of the second bias supply transistor to the amplifier transistor as a bias current. At least one of the first bias circuit and the second bias circuit is selected and operates in accordance with an operation mode of the amplifier transistor by using a bias control signal input to a bias control terminal. The second bias circuit includes a current path along which a portion of the output current of the second bias supply transistor is returned to the second bias circuit.

Abstract: A power amplifier circuit includes a first path and a second path between an input terminal and an output terminal, a first amplifier located in the first path operative in a first mode, a second amplifier located in the second path operative in a second mode, a first matching circuit between the first amplifier and the output terminal in the first path, a first capacitor having a first end connected to the output terminal side of the first matching circuit, and a second end, a first inductor having a first end connected to the second end of the first capacitor and a second end grounded, and a short-circuit switch connected in parallel with the first inductor. The short-circuit switch short-circuits the first and second ends of the first inductor in the first mode and is placed in an open-circuit position in the second mode.

Abstract: A power amplifier includes an amplifier circuit group including multiple amplifier circuits, a distributing circuit that distributes an input signal to each of the multiple amplifier circuits, and a combining circuit that combines output signals from the multiple amplifier circuits. Each of the multiple amplifier circuits includes an amplifier transistor including multiple cell transistors having different sizes and bias circuits that supply bias current to the respective cell transistors.

Abstract: A power amplifier module includes a first amplifier, a power splitter, a second amplifier, a third amplifier, a phase shifter, a combining unit, and a controller. The first amplifier amplifies a first signal and outputs a second signal. The power splitter splits the second signal into a third signal and a fourth signal. The second amplifier amplifies the third signal and outputs a fifth signal. The third amplifier amplifies the fourth signal and outputs a sixth signal. The phase shifter receives the fifth signal and shifts a phase of the fifth signal. The combining unit combines the fifth signal having the phase shifted by the phase shifter and the sixth signal and outputs an amplified signal of the second signal. The controller outputs a first control signal for controlling a power level of the sixth signal output from the third amplifier.

Abstract: A power amplifying module includes a first input terminal, a second input terminal, a first power amplifier, a stage matching circuit, a bypass line, and a second power amplifier. The first input terminal receives a first input signal in a first operation mode. The second input terminal receives a second input signal in a second operation mode which is different from the first operation mode. The first power amplifier amplifies the first input signal and outputs a first amplified signal. The stage matching circuit is disposed downstream of the first power amplifier and receives the first amplified signal. The bypass line outputs the second input signal to the inside of the stage matching circuit not through the first power amplifier. The second power amplifier is disposed downstream of the stage matching circuit, and amplifies the first amplified signal or the second input signal and outputs a second amplified signal.

Abstract: An amplifier transistor operates in two operation modes having different characteristics. A first bias circuit including a first bias supply transistor supplies an output current of the first bias supply transistor to the amplifier transistor as a bias current. A second bias circuit including a second bias supply transistor supplies a portion of an output current of the second bias supply transistor to the amplifier transistor as a bias current. At least one of the first bias circuit and the second bias circuit is selected and operates in accordance with an operation mode of the amplifier transistor by using a bias control signal input to a bias control terminal. The second bias circuit includes a current path along which a portion of the output current of the second bias supply transistor is returned to the second bias circuit.

Abstract: A high frequency module includes a transmission power amplifier, a bump electrode connected to the transmission power amplifier, and a mounting board on which the transmission power amplifier is mounted, wherein the mounting board includes a via conductor having an elongated shape in the plan view of the mounting board, a board main part placed outside the via conductor, and an insulating part placed inside the via conductor, and the bump electrode and the via conductor are connected while at least partially overlapping each other in the foregoing plan view, and the board main part and the insulating part are each composed of an insulating material of the same kind.

Abstract: A radio-frequency module includes: a transmission power amplifier that includes first and second amplification transistors that are cascade connected to each other; and a mounting substrate that has first and second main surface that face each other, the transmission power amplifier being mounted on the first main surface. The first amplification transistor is arranged in a final stage and has a first emitter terminal. The second amplification transistor is arranged in a stage preceding the first amplification transistor and has a second emitter terminal. The mounting substrate has first to fourth ground electrode layers in order of proximity to the first main surface. The first emitter terminal and the second emitter terminal are not electrically connected to each other via an electrode on the first main surface and are not electrically connected to each other via the first ground electrode layer.

Abstract: A high frequency module includes a transmission power amplifier, a bump electrode connected to a principal surface of the transmission power amplifier and having an elongated shape in a plan view of the principal surface, and a mounting board on which the transmission power amplifier is mounted, wherein the mounting board includes a via conductor having an elongated shape in the plan view, the length direction of the bump electrode and the length direction of the via conductor are aligned in the plan view, and the bump electrode and the via conductor are connected in an overlapping area where the bump electrode and the via conductor overlap at least partially in the plan view, and the overlapping area is an area elongated in the length direction.

Abstract: A power amplifier circuit includes a first path and a second path between an input terminal and an output terminal, a first amplifier located in the first path operative in a first mode, a second amplifier located in the second path operative in a second mode, a first matching circuit between the first amplifier and the output terminal in the first path, a first capacitor having a first end connected to the output terminal side of the first matching circuit, and a second end, a first inductor having a first end connected to the second end of the first capacitor and a second end grounded, and a short-circuit switch connected in parallel with the first inductor. The short-circuit switch short-circuits the first and second ends of the first inductor in the first mode and is placed in an open-circuit position in the second mode.

Abstract: A power amplification circuit includes an amplification transistor, a variable voltage power supply that supplies a variable voltage to a collector of the amplification transistor, a bias circuit that has a constant current amplification transistor outputting a DC bias current to a base of the amplifier transistor, and a current limiting circuit that limits the DC bias current. The current limiting circuit includes a current limiting transistor, a resistor element connected to a collector of the current limiting transistor and the variable voltage power supply, and a resistor element connected to a base of the current limiting transistor and a base of the constant current amplifying transistor.

Abstract: A power amplifier includes an amplifier circuit group including multiple amplifier circuits, a distributing circuit that distributes an input signal to each of the multiple amplifier circuits, and a combining circuit that combines output signals from the multiple amplifier circuits. Each of the multiple amplifier circuits includes an amplifier transistor including multiple cell transistors having different sizes and bias circuits that supply bias current to the respective cell transistors.

Abstract: A radio-frequency module includes: a transmission power amplifier that includes first and second amplification transistors that are cascade connected to each other; and a mounting substrate that has first and second main surface that face each other, the transmission power amplifier being mounted on the first main surface. The first amplification transistor is arranged in a final stage and has a first emitter terminal. The second amplification transistor is arranged in a stage preceding the first amplification transistor and has a second emitter terminal. The mounting substrate has first to fourth ground electrode layers in order of proximity to the first main surface. The first emitter terminal and the second emitter terminal are not electrically connected to each other via an electrode on the first main surface and are not electrically connected to each other via the first ground electrode layer.

Abstract: A high frequency module includes a transmission power amplifier, a bump electrode connected to a principal surface of the transmission power amplifier and having an elongated shape in a plan view of the principal surface, and a mounting board on which the transmission power amplifier is mounted, wherein the mounting board includes a via conductor having an elongated shape in the plan view, the length direction of the bump electrode and the length direction of the via conductor are aligned in the plan view, and the bump electrode and the via conductor are connected in an overlapping area where the bump electrode and the via conductor overlap at least partially in the plan view, and the overlapping area is an area elongated in the length direction.

Abstract: A high frequency module includes a transmission power amplifier, a bump electrode connected to the transmission power amplifier, and a mounting board on which the transmission power amplifier is mounted, wherein the mounting board includes a via conductor having an elongated shape in the plan view of the mounting board, a board main part placed outside the via conductor, and an insulating part placed inside the via conductor, and the bump electrode and the via conductor are connected while at least partially overlapping each other in the foregoing plan view, and the board main part and the insulating part are each composed of an insulating material of the same kind.

Abstract: A power amplification circuit includes an amplification transistor, a variable voltage power supply that supplies a variable voltage to a collector of the amplification transistor, a bias circuit that has a constant current amplification transistor outputting a DC bias current to a base of the amplifier transistor, and a current limiting circuit that limits the DC bias current. The current limiting circuit includes a current limiting transistor, a resistor element connected to a collector of the current limiting transistor and the variable voltage power supply, and a resistor element connected to a base of the current limiting transistor and a base of the constant current amplifying transistor.