Abstract: A power amplifier unit includes a power amplifier circuit that amplifies a radio-frequency input signal, a first impedance matching circuit that performs impedance matching for an output signal of the power amplifier circuit, a second-order harmonic termination circuit on an output side of the first impedance matching circuit and that reflects at least part of even-ordered and odd-ordered harmonics contained in a signal input from the first impedance matching circuit to output the at least part of the harmonics from an input terminal as a radio-frequency signal and outputs a radio-frequency signal containing a fundamental and the remainder of the harmonics from an output terminal, and a filter that is on a subsequent stage of the second-order harmonic termination circuit, that attenuates at least part of the even-ordered and odd-ordered harmonics, and that outputs a radio-frequency signal including the fundamental and the remainder of the even-ordered and odd-ordered harmonics.

Abstract: A power amplifier circuit includes a first amplifier that amplifies a first signal, and a second amplifier arranged subsequent to the first amplifier. The second amplifier amplifies a second signal that is based on an output signal of the first amplifier. The first amplifier performs class inverse-F operation, and the second amplifier performs class F operation.

Abstract: A semiconductor device including a radio-frequency amplifier circuit and a band selection switch are mounted on or in a module substrate. An output matching circuit includes at least one passive element disposed on or in the module substrate. The output matching circuit is coupled between the radio-frequency amplifier circuit and the band selection switch. The semiconductor device includes a first member having a semiconductor portion made of an elemental semiconductor and a second member joined to the first member in surface contact with the first member. The radio-frequency amplifier circuit including a semiconductor element made of a compound semiconductor is formed at the second member. The semiconductor device is disposed in close proximity to the output matching circuit in plan view. The output matching circuit is disposed in close proximity to the band selection switch.

Abstract: A radio frequency module includes a module substrate having major surfaces that face each other, a first base part that is at least partially comprised of a first semiconductor material and in which an electronic circuit is formed, a second base part that is at least partially comprised of a second semiconductor material different from the first semiconductor material and in which a power amplifier is formed, and a switch connected to an output terminal of the power amplifier. The first base part is disposed on or over the major surface; the second base part is disposed between the module substrate and the first base part, is joined to the first base part, and is connected to the major surface via an electrode; and the switch is disposed on or over the major surface.

Abstract: A radio frequency module includes: a module board that includes a first principal surface and a second principal surface on opposite sides of the module board; a power amplifier; and a first circuit component. The power amplifier includes: a first amplifying circuit element; a second amplifying circuit element; and an output transformer that includes a primary coil and a secondary coil. An end of the primary coil is connected to an output terminal of the first amplifying circuit element. Another end of the primary coil is connected to an output terminal of the second amplifying circuit element. An end of the secondary coil is connected to an output terminal of the power amplifier. The first amplifying circuit element and the second amplifying circuit element are disposed on the first principal surface. The first circuit component is disposed on the second principal surface.

Abstract: An integrated circuit includes a first base that has at least a part formed of a first semiconductor material and that includes an electric circuit, a second base that has at least a part formed of a second semiconductor material having a thermal conductivity lower than the first semiconductor material and that includes a power amplifier circuit, and a high thermal conductive member that has at least a part formed of a high thermal conductive material having a thermal conductivity higher than the first semiconductor material and that is disposed between the electric circuit and the power amplifier circuit. At least a part of the high thermal conductive member overlaps at least a part of the first base and at least a part of the second base in plan view. The high thermal conductive member is in contact with the first base and the second base.

Abstract: A radio-frequency module includes a first base made of a first semiconductor material; a second base that is made of a second semiconductor material having a thermal conductivity lower than that of the first semiconductor material and which includes a power amplifier circuit; a third base including a transmission filter circuit; and a module substrate having a main surface on which the first base, the second base, and the third base are arranged. The first base is joined to the main surface via an electrode. The second base is arranged between the module substrate and the first base in a sectional view and is joined to the main surface via an electrode. At least part of the first base is overlapped with at least part of the second base and at least part of the third base in a plan view.

Abstract: A power amplifier circuit includes a first transistor having a first terminal to which a voltage corresponding to a variable power supply voltage is to be supplied and a second terminal to which a radio-frequency signal is to be supplied, the first transistor being configured to amplify the radio-frequency signal, a bias circuit configured to supply a bias current or voltage to the second terminal of the first transistor, and an adjustment circuit configured to adjust the bias current or voltage in accordance with the variable power supply voltage supplied from a power supply terminal.

Abstract: A radio frequency module includes a module substrate including major surfaces that face each other; a first base part that is at least partially comprised of a first semiconductor material and in which an electronic circuit is formed; a second base part that is at least partially comprised of a second semiconductor material having a thermal conductivity lower than the thermal conductivity of the first semiconductor material and in which an amplifier circuit is formed; and an external connection terminal disposed on or over the major surface. The first base part and the second base part are disposed on or over the major surface out of the major surfaces; and the second base part is disposed between the module substrate and the first base part, is joined to the first base part, and is connected to the major surface via an electrode.

Abstract: A matching circuit includes: a first wire having one end connected to a first terminal and another end; a second wire having one end connected to the other end of the first wire and another end connected to a first reference potential and electromagnetically coupled to the first wire; and a third wire having one end connected to the one end of the second wire and another end connected to a second terminal and electromagnetically coupled to at least one of the first wire and the second wire.

Abstract: A power amplifier unit includes a power amplifier circuit that amplifies a radio-frequency input signal, a first impedance matching circuit that performs impedance matching for an output signal of the power amplifier circuit, a second-order harmonic termination circuit on an output side of the first impedance matching circuit and that reflects at least part of even-ordered and odd-ordered harmonics contained in a signal input from the first impedance matching circuit to output the at least part of the harmonics from an input terminal as a radio-frequency signal and outputs a radio-frequency signal containing a fundamental and the remainder of the harmonics from an output terminal, and a filter that is on a subsequent stage of the second-order harmonic termination circuit, that attenuates at least part of the even-ordered and odd-ordered harmonics, and that outputs a radio-frequency signal including the fundamental and the remainder of the even-ordered and odd-ordered harmonics.

Abstract: A radio frequency module includes: a module board that includes a first principal surface and a second principal surface on opposite sides of the module board; a power amplifier; and a first circuit component. The power amplifier includes: a first amplifying circuit element; a second amplifying circuit element; and an output transformer that includes a primary coil and a secondary coil. An end of the primary coil is connected to an output terminal of the first amplifying circuit element. Another end of the primary coil is connected to an output terminal of the second amplifying circuit element. An end of the secondary coil is connected to an output terminal of the power amplifier. The first amplifying circuit element and the second amplifying circuit element are disposed on the first principal surface. The first circuit component is disposed on the second principal surface.

Abstract: A power amplifier module includes a first transistor that amplifies and outputs a signal, a second transistor that supplies a bias current to a base of the first transistor, and a ballast resistor circuit that is disposed between the base and an emitter of the second transistor and that includes first and second resistive elements and a switching element. The first resistive element is arranged in series on a line connecting the base and the emitter. The first and second resistive elements are series-connected or parallel-connected. When the second resistive element is series-connected to the first transistor, the switching element is parallel-connected to the second resistive element. When the second resistive element is parallel-connected to the first transistor, the switching element is series-connected to the second resistive element. The switching element is switched on/off based on a collector current of the second transistor.

Abstract: A radio frequency module includes: a module board that includes a first principal surface and a second principal surface on opposite sides of the module board; a power amplifier; and a first circuit component. The power amplifier includes: a first amplifying circuit element; a second amplifying circuit element; and an output transformer that includes a primary coil and a secondary coil. An end of the primary coil is connected to an output terminal of the first amplifying circuit element. Another end of the primary coil is connected to an output terminal of the second amplifying circuit element. An end of the secondary coil is connected to an output terminal of the power amplifier. The first amplifying circuit element and the second amplifying circuit element are disposed on the first principal surface. The first circuit component is disposed on the second principal surface.

Abstract: A power amplifier circuit includes a transistor having a base to which a radio frequency signal is input and a collector to which a power supply voltage that varies in accordance with an envelope of amplitude of the radio frequency signal is supplied and from which an amplified signal obtained by amplifying the radio frequency signal is output; a first termination circuit provided at a stage subsequent to the transistor and configured to attenuate a harmonic component of the amplified signal; and a second termination circuit provided at the stage subsequent to the transistor and configured to attenuate a harmonic component of the amplified signal. The first termination circuit and the second termination circuit have a property of resonating for a radio frequency signal having a frequency between a frequency of a second harmonic component and a frequency of a third harmonic component.

Abstract: A power amplifier circuit includes a first amplifier that amplifies a first signal, and a second amplifier arranged subsequent to the first amplifier. The second amplifier amplifies a second signal that is based on an output signal of the first amplifier. The first amplifier performs class inverse-F operation, and the second amplifier performs class F operation.

Abstract: A power amplifier circuit includes a first amplifier that amplifies a first signal, and a second amplifier arranged subsequent to the first amplifier. The second amplifier amplifies a second signal that is based on an output signal of the first amplifier. The first amplifier performs class inverse-F operation, and the second amplifier performs class F operation.

Abstract: A power amplification device includes a first member in which a first circuit is formed, a second member in which a second circuit is formed, and a member-member connection conductor that electrically connects the first circuit and the second circuit to each other. The second member is mounted on the first member. The second circuit includes a first amplifier, which amplifies a radio frequency signal to output a first amplified signal. The first circuit includes a control circuit that controls an operation of the second circuit. At least part of a first termination circuit, which is connected to the first amplifier through the member-member connection conductor and which attenuates a harmonic wave component of the first amplified signal, is formed in the first member.

Abstract: A second member is joined in surface contact with a first surface of a first member including a semiconductor region made from an elemental semiconductor. The second member includes a radio-frequency amplifier circuit made from a compound semiconductor. A conductive protrusion projects from the second member toward a side opposite to the first member. The first member includes a temperature measurement element that detects a temperature.

Abstract: A semiconductor device including a radio-frequency amplifier circuit and a band selection switch is mounted on or in a module substrate. An output matching circuit coupled between the radio-frequency amplifier circuit and the band selection switch is on or in the module substrate. The semiconductor device includes a first member at which the band selection switch having a semiconductor element made of an elemental semiconductor is formed and a second member joined to the first member in surface contact therewith. The radio-frequency amplifier circuit including a semiconductor element made of a compound semiconductor is formed at the second member. Conductive protrusions are raised from first and second members. The semiconductor device is mounted on or in the module substrate with the conductive protrusions interposed therebetween, and in plan view, is in close proximity to the output matching circuit or overlaps a passive element constituting the output matching circuit.