Abstract: A multiplexer includes: a switch capable of connecting a common terminal to at least one of a first selection terminal, a second selection terminal, and a third selection terminal at the same time; a first filter connected to the first selection terminal, the first filter having a first pass band; a second filter connected to the second selection terminal, the second filter having a second pass band that is different from the first pass band; and a coupling circuit connected to the third selection terminal and the first filter, the coupling circuit forming a signal path between the third selection terminal and the first filter by electromagnetic coupling.

Abstract: The radio frequency module includes a mounting board, a first metal member, and a second metal member. The first metal member and the second metal member are disposed on the mounting board. The first metal member has a longitudinal direction along a first direction in plan view from a thickness direction of the mounting board. The second metal member has a longitudinal direction along a second direction in plan view from the thickness direction of the mounting board. The first or second metal member is placed between a first electronic component and a second electronic component. The first metal member has a first recessed portion. The second metal member has a through hole and a second recessed portion. The through hole passes through the second metal member in the direction intersecting with the second direction. The second recessed portion faces and is in contact with the first recessed portion.

Abstract: To improve isolation among a plurality of electronic components. A radio frequency module includes a mounting substrate, a first electronic component and a second electronic component, a metal member, a first metal layer, a resin layer, and a second metal layer. The metal member is disposed between the first electronic component and the second electronic component on a first main surface of the mounting substrate. The first metal layer is disposed on the first main surface of the mounting substrate. The second metal layer covers at least a part of the resin layer. The first metal layer has a ground potential, and is in contact with the second metal layer. The metal member is in contact with the first metal layer and the second metal layer.

Abstract: A radio frequency module includes a mount board, an acoustic wave filter, a temperature sensor, and a correction circuit. The mount board has a first principal surface and a second principal surface on opposite sides of the mount board. The acoustic wave filter is disposed on the first principal surface side of the mount board. The temperature sensor is disposed on the second principal surface side of the mount board. The correction circuit corrects a pass band of the acoustic wave filter in accordance with a temperature measured by the temperature sensor.

Abstract: A substrate has an upper main surface and a lower main surface arranged in an up-down direction. A metal member includes a plate-shaped portion provided on an upper main surface of a substrate, the plate-shaped portion having a front main surface and a back main surface arranged in a front-back direction when viewed in an up-down direction. The sealing resin layer is provided on the upper main surface of the substrate, covers the metal member, the first electronic component, and the second electronic component, and has an upper surface. The shield is provided on the upper surface of the sealing resin layer so as to be connected to the upper end of the plate-shaped portion. The plate-shaped portion is inclined with respect to the up-down direction such that an upper end of the plate-shaped portion is located in front of a lower end of the plate-shaped portion.

Abstract: A radio-frequency module includes a power amplifier, a power amplifier, a low noise amplifier, a duplexer that has a passband including a communication band A included in a communication band group X and that is connected to the power amplifier and the low noise amplifier, a duplexer that has a passband including a communication band C included in a communication band group Y lower than the communication band group X and that is connected to the power amplifier, and a module substrate having the power amplifier, the power amplifier, the low noise amplifier, and the duplexers arranged thereon. In a plan view of the module substrate, a distance between the power amplifier and the low noise amplifier is longer than a distance between the power amplifier and the low noise amplifier.

Abstract: A radio-frequency circuit is provided that includes a power amplifier, a control circuit, an on-off switch, a connection terminal, and a mount board. The power amplifier supports an APT system and an ET system. The control circuit controls the power amplifier by using the APT system and the ET system. The on-off switch is connected in series to a capacitive element connected between a path and the ground. The connection terminal is connected to the capacitive element. Moreover, the control circuit overlies the connection terminal in plan view in the thickness direction of the mount board.

Abstract: A radio frequency module includes: a module board including a first principal surface and a second principal surface on opposite sides of the module board; a transmission input terminal; a first transmission amplifier disposed on the first principal surface that amplifies a transmission signal input through the transmission input terminal; and a first switch disposed on the second principal surface that connects and disconnects the transmission input terminal and the first transmission amplifier.

Abstract: A front-end module includes: a switch module that performs CA for bands A and C and performs non-CA for band B, which is located between these two bands, and that has a common terminal and selection terminals; a duplexer that is connected to the selection terminal and allows band A to pass therethrough; a duplexer that is connected to the selection terminal and allows band C to pass therethrough; an impedance matching network that is connected to the selection terminal; and a reception filter that is connected to the impedance matching network and allows band B to pass therethrough. During CA for bands A and C, a first circuit, which includes the impedance matching network and the reception filter, forms an attenuation pole in the frequency band of band C in the transmission characteristic of a path connecting the duplexer, the common terminal, and the duplexer to each other.

Abstract: A radio frequency module includes a mount board, an acoustic wave filter, a temperature sensor, and a correction circuit. The mount board has a first principal surface and a second principal surface on opposite sides of the mount board. The acoustic wave filter is disposed on the first principal surface side of the mount board. The temperature sensor is disposed on the second principal surface side of the mount board. The correction circuit corrects a pass band of the acoustic wave filter in accordance with a temperature measured by the temperature sensor.

Abstract: A high-frequency module includes an antenna terminal, a transmission signal terminal, a reception signal terminal, a plurality of earth terminals, a switch, a transmission filter, a reception filter, and a multilayer board. The multilayer board includes a ground electrode arranged between the transmission filter and the reception filter. The plurality of earth terminals include a first earth terminal and a second earth terminal. When the high-frequency module is viewed in a direction perpendicular to a principal surface of the multilayer board, the reception signal terminal is provided between the antenna terminal and the transmission signal terminal, the first earth terminal is provided between the antenna terminal and the reception signal terminal, and the second earth terminal is provided between the reception signal terminal and the transmission signal terminal.

Abstract: A front-end module includes: a switch module that performs CA for bands A and C and performs non-CA for band B, which is located between these two bands, and that has a common terminal and selection terminals; a duplexer that is connected to the selection terminal and allows band A to pass therethrough; a duplexer that is connected to the selection terminal and allows band C to pass therethrough; an impedance matching network that is connected to the selection terminal; and a reception filter that is connected to the impedance matching network and allows band B to pass therethrough. During CA for bands A and C, a first circuit, which includes the impedance matching network and the reception filter, forms an attenuation pole in the frequency band of band C in the transmission characteristic of a path connecting the duplexer, the common terminal, and the duplexer to each other.

Abstract: A radio frequency module includes: a module substrate including a principal surface; a bump electrode that is disposed on the principal surface and configured as an external-connection terminal of the radio frequency module; a semiconductor IC that is disposed on the principal surface and includes a low-noise amplifier that amplifies a radio frequency reception signal; an under-fill material disposed in a gap between the semiconductor IC and the principal surface; and a surface mount device disposed on the principal surface, between the bump electrode and the semiconductor IC, wherein in a plan view of the module substrate, an outer edge of the under-fill material is located between an edge of the inductor and an edge of the semiconductor IC, the respective edges of the inductor and semiconductor IC oppose the bump electrode.

Abstract: A radio frequency module includes: a module board including a first principal surface and a second principal surface on opposite sides of the module board; a transmission input terminal; a first transmission amplifier disposed on the first principal surface that amplifies a transmission signal input through the transmission input terminal; and a first switch disposed on the second principal surface that connects and disconnects the transmission input terminal and the first transmission amplifier.

Abstract: A coupler-integrated board includes a coupler, a first capacitor, a second capacitor, a resistance element, a matching circuit, and a multilayer circuit board. The coupler includes a main line and a secondary line. The first capacitor is connected in parallel with the secondary line. The second capacitor connects another end of the secondary line to a ground. The resistance element connects the other end of the secondary line to the ground. The resistance element has an impedance lower than a normalized impedance at a predetermined frequency. The matching circuit is connected between one end of the secondary line and a coupling port. The matching circuit matches an impedance at the coupling port to the normalized impedance at the predetermined frequency. The multilayer circuit board includes laminated base material layers. The coupler is integrated with the multiplayer circuit board.

Abstract: A multiplexer includes: a switch capable of connecting a common terminal to at least one of a first selection terminal, a second selection terminal, and a third selection terminal at the same time; a first filter connected to the first selection terminal, the first filter having a first pass band; a second filter connected to the second selection terminal, the second filter having a second pass band that is different from the first pass band; and a coupling circuit connected to the third selection terminal and the first filter, the coupling circuit forming a signal path between the third selection terminal and the first filter by electromagnetic coupling.

Abstract: A high-frequency module includes an antenna terminal, a transmission signal terminal, a reception signal terminal, a plurality of earth terminals, a switch, a transmission filter, a reception filter, and a multilayer board. The multilayer board includes a ground electrode arranged between the transmission filter and the reception filter. The plurality of earth terminals include a first earth terminal and a second earth terminal. When the high-frequency module is viewed in a direction perpendicular to a principal surface of the multilayer board, the reception signal terminal is provided between the antenna terminal and the transmission signal terminal, the first earth terminal is provided between the antenna terminal and the reception signal terminal, and the second earth terminal is provided between the reception signal terminal and the transmission signal terminal.

Abstract: A front end module that performs a CA method includes a signal path through which a signal of a first frequency band propagates, a signal path through which a signal of a second frequency band propagates, a switch module that includes antenna terminals and selection terminals and is connected to antenna elements, and a balun that is disposed at the signal path. First and second balanced terminals of the balun are connected to the selection terminals, and the balun causes a fundamental wave or harmonic of a transmission signal of the first frequency band input through an unbalanced terminal to branch into branch signals having opposite phases and outputs the branch signals to the first balanced terminal and the second balanced terminal.

Abstract: A coupler-integrated board includes a coupler, a first capacitor, a second capacitor, a resistance element, a matching circuit, and a multilayer circuit board. The coupler includes a main line and a secondary line. The first capacitor is connected in parallel with the secondary line. The second capacitor connects another end of the secondary line to a ground. The resistance element connects the other end of the secondary line to the ground. The resistance element has an impedance lower than a normalized impedance at a predetermined frequency. The matching circuit is connected between one end of the secondary line and a coupling port. The matching circuit matches an impedance at the coupling port to the normalized impedance at the predetermined frequency. The multilayer circuit board includes laminated base material layers. The coupler is integrated with the multiplayer circuit board.

Abstract: A front end module that performs a CA method includes a signal path through which a signal of a first frequency band propagates, a signal path through which a signal of a second frequency band propagates, a switch module that includes antenna terminals and selection terminals and is connected to antenna elements, and a balun that is disposed at the signal path. First and second balanced terminals of the balun are connected to the selection terminals, and the balun causes a fundamental wave or harmonic of a transmission signal of the first frequency band input through an unbalanced terminal to branch into branch signals having opposite phases and outputs the branch signals to the first balanced terminal and the second balanced terminal.