Abstract: A multiplexer includes: a first filter connected between a common terminal and a first terminal; a second filter connected between the common terminal and a second terminal, and having a passband lower in frequency than a passband of the first filter; and a resonant circuit including: a first inductor and a capacitor connected in series between a first end and a second end of the resonant circuit, the first end being coupled to a node at which the common terminal diverges into the first filter and the second filter, the second end being coupled to the first filter, and a second inductor connected in parallel to the first inductor and the capacitor between the first end and the second end, wherein the passband of the first filter is higher in frequency than an antiresonant frequency of the resonant circuit.

Abstract: An electronic device includes: a first substrate, a first function part in its first surface, an adhesive layer on the first surface so as to surround the first function part, a second substrate bonded to the first substrate by the adhesive layer to form a gap between the first and second substrates, a first via interconnection piercing the first substrate to connect the first surface and an opposite second surface, a second via interconnection piercing the second substrate to connect a third surface of the second substrate opposite to the first substrate and a fourth surface opposite to the third surface, a first terminal provided on the second surface and connected to the first via interconnection, a second terminal provided on the fourth surface and connected to the second via interconnection. The first function part is connected to at least one of the first and second via interconnections.

Abstract: A multiplexer includes: a first filter connected between a common terminal and a first terminal; a second filter connected between the common terminal and a second terminal, and having a passband lower in frequency than a passband of the first filter; and a resonant circuit including: a first inductor and a capacitor connected in series between a first end and a second end of the resonant circuit, the first end being coupled to a node at which the common terminal diverges into the first filter and the second filter, the second end being coupled to the first filter, and a second inductor connected in parallel to the first inductor and the capacitor between the first end and the second end, wherein the passband of the first filter is higher in frequency than an antiresonant frequency of the resonant circuit.

Abstract: A multilayer substrate is configured by stacking conductive layers and insulation layers. The multilayer substrate includes a core that is one of the conductive layers and is thicker than any of other conductive layers, and a first signal line that is included in the conductive layers and is adjacent to the core so that a first insulation layer that is one of the insulation layers is interposed between the core and the first signal line, the first signal line being used for transmission of an RF signal. The core has a recess portion so as to face the first signal line.

Abstract: A circuit substrate includes: a laminate substrate in which a conductive layer and an insulating layer are laminated; a filter chip that has an acoustic wave filter and is provided inside of the laminate substrate; and an active component that is provided on a surface of the laminate substrate and is connected with the filter chip, at least a part of the active component overlapping with a projected region that is a region of the filter chip projected in a thickness direction of the laminate substrate.

Abstract: An electronic device includes: a first substrate, a first function part in its first surface, an adhesive layer on the first surface so as to surround the first function part, a second substrate bonded to the first substrate by the adhesive layer to form a gap between the first and second substrates, a first via interconnection piercing the first substrate to connect the first surface and an opposite second surface, a second via interconnection piercing the second substrate to connect a third surface of the second substrate opposite to the first substrate and a fourth surface opposite to the third surface, a first terminal provided on the second surface and connected to the first via interconnection, a second terminal provided on the fourth surface and connected to the second via interconnection. The first function part is connected to at least one of the first and second via interconnections.

Abstract: A circuit substrate includes: a laminate substrate in which a conductive layer and an insulating layer are laminated; a filter chip that has an acoustic wave filter and is provided inside of the laminate substrate; and a chip component that is provided on a surface of the laminate substrate and is connected to the filter chip, at least a part of the chip component overlapping with a projected region that is a region of the filter chip projected in a thickness direction of the laminate substrate.

Abstract: A circuit substrate includes: a laminate substrate in which a conductive layer and an insulating layer are laminated; a filter chip that has an acoustic wave filter and is provided inside of the laminate substrate; and a chip component that is provided on a surface of the laminate substrate and is connected to the filter chip, at least a part of the chip component overlapping with a projected region that is a region of the filter chip projected in a thickness direction of the laminate substrate.

Abstract: A multilayer substrate is configured by stacking conductive layers and insulation layers. The multilayer substrate includes a core that is one of the conductive layers and is thicker than any of other conductive layers, and a first signal line that is included in the conductive layers and is adjacent to the core so that a first insulation layer that is one of the insulation layers is interposed between the core and the first signal line, the first signal line being used for transmission of an RF signal. The core has a recess portion so as to face the first signal line.

Abstract: A multilayer substrate is configured by stacking conductive layers and insulation layers. The multilayer substrate includes a core that is one of the conductive layers and is thicker than any of other conductive layers, and a first signal line that is included in the conductive layers and is adjacent to the core so that a first insulation layer that is one of the insulation layers is interposed between the core and the first signal line, the first signal line being used for transmission of an RF signal. The core has a recess portion so as to face the first signal line.

Abstract: A multilayer substrate is configured by stacking conductive layers and insulation layers. The multilayer substrate includes a core that is one of the conductive layers and is thicker than any of other conductive layers, and a first signal line that is included in the conductive layers and is adjacent to the core so that a first insulation layer that is one of the insulation layers is interposed between the core and the first signal line, the first signal line being used for transmission of an RF signal. The core has a recess portion so as to face the first signal line.