A stacked composite filter device includes a stacked body having a first region and a second region that are different from each other. A first filter includes a first inductor and has a first pass band is arranged in the first region. A second filter includes a second inductor and has a second pass band on a lower frequency side than the first pass band is arranged in the second region. A first conductive structure extends in a stacking direction of the stacked body and includes one end grounded that is arranged in an area that is in the first region and adjacent to the second region. The other end of the first conductive structure is connected to the first inductor.

A stacked composite filter device includes a stacked body having a first region and a second region that are different from each other. A first filter includes a first inductor and has a first pass band is arranged in the first region. A second filter includes a second inductor and has a second pass band on a lower frequency side than the first pass band is arranged in the second region. A first conductive structure extends in a stacking direction of the stacked body and includes one end grounded that is arranged in an area that is in the first region and adjacent to the second region. The other end of the first conductive structure is connected to the first inductor.

A filter device having a pass band and a stop band on a lower frequency side than the pass band includes a filter having a pass band including the pass band, a series arm resonator connected in series to the filter, a first inductor directly connected in series to the series arm resonator, and a parallel arm resonator connected between a node on a path connecting the filter and the series arm resonator and the ground. The parallel arm resonator constitutes a resonance circuit having a resonant frequency at which an attenuation pole corresponding to a high frequency end of the first stop band, and the series arm resonator and the inductor constitute a resonance circuit having an anti-resonant frequency on a lower frequency side than the pass band and having a sub-resonant frequency higher than a resonant frequency of the resonance circuit.

A filter device having a pass band and a stop band on a lower frequency side than the pass band includes a filter having a pass band including the pass band, a series arm resonator connected in series to the filter, a first inductor directly connected in series to the series arm resonator, and a parallel arm resonator connected between a node on a path connecting the filter and the series arm resonator and the ground. The parallel arm resonator constitutes a resonance circuit having a resonant frequency at which an attenuation pole corresponding to a high frequency end of the first stop band, and the series arm resonator and the inductor constitute a resonance circuit having an anti-resonant frequency on a lower frequency side than the pass band and having a sub-resonant frequency higher than a resonant frequency of the resonance circuit.

A high frequency filter includes series arm resonators and parallel arm resonators as acoustic wave resonators and at least one inductor, wherein capacitive components of the acoustic wave resonators constitute an LPF and an HPF as hybrid filters with an inductor or with an inductor and a capacitor, and the at least one inductor includes inductors as mount component inductors.

To achieve space saving and a reduction in cost. A radio-frequency module includes a band pass filter, a first low noise amplifier, a second low noise amplifier, and an attenuation filter. The band pass filter has an output terminal and allows the passage of a first reception signal and a second reception signal. The first low noise amplifier is connected to the output terminal of the band pass filter and amplifies the first reception signal. The second low noise amplifier is connected to the output terminal of the band pass filter and amplifies the second reception signal. The attenuation filter is provided on a common path between the output terminal of the band pass filter and the first low noise amplifier and between the output terminal of the band pass filter and the second low noise amplifier.

A hybrid filter includes a module substrate having a major surface and a major surface that are opposite to each other, acoustic wave resonator elements disposed at the module substrate, inductors disposed at the module substrate, and a capacitor disposed at the module substrate. The pass band of the hybrid filter is wider than the resonance band width of the acoustic wave resonator elements. One of the acoustic wave resonator elements, the inductors, and the capacitor is a first circuit element, and the first circuit element is disposed at the major surface. Another of the acoustic wave resonator elements, the inductors, and the capacitor is a second circuit element, and the second circuit element is disposed at the major surface.

A band-pass filter includes a first input/output port, a second input/output port, a first high-pass filter, a first low-pass filter, and a first stub resonator. The first stub resonator includes a first distributed constant line. The first low-pass filter is provided between the first input/output port and the first high-pass filter in the circuit configuration. The first distributed constant line has a first end connected to a first path connecting the first input/output port and the first low-pass filter, and a second end closest to a ground in the circuit configuration.

A band-pass filter includes a first input/output port, a second input/output port, a first high-pass filter, a first low-pass filter, and a first stub resonator. The first stub resonator includes a first distributed constant line. The first low-pass filter is provided between the first input/output port and the first high-pass filter in the circuit configuration. The first distributed constant line has a first end connected to a first path connecting the first input/output port and the first low-pass filter, and a second end closest to a ground in the circuit configuration.

A power distribution/coupling circuit includes a common terminal, first and second terminals, a first connection point, a first inductor connected between the first connection point and the first terminal, a second inductor connected between the first connection point and the second terminal, a first capacitor connected between an end of the first inductor closer to the first terminal and a ground, a second capacitor connected between an end of the second inductor closer to the second terminal and the ground, a third capacitor connected between the first connection point and the ground, and a resistor connected between the first terminal and the second terminal, wherein the power distribution/coupling circuit further includes a third inductor connected between the common terminal and the first connection point and a fourth capacitor connected between an end of the third inductor closer to the common terminal and the ground.