Radio-frequency filter, multiplexer, radio-frequency front-end circuit, and communication device

A multiplexer, comprising:

• a plurality of radio frequency filters that each include:
• a series-arm circuit disposed on a path that connects a first input/output terminal and a second input/output terminal;
• a first parallel-arm circuit connected to a ground and a first node on the path, between the first input/output terminal and the series-arm circuit, the first parallel-arm circuit including a first parallel-arm resonator, and a first switch circuit connected in series to the first parallel arm resonator;
• and
• a second parallel-arm circuit connected to the ground and a second node on the path, between the series-arm circuit and the second input/output terminal, the second parallel-arm circuit including a second parallel-arm resonator, and a second switch circuit connected in series to the second parallel-arm resonator, wherein
• the first switch circuit includes a first switch element that includes one or more semiconductor elements connected in series,
• the second switch circuit includes a second switch element that includes one or more semiconductor elements connected in series, and
• a first stack count that is a total number of the one or more semiconductor elements connected in series and included in the first switch element is lower than a second stack count that is a total number of the one or more semiconductor elements connected in series and included in the second switch, wherein
• input terminals or output terminals of the plurality of filters are directly or indirectly connected to a common terminal.

Circuitry for processing a radio-frequency signal, the circuitry comprising:

• one or more radio frequency filters, the one or more radio frequency filters each comprising
• a series-arm circuit disposed on a path that connects a first input/output terminal and a second input/output terminal;
• a first parallel-arm circuit connected to a ground and a first node on the path, between the first input/output terminal and the series-arm circuit, the first parallel-arm circuit including a first parallel-arm resonator, and a first switch circuit connected in series to the first parallel arm resonator;
• and
• a second parallel-arm circuit connected to the ground and a second node on the path, between the series-arm circuit and the second input/output terminal, the second parallel-arm circuit including a second parallel-arm resonator, and a second switch circuit connected in series to the second parallel-arm resonator, wherein
• the first switch circuit includes a first switch element that includes one or more semiconductor elements connected in series,
• the second switch circuit includes a second switch element that includes one or more semiconductor elements connected in series, and
• a first stack count that is a total number of the one or more semiconductor elements connected in series and included in the first switch element is lower than a second stack count that is a total number of the one or more semiconductor elements connected in series and included in the second switch;
• and
• an amplifier circuit directly or indirectly connected to the one or more radio frequency filters.