Multi-input amplifier with degeneration switching without the use of switches

A front-end module comprising:

• a packaging substrate;
• a variable-gain signal amplifier implemented on the packaging substrate, the variable-gain signal amplifier including an input node configured to receive an input signal;
• the variable-gain signal amplifier also including an output node configured to provide an amplified output signal;
• the variable-gain signal amplifier also including a plurality of active cores configured to provide a corresponding plurality of gain modes, the plurality of active cores coupled to the input node and to the output node such that there is a plurality of amplification paths between the input node and the output node corresponding to the plurality of active cores and the plurality of gain modes with a particular amplification path corresponding to a particular gain mode, each active core of the plurality of active cores configured to receive the input signal from the input node and to generate the amplified output signal at the output node with a gain characteristic corresponding to the gain mode of the amplification path;
• the variable-gain signal amplifier also including a gain mode selector having a plurality of switches that are configured to direct the input signal along a particular amplification path of the plurality of amplification paths according to the gain mode that corresponds to the amplification path;
• and the variable-gain signal amplifier also including a degeneration matrix having a plurality of inductance paths that are configured to provide a plurality of tailored inductances each inductance path providing a tailored inductance that corresponds to a gain mode of the plurality of gain modes, the inductance path through the degeneration matrix determined by the plurality of switches in the gain mode selector so that the degeneration matrix does not include any switches.

A wireless device comprising:

• an antenna;
• a filter assembly coupled to the antenna to receive signals and to direct frequency bands along selected paths;
• and
• a variable-gain signal amplifier including an input node configured to receive an input signal;
• the variable-gain signal amplifier also including an output node configured to provide an amplified output signal;
• the variable-gain signal amplifier also including a plurality of active cores configured to provide a corresponding plurality of gain modes, the plurality of active cores coupled to the input node and to the output node such that there is a plurality of amplification paths between the input node and the output node corresponding to the plurality of active cores and the plurality of gain modes with a particular amplification path corresponding to a particular gain mode, each active core of the plurality of active cores configured to receive the input signal from the input node and to generate the amplified output signal at the output node with a gain characteristic corresponding to the gain mode of the amplification path;
• the variable-gain signal amplifier also including a gain mode selector having a plurality of switches that are configured to direct the input signal along a particular amplification path of the plurality of amplification paths according to the gain mode that corresponds to the amplification path;
• and the variable-gain signal amplifier also including a degeneration matrix having a plurality of inductance paths that are configured to provide a plurality of tailored inductances each inductance path providing a tailored inductance that corresponds to a gain mode of the plurality of gain modes, the inductance path through the degeneration matrix determined by the plurality of switches in the gain mode selector so that the degeneration matrix does not include any switches.