# US 2021/0242897 A1 · Radio front end module with reduced loss and increased linearity > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242897 A1 - Document ID: US20210242897A1 - Status: Published application - Kind: A1 - Application number: 17/236,272 - Filed: 2021-04-21 - Published: 2021-08-05 - Earliest claimed: 2018-11-27 - Assignees: Skyworks Solutions, Inc. - Applicants: Skyworks Solutions, Inc. - Inventors: Foad Arfaei Malekzadeh; Sanjeev Jain; Stephen Joseph Kovacic - Web page: https://patentgrep.com/patent/US20210242897A1 ## CPC - H04B 1/0475: {with means for limiting noise, interference or distortion (H04B1/0483 takes precedence)} - H04B 1/40: Circuits - H03F 1/3211: {in differential amplifiers} - H03F 1/56: Modifications of input or output impedances, not otherwise provided for - H03F 3/19: with semiconductor devices only - H03F 3/213: in integrated circuits - H03F 3/245: {with semiconductor devices only} - H03F 3/45071: {with semiconductor devices only} - H03F 3/68: Combinations of amplifiers, e.g. multi-channel amplifiers for stereophonics {(power amplifiers using a combination of several semiconductor amplifiers H03F3/211; combinations of amplifiers using coupling networks with distributed constants H03F3/602)} - H04B 1/0483: {Transmitters with multiple parallel paths} - H04B 1/525: with means for reducing leakage of transmitter signal into the receiver - H03F 2200/06: A balun, i.e. balanced to or from unbalanced converter, being present at the input of an amplifier - H03F 2200/09: A balun, i.e. balanced to or from unbalanced converter, being present at the output of an amplifier - H03F 2200/192: A hybrid coupler being used at the input of an amplifier circuit - H03F 2200/204: A hybrid coupler being used at the output of an amplifier circuit - H03F 2200/222: A circuit being added at the input of an amplifier to adapt the input impedance of the amplifier - H03F 2200/294: the amplifier being a low noise amplifier [LNA] - H03F 2200/451: the amplifier being a radio frequency amplifier - H04B: TRANSMISSION - H03F: AMPLIFIERS ## Abstract A Radio Frequency (RF) circuit including a receive path, a transmit path, a switching circuit, and an output configured to receive RF signals from an antenna in a receive mode of operation, and to provide RF signals to the antenna in a transmit mode of operation. The receive path is configured to be coupled between a low-noise amplifier and the output. The switching circuit is located in the receive path and is configured, in the receive mode, to selectively couple the low-noise amplifier to the output and to pass the received RF signals from the output to the low-noise amplifier. The transmit path is configured to be coupled between a power amplifier and the output, to provide, in the transmit mode, signals from the power amplifier to the output, bypassing the switching circuit, and to have, in receive mode of operation, an off-state impedance of at least 200+j*13 Ohm. ## Claims ### Claim 1 A front-end module for a wireless device comprising: an input port to receive an input radio frequency signal; a power amplifier coupled to the input port to amplify the input radio frequency signal and provide a first radio frequency signal responsive to being enabled, and to present an off-state impedance of at least 200 Ohms responsive to being disabled; an antenna port configured to be coupled to an antenna, to receive a second radio frequency signal from the antenna in a receive mode of operation and to transmit the first radio frequency signal from the power amplifier to the antenna in a transmit mode of operation; a low-noise amplifier coupled to the antenna port to amplify the second radio frequency signal and provide the amplified second radio frequency signal to an output port; a switching circuit disposed between the low-noise amplifier and the antenna port to selectively couple the low-noise amplifier to the antenna port; and a controller coupled to the switching circuit, the power amplifier, and the low-noise amplifier, the controller being configured to cause the switching circuit to close and to disable the power amplifier in the receive mode of operation, and to cause the switching circuit to open in the transmit mode of operation. ### Claim 2 (depends on 1) The front-end module of claim 1 wherein the controller is further configured, in the receive mode of operation, to transmit an enable control signal to the low-noise amplifier and a disable control signal to the power amplifier. ### Claim 3 (depends on 1) The front-end module of claim 1 wherein the controller is further configured, in the transmit mode of operation, to transmit an enable control signal to the power amplifier and a disable control signal to the low-noise amplifier. ### Claim 4 (depends on 1) The front-end module of claim 1 wherein the controller is further configured, in the transmit mode of operation, to transmit an enable control signal to the power amplifier in response to the switching circuit opening and to transmit a disable control signal to the low-noise amplifier in response to the power amplifier being enabled. ### Claim 5 (depends on 1) The front-end module of claim 1 wherein the controller is further configured, in the receive mode of operation, to: transmit a disable control signal to the power amplifier; cause the switching circuit to close in response to the power amplifier being disabled; and transmit an enable control signal to the low-noise amplifier in response to the switching circuit closing. ### Claim 6 (depends on 1) The front-end module of claim 1 wherein the low-noise amplifier includes a differential amplifier, a first balun coupled between the differential amplifier and the switching circuit, and a second balun coupled between the differential amplifier and the output port. ### Claim 7 (depends on 1) The front-end module of claim 1 wherein the input radio frequency signal has a frequency in a 34-36 GHz range and the power amplifier is further configured to amplify the input RF signal having a frequency in the 34-36 GHz range. ### Claim 8 (depends on 1) The front-end module of claim 1 wherein the power amplifier is further configured, in the receive mode of operation, to have an off-state impedance of at least 200+j*13 Ohm. ### Claim 9 (depends on 1) The front-end module of claim 1 wherein the power amplifier, the low-noise amplifier, and the switching circuit are integrated into a single semiconductor die. ### Claim 10 (depends on 9) The front-end module of claim 9, where the single semiconductor die is a CMOS die. ### Claim 11 A front-end module comprising: an input port to receive an input radio frequency signal; a power amplifier module coupled to the input port to amplify the input radio frequency signal and provide a first radio frequency signal responsive to being enabled; an antenna port configured to be coupled to an antenna to receive a second radio frequency signal in a receive mode of operation and to transmit the first radio frequency signal from the power amplifier in a transmit mode of operation; a first balun coupled between the power amplifier module and the antenna port; a low-noise amplifier coupled to the antenna port to amplify the second radio frequency signal and provide the amplified second radio frequency signal to an output port; and a switching circuit disposed between the low-noise amplifier and the antenna port to selectively couple the low-noise amplifier to the antenna port to pass the second radio frequency signal from the antenna port to the low-noise amplifier, the switching circuit, the power amplifier module, the first balun, and the low-noise amplifier being integrated into a single semiconductor die. ### Claim 12 (depends on 11) The front-end module of claim 11 further comprising a second balun coupled between the low-noise amplifier and the output port. ### Claim 13 (depends on 12) The front-end module of claim 12 wherein the switching circuit, the power amplifier module, the first balun, the second balun, and the low-noise amplifier are integrated into the single semiconductor die, the single semiconductor die being a CMOS die. ### Claim 14 (depends on 12) The front-end module of claim 12 wherein the power amplifier module includes a first power amplifier and a second power amplifier, the first balun coupled between the first power amplifier and the antenna, and the second balun coupled between the second power amplifier and the antenna. ### Claim 15 (depends on 11) The front-end module of claim 11 wherein the power amplifier module and the first balun present an impedance of at least 200 Ohms responsive to the power amplifier module being disabled. ### Claim 16 (depends on 11) The front-end module of claim 11 wherein the low-noise amplifier includes an input impedance matching network, and the switching circuit is implemented as part of the impedance matching network. ### Claim 17 (depends on 11) The front-end module of claim 11 wherein the transmit signal has a frequency in a 34-36 GHz range and the power amplifier is further configured to amplify the transmit signal having a frequency in the 34-36 GHz range. ### Claim 18 A multiple-input and multiple-output integrated circuit comprising: an antenna to transmit a first radio frequency signal in a transmit mode of operation and to receive a second signal in a receive mode of operation; and a plurality of front-end modules coupled to the antenna, each front-end module including: an input port to receive an input radio frequency signal; a power amplifier coupled to the input port to amplify the input radio frequency signal, to provide a first radio frequency signal responsive to being enabled, and to present an off-state impedance of at least 200 Ohms responsive to being disabled; a low-noise amplifier coupled to the antenna to amplify the second radio frequency signal from the antenna; a first balun coupled between the power amplifier and the antenna; and a switching circuit disposed between the low-noise amplifier and the antenna to selectively couple the low-noise amplifier to the antenna to pass the second radio frequency signal from the antenna to the low-noise amplifier, the switching circuit, the power amplifier, the first balun, and the low-noise amplifier being integrated into a single semiconductor die. ### Claim 19 (depends on 18) The multiple-input and multiple-output integrated circuit of claim 18 further comprising a second balun coupled between the low-noise amplifier and an output port. ### Claim 20 (depends on 19) The multiple-input and multiple-output integrated circuit of claim 19 wherein the switching circuit, the power amplifier, the first balun, the second balun, and the low-noise amplifier are integrated into the single semiconductor die, the single semiconductor die being a CMOS die. ### Claim 21 (depends on 18) The multiple-input and multiple-output integrated circuit of claim 18 wherein the low noise amplifier includes an impedance matching network integrated into the single semiconductor die. ### Claim 22 (depends on 18) The multiple-input and multiple-output integrated circuit of claim 18 wherein the input radio frequency signal has a frequency in a 34-36 GHz range and the power amplifier is configured to amplify the input radio frequency signal having a frequency in the 34-36 GHz range.