# US 10,374,650 B2 · Apparatus and methods for filter bypass for radio frequency front-ends > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,650 B2 - Document ID: US10374650B2 - Status: Granted - Kind: B2 - Application number: 16/132,033 - Filed: 2018-09-14 - Published: 2019-01-10 - Granted: 2019-08-06 - Earliest claimed: 2016-08-10 - Assignees: Skyworks Solutions, Inc. - Applicants: Skyworks Solutions, Inc. - Inventors: David Richard Pehlke; Stephane Richard Marie Wloczysiak - Web page: https://patentgrep.com/patent/US10374650B2 ## CPC - H04B 1/40: Circuits - H03F 3/19: with semiconductor devices only - H03F 3/72: Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal - H03F 2200/294: the amplifier being a low noise amplifier [LNA] - H03F 2200/451: the amplifier being a radio frequency amplifier - H03F 2203/7239: the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers and shunting lines by one or more switch(es) - H04B: TRANSMISSION - H03F: AMPLIFIERS ## Abstract Apparatus and methods for filter bypass for radio frequency front-ends are provided. In certain configurations, a front-end system includes a low noise amplifier, a blocker filter, a plurality of switches configured to control connectivity of the blocker filter and the low noise amplifier in a signal path through the front-end system. The front-end system further includes a controller configured to control the plurality of switches to operate the front-end system in a selected mode chosen from a plurality of modes. The plurality of modes includes a first mode in which the blocker filter is before the low noise amplifier in the signal path, and a second mode in which the low noise amplifier is before the blocker filter in the signal path. ## Claims ### Claim 1 A mobile device comprising: an antenna; a front-end system including a blocker filter, a low noise amplifier, and a plurality of switches; and a transceiver configured to receive a radio frequency signal from the antenna by way of a signal path through the front-end system, the transceiver configured to control the plurality of switches to operate the front-end system in a selected mode chosen from a plurality of modes, including a first mode in which the blocker filter is before the low noise amplifier in the signal path, and a second mode in which the low noise amplifier is before the blocker filter in the signal path. ### Claim 2 (depends on 1) The mobile device of claim 1 wherein the plurality of switches includes a first crosspoint switch and a second crosspoint switch, the low noise amplifier electrically connected between a first output of the first crosspoint switch and a first input of the second crosspoint switch, and the blocker filter connected between a second output of the first crosspoint switch and a second input of the second crosspoint switch. ### Claim 3 (depends on 2) The mobile device of claim 2 wherein an output of the second crosspoint switch is coupled to an input of the first crosspoint switch by a loopback path. ### Claim 4 (depends on 1) The mobile device of claim 1 wherein the plurality of switches includes a first switch connected between an output terminal and an output of the blocker filter, a second switch connected between the output terminal and an output of the low noise amplifier, and a third switch connected between the output terminal and an input terminal. ### Claim 5 (depends on 4) The mobile device of claim 4 wherein the plurality of switches further includes a fourth switch connected between the input terminal and an input to the low noise amplifier, a fifth switch connected between the input terminal and an input to the blocker filter, a sixth switched connected between the output of the low noise amplifier and the input to the blocker filter, and a seventh switch connected between the input of the low noise amplifier and the output of the blocker filter. ### Claim 6 (depends on 1) The mobile device of claim 1 wherein the plurality of modes further includes a third mode in which the blocker filter is in the signal path and the low noise amplifier is bypassed. ### Claim 7 (depends on 6) The mobile device of claim 6 wherein the plurality of modes further includes a fourth mode in which the low noise amplifier is in the signal path and the blocker filter is bypassed. ### Claim 8 (depends on 1) The mobile device of claim 1 wherein the transceiver includes a blocker detector configured to detect a blocker signal level of the radio frequency signal, the transceiver further configured to choose the selected mode based on the detected blocker signal level. ### Claim 9 (depends on 1) The mobile device of claim 1 wherein the transceiver is further configured to change a gain of the low noise amplifier based on the selected mode. ### Claim 10 (depends on 1) The mobile device of claim 1 wherein the transceiver includes an automatic gain control system configured to choose the selected mode. ### Claim 11 A front-end system for a radio frequency communication device, the front-end system comprising: a low noise amplifier; a blocker filter; a plurality of switches configured to control connectivity of the blocker filter and the low noise amplifier in a signal path through the front-end system; and a controller configured to control the plurality of switches to operate the front-end system in a selected mode chosen from a plurality of modes, the plurality of modes including a first mode in which the blocker filter is before the low noise amplifier in the signal path, and a second mode in which the low noise amplifier is before the blocker filter in the signal path. ### Claim 12 (depends on 11) The front-end system of claim 11 wherein the plurality of switches includes a first crosspoint switch and a second crosspoint switch, the low noise amplifier electrically connected between a first output of the first crosspoint switch and a first input of the second crosspoint switch, and the blocker filter connected between a second output of the first crosspoint switch and a second input of the second crosspoint switch. ### Claim 13 (depends on 12) The front-end system of claim 12 wherein an output of the second crosspoint switch is coupled to an input of the first crosspoint switch by a loopback path. ### Claim 14 (depends on 11) The front-end system of claim 11 wherein the plurality of switches includes a first switch connected between an output terminal and an output of the blocker filter, a second switch connected between the output terminal and an output of the low noise amplifier, and a third switch connected between the output terminal and an input terminal. ### Claim 15 (depends on 14) The front-end system of claim 14 wherein the plurality of switches further includes a fourth switch connected between the input terminal and an input to the low noise amplifier, a fifth switch connected between the input terminal and an input to the blocker filter, a sixth switched connected between the output of the low noise amplifier and the input to the blocker filter, and a seventh switch connected between the input of the low noise amplifier and the output of the blocker filter. ### Claim 16 (depends on 11) The front-end system of claim 11 wherein the plurality of modes further includes a third mode in which the blocker filter is in the signal path and the low noise amplifier is bypassed. ### Claim 17 (depends on 16) The front-end system of claim 16 wherein the plurality of modes further includes a fourth mode in which the low noise amplifier is in the signal path and the blocker filter is bypassed. ### Claim 18 A method of processing received signals in a mobile device, the method comprising: receiving a radio frequency signal using an antenna; processing the received signal using a signal path through a front-end system, the front-end system including a blocker filter, a low noise amplifier, and a plurality of switches; controlling the plurality of switches to operate the front-end system in a first mode in which the blocker filter is before the low noise amplifier in the signal path; and controlling the plurality of switches to operate the front-end system in a second mode in which the low noise amplifier is before the blocker filter in the signal path. ### Claim 19 (depends on 18) The method of claim 18 further comprising controlling the plurality of switches to operate the front-end system in a third mode in which the blocker filter is in the signal path and the low noise amplifier is bypassed. ### Claim 20 (depends on 19) The method of claim 19 further comprising controlling the plurality of switches to operate the front-end system in a fourth mode in which the low noise amplifier is in the signal path and the blocker filter is bypassed.