# US 2018/0323752 A1 · Apparatus and methods for overload protection of radio frequency amplifiers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0323752 A1 - Document ID: US20180323752A1 - Status: Published application - Kind: A1 - Application number: 15/941,554 - Filed: 2018-03-30 - Published: 2018-11-08 - Earliest claimed: 2017-04-11 - Assignees: Skyworks Solutions, Inc. - Applicants: Skyworks Solutions, Inc. - Inventors: Leslie Paul Wallis - Web page: https://patentgrep.com/patent/US20180323752A1 ## CPC - H03F 1/523: {for amplifiers using field-effect devices (H03F1/526 takes precedence)} - H03F 1/26: Modifications of amplifiers to reduce influence of noise generated by amplifying elements - H03F 1/565: {using inductive elements} - H03F 3/193: with field-effect devices (H03F3/195 takes precedence) - H03F 3/195: in integrated circuits - H03F 3/72: Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal - H03F 2200/111: the amplifier being a dual or triple band amplifier, e.g. 900 and 1800 MHz, e.g. switched or not switched, simultaneously or not - 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 2200/372: Noise reduction and elimination in amplifier - H03F 2200/411: the output amplifying stage of an amplifier comprising two power stages - H03F 2200/444: Diode used as protection means in an amplifier, e.g. as a limiter or as a switch - H03F 2200/451: the amplifier being a radio frequency amplifier - H03F 2203/7209: the gated amplifier being switched from a first band to a second band - H03F 2203/7215: the gated amplifier being switched on or off by a switch at the input of the amplifier - H03F 2203/7221: the gated amplifier being switched on or off by a switch at the output of the amplifier - H03F 2203/7236: the gated amplifier being switched on or off by putting into parallel or not, by choosing between amplifiers by (a ) switch(es) - H03F: AMPLIFIERS ## Abstract Radio frequency amplifiers with overload protection are provided herein. In certain configurations, an RF amplifier system includes an RF amplifier that receives an RF signal from an input terminal and that generates an amplified RF signal at an output terminal, and an overload detection circuit that generates a detection signal indicating a detected signal level of the RF amplifier. The RF amplifier includes an amplification device that amplifies the RF signal and a degeneration circuit that provides degeneration to the amplification device. Additionally, the detection signal is operable to control an amount of degeneration provided by the degeneration circuit so as to protect the RF amplifier from overload. ## Claims ### Claim 1 A radio frequency amplifier system comprising: an input terminal configured to receive a radio frequency signal; an output terminal; a radio frequency amplifier configured to receive the radio frequency signal from the input terminal and to generate an amplified radio frequency signal at the output terminal, the radio frequency amplifier including an amplification device configured to amplify the radio frequency signal and a degeneration circuit configured to provide degeneration to the amplification device; and an overload detection circuit configured to generate a detection signal indicating a detected signal level of the radio frequency amplifier, the detection signal operable to control an amount of degeneration provided by the degeneration circuit so as to protect the radio frequency amplifier from overload. ### Claim 2 (depends on 1) The radio frequency amplifier system of claim 1 further comprising an electrostatic discharge protection circuit electrically coupled to the input terminal and configured to protect the radio frequency amplifier from an electrostatic discharge event, the overload detection circuit integrated with the electrostatic discharge protection circuit. ### Claim 3 (depends on 2) The radio frequency amplifier system of claim 2 wherein the overload detection circuit is configured to generate the detection signal based on an internal signal level of the electrostatic discharge protection circuit. ### Claim 4 (depends on 2) The radio frequency amplifier system of claim 2 wherein the electrostatic discharge protection circuit includes a plurality of diodes in series, the overload detection circuit configured to generate the detection signal based on a voltage across one or more of the plurality of diodes. ### Claim 5 (depends on 1) The radio frequency amplifier system of claim 1 wherein the radio frequency amplifier is a low noise amplifier. ### Claim 6 (depends on 1) The radio frequency amplifier system of claim 1 wherein the detection signal is operable to increase the amount of degeneration provided by the degeneration circuit in response to the overload detection circuit detecting overload. ### Claim 7 (depends on 1) The radio frequency amplifier system of claim 1 wherein the degeneration circuit includes a switch and a control buffer configured to control the switch based on the detection signal. ### Claim 8 (depends on 7) The radio frequency amplifier system of claim 7 wherein the control buffer is powered in part by the detection signal. ### Claim 9 (depends on 7) The radio frequency amplifier system of claim 7 wherein the control buffer is configured to receive a digital control signal configured to control the switch. ### Claim 10 A packaged module comprising: a packaging substrate; and a semiconductor die attached to the packaging substrate, the semiconductor die including an input terminal and a radio frequency amplifier configured to receive a radio frequency signal from the input terminal, the radio frequency amplifier including an amplification device configured to amplify the radio frequency signal and a degeneration circuit configured to provide degeneration to the amplification device, the semiconductor die further including an overload detection circuit configured to generate a detection signal indicating a detected signal level of the radio frequency amplifier, the detection signal operable to control an amount of degeneration provided by the degeneration circuit so as to protect the radio frequency amplifier from overload. ### Claim 11 (depends on 10) The packaged module of claim 10 wherein the integrated circuit further includes an electrostatic discharge protection circuit electrically coupled to the input terminal and configured to provide protection against an electrostatic discharge event, the overload detection circuit integrated with the electrostatic discharge protection circuit. ### Claim 12 (depends on 11) The packaged module of claim 11 wherein the overload detection circuit is configured to generate the detection signal based on an internal signal level of the electrostatic discharge protection circuit. ### Claim 13 (depends on 11) The packaged module of claim 11 wherein the electrostatic discharge protection circuit includes a plurality of diodes in series, the overload detection circuit configured to generate the detection signal based on a voltage across one or more of the plurality of diodes. ### Claim 14 (depends on 10) The packaged module of claim 10 wherein the radio frequency amplifier is a low noise amplifier. ### Claim 15 (depends on 10) The packaged module of claim 10 wherein the amplification device includes a bipolar transistor, the degeneration circuit configured to provide emitter degeneration to the bipolar transistor. ### Claim 16 (depends on 10) The packaged module of claim 10 wherein the degeneration circuit includes a switch and a control buffer configured to control the switch based on the detection signal. ### Claim 17 (depends on 16) The packaged module of claim 16 wherein the control buffer is powered in part by the detection signal. ### Claim 18 A method of overload protection in a radio frequency amplifier system, the method comprising: receiving a radio frequency signal at an input terminal of a radio frequency amplifier; amplifying the radio frequency signal using an amplification device of the radio frequency amplifier; providing degeneration to the amplification device using a degeneration circuit of the radio frequency amplifier; generating a detection signal indicated a detected signal level of the radio frequency amplifier using an overload detection circuit; and protecting the radio frequency amplifier from overload by controlling an amount of degeneration provided by the degeneration circuit based on the detection signal. ### Claim 19 (depends on 18) The method of claim 18 further comprising providing electrostatic discharge protection to the input terminal using an electrostatic discharge protection circuit, and generating the detection signal based on an internal signal level of the electrostatic discharge protection circuit. ### Claim 20 (depends on 18) The method of claim 18 further comprising increasing the amount of degeneration using the detection signal in response to determining that the detected signal level indicates overload.