# US 12,003,218 B2 · Mixer with filtering function and method for linearization of mixer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,218 B2 - Document ID: US12003218B2 - Status: Granted - Kind: B2 - Application number: 17/947,192 - Filed: 2022-09-19 - Published: 2023-04-06 - Granted: 2024-06-04 - Earliest claimed: 2021-10-06 - Assignees: Mediatek Inc. - Applicants: Mediatek Inc. - Inventors: Tse-Yu Chen; Chun-Wei Lin - Web page: https://patentgrep.com/patent/US12003218B2 ## CPC - H03D 7/1491: {Arrangements to linearise a transconductance stage of a mixer arrangement} - H03D 7/12: by means of semiconductor devices having more than two electrodes (H03D7/14 - H03D7/22 take precedence) - H03D 7/1441: {using field-effect transistors (H03D7/145 takes precedence)} - H03F 3/195: in integrated circuits - H03F 3/45183: {Long tailed pairs (H03F3/4521, H03F3/45237 take precedence)} - H03F 3/45475: {using IC blocks as the active amplifying circuit} - H03F 2200/447: the amplifier being protected to temperature influence - H03F 2200/451: the amplifier being a radio frequency amplifier - H03F 2203/45526: the FBC comprising a resistor-capacitor combination and being coupled between the LC and the IC - H03H 11/126: {using a single operational amplifier (H03H11/1204 takes precedence; parallel-T filters H03H11/1295)} - H03D: DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER (masers, lasers H01S; circuits capable of acting both as modulator and demodulator H03C; details applicable to both modulators and frequency-changers H03C; demodulating pulses H03K9/00; transforming types of pulse modulation H03K11/00; coding, decoding or code conversion, in general H03M; repeater stations H04B7/14; demodulators adapted for AC systems of digital information transmission H04L27/00; synchronous demodulators adapted for colour television H04N9/66) - H03F: AMPLIFIERS - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) ## Abstract A mixer with a filtering function and a method for linearization of the mixer are provided. The mixer includes at least one amplifier, a transconductance device and a feedback network. The at least one amplifier is configured to output a filtered voltage signal according to an input voltage signal. The transconductance device is coupled to the at least one amplifier, and is configured to generate a filtered current signal according to the filtered voltage signal. The feedback network is coupled between any output terminal among at least one output terminal of the transconductance device and an input terminal of the at least one amplifier. More particularly, the mixer is configured to output a modulated signal according to the filtered current signal. ## Claims ### Claim 1 A mixer with a filtering function, comprising: at least one amplifier, configured to output a filtered voltage signal according to an input voltage signal; a transconductance device, coupled to the at least one amplifier, configured to receive the filtered voltage from the at least one amplifier and generate a filtered current signal according to the filtered voltage signal, wherein the transconductance device comprises a transistor, and a gate terminal of the transistor is configured to receive the filtered voltage signal; and a feedback network, coupled between any output terminal among at least one output terminal of the transconductance device and an input terminal of the at least one amplifier, wherein the feedback network is coupled between a source terminal of the transistor and the input terminal of the at least one amplifier; wherein the mixer is configured to output a modulated signal according to the filtered current signal. ### Claim 2 (depends on 1) The mixer of claim 1, further comprising: an input resistor, coupled to the input terminal of the at least one amplifier, configured to receive the input voltage signal. ### Claim 3 (depends on 1) The mixer of claim 1, further comprising: a source resistor, coupled between a reference voltage terminal and a source terminal of the transistor. ### Claim 4 A mixer with a filtering function, comprising: at least one amplifier, configured to output a filtered voltage signal according to an input voltage signal; a transconductance device, coupled to the at least one amplifier, configured to receive the filtered voltage from the at least one amplifier and generate a filtered current signal according to the filtered voltage signal; and a feedback network, comprising a resistor-capacitor network, wherein one terminal of the resistor-capacitor network is directly coupled to any output terminal among at least one output terminal of the transconductance device, and another terminal of the resistor-capacitor network is directly coupled to an input terminal of the at least one amplifier; wherein the mixer is configured to output a modulated signal according to the filtered current signal. ### Claim 5 (depends on 4) The mixer of claim 4, wherein the resistor-capacitor network comprises a feedback resistor and a feedback capacitor connected in parallel between the any output terminal of the transconductance device and the input terminal of the at least one amplifier. ### Claim 6 A method for linearization of a mixer, comprising: utilizing at least one amplifier of the mixer to output a filtered voltage signal according to an input voltage signal; utilizing a transconductance device of the mixer to receive the filtered voltage from the at least one amplifier and generate a filtered current signal according to the filtered voltage signal, wherein the transconductance device comprises a transistor, and a gate terminal of the transistor is configured to receive the filtered voltage signal; and utilizing a feedback network of the mixer to provide a feedback path from any output terminal among at least one output terminal of the transconductance device to an input terminal of the at least one amplifier, wherein the feedback network is coupled between a source terminal of the transistor and the input terminal of the at least one amplifier; wherein the mixer is configured to output a modulated signal according to the filtered current signal. ### Claim 7 (depends on 6) The method of claim 6, wherein the feedback network comprises a resistor-capacitor network coupled between the any output terminal of the transconductance device and the input terminal of the at least one amplifier. ### Claim 8 (depends on 7) The method of claim 7, wherein the resistor-capacitor network comprises a feedback resistor and a feedback capacitor connected in parallel between the any output terminal of the transconductance device and the input terminal of the at least one amplifier. ### Claim 9 (depends on 6) The method of claim 6, further comprising: utilizing an input resistor coupled to the input terminal of the at least one amplifier to receive the input voltage signal. ### Claim 10 (depends on 6) The method of claim 6, wherein a source resistor is coupled between a reference voltage terminal and a source terminal of the transistor.