# US 10,483,940 B2 · High-performance conversion between single-ended and differential/common-mode signals > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,483,940 B2 - Document ID: US10483940B2 - Status: Granted - Kind: B2 - Application number: 16/255,170 - Filed: 2019-01-23 - Published: 2019-05-23 - Granted: 2019-11-19 - Earliest claimed: 2009-09-01 - Assignees: Maxlinear Israel LTD - Applicants: Maxlinear Israel Ltd. - Inventors: Nir Yahav; Ofer Rahmanony - Web page: https://patentgrep.com/patent/US10483940B2 ## CPC - H03H 7/42: Networks for transforming balanced signals into unbalanced signals and vice versa, e.g. baluns - H03H 7/38: Impedance-matching networks - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) ## Abstract A signal conversion apparatus includes first and second input ports and first and second output ports. A first splitter is coupled to convert a first single-ended signal received on the first input port into a differential signal including first and second opposite-phase components, and to provide the first and second opposite-phase components respectively on the first and second output ports. A second splitter is separate from the first splitter and is coupled to convert a second single-ended signal received on the second input port into a common-mode signal including first and second in-phase components, and to provide the first and second in-phase components respectively on the first and second output ports together with the first and second opposite-phase components. ## Claims ### Claim 1 A signal conversion apparatus, comprising: a first splitter configured to convert a radio frequency (RF) input signal into a first output signal and a second output signal, wherein the first output signal is out of phase with the second output signal, and wherein the first splitter is configured to convert a first input signal and a second input signal into an RF output signal; a second splitter configured to convert a local oscillator (LO) input signal into a third output signal and a fourth output signal, wherein the third output signal is in phase with the fourth output signal, and wherein the second splitter is configured to convert a third input signal and a fourth input signal into an LO output signal; a first passive circuit coupled to the first splitter and configured to add a first delay to the first output signal and the second output signal to produce a delayed first output signal at a first output port and a delayed second output signal at a second output port, wherein the first delay is configured according to a frequency band comprising the LO input signal; and a second passive circuit coupled to the second splitter and configured to add a second delay to the third output signal and the fourth output signal to produce a delayed third output signal together with the delayed first output signal at the first output port and a delayed fourth output signal together with the delayed second output signal at the second output port, wherein the second delay is configured according to a frequency band comprising the RF input signal. ### Claim 2 (depends on 1) The apparatus according to claim 1, wherein the first splitter comprises a balanced-to-unbalanced (balun) splitter. ### Claim 3 (depends on 1) The apparatus according to claim 1, wherein the second splitter comprises a power divider. ### Claim 4 (depends on 1) The apparatus according to claim 1, comprising ancillary circuitry configured to isolate the first splitter from the second splitter. ### Claim 5 (depends on 1) The apparatus according to claim 1, wherein the first and second splitters operate over different respective first and second frequency bands. ### Claim 6 (depends on 5) The apparatus according to claim 5, wherein the first passive circuit and the second passive circuit comprise delay lines, and wherein the first delay is equivalent to a quarter-wavelength in the second frequency band and the second delay is equivalent to a quarter-wavelength in the first frequency band. ### Claim 7 (depends on 6) The apparatus according to claim 6, wherein the delay lines comprise coupled transmission lines. ### Claim 8 (depends on 6) The apparatus according to claim 6, wherein the delay lines comprise inductors and capacitors. ### Claim 9 A mixer, comprising: a first splitter configured to convert a radio frequency (RF) input signal into a first output signal and a second output signal, wherein the first output signal is out of phase with the second output signal, and wherein the first splitter is configured to convert a first input signal and a second input signal into an RF output signal; a second splitter configured to convert a local oscillator (LO) input signal into a third output signal and a fourth output signal, wherein the third output signal is in phase with the fourth output signal, and wherein the second splitter is configured to convert a third input signal and a fourth input signal into an LO output signal; a first passive circuit coupled to the first splitter and configured to add a first delay to the first output signal and the second output signal to produce a delayed first output signal at a first output port and a delayed second output signal at a second output port, wherein the first delay is configured according to a frequency band comprising the LO input signal; a second passive circuit coupled to the second splitter and configured to add a second delay to the third output signal and the fourth output signal to produce a delayed third output signal together with the delayed first output signal at the first output port and a delayed fourth output signal together with the delayed second output signal at the second output port, wherein the second delay is configured according to a frequency band comprising the RF input signal; and mixing circuitry configured to combine a signal on the first output port with a signal on the second output port. ### Claim 10 A Radio Frequency Integrated Circuit (RFIC), comprising: a semiconductor substrate; and a signal conversion unit, which is fabricated on the semiconductor substrate the signal conversion unit comprising: a first splitter configured to convert a radio frequency (RF) input signal into a first output signal and a second output signal, wherein the first output signal is out of phase with the second output signal, and wherein the first splitter is configured to convert a first input signal and a second input signal into an RF output signal; a second splitter configured to convert a local oscillator (LO) input signal into a third output signal and a fourth output signal, wherein the third output signal is in phase with the fourth output signal, and wherein the second splitter is configured to convert a third input signal and a fourth input signal into an LO output signal; a first passive circuit coupled to the first splitter and configured to add a first delay to the first output signal and the second output signal to produce a delayed first output signal at a first output port and a delayed second output signal at a second output port, wherein the first delay is configured according to a frequency band comprising the LO input signal; and a second passive circuit coupled to the second splitter and configured to add a second delay to the third output signal and the fourth output signal to produce a delayed third output signal together with the delayed first output signal at the first output port and a delayed fourth output signal together with the delayed second output signal at the second output port, wherein the second delay is configured according to a frequency band comprising the RF input signal. ### Claim 11 (depends on 10) The RFIC according to claim 10, wherein the RFIC comprises mixing circuitry fabricated on the semiconductor substrate, and wherein the mixing circuitry is configured to combine a signal on the first output port with a signal on the second output port. ### Claim 12 A signal conversion method, comprising: using a first splitter to convert a radio frequency (RF) input signal into a first output signal and a second output signal, wherein the first output signal is out of phase with the second output signal; using a second splitter to convert a local oscillator (LO) input signal into a third output signal and a fourth output signal, wherein the third output signal is in phase with the fourth output signal; delaying the first output signal and the second output signal by a first delay, wherein the first delay is configured according to a frequency band comprising the LO input signal; delaying the third output signal and the fourth output signal by a second delay, wherein the second delay is configured according to a frequency band comprising the RF input signal; providing a sum of the delayed first output signal and a harmonic of the delayed third output signal on a first port, wherein the harmonic of the delayed third output signal is at a different frequency than the third output signal; and providing a sum of the delayed third output signal and a harmonic of the delayed fourth output signal on a second port, wherein the harmonic of the delayed fourth output signal is at a different frequency than the fourth output signal. ### Claim 13 (depends on 12) The method according to claim 12, wherein the first splitter comprises a balanced-to-unbalanced (balun) splitter. ### Claim 14 (depends on 12) The method according to claim 12, wherein the second splitter comprises a power divider. ### Claim 15 (depends on 12) The method according to claim 12, wherein the method comprises isolating the first splitter from the second splitter using ancillary circuitry. ### Claim 16 (depends on 12) The method according to claim 12, wherein the first and second splitters operate over different respective first and second frequency bands. ### Claim 17 (depends on 16) The method according to claim 16, wherein the first and second splitters are optimized over the respective first and second frequency bands independently of one another. ### Claim 18 (depends on 12) The method according to claim 12, wherein the method comprises modifying a frequency of the RF signal by mixing the sum at the first port with the sum at the second port.