Power amplifier circuit, radio frequency circuit, radio frequency chip and electronic device

Abstract

The application provides a power amplification circuit, a radio frequency circuit, a radio frequency chip and an electronic device. The power amplification circuit comprises a power amplification unit, a signal conversion unit and a resonance unit. The power amplification unit has an input end and an output end, can perform power amplification processing on an input signal input from the input end to form a corresponding amplified signal, and outputs the amplified signal through the output end. The input signal is a differential signal comprising a first frequency band local oscillator signal, and the amplified signal is a differential signal comprising a second frequency band interference signal and the first frequency band local oscillator signal. The signal conversion unit is connected with the output end of the power amplification unit, and the signal conversion unit is used for converting the amplified signal from the differential signal into a single-ended signal. The resonance unit is connected with the signal conversion unit and is connected between the signal conversion unit and the output end of the power amplification circuit.

Description

Technical Field

[0001] This application relates to the field of radio frequency technology, and in particular to a power amplifier circuit, radio frequency circuit, radio frequency chip and electronic device. Background Technology

[0002] Power amplifiers are key components in electronic devices used to enhance signal strength. Their main function is to boost the power of the input signal to a higher level in order to drive loads such as speakers or antennas. They are widely used in communication systems, audio equipment, radar, and wireless transmission systems.

[0003] Because the transmission characteristics of a power amplifier are non-linear, the signal will exhibit third harmonic distortion after being amplified by the power amplifier, affecting the signal transmission quality. Utility Model Content

[0004] This application provides a power amplifier circuit, a radio frequency circuit, a radio frequency chip, and an electronic device.

[0005] The first aspect of this application provides a power amplifier circuit, including a power amplifier unit, a signal conversion unit, and a resonant unit;

[0006] The power amplification unit has an input terminal and an output terminal. The power amplification unit can amplify the input signal input from the input terminal to form an amplified signal corresponding to the input signal, and output the amplified signal through the output terminal. The input signal is a differential signal including a first frequency band local oscillator signal, and the amplified signal is a differential signal including a second frequency band interference signal and the first frequency band local oscillator signal. The second frequency band interference signal is three times the strength of the first frequency band local oscillator signal.

[0007] The signal conversion unit is connected to the output terminal of the power amplification unit, and the signal conversion unit is used to convert the amplified signal from a differential signal into a single-ended signal.

[0008] The resonant unit is connected to the signal conversion unit and is located between the signal conversion unit and the output terminal of the power amplifier circuit; the resonant unit is used to suppress the second frequency band interference signal.

[0009] In one embodiment, when the frequency of the second band interference signal is three times the frequency of the first band local oscillator signal, the resonant frequency is configured to be three times the frequency of the first band local oscillator signal.

[0010] In one embodiment, the resonant unit includes a capacitor unit and an inductor unit; the capacitor unit includes a first terminal and a second terminal, and the inductor unit includes a first terminal and a second terminal; the first terminal of the capacitor unit is connected between the signal conversion unit and the output terminal of the power amplifier circuit, the second terminal of the capacitor unit is connected to the first terminal of the inductor unit, and the second terminal of the inductor unit is grounded.

[0011] In one embodiment, the capacitance of the capacitor unit is adjustable.

[0012] In one embodiment, the capacitor unit includes multiple sub-units connected in parallel, each sub-unit including a capacitor and a switch connected in series with the capacitor, one end of each sub-unit being connected between the signal conversion unit and the output terminal of the power amplifier circuit, and the other end of each sub-unit being connected to the inductor unit.

[0013] In one embodiment, the signal conversion unit includes a primary coil and a secondary coil. The primary coil is connected to the output terminal of the power amplification unit, and one end of the secondary coil is connected to the output terminal of the power amplification circuit, while the other end is grounded.

[0014] The first end of the capacitor unit is connected between the secondary coil and the output end of the power amplifier circuit.

[0015] A second aspect of this application provides a radio frequency (RF) circuit, the RF circuit including the power amplifier circuit described above; the RF circuit further includes: a first amplification unit, a first filtering unit and a first mixing unit, as well as a second amplification unit, a second filtering unit and a second mixing unit;

[0016] The output terminal of the first amplification unit is connected to the input terminal of the first filtering unit; the output terminal of the first filtering unit is connected to the input terminal of the first mixer unit; the output terminal of the first mixer unit is connected to the input terminal of the power amplification unit.

[0017] The output terminal of the second amplification unit is connected to the input terminal of the second filtering unit, and the output terminal of the second filtering unit is connected to the input terminal of the second mixer unit; the output terminal of the second mixer unit is connected to the input terminal of the power amplification unit.

[0018] In one embodiment, the first amplification unit includes a first amplifier, which includes two input terminals and two output terminals; the second amplification unit includes a second amplifier, which includes two input terminals and two output terminals.

[0019] The first filtering unit includes a first RC filter and a second RC filter; the input terminal of the first RC filter is connected to one of the output terminals of the first amplifier, and the input terminal of the second RC filter is connected to the other output terminal of the first amplifier.

[0020] The second filtering unit includes a third RC filter and a fourth RC filter; the input terminal of the third RC filter is connected to one of the output terminals of the second amplifier, and the input terminal of the fourth RC filter is connected to the other output terminal of the second amplifier.

[0021] In one embodiment, the first mixing unit includes a first mixer and a second mixer; the input terminal of the first mixer is connected to the output terminal of the first RC filter; the input terminal of the second mixer is connected to the output terminal of the second RC filter.

[0022] The second mixing unit includes a third mixer and a fourth mixer; the input terminal of the third mixer is connected to the output terminal of the third RC filter; the input terminal of the fourth mixer is connected to the output terminal of the fourth RC filter.

[0023] In one embodiment, the radio frequency circuit further includes a notch filter unit; the notch filter unit includes a first sub-notch filter unit and a second sub-notch filter unit; the first sub-notch filter unit includes a first inductor unit and a first capacitor unit connected in parallel, the resonant frequency of the first inductor unit and the first capacitor unit being three times the frequency of the local oscillator signal in the first frequency band; the second sub-notch filter unit includes a second inductor unit and a second capacitor unit connected in parallel, the resonant frequency of the second inductor unit and the second capacitor unit being three times the frequency of the local oscillator signal in the first frequency band;

[0024] The output terminals of the first mixing unit and the second mixing unit are connected to the input terminal of the power amplifier unit through the first sub-notch filter unit; the output terminals of the first mixing unit and the second mixing unit are connected to the input terminal of the power amplifier unit through the second sub-notch filter unit.

[0025] A third aspect of this application provides a radio frequency chip, including the power amplifier circuit described above, or including the radio frequency circuit described above.

[0026] In one embodiment, the radio frequency chip includes a substrate; when the resonant unit of the power amplifier circuit includes the capacitor unit and the inductor unit, the orthographic projection of the inductor unit on the substrate overlaps with the orthographic projection of the capacitor unit on the substrate.

[0027] A fourth aspect of this application provides an electronic device comprising the radio frequency chip described above.

[0028] The power amplifier circuit provided in this application embodiment can effectively suppress interference signals in the second frequency band, thereby improving the signal transmission quality and transmission efficiency.

[0029] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0031] Figure 1 A schematic block diagram of a power amplifier circuit provided in an embodiment of this application;

[0032] Figure 2 A schematic diagram of the circuit structure of a power amplifier circuit provided in an embodiment of this application;

[0033] Figure 3 A schematic diagram of the circuit structure of a resonant unit provided in an embodiment of this application;

[0034] Figure 4 A schematic structural block diagram of a radio frequency circuit provided in an embodiment of this application;

[0035] Figure 5 This is a schematic diagram of the circuit structure of a radio frequency circuit provided in an embodiment of this application. Detailed Implementation

[0036] The technical solutions in the embodiments (or "implementations") of this application will be clearly and completely described herein with reference to the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0037] If the embodiments of this application contain terms relating to directional indications or positional relationships (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationships and movements between components in a specific posture (as shown in the attached figures); if the specific posture changes, the directional indications or positional relationships will also change accordingly. Furthermore, the terms "first" and "second" used in the embodiments of this application are only for descriptive convenience and should not be construed as indicating or implying relative importance.

[0038] The power amplifier circuit, radio frequency circuit, radio frequency chip, and electronic device according to embodiments of this application will be described in detail below with reference to the accompanying drawings. Unless otherwise specified, the features of the following embodiments and implementation methods can complement or combine with each other.

[0039] This application provides a power amplifier circuit, such as... Figure 1 and Figure 2 As shown, the power amplifier circuit 100 includes a power amplifier unit 10, a signal conversion unit 11, a resonant unit 12, and an input terminal IN and an output terminal OUT.

[0040] The power amplifier unit 10 has an input terminal in and an output terminal out. The input terminal in of the power amplifier unit 10 can be used as the input terminal IN of the power amplifier circuit 100. The power amplifier unit 10 can amplify the input signal input from the input terminal in to form an amplified signal corresponding to the input signal, and output the amplified signal through the output terminal out. The input signal is a differential signal including the local oscillator signal of the first frequency band, and the amplified signal is a differential signal including the interference signal of the second frequency band and the local oscillator signal of the first frequency band. The input signal to the input terminal in is in the form of a differential signal, which can suppress the generation of even harmonics and eliminate common-mode interference in the power amplifier circuit.

[0041] The signal conversion unit 11 is connected to the output terminal of the power amplification unit 10. The signal conversion unit 11 is used to convert the amplified signal from a differential signal into a single-ended signal.

[0042] The resonant unit 12 is connected to the signal conversion unit 11 and is connected between the signal conversion unit 11 and the output terminal OUT of the power amplifier circuit. The resonant unit 12 is used to suppress the second frequency band interference signal.

[0043] The power amplifier circuit 100 of this application can be used as a driver amplifier or a final stage amplifier in a signal transmission system. The input signal to the power amplifier circuit 100 can be the signal obtained by mixing the base frequency signal BB and the first frequency band local oscillator signal LO through a mixer. Since the transmission characteristics of the power amplifier unit 10 are non-linear, the input signal will generate a second frequency band interference signal after being amplified by the power amplifier unit 10. Because the frequency of the base frequency signal BB is much lower than the frequency of the first frequency band local oscillator signal LO (e.g., the base frequency signal BB is between 0 and tens of MHz, while the frequency of the first frequency band local oscillator signal LO is between 1 and tens of GHz), the interference signal generated by the base frequency signal BB has a small impact and can be basically ignored. However, the second frequency band interference signal generated by the first frequency band local oscillator signal LO will cause signal distortion, reducing signal clarity and reliability. The resonant unit 12 in this application can effectively suppress the second frequency band interference signal, thereby improving the signal transmission quality and transmission efficiency.

[0044] In one embodiment, when the frequency of the second-band interference signal is three times the frequency of the first-band local oscillator signal, the resonant frequency of the resonant unit is configured to be three times the frequency of the first-band local oscillator signal. The second-band interference signal generated after the input signal is amplified by the power amplifier unit 10 is a third harmonic, that is, it will generate the third harmonic 3BB of the fundamental frequency signal BB and the third harmonic 3LO of the first-band local oscillator signal LO. The third harmonic 3BB of the fundamental frequency signal BB has a small impact and can be ignored, but the third harmonic 3LO generated by the first-band local oscillator signal LO will cause signal distortion. When the resonant frequency of the resonant unit 12 is set to three times the frequency of the first-band local oscillator signal LO, the resonant unit 12 can effectively suppress the third harmonic 3LO of the first-band local oscillator signal LO.

[0045] It should be noted that the second frequency band interference signal that this application focuses on is the third harmonic of the first frequency band local oscillator signal. For ease of description, "local oscillator signal" in the following text refers to the aforementioned "first frequency band local oscillator signal", and "third harmonic" refers to the aforementioned "second frequency band interference signal".

[0046] In one embodiment, such as Figure 2 As shown, the power amplifier unit 10 includes a power amplifier amp, which has two input terminals in1 and in2 and two output terminals out1 and out2. The two input terminals in1 and in2 of the power amplifier amp serve as the input terminals IN1 and IN2 of the power amplifier circuit 100, respectively. The input signal containing the fundamental frequency signal BB and the local oscillator signal LO can be input as a differential signal through the two input terminals in1 and in2 of the power amplifier amp. After being amplified by the power amplifier amp, it is output through the two output terminals out1 and out2 of the power amplifier amp.

[0047] In one embodiment, the signal conversion unit 11 includes a balun T, which comprises a primary coil t1 and a secondary coil t2. The primary coil t1 is connected to the output terminal OUT of the power amplifier unit 10, meaning that both ends of the primary coil are connected to the two output terminals OUT1 and OUT2 of the power amplifier AMP, respectively. One end of the secondary coil t2 is connected to the output terminal OUT of the power amplifier circuit, and the other end is grounded, i.e., connected to the ground terminal GND. The balun T can convert a differential signal into a single-ended signal and output the single-ended signal as the output signal through the output terminal OUT. In some embodiments, the midpoint of the primary coil t1 is connected to the power supply voltage VCC, providing DC bias through the power supply voltage VCC.

[0048] In one embodiment, the resonant unit 12 includes a capacitor unit C and an inductor unit L. The capacitor unit C includes a first terminal and a second terminal, and the inductor unit L also includes a first terminal and a second terminal. The first terminal of the capacitor unit C is connected between the signal conversion unit 11 and the output terminal OUT of the power amplifier circuit, that is, between the secondary coil t2 and the output terminal OUT of the power amplifier circuit. The second terminal of the capacitor unit C is connected to the first terminal of the inductor unit L, and the second terminal of the inductor unit L is grounded, that is, connected to the ground terminal GND.

[0049] The capacitor unit C and the inductor unit L are connected in series, and the resonant frequency of the capacitor unit C and the inductor unit L is three times the frequency of the local oscillator signal LO. Therefore, the capacitor unit C and the inductor unit L present a low impedance to the third harmonic 3LO of the local oscillator signal LO, which can guide the third harmonic 3LO to the ground terminal GND, thereby suppressing the influence of the third harmonic 3LO and improving the signal transmission performance of the power amplifier circuit 100.

[0050] In one embodiment, the capacitance of capacitor unit C is adjustable. By adjusting the capacitance value of capacitor unit C, the resonant frequency of capacitor unit C and inductor unit L can be adjusted so that the resonant frequency of the resonant unit is three times the frequency of the local oscillator signal.

[0051] In one embodiment, such as Figure 3 As shown, capacitor unit C includes multiple sub-units connected in parallel. Each sub-unit includes a capacitor and a switch connected in series with the capacitor. One end of each sub-unit is connected between the secondary coil and the output terminal of the power amplifier circuit, and the other end of each sub-unit is connected to inductor unit L. By adjusting the switches in each sub-unit, the capacitance value of capacitor unit C can be adjusted, thereby facilitating the setting of the resonant frequency of capacitor unit C and inductor unit L to three times the frequency of the local oscillator signal LO.

[0052] Specifically, such as Figure 3 As shown, capacitor unit C includes subunit C. <1> ~C <n>Subunit C <1> Includes capacitor C1 and switch SW1. One end of capacitor C1 is connected to node N1, and the other end is connected to one end of switch SW1. The other end of switch SW1 is connected to node N2; subunit C <2> Includes capacitor C2 and switch SW2. One end of capacitor C2 is connected to node N1, and the other end is connected to one end of switch SW2. The other end of switch SW2 is connected to node N2; ...; Subunit C <n>This includes a capacitor Cn and a switch SWn. One end of the capacitor Cn is connected to node N1, and the other end is connected to one end of the switch SWn. The other end of the switch SWn is connected to node N2. Each sub-unit of the capacitor unit is connected between the secondary coil and the output terminal OUT through node N1, and is connected to the inductor unit L through node N2.

[0053] In some of his embodiments, the resonant unit 12 can also be other types of circuit structures, as long as the resonant frequency of the resonant unit is three times the frequency of the local oscillator signal.

[0054] This application also provides a radio frequency circuit, such as... Figure 4 and Figure 5 As shown, the radio frequency circuit includes the power amplifier circuit 100 described above.

[0055] The radio frequency circuit also includes a first amplification unit 200, a first filtering unit 300 and a first mixing unit 400, as well as a second amplification unit 500, a second filtering unit 600 and a second mixing unit 700.

[0056] The radio frequency circuit includes input terminals BBI and BBQ. The base frequency signal BB is input to the radio frequency circuit as an input signal. The in-phase component I of the base frequency signal BB is input to the first amplification unit 200 through the input terminal BBI, and the quadrature component Q of the base frequency signal BB is input to the second amplification unit 500 through the input terminal BBQ.

[0057] The output of the first amplification unit 200 is connected to the input of the first filter unit 300. The output of the first filter unit 300 is connected to the input of the first mixer unit 400. The output of the first mixer unit 400 is connected to the input of the power amplifier unit 10. The output of the second amplification unit 500 is connected to the input of the second filter unit 600. The output of the second filter unit 600 is connected to the input of the second mixer unit 700. The output of the second mixer unit 700 is connected to the input of the power amplifier unit 10.

[0058] The fundamental frequency signal BB typically has a low initial amplitude. The first amplification unit 200 and the second amplification unit 500 can initially amplify the fundamental frequency signal BB to meet the input requirements of subsequent circuits. After amplification, spurious waves may be introduced into the signal. The first filtering unit 300 and the second filtering unit 600 can filter out these spurious waves, ensuring the purity of the signal input to the first mixing unit 400 and the second mixing unit 700. The first mixing unit 400 and the second mixing unit 700 mix the fundamental frequency signal BB with the local oscillator signal LO to achieve frequency conversion. The mixed signal is then sent to the power amplifier circuit 100 to amplify the signal to a sufficient power level to meet the needs of subsequent signal transmission. The power amplifier circuit 100 can suppress the third harmonic 3LO of the local oscillator signal LO, thereby reducing harmonic interference caused by the amplifier's nonlinear characteristics and improving signal transmission quality.

[0059] In one embodiment, the first amplification unit 200 includes a first amplifier 21, which has two input terminals and two output terminals. The second amplification unit 500 includes a second amplifier 51, which also has two input terminals and two output terminals. The first filtering unit 300 includes a first RC filter 31 and a second RC filter 32, with the input terminal of the first RC filter 31 connected to one output terminal of the first amplifier 21, and the input terminal of the second RC filter 32 connected to the other output terminal of the first amplifier 21. The second filtering unit 600 includes a third RC filter 61 and a fourth RC filter 62, with the input terminal of the third RC filter 61 connected to one output terminal of the second amplifier 51, and the input terminal of the fourth RC filter 62 connected to the other output terminal of the second amplifier 51.

[0060] When the in-phase component I of the baseband signal BB is input to the RF circuit in differential form, it includes I+ and I-. I+ is input to the first amplifier 21 through the input terminal BBI1 of the first amplifier 21 for amplification, and then enters the first RC filter 31 for noise filtering. I- is input to the first amplifier 21 through the input terminal BBI2 of the first amplifier 21 for amplification, and then enters the second RC filter 32 for noise filtering.

[0061] When the quadrature component Q of the baseband signal BB is input to the RF circuit in differential form, it includes Q+ and Q-. Q+ is amplified by inputting to the second amplifier 51 through the input terminal BBQ1 and then enters the third RC filter 61 for noise filtering. Q- is amplified by inputting to the second amplifier 51 through the input terminal BBQ2 and then enters the fourth RC filter 62 for noise filtering.

[0062] In one embodiment, the first mixing unit 400 includes a first mixer 41 and a second mixer 42. The input terminal of the first mixer 41 is connected to the output terminal of the first RC filter 31, and the I+ output from the first RC filter 31 enters the first mixer 41 to be mixed with the local oscillator signal LO; the input terminal of the second mixer 42 is connected to the output terminal of the second RC filter 32, and the I- output from the second RC filter 32 enters the second mixer 42 to be mixed with the local oscillator signal LOI.

[0063] The second mixing unit 700 includes a third mixer 71 and a fourth mixer 72. The input terminal of the third mixer 71 is connected to the output terminal of the third RC filter 61, and the Q+ output from the third RC filter 61 enters the third mixer 71 to be mixed with the local oscillator signal LOQ. The input terminal of the fourth mixer 72 is connected to the output terminal of the fourth RC filter 62, and the Q- output from the fourth RC filter 62 enters the fourth mixer 72 to be mixed with the local oscillator signal LOQ.

[0064] In one embodiment, the first mixer 41 includes a first transistor T1 and a second transistor T2. The drain of the first transistor T1 is connected to the drain of the second transistor T2 and is also connected to the output of the first RC filter 31. The gates of the first transistor T1 and the second transistor T2 are respectively connected to the local oscillator signal. Specifically, the gate of the first transistor T1 is connected to the local oscillator differential signal LOIP, and the gate of the second transistor T2 is connected to the local oscillator differential signal LOIN.

[0065] The second mixer 42 includes a third transistor T3 and a fourth transistor T4. The drain of the third transistor T3 is connected to the drain of the fourth transistor T4 and is also connected to the output of the second RC filter 32. The gates of the third transistor T3 and the fourth transistor T4 are respectively connected to the local oscillator signal. Specifically, the gate of the third transistor T3 is connected to the local oscillator differential signal LOIP, and the gate of the fourth transistor T4 is connected to the local oscillator differential signal LOIN.

[0066] The third mixer 71 includes a fifth transistor T5 and a sixth transistor T6. The drain of the fifth transistor T5 is connected to the drain of the sixth transistor T6 and is also connected to the output of the third RC filter 61. The gates of the fifth transistor T5 and the sixth transistor T6 are respectively connected to the local oscillator signal. Specifically, the gate of the fifth transistor T5 is connected to the local oscillator differential signal LOQP, and the gate of the sixth transistor T6 is connected to the local oscillator differential signal LOQN.

[0067] The fourth mixer 72 includes a seventh transistor T7 and an eighth transistor T8. The drain of the seventh transistor T7 is connected to the drain of the eighth transistor T8 and is also connected to the output of the fourth RC filter 62. The gates of the seventh transistor T7 and the eighth transistor T8 are respectively connected to the local oscillator signal. Specifically, the gate of the seventh transistor T7 is connected to the local oscillator differential signal LOQP, and the gate of the eighth transistor T8 is connected to the local oscillator differential signal LOQN.

[0068] In one embodiment, the sources of the first transistor T1, the fourth transistor T4, the fifth transistor T5, and the eighth transistor T8 are connected to node N3, and are also connected to the input terminal IN1 of the power amplifier amp through node N3. The in-phase component I and the local oscillator signal LOI are input to the power amplifier circuit 100 through node N3. The sources of the second transistor T2, the third transistor T3, the sixth transistor T6, and the seventh transistor T7 are connected to node N4, and are also connected to the input terminal IN2 of the power amplifier amp. The quadrature component Q and the local oscillator signal LOQ are input to the power amplifier circuit 100 through node N4.

[0069] In the above embodiments, the first transistor T1 to the eighth transistor T8 are all N-type transistors. In other embodiments, the first transistor T1 to the eighth transistor T8 can be P-type transistors. The connection relationship when the first transistor T1 to the eighth transistor T8 are P-type transistors will not be described again here.

[0070] In one embodiment, the radio frequency circuit further includes a notch filter unit 800, which includes a first sub-notch filter unit 81 and a second sub-notch filter unit 82. The first sub-notch filter unit 81 includes a first inductor unit L1 and a first capacitor unit C81 connected in parallel, and the resonant frequency of the first inductor unit L1 and the first capacitor unit C81 is three times the frequency of the local oscillator signal. The second sub-notch filter unit 82 includes a second inductor unit L2 and a second capacitor unit C82 connected in parallel, and the resonant frequency of the second inductor unit L2 and the second capacitor unit C82 is three times the frequency of the local oscillator signal. The output terminals of the first mixer unit 400 and the second mixer unit 700 are connected to the input terminal IN1 of the power amplifier unit 10 through the first sub-notch filter unit 81, and the output terminals of the first mixer unit 400 and the second mixer unit 700 are connected to the input terminal IN2 of the power amplifier unit 10 through the second sub-notch filter unit 82. The first sub-notch filter unit 81 and the second sub-notch filter unit 82 present high impedance to the third harmonic of the local oscillator signal LO, which can effectively suppress the third harmonic 3LO, thus improving the signal transmission quality and efficiency.

[0071] Specifically, the first sub-notch filter unit 81 is connected to node N3, and the in-phase component I and the local oscillator signal LOI are input to the first sub-notch filter unit 81 through node N3. The second sub-notch filter unit 82 is connected to node N4, and the quadrature component Q and the local oscillator signal LOQ are input to the second sub-notch filter unit 82 through node N4.

[0072] In one embodiment, the capacitance of the first capacitor unit C81 and the second capacitor unit C82 is adjustable. By adjusting the capacitance value, the resonant frequency of the first sub-notch filter unit 81 and the second sub-notch filter unit 82 can be adjusted to three times the frequency of the third harmonic 3LO.

[0073] This application also provides an RF chip, which includes the power amplifier circuit described above, or the RF chip includes the RF circuit described above.

[0074] In one embodiment, the radio frequency chip further includes a substrate, such as... Figure 3 As shown, when the resonant unit of the power amplifier circuit includes a capacitor unit C and an inductor unit L, the orthogonal projection of the inductor unit L onto the substrate overlaps with the orthogonal projection of the capacitor unit C onto the substrate. This arrangement avoids increasing the area of ​​the RF chip.

[0075] This application also provides an electronic device, which includes the radio frequency chip described above. The electronic device may be, for example, a smartphone, a base station, a wireless router, a radar system, etc.

[0076] It should be noted that the technical solutions or features described in the above embodiments can be combined or supplemented with each other without conflict. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the accompanying drawings; all modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.< / n> < / n>

Claims

1. A power amplifier circuit, characterized in that, The power amplifier circuit includes a power amplification unit, a signal conversion unit, and a resonant unit; The power amplification unit has an input terminal and an output terminal. The power amplification unit can amplify the input signal input from the input terminal to form an amplified signal corresponding to the input signal, and output the amplified signal through the output terminal. The input signal is a differential signal including a first frequency band local oscillator signal, and the amplified signal is a differential signal including a second frequency band interference signal and the first frequency band local oscillator signal. The signal conversion unit is connected to the output terminal of the power amplification unit, and the signal conversion unit is used to convert the amplified signal from a differential signal into a single-ended signal. The resonant unit is connected to the signal conversion unit and is located between the signal conversion unit and the output terminal of the power amplifier circuit; the resonant unit is used to suppress the second frequency band interference signal.

2. The power amplifier circuit according to claim 1, characterized in that, When the frequency of the interference signal in the second frequency band is three times the frequency of the local oscillator signal in the first frequency band, the resonant frequency of the resonant unit is configured to be three times the frequency of the local oscillator signal in the first frequency band.

3. The power amplifier circuit according to claim 1, characterized in that, The resonant unit includes a capacitor unit and an inductor unit; the capacitor unit includes a first terminal and a second terminal, and the inductor unit includes a first terminal and a second terminal; the first terminal of the capacitor unit is connected between the signal conversion unit and the output terminal of the power amplifier circuit, the second terminal of the capacitor unit is connected to the first terminal of the inductor unit, and the second terminal of the inductor unit is grounded.

4. The power amplifier circuit according to claim 3, characterized in that, The capacitance of the capacitor unit is adjustable.

5. The power amplifier circuit according to claim 4, characterized in that, The capacitor unit includes multiple sub-units connected in parallel. Each sub-unit includes a capacitor and a switch connected in series with the capacitor. One end of each sub-unit is connected between the signal conversion unit and the output terminal of the power amplifier circuit, and the other end of each sub-unit is connected to the inductor unit.

6. The power amplifier circuit as described in claim 3, characterized in that, The signal conversion unit includes a primary coil and a secondary coil. The primary coil is connected to the output terminal of the power amplifier unit, and one end of the secondary coil is connected to the output terminal of the power amplifier circuit, while the other end is grounded. The first end of the capacitor unit is connected between the secondary coil and the output end of the power amplifier circuit.

7. A radio frequency circuit, characterized in that, The radio frequency circuit includes the power amplifier circuit according to any one of claims 1 to 6; the radio frequency circuit further includes: a first amplification unit, a first filtering unit and a first mixing unit, as well as a second amplification unit, a second filtering unit and a second mixing unit; The output terminal of the first amplification unit is connected to the input terminal of the first filtering unit; the output terminal of the first filtering unit is connected to the input terminal of the first mixer unit; the output terminal of the first mixer unit is connected to the input terminal of the power amplification unit. The output terminal of the second amplification unit is connected to the input terminal of the second filtering unit, and the output terminal of the second filtering unit is connected to the input terminal of the second mixer unit; the output terminal of the second mixer unit is connected to the input terminal of the power amplification unit.

8. The radio frequency circuit according to claim 7, characterized in that, The first amplification unit includes a first amplifier, which has two input terminals and two output terminals; the second amplification unit includes a second amplifier, which has two input terminals and two output terminals. The first filtering unit includes a first RC filter and a second RC filter; the input terminal of the first RC filter is connected to one of the output terminals of the first amplifier, and the input terminal of the second RC filter is connected to the other output terminal of the first amplifier. The second filtering unit includes a third RC filter and a fourth RC filter; the input terminal of the third RC filter is connected to one of the output terminals of the second amplifier, and the input terminal of the fourth RC filter is connected to the other output terminal of the second amplifier.

9. The radio frequency circuit according to claim 8, characterized in that, The first mixing unit includes a first mixer and a second mixer; the input terminal of the first mixer is connected to the output terminal of the first RC filter; the input terminal of the second mixer is connected to the output terminal of the second RC filter. The second mixing unit includes a third mixer and a fourth mixer; the input terminal of the third mixer is connected to the output terminal of the third RC filter; the input terminal of the fourth mixer is connected to the output terminal of the fourth RC filter.

10. The radio frequency circuit according to claim 7, characterized in that, The radio frequency circuit further includes a notch filter unit; the notch filter unit includes a first sub-notch filter unit and a second sub-notch filter unit; the first sub-notch filter unit includes a first inductor unit and a first capacitor unit connected in parallel, the resonant frequency of the first inductor unit and the first capacitor unit being three times the frequency of the local oscillator signal in the first frequency band; the second sub-notch filter unit includes a second inductor unit and a second capacitor unit connected in parallel, the resonant frequency of the second inductor unit and the second capacitor unit being three times the frequency of the local oscillator signal in the first frequency band; The output terminals of the first mixing unit and the second mixing unit are connected to the input terminal of the power amplifier unit through the first sub-notch filter unit; the output terminals of the first mixing unit and the second mixing unit are connected to the input terminal of the power amplifier unit through the second sub-notch filter unit.

11. A radio frequency chip, characterized in that, The radio frequency chip includes the power amplifier circuit according to any one of claims 1 to 6, or includes the radio frequency circuit according to any one of claims 7 to 10.

12. The radio frequency chip according to claim 11, characterized in that, The radio frequency chip includes a substrate; when the resonant unit of the power amplifier circuit includes the capacitor unit and the inductor unit, the orthographic projection of the inductor unit on the substrate overlaps with the orthographic projection of the capacitor unit on the substrate.

13. An electronic device, characterized in that, The electronic device includes the radio frequency chip as described in claim 11 or claim 12.

Images