Push-pull power amplifier circuit

Abstract

The present invention discloses a push-pull power amplifier circuit, including a differential amplifier circuit, a first balun, a first output matching circuit and a second output matching circuit. The secondary winding of the first balun includes a first secondary coil segment and a second secondary coil segment; the first end of the primary winding is connected to the output end of the first power amplifier, and the second end of the primary winding is connected to the output end of the second power amplifier; the first end of the first secondary coil segment is connected to the first output matching circuit, and the second end of the first secondary coil segment is grounded; the first end of the second secondary coil segment is connected to the second output matching circuit, and the second end of the second secondary coil segment is grounded; when the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit outputs a first radio frequency output signal; when the working mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit outputs a second radio frequency output signal. This technical solution can optimize the bandwidth performance of the push-pull power amplifier circuit.

Description

Technical Field

[0001] The present invention relates to the field of radio frequency technology, and in particular to a push-pull power amplifier circuit. Background Art

[0002] The key performance target of the fifth generation mobile communication technology (5G) is to significantly increase the transmission rate compared to 4G. The new 5G technology requires the use of a RF front-end with a higher frequency, a larger operating bandwidth, and a higher-order QAM modulation, which places more stringent requirements on the design of the power amplifier of the RF front-end.

[0003] However, when designing a push-pull power amplifier circuit, in order to meet other performance requirements (such as high frequency or high power and other design requirements or performance indicators) of the push-pull power amplifier circuit, the working bandwidth performance of the push-pull power amplifier circuit is ignored. Therefore, while ensuring the overall performance of the push-pull power amplifier circuit, how to improve the working bandwidth of the push-pull power amplifier circuit has become a problem that needs to be solved urgently. Summary of the invention

[0004] The embodiment of the present invention provides a push-pull power amplifier circuit to solve the problem of poor bandwidth performance of the push-pull power amplifier circuit.

[0005] A push-pull power amplifier circuit includes a differential amplifier circuit, a first balun, a first output matching circuit and a second output matching circuit; the differential amplifier circuit includes a first power amplifier and a second power amplifier; the first balun includes a primary winding and a secondary winding; the secondary winding includes a first secondary coil segment and a second secondary coil segment;

[0006] The first end of the primary winding is connected to the output end of the first power amplifier, and the second end of the primary winding is connected to the output end of the second power amplifier; the first end of the first secondary coil segment is connected to the first output matching circuit, and the second end of the first secondary coil segment is grounded; the first end of the second secondary coil segment is connected to the second output matching circuit, and the second end of the second secondary coil segment is grounded;

[0007] When the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit outputs a first RF output signal; when the working mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit outputs a second RF output signal.

[0008] Furthermore, when the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit and part of the second output matching circuit jointly participate in the output impedance matching of the push-pull power amplifier circuit;

[0009] And / or, when the operation mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit and part of the first output matching circuit jointly participate in the output impedance matching of the push-pull power amplifier circuit.

[0010] Further, the first output matching circuit includes a first switching switch and a first matching network; the first end of the first matching network is connected to the first end of the first secondary coil segment, and the second end of the first matching network is grounded; the third end of the first matching network is connected to the first end of the first switching switch; when the working mode of the push-pull power amplifier circuit is the second mode, the first switching switch is disconnected, and the second output matching circuit and the first matching network jointly participate in the output impedance matching of the push-pull power amplifier circuit;

[0011] And / or, the second output matching circuit includes a second switching switch and a second matching network; the first end of the second matching network is connected to the first end of the second secondary coil segment, the second end of the second matching network is grounded, and the third end of the second matching network is connected to the first end of the second switching switch; when the working mode of the push-pull power amplifier circuit is the first mode, the second switching switch is disconnected, and the first output matching circuit and the second matching network jointly participate in the output impedance matching of the push-pull power amplifier circuit.

[0012] Further, the first matching network includes a second capacitor, a first end of the second capacitor is connected to the first end of the first switch, and a second end of the second capacitor is grounded; the first output matching circuit also includes a fifth capacitor, one end of the fifth capacitor is connected to the second end of the first switch; and a second end of the fifth capacitor is grounded;

[0013] The second matching network includes a fourth capacitor, a first end of the fourth capacitor is connected to the first end of the second switching switch, and a second end of the fourth capacitor is grounded; the second output matching circuit also includes a sixth capacitor, one end of the sixth capacitor is connected to the second end of the second switching switch; the second end of the sixth capacitor is grounded.

[0014] Further, the first matching network also includes a first capacitor, a first end of the first capacitor is connected to the first end of the first secondary coil segment, and a second end of the first capacitor is connected to the first end of the first switching switch and the first end of the first second capacitor; the second matching network also includes a third capacitor, a first end of the third capacitor is connected to the first end of the second secondary coil segment, and a second end of the third capacitor is connected to the first end of the second switching switch and the first end of the fourth capacitor.

[0015] Furthermore, the push-pull power amplifier circuit also includes an adjustment matching circuit; the adjustment matching circuit is arranged between the differential amplifier circuit and the first balun; the adjustment matching circuit is configured to perform impedance matching on the push-pull power amplifier circuit based on the working mode of the push-pull power amplifier circuit.

[0016] Further, the first output matching circuit includes a first switching switch and a first matching network; a first end of the first switching switch is connected to a first end of the first secondary coil segment, and a second end of the first switching switch is connected to the first matching network;

[0017] The second output matching circuit includes a second switching switch and a second matching network; a first end of the second switching switch is connected to a first end of the second secondary coil segment, and a second end of the second switching switch is connected to the second matching network;

[0018] When the working mode of the push-pull power amplifier circuit is the first mode, the first switching switch is turned on and the second switching switch is turned off; when the working mode of the push-pull power amplifier circuit is the second mode, the first switching switch is turned off and the second switching switch is turned on.

[0019] Further, the first matching network includes a first capacitor, a second capacitor and a first inductor; the first end of the first capacitor is connected to the second end of the first switch, the second end of the first capacitor is connected to the first end of the second capacitor and the first end of the first inductor, the second end of the second capacitor is grounded, and the second end of the first inductor is the output node of the first matching network;

[0020] The second matching network includes a third capacitor, a fourth capacitor and a second inductor; the first end of the third capacitor is connected to the second end of the second switch, the second end of the third capacitor is connected to the first end of the fourth capacitor and the first end of the second inductor, the second end of the fourth capacitor is grounded, and the second end of the second inductor is the output node of the second matching network.

[0021] Furthermore, the push-pull power amplifier circuit further includes an adjustable capacitor; the primary winding includes a first primary coil segment and a second primary coil segment;

[0022] The first end of the first primary coil segment is coupled to the output end of the first power amplifier, and the second end of the first primary coil segment is connected to the first end of the adjustable capacitor;

[0023] A first end of the second primary coil segment is coupled to an output end of the second power amplifier, and a second end of the second primary coil segment is connected to a second end of the adjustable capacitor.

[0024] Further, the push-pull power amplifier circuit also includes a first switchable harmonic suppression circuit and a second switchable harmonic suppression circuit;

[0025] A first terminal of the first switchable harmonic suppression circuit is connected to a first input terminal of the first balun, and a second terminal of the first switchable harmonic suppression circuit is grounded;

[0026] A first terminal of the second switchable harmonic suppression circuit is connected to a second input terminal of the first balun, and a second terminal of the second switchable harmonic suppression circuit is grounded;

[0027] The capacitance value presented by the first switchable harmonic suppression circuit and the capacitance value presented by the second switchable harmonic suppression circuit are negatively correlated with the operating frequency band of the push-pull power amplifier circuit.

[0028] Furthermore, when the push-pull power amplifier circuit operates in a first frequency band, a first RF output signal is output through the first output matching circuit; when the push-pull power amplifier circuit operates in a second frequency band, a second RF output signal is output through the second output matching circuit, and the first frequency band is greater than the second frequency band.

[0029] Further, a coupling degree between the primary winding and the first secondary coil segment is smaller than a coupling degree between the primary winding and the second secondary coil segment.

[0030] Furthermore, the first balun is applied on a substrate, the substrate includes a first metal layer and a second metal layer arranged adjacent to each other; the first secondary coil segment is arranged in the first metal layer, and the second secondary coil segment is arranged in the second metal layer; the primary winding of the first balun is coupled with the first secondary coil segment in the same layer, and the primary winding of the first balun is coupled with the second secondary coil segment in upper and lower layers.

[0031] The push-pull power amplifier circuit includes a differential amplifier circuit, a first balun, a first output matching circuit, and a second output matching circuit. The differential amplifier circuit includes a first power amplifier and a second power amplifier. The first balun includes a primary winding and a secondary winding. The secondary winding includes a first secondary coil segment and a second secondary coil segment. The first end of the primary winding is connected to the output end of the first power amplifier, and the second end of the primary winding is connected to the output end of the second power amplifier; the first end of the first secondary coil segment is connected to the first output matching circuit, and the second end of the first secondary coil segment is grounded; the first end of the second secondary coil segment is connected to the second output matching circuit, and the second end of the second secondary coil segment is grounded. In this embodiment, by connecting the first end of the first secondary coil segment to the first output matching circuit, the second end of the first secondary coil segment is grounded, and connecting the first end of the second secondary coil segment to the second output matching circuit, the second end of the second secondary coil segment is grounded, when the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit outputs the first RF output signal, and when the working mode of the push-pull power amplifier circuit is the second mode, the second RF output signal is output through the second output matching circuit, thereby achieving the purpose of switching between different working modes in one push-pull power amplifier circuit, and ensuring the output impedance matching of the push-pull power amplifier circuit in different working modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0033] Figure 1 is a circuit diagram of a push-pull power amplifier circuit in one embodiment of the present invention;

[0034] Figure 2 is another circuit diagram of a push-pull power amplifier circuit in one embodiment of the present invention;

[0035] Figure 3 is another circuit diagram of a push-pull power amplifier circuit in one embodiment of the present invention;

[0036] Figure 4 is another circuit diagram of a push-pull power amplifier circuit in one embodiment of the present invention;

[0037] Figure 5 2 is another circuit diagram of a push-pull power amplifier circuit in one embodiment of the present invention.

[0038] In the figure:

[0039] 10. differential amplifier circuit; 20. first balun; 30. first output matching circuit; 31. first matching network; 40. second output matching circuit; 41. second matching network; 50. adjustment matching circuit; 60. first switchable harmonic suppression circuit; 70. second switchable harmonic suppression circuit. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] It should be understood that the present invention can be implemented in different forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, providing these embodiments will make the disclosure thorough and complete and fully convey the scope of the present invention to those skilled in the art. In the accompanying drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0042] It should be understood that when an element or layer is referred to as being "on, adjacent to, connected to or coupled to other elements or layers, it may be directly on, adjacent to, connected to or coupled to other elements or layers, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on, directly adjacent to, directly connected to or directly coupled to other elements or layers, there may be no intervening elements or layers. It should be understood that, although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present invention, the first element, component, region, layer or part discussed below may be represented as a second element, component, region, layer or part.

[0043] Spatially relative terms such as "under," "beneath," "below," "under," "above," "above," and the like may be used herein for ease of description to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that the spatially relative terms are intended to include different orientations of the device in use and operation in addition to the orientations shown in the figures. For example, if the device in the accompanying drawings is flipped, then the elements or features described as "under other elements" or "under" or "under" will be oriented as "above" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatial descriptors used herein are interpreted accordingly.

[0044] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present invention. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0045] In order to fully understand the present invention, detailed structures and steps will be presented in the following description to illustrate the technical solutions proposed by the present invention. The preferred embodiments of the present invention are described in detail below, but in addition to these detailed descriptions, the present invention may also have other implementations.

[0046] This embodiment provides a push-pull power amplifier circuit, such as Figure 1 As shown, it includes a differential amplifier circuit 10, a first balun 20, a first output matching circuit 30 and a second output matching circuit 40; the differential amplifier circuit 10 includes a first power amplifier M1 and a second power amplifier M2; the first balun 20 includes a primary winding and a secondary winding; the secondary winding includes a first secondary coil segment and a second secondary coil segment; the first end of the primary winding is connected to the output end of the first power amplifier M1, and the second end of the primary winding is connected to the output end of the second power amplifier M2; the first end of the first secondary coil segment is connected to the first output matching circuit 30, and the second end of the first secondary coil segment is grounded; the first end of the second secondary coil segment is connected to the second output matching circuit 40, and the second end of the second secondary coil segment is grounded; when the working mode of the push-pull power amplifier circuit is the first mode, the first RF output signal is output through the first output matching circuit 30; when the working mode of the push-pull power amplifier circuit is the second mode, the second RF output signal is output through the second output matching circuit 40.

[0047] The push-pull power amplifier circuit can work in different working modes. For example, the working mode can be the working frequency band of the push-pull power amplifier circuit, or the power mode of the push-pull power amplifier circuit. For example, when the push-pull power amplifier circuit works in different working frequency bands, the working frequency band can be a high frequency band, a medium frequency band, or a low frequency band. When the push-pull power amplifier circuit works in different power modes, the power mode can be a high power mode (HPM) or a low power mode (LPM).

[0048] Preferably, the working mode in this embodiment is the working frequency band of the push-pull power amplifier circuit. The first mode refers to the first frequency band of the push-pull power amplifier circuit, and the second mode refers to the second frequency band of the push-pull power amplifier circuit. The first frequency band and the second frequency band are different frequency bands, that is, any two frequency bands of the high frequency band, the medium frequency band or the low frequency band.

[0049] In a specific embodiment, the push-pull power amplifier circuit includes a differential amplifier circuit 10, and the differential amplifier circuit 10 is configured to amplify two radio frequency signals of equal magnitude and opposite phases.

[0050] As an example, two RF signals of equal magnitude and opposite phases include a first RF input signal and a second RF input signal. The differential amplifier circuit 10 includes a first power amplifier M1 and a second power amplifier M2. The first power amplifier M1 is configured to amplify the first RF input signal and output a first RF amplified signal, and the second power amplifier M2 is configured to amplify the second RF input signal and output a second RF amplified signal. Optionally, the first power amplifier M1 and the second power amplifier M2 may be BJT transistors (e.g., HBT transistors) or field effect transistors.

[0051] As an example, the first RF input signal and the second RF input signal may be signals output by a front-stage circuit of the differential amplifier circuit 10. Optionally, the front-stage circuit includes a second balun. Exemplarily, the first input end of the second balun is configured to receive the first RF signal, the second input end of the second balun is grounded, the first output end of the second balun is connected to the input end of the first power amplifier M1, the second output end of the second balun is connected to the input end of the second power amplifier M2, and the second balun is configured to convert the first RF signal into a first RF input signal and a second RF input signal, and output the first RF input signal to the first power amplifier M1 so that the first power amplifier M1 amplifies the first RF input signal, and outputs the second RF input signal to the second power amplifier M2 so that the second power amplifier M2 amplifies the second RF input signal.

[0052] In a specific embodiment, the push-pull power amplifier circuit further includes a first balun 20, a first output matching circuit 30, and a second output matching circuit 40. The first balun 20 includes a primary winding and a secondary winding. The secondary winding includes a first secondary coil segment and a second secondary coil segment. The first end of the primary winding is connected to the output end of the first power amplifier M1, and is configured to receive the first RF amplified signal output by the first power amplifier M1. The second end of the primary winding is connected to the output end of the second power amplifier M2, and is configured to receive the second RF amplified signal output by the second power amplifier M2. The first end of the first secondary coil segment is connected to the first output matching circuit 30, and the second end of the first secondary coil segment is grounded. When the working mode of the push-pull power amplifier circuit is the first mode, the primary winding and the first secondary coil segment are coupled to each other, and the first RF amplified signal and the second RF amplified signal are synthesized and converted, and the first RF output signal is output through the first output matching circuit 30. When the working mode of the push-pull power amplifier circuit is the second mode, the primary winding and the second secondary coil segment are coupled to each other, and the first RF amplified signal and the second RF amplified signal are synthesized and converted, and the second RF output signal is output through the second output matching circuit 40. In this embodiment, when the working mode of the push-pull power amplifier circuit is the first mode, the first RF output signal is output through the first output matching circuit 30, and when the working mode of the push-pull power amplifier circuit is the second mode, the second RF output signal is output through the second output matching circuit 40, thereby achieving the purpose of switching between different working modes in a push-pull power amplifier circuit, and ensuring the output impedance matching of the push-pull power amplifier circuit in different working modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

[0053] In a specific embodiment, the first power amplifier M1 is a BJT tube, including a base, a collector and an emitter, the base of the first power amplifier M1 receives an input first RF input signal, the collector of the first power amplifier M1 is connected to the first end of the primary winding, and the emitter of the first power amplifier M1 is grounded; the second power amplifier M2 is a BJT tube, including a base, a collector and an emitter, the base of the second power amplifier M2 receives an input second RF input signal, the collector of the second power amplifier M2 is connected to the second end of the primary winding, and the emitter of the second power amplifier M2 is grounded.

[0054] In this embodiment, the push-pull power amplifier circuit includes a differential amplifier circuit 10, a first balun 20, a first output matching circuit 30 and a second output matching circuit 40. The differential amplifier circuit 10 includes a first power amplifier M1 and a second power amplifier M2. The first balun 20 includes a primary winding and a secondary winding. The secondary winding includes a first secondary coil segment and a second secondary coil segment. The first end of the primary winding is connected to the output end of the first power amplifier M1, and the second end of the primary winding is connected to the output end of the second power amplifier M2; the first end of the first secondary coil segment is connected to the first output matching circuit 30, and the second end of the first secondary coil segment is grounded; the first end of the second secondary coil segment is connected to the second output matching circuit 40, and the second end of the second secondary coil segment is grounded. In this embodiment, by connecting the first end of the first secondary coil segment to the first output matching circuit 30, the second end of the first secondary coil segment is grounded, and connecting the first end of the second secondary coil segment to the second output matching circuit 40, the second end of the second secondary coil segment is grounded, when the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit 30 outputs the first RF output signal, and when the working mode of the push-pull power amplifier circuit is the second mode, the second RF output signal is output through the second output matching circuit 40, thereby achieving the purpose of switching between different working modes in a push-pull power amplifier circuit, and ensuring the output impedance matching of the push-pull power amplifier circuit in different working modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

[0055] In one embodiment, when the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit 30 and part of the second output matching circuit 40 jointly participate in the output impedance matching of the push-pull power amplifier circuit. And / or, when the working mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit 40 and part of the first output matching circuit 30 jointly participate in the output impedance matching of the push-pull power amplifier circuit.

[0056] In a specific embodiment, by connecting the first end of the first secondary coil segment to the first output matching circuit 30, grounding the second end of the first secondary coil segment, connecting the first end of the second secondary coil segment to the second output matching circuit 40, grounding the second end of the second secondary coil segment, connecting certain components (e.g., capacitors) in the first output matching circuit 30 to the ground end, and connecting certain components (e.g., capacitors) in the second output matching circuit 40 to the ground end, when the working mode of the push-pull power amplifier circuit is the first mode, it is ensured that the second secondary coil segment and part of the second output matching circuit 40 can form a ground loop, so that the first output matching circuit 30 and part of the second output matching circuit 40 jointly participate in the output impedance matching of the push-pull power amplifier circuit, so as to facilitate impedance matching of the push-pull power amplifier circuit whose working mode is the first mode. When the working mode of the push-pull power amplifier circuit is the second mode, it is ensured that the first secondary coil segment and part of the first output matching circuit 30 can form a ground loop, so that the second output matching circuit 40 and part of the first output matching circuit 30 jointly participate in the output impedance matching of the push-pull power amplifier circuit, so as to facilitate impedance matching of the push-pull power amplifier circuit whose working mode is the first mode.

[0057] In this embodiment, when the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit 30 and part of the second output matching circuit 40 jointly participate in the output impedance matching of the push-pull power amplifier circuit. And / or, when the working mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit 40 and part of the first output matching circuit 30 jointly participate in the output impedance matching of the push-pull power amplifier circuit, so that when the push-pull power amplifier circuit works in different working modes, the first output matching circuit 30 and the second output matching circuit 40 can jointly participate in the impedance matching, so as to improve the flexibility of output impedance matching in different working modes, and ensure the output impedance matching of the push-pull power amplifier circuit in different working modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

[0058] In one embodiment, if Figure 1 As shown, the first output matching circuit 30 includes a first switching switch S311 and a first matching network 31; the first end of the first matching network 31 is connected to the first end of the first secondary coil segment, and the second end of the first matching network 31 is grounded; the third end of the first matching network 31 is connected to the first end of the first switching switch S311. The second output matching circuit 40 includes a second switching switch S411 and a second matching network 41; the first end of the second matching network 41 is connected to the first end of the second secondary coil segment, the second end of the second matching network 41 is grounded, and the third end of the second matching network 41 is connected to the first end of the second switching switch S411.

[0059] When the working mode of the push-pull power amplifier circuit is the first mode, the first switch S311 is turned on and the second switch S411 is turned off. Since the second matching network 41 is arranged between the second switch S411 and the first end of the second secondary coil segment and is connected to the ground end, when the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit 30 and the second matching network 41 jointly participate in the output impedance matching of the push-pull power amplifier circuit, so as to improve the flexibility of achieving output impedance matching in the first working mode. When the working mode of the push-pull power amplifier circuit is the second mode, the first switch S311 is turned off and the second switch S411 is turned on. Since the first matching network 31 is arranged between the first switch S311 and the first end of the first secondary coil segment and is connected to the ground end, when the working mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit 40 and the first matching network 31 jointly participate in the output impedance matching of the push-pull power amplifier circuit.

[0060] In a specific embodiment, the first output matching circuit 30 includes a first switching switch S311 and a first matching network 31, wherein the first end of the first matching network 31 is connected to the first end of the first secondary coil segment, and the second end of the first matching network 31 is grounded; the first end of the first switching switch S311 is coupled to the first matching network 31, and the second end of the first switching switch S311 is an output node of the first output matching circuit 30, and is configured to output a first RF output signal when the working mode of the push-pull power amplifier circuit is the first mode. The second output matching circuit 40 includes a second switching switch S411 and a second matching network 41; the first end of the second matching network 41 is connected to the first end of the second secondary coil segment, and the second end of the second matching network 41 is grounded, the first end of the second switching switch S411 is coupled to the second matching network 41, and the second end of the second switching switch S411 is an output node of the second output matching circuit 40, and is configured to output a second RF output signal when the working mode of the push-pull power amplifier circuit is the second mode.

[0061] In this embodiment, when the working mode of the push-pull power amplifier circuit is the first mode, for example, when the working frequency band of the push-pull power amplifier circuit is the intermediate frequency band, the first switching switch S311 is turned on and the second switching switch S411 is turned off, so that the second secondary coil segment and the second matching network 41 form a ground loop, and then the first output matching circuit 30 and the second matching network 41 jointly participate in the output impedance matching of the push-pull power amplifier circuit, so as to improve the flexibility of impedance adjustment when the push-pull power amplifier circuit works in the intermediate frequency band mode. When the working mode of the push-pull power amplifier circuit is the second mode, for example, when the working frequency band of the push-pull power amplifier circuit is the high frequency band, the first switching switch S311 is disconnected and the second switching switch S411 is turned on, so that the first secondary coil segment and the first matching network 31 form a ground loop, and then the second output matching circuit 40 and the first matching network 31 jointly participate in the output impedance matching of the push-pull power amplifier circuit, so as to improve the flexibility of impedance adjustment when the push-pull power amplifier circuit works in the high frequency band mode, so as to achieve the purpose of switching between different working modes in one push-pull power amplifier circuit, and can ensure the output impedance matching of the push-pull power amplifier circuit in different working modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

[0062] Optionally, the first matching network 31 and the second matching network 41 are networks formed by a series and / or parallel combination of capacitors and / or inductors.

[0063] Preferably, since the impedance of the first secondary coil segment and the second secondary coil segment in the first balun 20 is inductive, a first matching network 31 and a second matching network 41 formed by capacitors connected in parallel and / or in series are selected. Even if the first matching network 31 and the second matching network 41 are capacitive, it is convenient to adjust the output impedance of the push-pull power amplifier circuit to achieve output impedance matching of the push-pull power amplifier circuit.

[0064] The first matching network 31 includes a second capacitor, a first end of the second capacitor is connected to the first end of the first switching switch, and a second end of the second capacitor is grounded; the second end of the first switching switch is an output node of the first matching network 31; the first output matching circuit 30 also includes a fifth capacitor, one end of the fifth capacitor is connected to the second end of the first switching switch; the fifth capacitor is grounded, and the second capacitor and the fifth capacitor can be connected to different grounds or to the same ground.

[0065] The second matching network 41 includes a fourth capacitor, a first end of the fourth capacitor is connected to the first end of the second switching switch, and a second end of the fourth capacitor is grounded; the second end of the second switching switch is the output node of the second matching network 41; the second output matching circuit 40 also includes a sixth capacitor, one end of the sixth capacitor is connected to the second end of the second switching switch; the sixth capacitor is grounded, and the second capacitor and the fifth capacitor can be connected to different grounds or to the same ground.

[0066] It should be noted that, when the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit 30 mainly plays the role of impedance matching, and at this time, the capacitance value of the capacitor to ground in the second output matching circuit 40 is not easy to be too large. When the working mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit 40 mainly plays the role of impedance matching, and at this time, the capacitance value of the capacitor to ground in the second output matching circuit 40 needs to be relatively large. Similarly, when the working mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit 40 mainly plays the role of impedance matching, and at this time, the capacitance value of the capacitor to ground in the first output matching circuit 30 is not easy to be too large. When the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit 30 mainly plays the role of impedance matching, and at this time, the capacitance value of the capacitor to ground in the first output matching circuit 30 needs to be relatively large.

[0067] In view of this, the present application connects the first end of the second capacitor to the first end of the first switching switch, and the second end of the second capacitor is grounded; the second end of the first switching switch is the output node of the first matching network 31, and one end of the fifth capacitor is connected to the second end of the first switching switch; the second end of the fifth capacitor is connected to the second end of the second capacitor, and the first end of the fourth capacitor is connected to the first end of the second switching switch, the second end of the second switching switch is the output node of the second matching network 41, and one end of the sixth capacitor is connected to the second end of the second switching switch; the second end of the sixth capacitor is connected to the second end of the fourth capacitor. It can be seen that when the working mode of the push-pull power amplifier circuit is the first mode, the first switching switch is closed. At this time, the fifth capacitor and the second capacitor in the first output matching circuit 30 are connected in parallel to form a larger capacitor to ground to participate in impedance matching. Since the second switching switch is disconnected, at this time, only the fourth capacitor in the second output matching circuit 40 forms a smaller capacitor to ground to participate in impedance matching. When the working mode of the push-pull power amplifier circuit is the second mode, the second switching switch is closed. At this time, the sixth capacitor and the fourth capacitor in the second output matching circuit 40 are connected in parallel to form a larger capacitance to ground to participate in impedance matching. Since the first switching switch is disconnected, at this time, only the fourth capacitor in the first output matching circuit 30 forms a smaller capacitance to ground to participate in impedance matching, so that the output impedance of the push-pull power amplifier circuit can be flexibly adjusted to achieve impedance matching.

[0068] In one embodiment, if Figure 1 As shown, the first matching network 31 includes a first capacitor C311 and a second capacitor C312, the first end of the first capacitor C311 is connected to the first end of the first secondary coil segment, the second end of the first capacitor C311 is connected to the first end of the first switching switch S311 and the first end of the second capacitor C312, the second end of the second capacitor C312 is grounded, and the second end of the first switching switch S311 is the output node of the first matching network 31.

[0069] The second matching network 41 includes a third capacitor C411 and a fourth capacitor C412, wherein the first end of the third capacitor C411 is connected to the first end of the second secondary coil segment, the second end of the third capacitor C411 is connected to the first end of the second switching switch S411 and the first end of the fourth capacitor C412, and the second end of the fourth capacitor C412 is grounded; the second end of the second switching switch S411 is the output node of the second matching network 41.

[0070] The first output matching circuit 30 further includes a fifth capacitor C313 , one end of which is connected to the second end of the first switch S311 ; and a second end of the fifth capacitor C313 is connected to the second end of the second capacitor C312 .

[0071] The second output matching circuit 40 further includes a sixth capacitor C413 , one end of which is connected to the second end of the second switch S411 ; and the second end of the sixth capacitor C413 is connected to the second end of the fourth capacitor C412 .

[0072] In a specific embodiment, the first matching network 31 includes a first capacitor C311 and a second capacitor C312. The first end of the first capacitor C311 is connected to the first end of the first secondary coil segment, the second end of the first capacitor C311 is connected to the first end of the first switch S311 and the first end of the second capacitor C312, the second end of the second capacitor C312 is grounded, and the second end of the first switch S311 is the output node of the first matching network 31.

[0073] In a specific embodiment, the second matching network 41 includes a third capacitor C411 and a fourth capacitor C412, the first end of the third capacitor C411 is connected to the first end of the second secondary coil segment, the second end of the third capacitor C411 is connected to the first end of the second switching switch S411 and the first end of the fourth capacitor C412, and the second end of the fourth capacitor C412 is grounded; the second end of the second switching switch S411 is the output node of the second matching network 41.

[0074] In the above circuit structure, when the operating frequency band of the push-pull power amplifier circuit is the first frequency band (for example, the high frequency band), the first switching switch S311 is turned on and the second switching switch S411 is turned off, so that the second secondary coil segment, the third capacitor C411 and the fourth capacitor C412 form a ground loop, and then the first output matching circuit 30 and the second secondary coil segment, the third capacitor C411 and the fourth capacitor C412 jointly participate in the output impedance matching of the push-pull power amplifier circuit. When the working frequency band of the push-pull power amplifier circuit is the second frequency band (for example, the intermediate frequency band), the first switching switch S311 is disconnected and the second switching switch S411 is turned on, so that the first secondary coil segment and the first capacitor C311 and the second capacitor C312 form a grounding loop, and then the second output matching circuit 40 and the second secondary coil segment, the first capacitor C311 and the second capacitor C312 jointly participate in the output impedance matching of the push-pull power amplifier circuit, thereby achieving the purpose of switching between different working modes in one push-pull power amplifier circuit, and ensuring the output impedance matching of the push-pull power amplifier circuit in different working modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

[0075] In a specific embodiment, if Figure 2As shown, the first output matching circuit 30 also includes a fifth capacitor C313, one end of the fifth capacitor C313 is connected to the second end of the first switch S311, and the second end of the fifth capacitor C313 is connected to the second end of the second capacitor C312. The second output matching circuit 40 also includes a sixth capacitor C413, one end of the sixth capacitor C413 is connected to the second end of the second switch S411, and the second end of the sixth capacitor C413 is connected to the second end of the fourth capacitor C412. In this embodiment, when the working frequency band of the push-pull power amplifier circuit is the first frequency band, the first switch S311 is disconnected, the second switch S411 is turned on, and the third capacitor C411, the fourth capacitor C412 and the sixth capacitor C413 in the second output matching circuit 40, as well as the second secondary coil segment, the first capacitor C311 and the second capacitor C312 jointly participate in the output impedance matching of the push-pull power amplifier circuit. When the operating frequency band of the push-pull power amplifier circuit is the second frequency band, the first switching switch S311 is turned on, the second switching switch S411 is turned off, and the first capacitor C311, the second capacitor C312 and the fifth capacitor C313 in the first output matching circuit 30, as well as the second secondary coil segment, the third capacitor C411 and the fourth capacitor C412 jointly participate in the output impedance matching of the push-pull power amplifier circuit.

[0076] In this embodiment, when the working frequency band of the push-pull power amplifier circuit is the first frequency band, the third capacitor C411, the fourth capacitor C412 and the sixth capacitor C413 mainly play the role of impedance matching, and the first capacitor C311 and the second capacitor C312 assist in impedance matching. When the working frequency band of the push-pull power amplifier circuit is the second frequency band, the first capacitor C311, the second capacitor C312 and the fifth capacitor C313 mainly play the role of impedance matching, and the third capacitor C411 and the fourth capacitor C412 play the role of auxiliary adjustment. Therefore, when the operating frequency band of the push-pull power amplifier circuit is the first frequency band, the first switching switch S311 is disconnected, the second switching switch S411 is turned on, the fourth capacitor C412 and the sixth capacitor C413 are connected in parallel to provide a larger capacitance value, and the first capacitor C311 and the second capacitor C312 assist in impedance matching. When the operating frequency band of the push-pull power amplifier circuit is the second frequency band, the first switching switch S311 is turned on, the second switching switch S411 is disconnected, the second capacitor C312 and the fifth capacitor C313 are connected in parallel to provide a larger capacitance value, and the third capacitor C411 and the fourth capacitor C412 assist in impedance matching, so as to more flexibly adjust the output impedance of the push-pull power amplifier circuit.

[0077] In one embodiment, if Figure 3As shown, the push-pull power amplifier circuit also includes an adjustment matching circuit 50; the adjustment matching circuit 50 is arranged between the differential amplifier circuit 10 and the first balun 20; the adjustment matching circuit 50 is configured to perform impedance matching on the push-pull power amplifier circuit based on the working mode of the push-pull power amplifier circuit.

[0078] In a specific embodiment, the adjustment matching circuit 50 is configured to perform impedance matching on the fundamental wave signal of the push-pull power amplifier circuit based on the working frequency band of the push-pull power amplifier circuit.

[0079] In a specific embodiment, the adjustment matching circuit 50 includes a first capacitance adjustment circuit, a first inductance adjustment circuit, and a second inductance adjustment circuit.

[0080] As an example, the first end of the first inductance adjustment circuit is connected to the output end of the first power amplifier M1, the second end of the first inductance adjustment circuit is connected to the first end of the primary winding and the first end of the first capacitance adjustment circuit, and the first inductance adjustment circuit is configured to switch the inductance value based on the working mode of the push-pull power amplifier circuit.

[0081] As an example, the first end of the second inductance adjustment circuit is connected to the output end of the second power amplifier M2, the second end of the second inductance adjustment circuit is connected to the second end of the primary winding and the second end of the second capacitor C312 adjustment circuit, and the second inductance adjustment circuit is configured to switch the inductance value based on the working mode of the push-pull power amplifier circuit.

[0082] As an example, the first capacitance adjustment circuit is configured to switch the capacitance value based on the working mode of the push-pull power amplifier circuit.

[0083] Optionally, the first inductance adjustment circuit includes a first inductor and a third switch connected in parallel; the second inductance adjustment circuit includes a second inductor and a fourth switch connected in parallel; and the first capacitance adjustment circuit includes a seventh capacitance and a fifth switch connected in series.

[0084] In this embodiment, when the working frequency band of the push-pull power amplifier circuit is the first frequency band, the third switch and the fourth switch are turned off, the fifth switch is turned on, the first inductor and the second inductor are connected to the circuit to participate in matching, and the seventh capacitor is connected to the circuit to participate in matching, so as to perform impedance matching on the fundamental signal corresponding to the second frequency band. When the working frequency band of the push-pull power amplifier circuit is the second frequency band, the third switch and the fourth switch are turned on, the fifth switch is turned off, the first inductor and the second inductor are short-circuited, and the seventh capacitor is disconnected, so as to perform impedance matching on the fundamental signal corresponding to the first frequency band. The first frequency band is greater than the second frequency band.

[0085] In a specific embodiment, the adjustment matching circuit 50 further includes a third switchable harmonic suppression circuit. The third switchable harmonic suppression circuit is configured to suppress odd harmonic signals of the push-pull power amplifier circuit.

[0086] Optionally, the odd harmonic signal can be one of a third harmonic signal, a fifth harmonic signal or a seventh harmonic signal. Preferably, among the odd harmonic signals in the push-pull power amplifier circuit, the harmonic component of the third harmonic signal is the largest, and therefore, the odd harmonic signal is preferably a third harmonic signal.

[0087] Optionally, the third switchable harmonic suppression circuit includes a third inductor, an eighth capacitor, a ninth capacitor and a sixth switch; the first end of the third inductor is connected to the output end of the first power amplifier M1 and the first end of the first inductor adjustment circuit, and the second end of the third inductor is connected to the first end of the eighth capacitor and the first end of the sixth switch; the second end of the eighth capacitor is connected to the output end of the second power amplifier M2 and the first end of the second inductor adjustment circuit; the second end of the sixth switch is connected to the first end of the ninth capacitor, and the second end of the ninth capacitor is connected to the second end of the eighth capacitor.

[0088] When the working mode of the push-pull power amplifier circuit is the first mode, the sixth switch is disconnected, and a resonant circuit is formed by the third inductor and the eighth capacitor. When the working mode of the push-pull power amplifier circuit is the second mode, the sixth switch is turned on, the eighth capacitor and the ninth capacitor are connected in parallel, the capacitance value presented by the third switchable harmonic suppression circuit increases, and a resonant circuit is formed by the third inductor and the eighth capacitor and the ninth capacitor connected in parallel, so as to suppress the odd harmonic signals of the push-pull power amplifier circuit. Among them, the first frequency band is greater than the second frequency band.

[0089] According to the resonant frequency formula: , where f is the resonant frequency point of the third switchable harmonic suppression circuit, L is the inductance value, and C is the capacitance value. Since the larger the operating frequency band of the push-pull power amplifier circuit, the larger the odd harmonic signal component of the push-pull power amplifier circuit, the larger the resonant frequency point of the third switchable harmonic suppression circuit is, so as to suppress the odd harmonic signal. Since the inductance value L of the third inductor remains unchanged, the larger the resonant frequency point f of the third switchable harmonic suppression circuit is, the smaller the capacitance value C presented by the third switchable harmonic suppression circuit needs to be. The smaller the resonant frequency point f of the third switchable harmonic suppression circuit is, the larger the capacitance value C presented by the third switchable harmonic suppression circuit needs to be. Therefore, in this embodiment, when the working mode of the push-pull power amplifier circuit is the first mode, the sixth switch is disconnected, and only the eighth capacitor is connected to the circuit to reduce the capacitance value presented by the third switchable harmonic suppression circuit. When the working mode of the push-pull power amplifier circuit is the second mode, the sixth switch is turned on, the eighth capacitor and the ninth capacitor are connected in parallel, and the capacitance value presented by the third switchable harmonic suppression circuit is increased, thereby flexibly adjusting the resonant frequency point of the third switchable harmonic suppression circuit to suppress odd harmonic signals in different working frequency bands and optimize the bandwidth performance of the push-pull power amplifier circuit.

[0090] In one embodiment, the first output matching circuit 30 includes a switch and a switchable network, and the switchable network is a switchable network composed of at least one component of a capacitor, an inductor, and a resistor (not shown in the figure). The first output matching circuit 30 is switched according to the working mode of the push-pull power amplifier circuit to meet the output impedance matching in different working modes, thereby achieving the purpose of switching different working modes in one push-pull power amplifier circuit, and ensuring the output impedance matching of the push-pull power amplifier circuit in different working modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

[0091] In one embodiment, if Figure 4 As shown, the first matching network 31 includes a first capacitor C311, a second capacitor C312 and a first inductor L51; the first end of the first capacitor C311 is connected to the second end of the first switching switch S311, the second end of the first capacitor C311 is connected to the first end of the second capacitor C312 and the first end of the first inductor L51, the second end of the second capacitor C312 is grounded, and the second end of the first inductor L51 is the output node of the first matching network 31; the second matching network 41 includes a third capacitor C411, a fourth capacitor C412 and the second inductor L52; the first end of the third capacitor C411 is connected to the second end of the second switching switch S411, the second end of the third capacitor C411 is connected to the first end of the fourth capacitor C412 and the first end of the second inductor L52, the second end of the fourth capacitor C412 is grounded, and the second end of the second inductor L52 is the output node of the second matching network 41.

[0092] In a specific embodiment, the first matching network 31 includes a first capacitor C311, a second capacitor C312 and a first inductor L51; the first end of the first capacitor C311 is connected to the second end of the first switch S311, the second end of the first capacitor C311 is connected to the first end of the second capacitor C312 and the first end of the first inductor L51, the second end of the second capacitor C312 is grounded, and the second end of the first inductor L51 is the output node of the first matching network 31. In this embodiment, by connecting the first end of the first capacitor C311 to the second end of the first switch S311, the second end of the first capacitor C311 is connected to the first end of the second capacitor C312 and the first end of the first inductor L51, and the second end of the second capacitor C312 is grounded, the first capacitor C311, the second capacitor C312 and the first end of the first inductor L51 can participate in the output impedance matching of the push-pull power amplifier circuit when the working mode of the push-pull power amplifier circuit is the first mode, so as to flexibly adjust the output impedance of the push-pull power amplifier circuit.

[0093] In a specific embodiment, the second matching network 41 includes a third capacitor C411, a fourth capacitor C412, and a second inductor L52; a first end of the third capacitor C411 is connected to a second end of the second switch S411, a second end of the third capacitor C411 is connected to a first end of the fourth capacitor C412 and a first end of the second inductor L52, a second end of the fourth capacitor C412 is grounded, and a second end of the second inductor L52 is an output node of the second matching network 41. In this embodiment, by connecting a first end of the third capacitor C411 to a second end of the second switch S411, a second end of the third capacitor C411 is connected to a first end of the fourth capacitor C412 and a first end of the second inductor L52, and a second end of the fourth capacitor C412 is grounded, the third capacitor C411, the fourth capacitor C412, and the second inductor L52 can participate in the output impedance matching of the push-pull power amplifier circuit when the working mode of the push-pull power amplifier circuit is the first mode, so as to flexibly adjust the output impedance of the push-pull power amplifier circuit.

[0094] In one embodiment, if Figure 5 As shown, the push-pull power amplifier circuit also includes an adjustable capacitor Ct; the primary winding includes a first primary coil segment and a second primary coil segment; the first end of the first primary coil segment is coupled to the output end of the first power amplifier M1, and the second end of the first primary coil segment is connected to the first end of the adjustable capacitor Ct; the first end of the second primary coil segment is coupled to the output end of the second power amplifier M2, and the second end of the second primary coil segment is connected to the second end of the adjustable capacitor Ct.

[0095] In a specific embodiment, the first end of the first primary coil segment is coupled to the output end of the first power amplifier M1, the second end of the first primary coil segment is connected to the first end of the adjustable capacitor Ct, the first end of the second primary coil segment is coupled to the output end of the second power amplifier M2, and the second end of the second primary coil segment is connected to the second end of the adjustable capacitor Ct. In this embodiment, the adjustable capacitor Ct forms a resonant circuit with the first primary coil segment and the second primary coil segment for impedance matching of the push-pull power amplifier circuit.

[0096] In this embodiment, by coupling the first end of the first primary coil segment to the output end of the first power amplifier M1, connecting the second end of the first primary coil segment to the first end of the adjustable capacitor Ct, and coupling the first end of the second primary coil segment to the output end of the second power amplifier M2, the second end of the second primary coil segment is connected to the second end of the adjustable capacitor Ct, so that the capacitance value of the adjustable capacitor Ct can be flexibly adjusted according to the operating frequency band of the push-pull power amplifier circuit, and the push-pull power amplifier circuit can be flexibly impedance matched.

[0097] Optionally, the push-pull power amplifier circuit further includes a first matching inductor L81 and a second matching inductor L82. The first end of the first matching inductor L81 is connected to the output end of the first power amplifier M1, the second end of the first matching inductor L81 is connected to the first end of the first primary coil segment, the first end of the second matching inductor L82 is connected to the output end of the second power amplifier M2, and the second end of the second matching inductor L82 is connected to the first end of the second primary coil segment. The first matching inductor L81 and the second matching inductor L82 are used to participate in the impedance matching of the push-pull power amplifier circuit. In a specific embodiment, the first matching inductor L81 can be implemented through a transmission line between the output end of the first power amplifier M1 and the first end of the first primary coil segment. The second matching inductor L82 can be implemented through a transmission line between the output end of the second power amplifier M2 and the first end of the second primary coil segment.

[0098] Optionally, the push-pull power amplifier circuit also includes a harmonic suppression capacitor C81, a first end of the harmonic suppression capacitor C81 is connected to the output end of the first power amplifier M1, and a second end of the harmonic suppression capacitor C81 is connected to the output end of the second power amplifier M2, and is configured to suppress odd harmonic signals of the push-pull power amplifier circuit.

[0099] In one embodiment, if Figure 5As shown, the push-pull power amplifier circuit also includes a first switchable harmonic suppression circuit 60 and a second switchable harmonic suppression circuit 70; the first end of the first switchable harmonic suppression circuit 60 is connected to the first input end of the first balun 20, and the second end of the first switchable harmonic suppression circuit 60 is grounded; the first end of the second switchable harmonic suppression circuit 70 is connected to the second input end of the first balun 20, and the second end of the second switchable harmonic suppression circuit 70 is grounded; the capacitance value presented by the first switchable harmonic suppression circuit 60 and the capacitance value presented by the second switchable harmonic suppression circuit 70 are negatively correlated with the operating frequency band of the push-pull power amplifier circuit.

[0100] In a specific embodiment, the first end of the first switchable harmonic suppression circuit 60 is connected to the first input end of the first balun 20, and the second end of the first switchable harmonic suppression circuit 60 is grounded, and is configured to suppress even harmonic signals of the push-pull power amplifier circuit.

[0101] Optionally, the even harmonic signal can be one of a second harmonic signal, a fourth harmonic signal or a sixth harmonic signal. Preferably, among the even harmonic signals in the push-pull power amplifier circuit, the harmonic component of the second harmonic signal is the largest, and therefore, the even harmonic signal is preferably a second harmonic signal.

[0102] In a specific embodiment, a first end of the second switchable harmonic suppression circuit 70 is connected to the second input end of the first balun 20, and a second end of the second switchable harmonic suppression circuit 70 is grounded, and is configured to suppress even harmonic signals of the push-pull power amplifier circuit.

[0103] Preferably, the first switchable harmonic suppression circuit 60 and the second switchable harmonic suppression circuit 70 are different so as to suppress different even-order harmonic signals.

[0104] It should be noted that the specific circuit structure and the configuration of the resonant frequency point of the first switchable harmonic suppression circuit 60 and the second switchable harmonic suppression circuit 70 are similar to the specific circuit structure and the configuration of the resonant frequency point of the third switchable harmonic suppression circuit in the above embodiment. For example, Figure 5 C61, C62, L61 and S61 in the first switchable harmonic suppression circuit 60, and C71, C72, L71 and S71 in the second switchable harmonic suppression circuit 70 are not described in detail here.

[0105] In one embodiment, when the push-pull power amplifier circuit operates in a first frequency band, a first RF output signal is output through a first output matching circuit 30; when the push-pull power amplifier circuit operates in a second frequency band, a second RF output signal is output through a second output matching circuit 40, and the first frequency band is greater than the second frequency band.

[0106] In a specific embodiment, when the push-pull power amplifier circuit operates in a high frequency band, a first RF output signal is output through the first output matching circuit 30, and when the push-pull power amplifier circuit operates in a medium frequency band, a second RF output signal is output through the second output matching circuit 40, thereby achieving impedance matching of the push-pull power amplifier circuit in different operating frequency bands, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

[0107] In one embodiment, the coupling degree between the primary winding and the first secondary coil segment is smaller than the coupling degree between the primary winding and the second secondary coil segment.

[0108] In a specific embodiment, when the coupling mode of the primary winding and the first secondary coil segment is the same as the coupling mode of the primary winding and the second secondary coil segment, the coupling degree of the primary winding and the first secondary coil segment is the same as the coupling degree of the primary winding and the second secondary coil segment. However, in actual application, when the coupling mode of the primary winding and the first secondary coil segment is the same as the coupling mode of the primary winding and the second secondary coil segment, that is, when the coupling degree of the primary winding and the first secondary coil segment is the same as the coupling degree of the primary winding and the second secondary coil segment, if radio frequency signals of different frequency bands are converted respectively, the coupling degree presented by the primary winding and the first secondary coil segment is different from the coupling degree presented by the primary winding and the second secondary coil segment. For example, by coupling the primary winding and the first secondary coil segment to convert the radio frequency signal of the high frequency band, the coupling degree is greater than the coupling degree when the primary winding and the second secondary coil segment are coupled to convert the radio frequency signal of the low frequency band, thereby causing the coupling degree of the primary winding and the first secondary coil segment to be unbalanced with the coupling degree of the primary winding and the second secondary coil segment. Therefore, in this embodiment, the coupling degree between the primary winding outputting the first RF output signal and the first secondary coil segment is made smaller than the coupling degree between the primary winding outputting the second RF output signal and the second secondary coil segment, so as to balance the coupling degree between the primary winding and the first secondary coil segment and the coupling degree between the primary winding and the second secondary coil segment under different RF signals.

[0109] In one embodiment, the first balun 20 is applied on a substrate, and the substrate includes a first metal layer and a second metal layer arranged adjacent to each other; the first secondary coil segment is arranged in the first metal layer, and the second secondary coil segment is arranged in the second metal layer; the primary winding of the first balun 20 is coupled with the first secondary coil segment in the same layer, and the primary winding of the first balun 20 is coupled with the second secondary coil segment in upper and lower layers.

[0110] In a specific embodiment, the primary winding is coupled with the first secondary coil segment to convert the first RF signal, the RF signal of the high frequency band, and the primary winding is coupled with the second secondary coil segment to convert the second RF signal, the RF signal of the low frequency band. Therefore, in this embodiment, by setting the first secondary coil segment on the first metal layer and the second secondary coil segment on the second metal layer, the primary winding of the first balun 20 is coupled with the first secondary coil segment on the same layer, and the primary winding of the first balun 20 is coupled with the second secondary coil segment on the upper and lower layers. In this embodiment, since the coupling degree of the same layer coupling is originally smaller than the coupling degree of the upper and lower layer coupling, the primary winding of the first balun 20 is coupled with the first secondary coil segment on the same layer, and the primary winding of the first balun 20 is coupled with the second secondary coil segment on the upper and lower layers, so that the coupling degree of the primary winding outputting the first RF output signal and the first secondary coil segment can be balanced with the coupling degree of the primary winding outputting the second RF output signal and the second secondary coil segment, so as to ensure the balance of the RF output signals outputted at different working frequency bands.

[0111] It should be noted that, in this embodiment, the primary winding of the first balun 20 is coupled with the upper and lower layers of the first secondary coil segment, and the primary winding is coupled with the second secondary coil segment on the same layer as one of the exemplary explanations, including but not limited to any other implementation methods that can change the coupling degree between the primary winding and the first secondary coil segment, and the coupling degree between the primary winding and the second secondary coil segment.

[0112] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A push-pull power amplifier circuit, characterized in that: The invention comprises a differential amplifier circuit, a first balun, a first output matching circuit and a second output matching circuit; the differential amplifier circuit comprises a first power amplifier and a second power amplifier; the first balun comprises a primary winding and a secondary winding; the secondary winding comprises a first secondary coil segment and a second secondary coil segment; The first end of the primary winding is connected to the output end of the first power amplifier, and the second end of the primary winding is connected to the output end of the second power amplifier; the first end of the first secondary coil segment is connected to the first output matching circuit, and the second end of the first secondary coil segment is grounded; the first end of the second secondary coil segment is connected to the second output matching circuit, and the second end of the second secondary coil segment is grounded; When the working mode of the push-pull power amplifier circuit is the first mode, a first radio frequency output signal is output through the first output matching circuit; when the working mode of the push-pull power amplifier circuit is the second mode, a second radio frequency output signal is output through the second output matching circuit; The first output matching circuit includes a first switching switch and a first matching network; the first end of the first matching network is connected to the first end of the first secondary coil segment, and the second end of the first matching network is grounded; the third end of the first matching network is connected to the first end of the first switching switch; when the working mode of the push-pull power amplifier circuit is the second mode, the first switching switch is disconnected, and the second output matching circuit and the first matching network jointly participate in the output impedance matching of the push-pull power amplifier circuit; And / or, the second output matching circuit includes a second switching switch and a second matching network; the first end of the second matching network is connected to the first end of the second secondary coil segment, the second end of the second matching network is grounded, and the third end of the second matching network is connected to the first end of the second switching switch; when the working mode of the push-pull power amplifier circuit is the first mode, the second switching switch is disconnected, and the first output matching circuit and the second matching network jointly participate in the output impedance matching of the push-pull power amplifier circuit.

2. The push-pull power amplifier circuit according to claim 1, characterized in that: When the working mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit and part of the second output matching circuit jointly participate in the output impedance matching of the push-pull power amplifier circuit; And / or, when the operation mode of the push-pull power amplifier circuit is the second mode, the second output matching circuit and part of the first output matching circuit jointly participate in the output impedance matching of the push-pull power amplifier circuit.

3. The push-pull power amplifier circuit according to claim 1, characterized in that: The first matching network includes a second capacitor, a first end of the second capacitor is connected to the first end of the first switch, and a second end of the second capacitor is grounded; the first output matching circuit also includes a fifth capacitor, one end of the fifth capacitor is connected to the second end of the first switch; and a second end of the fifth capacitor is grounded; The second matching network includes a fourth capacitor, a first end of the fourth capacitor is connected to the first end of the second switching switch, and a second end of the fourth capacitor is grounded; the second output matching circuit also includes a sixth capacitor, one end of the sixth capacitor is connected to the second end of the second switching switch; the second end of the sixth capacitor is grounded.

4. The push-pull power amplifier circuit according to claim 3, characterized in that: The first matching network also includes a first capacitor, a first end of which is connected to the first end of the first secondary coil segment, and a second end of which is connected to the first end of the first switching switch and the first end of the second capacitor; the second matching network also includes a third capacitor, a first end of which is connected to the first end of the second secondary coil segment, and a second end of which is connected to the first end of the second switching switch and the first end of the fourth capacitor.

5. The push-pull power amplifier circuit as claimed in claim 3, characterized in that: The push-pull power amplifier circuit also includes an adjustment matching circuit; the adjustment matching circuit is arranged between the differential amplifier circuit and the first balun; the adjustment matching circuit is configured to perform impedance matching on the push-pull power amplifier circuit based on the working mode of the push-pull power amplifier circuit.

6. The push-pull power amplifier circuit according to claim 1, characterized in that: The push-pull power amplifier circuit also includes a first switchable harmonic suppression circuit and a second switchable harmonic suppression circuit; A first terminal of the first switchable harmonic suppression circuit is connected to a first input terminal of the first balun, and a second terminal of the first switchable harmonic suppression circuit is grounded; A first terminal of the second switchable harmonic suppression circuit is connected to a second input terminal of the first balun, and a second terminal of the second switchable harmonic suppression circuit is grounded; The capacitance value presented by the first switchable harmonic suppression circuit and the capacitance value presented by the second switchable harmonic suppression circuit are negatively correlated with the operating frequency band of the push-pull power amplifier circuit.

7. The push-pull power amplifier circuit according to claim 1, characterized in that: When the push-pull power amplifier circuit operates in a first frequency band, a first RF output signal is output through the first output matching circuit; when the push-pull power amplifier circuit operates in a second frequency band, a second RF output signal is output through the second output matching circuit, and the first frequency band is greater than the second frequency band.

8. The push-pull power amplifier circuit according to claim 7, characterized in that: The coupling degree between the primary winding and the first secondary coil segment is smaller than the coupling degree between the primary winding and the second secondary coil segment.

9. The push-pull power amplifier circuit according to claim 8, characterized in that: The first balun is applied on a substrate, and the substrate includes a first metal layer and a second metal layer arranged adjacent to each other; the first secondary coil segment is arranged on the first metal layer, and the second secondary coil segment is arranged on the second metal layer; the primary winding of the first balun is coupled with the first secondary coil segment in the same layer, and the primary winding of the first balun is coupled with the second secondary coil segment in upper and lower layers.

10. A push-pull power amplifier circuit, characterized in that: The invention comprises a differential amplifier circuit, a first balun, a first output matching circuit and a second output matching circuit; the differential amplifier circuit comprises a first power amplifier and a second power amplifier; the first balun comprises a primary winding and a secondary winding; the secondary winding comprises a first secondary coil segment and a second secondary coil segment; The first end of the primary winding is connected to the output end of the first power amplifier, and the second end of the primary winding is connected to the output end of the second power amplifier; the first end of the first secondary coil segment is connected to the first output matching circuit, and the second end of the first secondary coil segment is grounded; the first end of the second secondary coil segment is connected to the second output matching circuit, and the second end of the second secondary coil segment is grounded; When the working mode of the push-pull power amplifier circuit is the first mode, a first radio frequency output signal is output through the first output matching circuit; when the working mode of the push-pull power amplifier circuit is the second mode, a second radio frequency output signal is output through the second output matching circuit; The first output matching circuit includes a first switching switch and a first matching network; a first end of the first switching switch is connected to a first end of the first secondary coil segment, and a second end of the first switching switch is connected to the first matching network; The second output matching circuit includes a second switching switch and a second matching network; a first end of the second switching switch is connected to a first end of the second secondary coil segment, and a second end of the second switching switch is connected to the second matching network; When the working mode of the push-pull power amplifier circuit is the first mode, the first switch is turned on and the second switch is turned off; When the working mode of the push-pull power amplifier circuit is the second mode, the first switch is disconnected and the second switch is turned on; The first matching network includes a first capacitor, a second capacitor and a first inductor; the first end of the first capacitor is connected to the second end of the first switch, the second end of the first capacitor is connected to the first end of the second capacitor and the first end of the first inductor, the second end of the second capacitor is grounded, and the second end of the first inductor is an output node of the first matching network; the first capacitor, the second capacitor and the first inductor are used to participate in the output impedance matching of the push-pull power amplifier circuit to flexibly adjust the output impedance of the push-pull power amplifier circuit; The second matching network includes a third capacitor, a fourth capacitor and a second inductor; the first end of the third capacitor is connected to the second end of the second switch, the second end of the third capacitor is connected to the first end of the fourth capacitor and the first end of the second inductor, the second end of the fourth capacitor is grounded, and the second end of the second inductor is an output node of the second matching network; the third capacitor, the fourth capacitor and the second inductor are used to participate in the output impedance matching of the push-pull power amplifier circuit to flexibly adjust the output impedance of the push-pull power amplifier circuit; The push-pull power amplifier circuit further includes an adjustable capacitor; the primary winding includes a first primary coil segment and a second primary coil segment; The first end of the first primary coil segment is coupled to the output end of the first power amplifier, and the second end of the first primary coil segment is connected to the first end of the adjustable capacitor; A first end of the second primary coil segment is coupled to an output end of the second power amplifier, and a second end of the second primary coil segment is connected to a second end of the adjustable capacitor.

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