CN116846351A

CN116846351A - Push-pull power amplifying circuit

Info

Publication number: CN116846351A
Application number: CN202210289653.0A
Authority: CN
Inventors: 林少鑫; 曹原; 雷传球; 倪建兴
Original assignee: Radrock Shenzhen Technology Co Ltd
Current assignee: Radrock Shenzhen Technology Co Ltd
Priority date: 2022-03-23
Filing date: 2022-03-23
Publication date: 2023-10-03
Also published as: WO2023179244A1

Abstract

The invention discloses a push-pull power amplifying circuit which comprises a differential amplifying circuit, a first balun, a first output matching circuit and a second output matching circuit. The secondary winding of the first balun comprises a first secondary coil section and a second secondary coil section; the first end of the primary winding is connected with the output end of the first power amplifier, and the second end of the primary winding is connected with the output end of the second power amplifier; the first end of the first secondary coil section is connected with the first output matching circuit, and the second end of the first secondary coil section is grounded; the first end of the second secondary coil section is connected with the second output matching circuit, and the second end of the second secondary coil section is grounded; when the working mode of the push-pull power amplifying circuit is a first mode, the first output matching circuit outputs a first radio frequency output signal; when the working mode of the push-pull power amplifying circuit is a second mode, the second output matching circuit outputs a second radio frequency output signal. The technical scheme can optimize the bandwidth performance of the push-pull power amplifying circuit.

Description

Push-pull power amplifying circuit

Technical Field

The invention relates to the technical field of radio frequency, in particular to a push-pull power amplifying circuit.

Background

The key performance goal of the fifth generation mobile communication technology (5G) is that the transmission rate is greatly improved compared with that of 4G, and the new technology of 5G needs to adopt a radio frequency front end with higher frequency, larger working bandwidth and higher order of QAM modulation, so that the design of a power amplifier of the radio frequency front end is more severely required.

However, in designing a push-pull power amplifying circuit, the performance of the operating bandwidth of the push-pull power amplifying circuit is ignored for other performances of the push-pull power amplifying circuit (e.g., design requirements or performance indicators such as high frequency or high power). Therefore, how to increase the operating bandwidth of the push-pull power amplifying circuit while ensuring the overall performance of the push-pull power amplifying circuit is a problem to be solved at present.

Disclosure of Invention

The embodiment of the invention provides a push-pull power amplifying circuit, which aims to solve the problem of poor bandwidth performance of the push-pull power amplifying circuit.

A push-pull power amplifying circuit comprises a differential amplifying circuit, a first balun, a first output matching circuit and a second output matching circuit; the differential amplifying circuit comprises a first power amplifier and a second power amplifier; the first balun includes a primary winding and a secondary winding; the secondary winding comprises a first secondary coil section and a second secondary coil section;

The first end of the primary winding is connected with the output end of the first power amplifier, and the second end of the primary winding is connected with the output end of the second power amplifier; a first end of the first secondary coil section is connected with the first output matching circuit, and a second end of the first secondary coil section is grounded; the first end of the second secondary coil section is connected with the second output matching circuit, and the second end of the second secondary coil section is grounded;

when the working mode of the push-pull power amplifying circuit is a first mode, outputting a first radio frequency output signal through the first output matching circuit; and when the working mode of the push-pull power amplifying circuit is a second mode, outputting a second radio frequency output signal through the second output matching circuit.

Further, when the working mode of the push-pull power amplifying circuit is a first mode, the first output matching circuit and part of the second output matching circuit participate in the output impedance matching of the push-pull power amplifying circuit together;

and/or when the working mode of the push-pull power amplifying circuit is a second mode, the second output matching circuit and part of the first output matching circuit participate in the output impedance matching of the push-pull power amplifying circuit together.

Further, the first output matching circuit comprises a first change-over switch and a first matching network; a first end of the first matching network is connected with a first end of the first secondary coil section, and a second end of the first matching network is grounded; the third end of the first matching network is connected with the first end of the first change-over switch; when the working mode of the push-pull power amplifying circuit is a second mode, the first switch is turned off, and the second output matching circuit and the first matching network participate in output impedance matching of the push-pull power amplifying circuit together;

and/or the second output matching circuit comprises a second change-over switch and a second matching network; the first end of the second matching network is connected with the first end of the second secondary coil section, the second end of the second matching network is grounded, and the third end of the second matching network is connected with the first end of the second change-over switch; when the working mode of the push-pull power amplifying circuit is a first mode, the second change-over switch is disconnected, and the first output matching circuit and the second matching network participate in output impedance matching of the push-pull power amplifying circuit together.

Further, the first matching network comprises a second capacitor, a first end of the second capacitor is connected with a first end of the first change-over switch, and a second end of the second capacitor is grounded; the first output matching circuit further comprises a fifth capacitor, and one end of the fifth capacitor is connected with the second end of the first change-over switch; the second end of the fifth capacitor is grounded;

the second matching network comprises a fourth capacitor, a first end of the fourth capacitor is connected with a first end of the second change-over switch, and a second end of the fourth capacitor is grounded; the second output matching circuit further comprises a sixth capacitor, and one end of the sixth capacitor is connected with the second end of the second change-over switch; the second end of the sixth capacitor is grounded.

Further, the first matching network further comprises a first capacitor, a first end of the first capacitor is connected with a first end of the first secondary coil section, and a second end of the first capacitor is connected with a first end of the first change-over switch and a first end of the first two-capacitor; the second matching network further comprises a third capacitor, a first end of the third capacitor is connected with the first end of the second secondary coil section, and a second end of the third capacitor is connected with the first end of the second change-over switch and the first end of the fourth capacitor.

Further, the push-pull power amplifying circuit further comprises an adjusting and matching circuit; the adjusting and matching circuit is arranged between the differential amplifying circuit and the first balun; the adjustment matching circuit is configured to impedance match the push-pull power amplification circuit based on an operating mode of the push-pull power amplification circuit.

Further, the first output matching circuit comprises a first change-over switch and a first matching network; the first end of the first change-over switch is connected with the first end of the first secondary coil section, and the second end of the first change-over switch is connected with the first matching network;

the second output matching circuit comprises a second change-over switch and a second matching network; the first end of the second change-over switch is connected with the first end of the second secondary coil section, and the second end of the second change-over switch is connected with the second matching network;

when the working mode of the push-pull power amplifying circuit is a 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 amplification circuit is a second mode, the first switching switch is turned off, and the second switching switch is turned on.

Further, the first matching network comprises a first capacitor, a second capacitor and a first inductor; the first end of the first capacitor is connected with the second end of the first change-over switch, the second end of the first capacitor is connected with 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 second matching network comprises a third capacitor, a fourth capacitor and a second inductor; the first end of the third capacitor is connected with the second end of the second change-over switch, the second end of the third capacitor is connected with 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.

Further, the push-pull power amplifying circuit further comprises an adjustable capacitor; the primary winding includes a first primary coil section and a second primary coil section;

a first end of the first primary coil section is coupled to the output end of the first power amplifier, and a second end of the first primary coil section is connected with a first end of the adjustable capacitor;

A first end of the second primary coil section is coupled to the output of the second power amplifier, and a second end of the second primary coil section is connected to a second end of the adjustable capacitance.

Further, the push-pull power amplifying circuit further comprises a first switchable harmonic suppression circuit and a second switchable harmonic suppression circuit;

a first end of the first switchable harmonic suppression circuit is connected with a first input end of the first balun, and a second end of the first switchable harmonic suppression circuit is grounded;

a first end of the second switchable harmonic suppression circuit is connected with a second input end of the first balun, and a second end 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 inversely related to the working frequency band of the push-pull power amplification circuit.

Further, when the push-pull power amplifying circuit works in a first frequency band, a first radio frequency output signal is output through the first output matching circuit; when the push-pull power amplifying circuit works in a second frequency band, a second radio frequency output signal is output through the second output matching circuit, and the first frequency band is larger than the second frequency band.

Further, the primary winding is coupled to the first secondary coil section less than the primary winding is coupled to the second secondary coil section.

Further, the first balun is applied to a substrate, and the substrate comprises a first metal layer and a second metal layer which are adjacently arranged; the first secondary coil section is arranged on the first metal layer, and the second secondary coil section is arranged on the second metal layer; the primary winding of the first balun is coupled to the first secondary coil section in a same layer, and the primary winding of the first balun is coupled to the second secondary coil section in upper and lower layers.

The push-pull power amplifying circuit comprises a differential amplifying circuit, a first balun, a first output matching circuit and a second output matching circuit. The differential amplifying circuit comprises 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 section and a second secondary coil section. The first end of the primary winding is connected with the output end of the first power amplifier, and the second end of the primary winding is connected with the output end of the second power amplifier; the first end of the first secondary coil section is connected with the first output matching circuit, and the second end of the first secondary coil section is grounded; the first end of the second secondary coil section is connected with the second output matching circuit, and the second end of the second secondary coil section is grounded. In this embodiment, the first end of the first secondary coil section is connected to the first output matching circuit, the second end of the first secondary coil section is grounded, and the first end of the second secondary coil section is connected to the second output matching circuit, so that when the push-pull power amplifying circuit is in the first mode, the first radio frequency output signal is output through the first output matching circuit, and when the push-pull power amplifying circuit is in the second mode, the second radio frequency output signal is output through the second output matching circuit, thereby achieving the purpose of switching different working modes in one push-pull power amplifying circuit, ensuring the output impedance matching of the push-pull power amplifying circuit in different working modes, and further optimizing the bandwidth performance of the push-pull power amplifying circuit.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the description of the embodiments of the present invention will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a push-pull power amplifier circuit according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a push-pull power amplifier according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a push-pull power amplifier according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a push-pull power amplifier according to an embodiment of the present invention;

fig. 5 is another schematic circuit diagram of a push-pull power amplifying circuit according to an embodiment of the present invention.

In the figure:

10. a differential amplifying circuit; 20. a first balun; 30. a first output matching circuit; 31. a first matching network; 40. a second output matching circuit; 41. a second matching network; 50. adjusting a matching circuit; 60. A first switchable harmonic rejection circuit; 70. a second switchable harmonic rejection circuit.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be understood that the present invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the dimensions and relative dimensions of layers and regions may be exaggerated for the same elements throughout for clarity.

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

Spatially relative terms, such as "under …," "under …," "below," "under …," "above …," "above," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements or features described as "under" or "beneath" other elements would then be oriented "on" the other elements or features. Thus, the exemplary terms "under …" and "under …" may include both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

In the following description, for the purpose of providing a thorough understanding of the present invention, detailed structures and steps are presented in order to illustrate the technical solution presented by the present invention. Preferred embodiments of the present invention are described in detail below, however, the present invention may have other embodiments in addition to these detailed descriptions.

The present embodiment provides a push-pull power amplifying circuit, as shown in fig. 1, including a differential amplifying circuit 10, a first balun 20, a first output matching circuit 30, and a second output matching circuit 40; the differential amplification circuit 10 includes a first power amplifier M1, a second power amplifier M2; the first balun 20 includes a primary winding and a secondary winding; the secondary winding comprises a first secondary coil section and a second secondary coil section; the first end of the primary winding is connected with the output end of the first power amplifier M1, and the second end of the primary winding is connected with the output end of the second power amplifier M2; a first end of the first secondary coil section is connected with the first output matching circuit 30, and a second end of the first secondary coil section is grounded; the first end of the second secondary coil section is connected to the second output matching circuit 40, and the second end of the second secondary coil section is grounded; when the operation mode of the push-pull power amplifying circuit is the first mode, outputting a first radio frequency output signal through the first output matching circuit 30; when the operation mode of the push-pull power amplifying circuit is the second mode, the second radio frequency output signal is output through the second output matching circuit 40.

Wherein the push-pull power amplifying circuit can work in different working modes. For example, the operation mode may be an operation frequency band of the push-pull power amplifying circuit, or a power mode of the push-pull power amplifying circuit, or the like. For example: when the push-pull power amplifying circuit operates in different operating frequency bands, the operating frequency band may be a high frequency band, a medium frequency band or a low frequency band. When the push-pull power amplifying circuit operates in different power modes, the power modes may be a High Power Mode (HPM) or a Low Power Mode (LPM).

Preferably, the operation mode in this embodiment is an operation frequency band of the push-pull power amplifying circuit. The first mode refers to a first frequency band of the push-pull power amplifying circuit, and the second mode refers to a second frequency band of the push-pull power amplifying circuit. The first frequency band and the second frequency band are different frequency bands, namely any two frequency bands of a high frequency band, a medium frequency band or a low frequency band.

In one embodiment, the push-pull power amplifying circuit includes a differential amplifying circuit 10, and the differential amplifying circuit 10 is configured to amplify two radio frequency signals with equal magnitude and opposite phases.

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 amplification circuit 10 includes a first power amplifier M1 and a second power amplifier M2. The first power amplifier M1 is configured to amplify a first radio frequency input signal to output a first radio frequency amplified signal, and the second power amplifier M2 is configured to amplify a second radio frequency input signal to output a second radio frequency amplified signal. Alternatively, the first and second power amplifiers M1 and M2 may be BJT transistors (e.g., HBT transistors) or field effect transistors.

As an example, the first radio frequency input signal and the second radio frequency input signal may be signals output by a preceding stage circuit of the differential amplifying circuit 10. Optionally, the pre-stage circuit comprises a second balun. Illustratively, the first input terminal of the second balun is configured to receive a first radio frequency signal, the second input terminal of the second balun is grounded, the first output terminal of the second balun is connected to the input terminal of the first power amplifier M1, the second output terminal of the second balun is connected to the input terminal of the second power amplifier M2, and the second balun is configured to convert the first radio frequency signal into a first radio frequency input signal and a second radio frequency input signal and output the first radio frequency input signal to the first power amplifier M1, so that the first radio frequency input signal is amplified by the first power amplifier M1, and output the second radio frequency input signal to the second power amplifier M2, so that the second radio frequency input signal is amplified by the second power amplifier M2.

In a specific embodiment, the push-pull power amplifying 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 section and a second secondary coil section. The first end of the primary winding is connected with the output end of the first power amplifier M1 and is configured to receive a first radio frequency amplified signal output by the first power amplifier M1, the second end of the primary winding is connected with the output end of the second power amplifier M2 and is configured to receive a second radio frequency amplified signal output by the second power amplifier M2, the first end of the first secondary coil section is connected with the first output matching circuit 30, and the second end of the first secondary coil section is grounded. When the operation mode of the push-pull power amplifying circuit is the first mode, the primary winding and the first secondary coil section are coupled to each other, the first radio frequency amplifying signal and the second radio frequency amplifying signal are subjected to synthesis conversion, and the first radio frequency output signal is output through the first output matching circuit 30. When the operation mode of the push-pull power amplifying circuit is the second mode, the primary winding and the second secondary winding section are coupled to each other, the first radio frequency amplifying signal and the second radio frequency amplifying signal are subjected to synthesis conversion, and the second radio frequency output signal is output through the second output matching circuit 40. In this embodiment, when the operation mode of the push-pull power amplifying circuit is the first mode, the first output matching circuit 30 outputs the first radio frequency output signal, and when the operation mode of the push-pull power amplifying circuit is the second mode, the second output matching circuit 40 outputs the second radio frequency output signal, so as to achieve the purpose of switching different operation modes in one push-pull power amplifying circuit, and ensure the output impedance matching of the push-pull power amplifying circuit in different operation modes, thereby optimizing the bandwidth performance of the push-pull power amplifying circuit.

In a specific embodiment, the first power amplifier M1 is a BJT tube, including a base, a collector and an emitter, where the base of the first power amplifier M1 receives an input first radio frequency 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 and comprises a base electrode, a collector electrode and an emitter electrode, the base electrode of the second power amplifier M2 receives an input second radio frequency input signal, the collector electrode of the second power amplifier M2 is connected with the second end of the primary winding, and the emitter electrode of the second power amplifier M2 is grounded.

In the present embodiment, the push-pull power amplifying circuit includes a differential amplifying circuit 10, a first balun 20, a first output matching circuit 30, and a second output matching circuit 40. The differential amplification 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 section and a second secondary coil section. The first end of the primary winding is connected with the output end of the first power amplifier M1, and the second end of the primary winding is connected with the output end of the second power amplifier M2; a first end of the first secondary coil section is connected with the first output matching circuit 30, and a second end of the first secondary coil section is grounded; the first end of the second secondary coil section is connected to a second output matching circuit 40 and the second end of the second secondary coil section is grounded. In this embodiment, by connecting the first end of the first secondary coil segment with the first output matching circuit 30, connecting the second end of the first secondary coil segment with the second output matching circuit 40, and connecting the first end of the second secondary coil segment with the second end of the second secondary coil segment, when the operation mode of the push-pull power amplifying circuit is the first mode, the first radio frequency output signal is output through the first output matching circuit 30, and when the operation mode of the push-pull power amplifying circuit is the second mode, the second radio frequency output signal is output through the second output matching circuit 40, thereby achieving the purpose of switching different operation modes in one push-pull power amplifying circuit, and ensuring the output impedance matching of the push-pull power amplifying circuit in different operation modes, thereby optimizing the bandwidth performance of the push-pull power amplifying circuit.

In one embodiment, when the operation mode of the push-pull power amplifying circuit is the first mode, the first output matching circuit 30 and a part of the second output matching circuit 40 participate in the output impedance matching of the push-pull power amplifying circuit together. And/or, when the operation mode of the push-pull power amplifying circuit is the second mode, the second output matching circuit 40 and part of the first output matching circuit 30 participate in the output impedance matching of the push-pull power amplifying circuit together.

In a specific embodiment, by connecting the first end of the first secondary coil section with the first output matching circuit 30, connecting the second end of the first secondary coil section with the second output matching circuit 40, connecting the second end of the second secondary coil section with the second end of the second secondary coil section, connecting some components (e.g., capacitors) in the first output matching circuit 30 with the ground, and connecting some components (e.g., capacitors) in the second output matching circuit 40 with the ground, when the operation mode of the push-pull power amplifying circuit is the first mode, the second secondary coil section 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 participate in the output impedance matching of the push-pull power amplifying circuit together, so as to perform impedance matching on the push-pull power amplifying circuit whose operation mode is the first mode. When the working mode of the push-pull power amplifying circuit is the second mode, the first secondary coil section and part of the first output matching circuit 30 are ensured to form a grounding loop, so that the second output matching circuit 40 and part of the first output matching circuit 30 participate in the output impedance matching of the push-pull power amplifying circuit together, and the push-pull power amplifying circuit with the working mode of the first mode is impedance matched.

In the present embodiment, when the operation mode of the push-pull power amplifying circuit is the first mode, the first output matching circuit 30 and part of the second output matching circuit 40 participate in the output impedance matching of the push-pull power amplifying circuit together. And/or, when the working mode of the push-pull power amplifying circuit is the second mode, the second output matching circuit 40 and part of the first output matching circuit 30 participate in the output impedance matching of the push-pull power amplifying circuit together, so that when the push-pull power amplifying circuit works in different working modes, the first output matching circuit 30 and the second output matching circuit 40 can participate in the impedance matching together, the flexibility of realizing the output impedance matching in different working modes is improved, the output impedance matching of the push-pull power amplifying circuit in different working modes can be ensured, and the bandwidth performance of the push-pull power amplifying circuit is optimized.

In one embodiment, as shown in fig. 1, the first output matching circuit 30 includes a first switch S311 and a first matching network 31; a first end of the first matching network 31 is connected with a first end of the first secondary coil section, and a second end of the first matching network 31 is grounded; the third terminal of the first matching network 31 is connected to a first terminal of a first switching switch S311. The second output matching circuit 40 includes a second changeover 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 winding section, 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 switch S411.

When the operation mode of the push-pull power amplifying circuit is the first mode, the first switch S311 is turned on, and the second switch S411 is turned off, and since the second matching network 41 is disposed between the second switch S411 and the first end of the second secondary coil section and is connected to the ground terminal, when the operation mode of the push-pull power amplifying circuit is the first mode, the first output matching circuit 30 and the second matching network 41 participate in the output impedance matching of the push-pull power amplifying circuit together, so as to improve the flexibility of realizing the output impedance matching in the first operation mode. When the operation mode of the push-pull power amplifying circuit is the second mode, the first switch S311 is turned off, and the second switch S411 is turned on, and since the first matching network 31 is disposed between the first switch S311 and the first end of the first secondary coil section and is connected to the ground, when the operation mode of the push-pull power amplifying circuit is the second mode, the second output matching circuit 40 and the first matching network 31 participate in the output impedance matching of the push-pull power amplifying circuit together.

In a specific embodiment, the first output matching circuit 30 includes a first switch S311 and a first matching network 31, a first end of the first matching network 31 is connected to a first end of the first secondary coil section, and a second end of the first matching network 31 is grounded; the first end of the first switch S311 is coupled to the first matching network 31, and the second end of the first switch S311 is an output node of the first output matching circuit 30, and is configured to output a first radio frequency output signal when the operation mode of the push-pull power amplifying circuit is the first mode. The second output matching circuit 40 includes a second changeover 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 winding segment, the second end of the second matching network 41 is grounded, the first end of the second switch S411 is coupled to the second matching network 41, the second end of the second switch S411 is an output node of the second output matching circuit 40, and the second output node is configured to output a second radio frequency output signal when the operation mode of the push-pull power amplifying circuit is the second mode.

In this embodiment, when the operation mode of the push-pull power amplifying circuit is the first mode, for example, when the operation frequency band of the push-pull power amplifying circuit is the mid-frequency band, the first switch S311 is turned on, and the second switch S411 is turned off, so that the second secondary coil section and the second matching network 41 form a grounding loop, and the first output matching circuit 30 and the second matching network 41 participate in the output impedance matching of the push-pull power amplifying circuit together, thereby improving the flexibility of impedance adjustment when the push-pull power amplifying circuit operates in the mid-frequency band mode. When the working mode of the push-pull power amplifying circuit is the second mode, for example, when the working frequency range of the push-pull power amplifying circuit is the high frequency range, the first switch S311 is disconnected, the second switch S411 is conducted, so that the first secondary coil section and the first matching network 31 form a grounding loop, and the second output matching circuit 40 and the first matching network 31 participate in the output impedance matching of the push-pull power amplifying circuit together, so that the flexibility of impedance adjustment when the push-pull power amplifying circuit works in the high frequency range mode is improved, the aim of switching different working modes in one push-pull power amplifying circuit is fulfilled, the output impedance matching of the push-pull power amplifying circuit in different working modes can be guaranteed, and the bandwidth performance of the push-pull power amplifying circuit is optimized.

Optionally, the first matching network 31 and the second matching network 41 are networks formed by capacitive and/or inductive series and/or parallel combinations.

Preferably, since the impedance of the first secondary coil section and the second secondary coil section in the first balun 20 is inductive, the first matching network 31 and the second matching network 41 formed by parallel connection and/or series connection of capacitors are selected, so that the output impedance of the push-pull power amplifying circuit is conveniently adjusted to realize the output impedance matching of the push-pull power amplifying circuit even though the first matching network 31 and the second matching network 41 are capacitive.

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 switch, and a second end of the second capacitor is grounded; the second end of the first switch is an output node of the first matching network 31; the first output matching circuit 30 further includes a fifth capacitor, and one end of the fifth capacitor is connected to the second end of the first switch; the fifth capacitor is grounded, and the second capacitor and the fifth capacitor may be connected to different grounds respectively or may be connected to the same ground.

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 switch, and a second end of the fourth capacitor is grounded; the second end of the second switch is an output node of the second matching network 41; the second output matching circuit 40 further includes a sixth capacitor, where one end of the sixth capacitor is connected to the second end of the second switch; the sixth capacitor is grounded, and the second capacitor and the fifth capacitor may be connected to different grounds respectively or may be connected to the same ground.

When the operation mode of the push-pull power amplifier circuit is the first mode, the first output matching circuit 30 mainly performs an impedance matching function, and the capacitance to ground in the second output matching circuit 40 is not easily excessively large. When the working mode of the push-pull power amplifying circuit is the second mode, the second output matching circuit 40 mainly has an impedance matching function, and the capacitance value of the capacitance to ground in the second output matching circuit 40 needs to be excessively large. Similarly, when the operation mode of the push-pull power amplifying circuit is the second mode, the second output matching circuit 40 mainly plays a role of impedance matching, and at this time, the capacitance value of the capacitance to ground in the first output matching circuit 30 is not easy to be excessively large, and when the operation mode of the push-pull power amplifying circuit is the first mode, the first output matching circuit 30 mainly plays a role of impedance matching, and at this time, the capacitance value of the capacitance to ground in the first output matching circuit 30 needs to be relatively large.

In view of this, the present application connects the first end of the second capacitor with the first end of the first switch, and the second end of the second capacitor is grounded; the second end of the first switch is an output node of the first matching network 31, and one end of the fifth capacitor is connected with the second end of the first 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 switch, the second end of the second switch is an output node of the second matching network 41, and one end of the sixth capacitor is connected to the second end of the second switch; the second end of the sixth capacitor is connected to the second end of the fourth capacitor, so that it is known that when the operation mode of the push-pull power amplifying circuit is the first mode, the first switch is turned off, and 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 ground capacitor to participate in impedance matching, and because the second switch is turned off, only the fourth capacitor in the second output matching circuit 40 forms a smaller ground capacitor to participate in impedance matching. When the working mode of the push-pull power amplifying circuit is the second mode, the second 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 ground capacitor to participate in impedance matching, and because the first switch is turned off, only the fourth capacitor in the first output matching circuit 30 forms a smaller ground capacitor to participate in impedance matching, so that the output impedance of the push-pull power amplifying circuit can be flexibly adjusted, and impedance matching is realized.

In an embodiment, as shown in fig. 1, the first matching network 31 includes a first capacitor C311 and a second capacitor C312, a first end of the first capacitor C311 is connected to a first end of the first secondary coil section, a second end of the first capacitor C311 is connected to a first end of the first switch S311 and a first end of the second capacitor C312, a second end of the second capacitor C312 is grounded, and a second end of the first switch S311 is an output node of the first matching network 31.

The second matching network 41 comprises a third capacitor C411 and a fourth capacitor C412, wherein a first end of the third capacitor C411 is connected with a first end of the second secondary coil section, a second end of the third capacitor C411 is connected with a first end of the second switch S411 and a first end of the fourth capacitor C412, and a second end of the fourth capacitor C412 is grounded; the second terminal of the second switch S411 is an output node of the second matching network 41.

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

The second output matching circuit 40 further includes a sixth capacitor C413, where one end of the sixth capacitor C413 is connected to the second end of the second switch S411; a second terminal of the sixth capacitor C413 is connected to a second terminal of the fourth capacitor C412.

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 an output node of the first matching network 31.

In a specific embodiment, the second matching network 41 includes a third capacitor C411 and a fourth capacitor C412, a first end of the third capacitor C411 is connected to a first end of the second secondary winding section, a second end of the third capacitor C411 is connected to a first end of the second switch S411 and a first end of the fourth capacitor C412, and a second end of the fourth capacitor C412 is grounded; the second terminal of the second switch S411 is an output node of the second matching network 41.

In the above circuit configuration, when the operating frequency band of the push-pull power amplifying circuit is the first frequency band (for example, the high frequency band), the first switch S311 is turned on, and the second switch S411 is turned off, so that the second secondary winding section, the third capacitor C411 and the fourth capacitor C412 form a ground loop, and the first output matching circuit 30 and the second secondary winding section, the third capacitor C411 and the fourth capacitor C412 participate in the output impedance matching of the push-pull power amplifying circuit together. When the working frequency band of the push-pull power amplification circuit is a second frequency band (for example, a medium frequency band), the first switch S311 is disconnected, the second switch S411 is conducted, so that the first secondary coil section, the first capacitor C311 and the second capacitor C312 form a grounding loop, the second output matching circuit 40 and the second secondary coil section, the first capacitor C311 and the second capacitor C312 participate in the output impedance matching of the push-pull power amplification circuit together, the purpose of realizing switching of different working modes in one push-pull power amplification circuit is achieved, the output impedance matching of the push-pull power amplification circuit in different working modes can be guaranteed, and further the bandwidth performance of the push-pull power amplification circuit is optimized.

In a specific embodiment, as shown in fig. 2, the first output matching circuit 30 further 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 further includes a sixth capacitor C413, where 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 operating frequency band of the push-pull power amplifying circuit is the first frequency band, the first switch S311 is turned off, the second switch S411 is turned on, the third capacitor C411, the fourth capacitor C412 and the sixth capacitor C413 in the second output matching circuit 40, and the second secondary winding section, the first capacitor C311 and the second capacitor C312 participate in the output impedance matching of the push-pull power amplifying circuit. When the working frequency band of the push-pull power amplifying circuit is the second frequency band, the first switch S311 is turned on, the second 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, and the second secondary coil section, the third capacitor C411 and the fourth capacitor C412 participate in the output impedance matching of the push-pull power amplifying circuit.

In this embodiment, when the operating frequency band of the push-pull power amplifying circuit is the first frequency band, the third capacitor C411, the fourth capacitor C412 and the sixth capacitor C413 mainly play a role in 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 amplifying circuit is the second frequency band, the first capacitor C311, the second capacitor C312 and the fifth capacitor C313 mainly play a role in impedance matching, and the third capacitor C411 and the fourth capacitor C412 play a role in auxiliary adjustment. Therefore, when the operating frequency band of the push-pull power amplifying circuit is the first frequency band, the first switch S311 is turned off, the second 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 performing impedance matching, and when the operating frequency band of the push-pull power amplifying circuit is the second frequency band, the first switch S311 is turned on, the second switch S411 is turned off, 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 performing impedance matching, so as to more flexibly adjust the output impedance of the push-pull power amplifying circuit.

In one embodiment, as shown in fig. 3, the push-pull power amplification circuit further includes an adjustment matching circuit 50; the adjustment matching circuit 50 is provided between the differential amplification circuit 10 and the first balun 20; the adjustment matching circuit 50 is configured to impedance match the push-pull power amplifying circuit based on an operation mode of the push-pull power amplifying circuit.

In one embodiment, the tuning matching circuit 50 is configured to impedance match the fundamental signal of the push-pull power amplifying circuit based on the operating frequency band of the push-pull power amplifying circuit.

In a specific embodiment, the adjustment matching circuit 50 includes a first capacitance adjustment circuit, a first inductance L51 adjustment circuit, and a second inductance L52 adjustment circuit.

As an example, a first end of the first inductance L51 adjusting circuit is connected to the output end of the first power amplifier M1, a second end of the first inductance L51 adjusting circuit is connected to the first end of the primary winding and the first end of the first capacitance adjusting circuit, and the first inductance L51 adjusting circuit is configured to perform inductance value switching based on an operation mode of the push-pull power amplifying circuit.

As an example, a first end of the second inductance L52 adjusting circuit is connected to the output end of the second power amplifier M2, a second end of the second inductance L52 adjusting circuit is connected to the second end of the primary winding and the second end of the second capacitance C312 adjusting circuit, and the second inductance L52 adjusting circuit is configured to perform inductance value switching based on the operation mode of the push-pull power amplifying circuit.

As an example. The first capacitance adjustment circuit is configured to switch capacitance values based on an operation mode of the push-pull power amplification circuit.

Alternatively, as shown in fig. 4, the first inductance L51 adjusting circuit includes a first inductance L51 and a third switch S51 connected in parallel. The second inductance L52 adjusting circuit comprises a second inductance L52 and a fourth switch S52 which are connected in parallel; the first capacitance adjusting circuit includes a seventh capacitance C51 and a fifth switch S53 connected in series.

In this embodiment, when the working frequency band of the push-pull power amplifying circuit is the first frequency band, the third switch S51 and the fourth switch S52 are turned off, the fifth switch S53 is turned on, the first inductor L51 and the second inductor L52 are connected to the circuit to participate in matching, and the seventh capacitor C51 is connected to the circuit to participate in matching, so as to perform impedance matching on the fundamental wave signal corresponding to the second frequency band. When the operating frequency band of the push-pull power amplifying circuit is the second frequency band, the third switch S51 and the fourth switch S52 are turned on, the fifth switch S53 is turned off, the first inductor L51 and the second inductor L52 are short-circuited, and the seventh capacitor C51 is turned off, so as to perform impedance matching on the fundamental wave signal corresponding to the first frequency band. Wherein the first frequency band is greater than the second frequency band.

In a specific embodiment, the tuning matching circuit 50 further includes a third switchable harmonic rejection circuit. The third switchable harmonic rejection circuit is configured to reject odd harmonic signals of the push-pull power amplifying circuit.

Alternatively, the odd harmonic signal may 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 amplifying circuit, the harmonic component of the third harmonic signal is largest, and therefore, the odd harmonic signal is preferably the third harmonic signal.

Optionally, as shown in fig. 4, the third switchable harmonic rejection circuit includes a third inductance L53, an eighth capacitance C52, a ninth capacitance C53, and a sixth switch S54; a first end of the third inductor L53 is connected to the output end of the first power amplifier M1 and the first end of the first inductor L51 adjusting circuit, and a second end of the third inductor L53 is connected to the first end of the eighth capacitor C52 and the first end of the sixth switch S54; the second end of the eighth capacitor C52 is connected with the output end of the second power amplifier M2 and the first end of the second inductance L52 regulating circuit; a second terminal of the sixth switch S54 is connected to a first terminal of the ninth capacitor C53, and a second terminal of the ninth capacitor C53 is connected to a second terminal of the eighth capacitor C52.

When the operation mode of the push-pull power amplifying circuit is the first mode, the sixth switch S54 is turned off, and a resonant circuit is formed by the third inductor L53 and the eighth capacitor C52. When the operation mode of the push-pull power amplifying circuit is the second mode, the sixth switch S54 is turned on, the eighth capacitor C52 and the ninth capacitor C53 are connected in parallel, the capacitance value presented by the third switchable harmonic suppression circuit is increased, and the third inductor L53 and the eighth capacitor C52 and the ninth capacitor C53 connected in parallel form a resonant circuit to suppress the odd harmonic signal of the push-pull power amplifying circuit. Wherein the first frequency band is greater than the second frequency band.

According to the resonant frequency formula:wherein f is the resonance frequency point of the third switchable harmonic suppression circuit, L is an inductance value, C is a capacitance value, and the larger the working frequency band of the push-pull power amplification circuit is, the larger the odd harmonic signal component of the push-pull power amplification circuit is, the larger the resonance 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 L53 is unchanged, the larger the resonance 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 is, the larger the capacitance value C presented by the third switchable harmonic suppression circuit is, therefore, in the embodiment, when the operation mode of the push-pull power amplification circuit is the first mode, the sixth switch S54 is turned off, only the eighth capacitor C52 is connected into the circuit, the capacitance value presented by the third switchable harmonic suppression circuit is reduced, and when the operation mode of the push-pull power amplification circuit is the second mode, the sixth switch S54 is turned on, The eighth capacitor C52 and the ninth capacitor C53 are connected in parallel, and the capacitance value presented by the third switchable harmonic suppression circuit is increased, so that the resonance frequency point of the third switchable harmonic suppression circuit is flexibly adjusted, odd harmonic signals in different working frequency bands are suppressed, and the bandwidth performance of the push-pull power amplification circuit is optimized.

In one embodiment, the first output matching circuit 30 includes a switch and a switchable network (not shown in the figure) that is a switchable network composed of at least one component of capacitance, inductance, and resistance. The first output matching circuit 30 switches according to the working modes of the push-pull power amplifying circuit to meet the output impedance matching under different working modes, so that the purpose of switching different working modes can be achieved in one push-pull power amplifying circuit, the output impedance matching of the push-pull power amplifying circuit under different working modes can be ensured, and the bandwidth performance of the push-pull power amplifying circuit is optimized.

In one embodiment, as shown in fig. 4, 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 an output node of the first matching network 31; the second matching network 41 includes a third capacitor C411, a fourth capacitor C412, and a second inductance L52; the first end of the third capacitor C411 is connected to the second end of the second 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.

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 an output node of the first matching network 31. In this embodiment, 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, and the second end of the second capacitor C312 is grounded, so that when the operation mode of the push-pull power amplifying circuit is the first mode, the first capacitor C311, the second capacitor C312 and the first inductor L51 participate in the output impedance matching of the push-pull power amplifying circuit, so as to flexibly adjust the output impedance of the push-pull power amplifying circuit.

In a specific embodiment, the second matching network 41 includes a third capacitor C411, a fourth capacitor C412, and a second inductor L52; the first end of the third capacitor C411 is connected to the second end of the second 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. In this embodiment, by connecting the first end of the third capacitor C411 to the second end of the second 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, and the second end of the fourth capacitor C412 is grounded, when the operation mode of the push-pull power amplifying circuit is the first mode, the third capacitor C411, the fourth capacitor C412 and the second inductor L52 participate in the output impedance matching of the push-pull power amplifying circuit, so as to flexibly adjust the output impedance of the push-pull power amplifying circuit.

In one embodiment, as shown in fig. 5, the push-pull power amplifying circuit further includes an adjustable capacitor Ct; the primary winding comprises a first primary coil section and a second primary coil section; a first end of the first primary coil section is coupled to the output end of the first power amplifier M1, and a second end of the first primary coil section is connected with a first end of the adjustable capacitor Ct; the first end of the second primary coil section is coupled to the output of the second power amplifier M2, and the second end of the second primary coil section is connected to the second end of the adjustable capacitance Ct.

In a specific embodiment, a first end of the first primary coil section is coupled to the output terminal of the first power amplifier M1, a second end of the first primary coil section is connected to a first end of the adjustable capacitance Ct, a first end of the second primary coil section is coupled to the output terminal of the second power amplifier M2, and a second end of the second primary coil section is connected to a second end of the adjustable capacitance 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 amplifying circuit.

In this 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, and 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, so as to flexibly adjust the capacitance value of the adjustable capacitor Ct according to the operating frequency band of the push-pull power amplifying circuit, and flexibly perform impedance matching on the push-pull power amplifying circuit.

Optionally, the push-pull power amplifying circuit further comprises a first matching inductance L81 and a second matching inductance L82. The first end of the first matching inductor L81 is connected with the output end of the first power amplifier M1, the second end of the first matching inductor L81 is connected with the first end of the first primary coil section, the first end of the second matching inductor L82 is connected with the output end of the second power amplifier M2, the second end of the second matching inductor L82 is connected with the first end of the second primary coil section, and the first matching inductor L81 and the second matching inductor L82 are used for participating in impedance matching of the push-pull power amplifying circuit. In a specific embodiment, the first matching inductance L81 may be implemented by a transmission line between the output terminal of the first power amplifier M1 and the first terminal of the first primary coil section. The second matching inductance L82 may be implemented by a transmission line between the output of the second power amplifier M2 and the first end of the second primary coil section.

Optionally, the push-pull power amplifying circuit further includes a harmonic suppression capacitor C81, a first end of the harmonic suppression capacitor C81 is connected to the output terminal of the first power amplifier M1, and a second end of the harmonic suppression capacitor C81 is connected to the output terminal of the second power amplifier M2, and is configured to suppress an odd harmonic signal of the push-pull power amplifying circuit.

In one embodiment, as shown in fig. 5, the push-pull power amplification circuit further includes a first switchable harmonic rejection circuit 60 and a second switchable harmonic rejection circuit 70; a first end of the first switchable harmonic rejection circuit 60 is connected to a first input of the first balun 20, and a second end of the first switchable harmonic rejection circuit 60 is grounded; a first end of the second switchable harmonic rejection circuit 70 is connected to a second input of the first balun 20, and a second end of the second switchable harmonic rejection circuit 70 is grounded; the capacitance presented by the first switchable harmonic rejection circuit 60 and the capacitance presented by the second switchable harmonic rejection circuit 70 are inversely related to the operating frequency band of the push-pull power amplifying circuit.

In a specific embodiment, a first terminal of the first switchable harmonic rejection circuit 60 is connected to a first input terminal of the first balun 20, and a second terminal of the first switchable harmonic rejection circuit 60 is grounded and configured to reject even harmonic signals of the push-pull power amplifying circuit.

Alternatively, the even harmonic signal may be one of a second harmonic signal, a fourth harmonic signal, or a sixth harmonic signal. Preferably, the harmonic component of the second harmonic signal is the largest among the even harmonic signals in the push-pull power amplifying circuit, and therefore, the even harmonic signal is preferably the second harmonic signal.

In a specific embodiment, a first terminal of the second switchable harmonic rejection circuit 70 is connected to the second input terminal of the first balun 20, and a second terminal of the second switchable harmonic rejection circuit 70 is grounded and configured to reject even harmonic signals of the push-pull power amplifying circuit.

Preferably, the first switchable harmonic rejection circuit 60 and the second switchable harmonic rejection circuit 70 are different to reject different even harmonic signals.

Note that the specific circuit configuration and the configuration of the resonance frequency point of the first switchable harmonic suppression circuit 60 and the second switchable harmonic suppression circuit 70 are similar to those of the third switchable harmonic suppression circuit in the above-described embodiment, for example, C61, C62, L61, and S61 in the first switchable harmonic suppression circuit 60 in fig. 5, and C71, C72, L71, and S71 in the second switchable harmonic suppression circuit 70, which are not described here again.

In one embodiment, when the push-pull power amplifying circuit operates in the first frequency band, the first rf output signal is output through the first output matching circuit 30; when the push-pull power amplifying circuit operates in the second frequency band, the second output matching circuit 40 outputs a second radio frequency output signal, and the first frequency band is larger than the second frequency band.

In a specific embodiment, when the push-pull power amplifying circuit works in a high frequency band, the first output matching circuit 30 outputs a first radio frequency output signal, and when the push-pull power amplifying circuit works in an intermediate frequency band, the second output matching circuit 40 outputs a second radio frequency output signal, so that impedance matching of the push-pull power amplifying circuit in different working frequency bands is realized, and the bandwidth performance of the push-pull power amplifying circuit is optimized.

In an embodiment, the primary winding is coupled to the first secondary coil section less than the primary winding is coupled to the second secondary coil section.

In a specific embodiment, the degree of coupling of the primary winding to the first secondary coil section is the same as the degree of coupling of the primary winding to the second secondary coil section, in the case where the primary winding is coupled to the first secondary coil section and the primary winding is coupled to the second secondary coil section. However, in the practical application process, when the coupling mode of the primary winding and the first secondary coil section is the same as the coupling mode of the primary winding and the second secondary coil section, that is, when the coupling degree of the primary winding and the first secondary coil section is the same as the coupling degree of the primary winding and the second secondary coil section, if the radio frequency signals in different frequency bands are converted respectively, the coupling degree of the primary winding and the first secondary coil section is different from the coupling degree of the primary winding and the second secondary coil section. For example, the coupling degree of the primary winding and the first secondary coil section is larger than that of the primary winding and the second secondary coil section when the primary winding is used for converting the radio frequency signals in the high frequency range, so that the coupling degree of the primary winding and the first secondary coil section is unbalanced with that of the primary winding and the second secondary coil section when the primary winding and the second secondary coil section are used for converting the radio frequency signals in the low frequency range. Therefore, in this embodiment, the coupling degree of the primary winding outputting the first rf output signal and the first secondary coil section is made smaller than the coupling degree of the primary winding outputting the second rf output signal and the second secondary coil section, so as to balance the coupling degree of the primary winding and the first secondary coil section, and the coupling degree of the primary winding and the second secondary coil section under different rf signals.

In one embodiment, the first balun 20 is applied on a substrate, and the substrate comprises a first metal layer and a second metal layer which are adjacently arranged; the first secondary coil section is arranged on the first metal layer, and the second secondary coil section is arranged on the second metal layer; the primary winding of the first balun 20 is coupled to the first secondary coil section in layers and the primary winding of the first balun 20 is coupled to the second secondary coil section in layers.

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

It should be noted that, in this embodiment, only the primary winding of the first balun 20 is coupled to the first secondary coil section in upper and lower layers, and the primary winding is coupled to the second secondary coil section in the same layer, which is taken as an exemplary illustration, and any other implementation manner that can change the coupling degree between the primary winding and the first secondary coil section and the coupling degree between the primary winding and the second secondary coil section is included, but not limited thereto.

The above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention, and are intended to be included in the scope of the present invention.

Claims

1. The push-pull power amplifying circuit is characterized by comprising a differential amplifying circuit, a first balun, a first output matching circuit and a second output matching circuit; the differential amplifying circuit comprises a first power amplifier and a second power amplifier; the first balun includes a primary winding and a secondary winding; the secondary winding comprises a first secondary coil section and a second secondary coil section;

2. The push-pull power amplification circuit of claim 1, wherein when an operation mode of the push-pull power amplification circuit is a first mode, the first output matching circuit and a portion of the second output matching circuit participate in output impedance matching of the push-pull power amplification circuit together;

3. The push-pull power amplification circuit of claim 1 wherein the first output matching circuit comprises a first switch and a first matching network; a first end of the first matching network is connected with a first end of the first secondary coil section, and a second end of the first matching network is grounded; the third end of the first matching network is connected with the first end of the first change-over switch; when the working mode of the push-pull power amplifying circuit is a second mode, the first switch is turned off, and the second output matching circuit and the first matching network participate in output impedance matching of the push-pull power amplifying circuit together;

4. The push-pull power amplification circuit of claim 3 wherein the first matching network comprises a second capacitor, a first end of the second capacitor being connected to a first end of the first switch, a second end of the second capacitor being grounded; the first output matching circuit further comprises a fifth capacitor, and one end of the fifth capacitor is connected with the second end of the first change-over switch; the second end of the fifth capacitor is grounded;

5. The push-pull power amplification circuit of claim 4, wherein the first matching network further comprises a first capacitor, a first end of the first capacitor being connected to a first end of the first secondary winding segment, a second end of the first capacitor being connected to a first end of the first switch and a first end of the first diode; the second matching network further comprises a third capacitor, a first end of the third capacitor is connected with the first end of the second secondary coil section, and a second end of the third capacitor is connected with the first end of the second change-over switch and the first end of the fourth capacitor.

6. The push-pull power amplification circuit of claim 4, further comprising an adjustment matching circuit; the adjusting and matching circuit is arranged between the differential amplifying circuit and the first balun; the adjustment matching circuit is configured to impedance match the push-pull power amplification circuit based on an operating mode of the push-pull power amplification circuit.

7. The push-pull power amplification circuit of claim 1 wherein the first output matching circuit comprises a first switch and a first matching network; the first end of the first change-over switch is connected with the first end of the first secondary coil section, and the second end of the first change-over switch is connected with the first matching network;

8. The push-pull power amplification circuit of claim 7, wherein the first matching network comprises a first capacitor, a second capacitor, and a first inductor; the first end of the first capacitor is connected with the second end of the first change-over switch, the second end of the first capacitor is connected with 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;

9. The push-pull power amplification circuit of claim 7, wherein the push-pull power amplification circuit further comprises an adjustable capacitor; the primary winding includes a first primary coil section and a second primary coil section;

10. The push-pull power amplification circuit of claim 1, further comprising a first switchable harmonic rejection circuit and a second switchable harmonic rejection circuit;

11. The push-pull power amplification circuit of claim 1 wherein a first radio frequency output signal is output by the first output matching circuit when the push-pull power amplification circuit is operating in a first frequency band; when the push-pull power amplifying circuit works in a second frequency band, a second radio frequency output signal is output through the second output matching circuit, and the first frequency band is larger than the second frequency band.

12. The push-pull power amplification circuit of claim 11, wherein a degree of coupling of the primary winding to the first secondary coil segment is less than a degree of coupling of the primary winding to the second secondary coil segment.

13. The push-pull power amplification circuit of claim 12, wherein the first balun is applied on a substrate comprising a first metal layer and a second metal layer disposed adjacent to each other; the first secondary coil section is arranged on the first metal layer, and the second secondary coil section is arranged on the second metal layer; the primary winding of the first balun is coupled to the first secondary coil section in a same layer, and the primary winding of the first balun is coupled to the second secondary coil section in upper and lower layers.