WO2023179244A1 - Push-pull power amplifier circuit - Google Patents

Abstract

Disclosed in the present application is a push-pull power amplifier circuit. The push-pull power amplifier circuit comprises a differential amplifier circuit, a first balun, a first output matching circuit and a second output matching circuit. A secondary winding of the first balun comprises a first secondary coil segment and a second secondary coil segment; a first end of a primary winding is connected to an output end of a first power amplifier, and a second end of the primary winding is connected to an output end of a second power amplifier; a first end of the first secondary coil segment is connected to the first output matching circuit, and a second end of the first secondary coil segment is grounded; a first end of the second secondary coil segment is connected to the second output matching circuit, and a second end of the second secondary coil segment is grounded; when an operation mode of the push-pull power amplifier circuit is a first mode, the first output matching circuit outputs a first radio-frequency output signal; and when the operation mode of the push-pull power amplifier circuit is a second mode, the second output matching circuit outputs a second radio-frequency output signal. The present technical solution can optimize the bandwidth performance of the push-pull power amplifier circuit.

Description

Push-pull power amplifier circuit

This application is based on the Chinese invention application with application number 202210289653.0 and titled "Push-pull power amplifier circuit" submitted on March 23, 2022, and claims priority.

Technical field

The present application relates to the field of radio frequency technology, and in particular to a push-pull power amplifier circuit.

Background technique

The key performance goal 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 higher-frequency, larger operating bandwidth, and higher-order QAM modulation RF front-ends, making it challenging for RF front-ends. The design of power amplifiers puts forward more stringent requirements.

However, when designing a push-pull power amplifier circuit, the operating bandwidth performance of the push-pull power amplifier circuit is ignored for the sake of other performance of the push-pull power amplifier circuit (such as design requirements or performance indicators such as high frequency or high power). Therefore, while ensuring the overall performance of the push-pull power amplifier circuit, how to improve the operating bandwidth of the push-pull power amplifier circuit has become an urgent problem to be solved.

Application content

Embodiments of the present application provide a push-pull power amplifier circuit to solve the problem of poor bandwidth performance of the push-pull power amplifier circuit.

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 The 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 section One end is connected to the first output matching circuit, the second end of the first secondary coil section is connected to ground; the first end of the second secondary coil section is connected to the second output matching circuit, the The second end of the second secondary coil section is grounded;

When the working mode of the push-pull power amplifier circuit is the first mode, the 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, the first radio frequency output signal is output through the first output matching circuit. The second output matching circuit outputs a second radio frequency output signal.

Further, when the working mode of the push-pull power amplifier circuit is the first mode, the first output matches The 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 operating 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. .

Further, the first output matching circuit includes a first 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 section, and the first The second end of the matching network is grounded; the third end of the first matching network is connected to the first end of the first switch; when the working mode of the push-pull power amplifier circuit is the second mode, the The first switch is turned off, 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 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 section, and the second matching network 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 switch; when the working mode of the push-pull power amplifier circuit is the first mode, the The second switching switch is turned off, 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.

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

The second matching network 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 connected to ground; the second output matching The circuit also includes a sixth capacitor, 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 ground.

Further, the first matching network further includes a first capacitor, the first end of the first capacitor is connected to the first end of the first secondary coil section, and the second end of the first capacitor is connected to the first end of the first secondary coil section. The first end of the first switch is connected to the first end of the first and second capacitors; the second matching network also includes a third capacitor, the first end of the third capacitor is connected to the second secondary The first end of the coil section is connected, and the second end of the third capacitor is connected to the first end of the second switch and the first end of the fourth capacitor.

Further, the push-pull power amplifier circuit further includes an adjustment matching circuit; the adjustment matching circuit is disposed between the differential amplifier circuit and the first balun; the adjustment matching circuit is configured to The working mode of the pull-pull power amplifier circuit is to perform impedance matching on the push-pull power amplifier circuit.

Further, the first output matching circuit includes a first switching switch and a first matching network; the first end of the first switching switch is connected to the first end of the first secondary coil section, and the first The second end of the switch is connected to the first matching network;

The second output matching circuit includes a second switch and a second matching network; the first end of the second switch is connected to the first end of the second secondary coil section, and the second end of the second switch is The second end matches the second network connection;

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 When , the first switch is turned off and the second switch is turned on.

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, and the first end of the first capacitor is The second terminal is connected to the first terminal of the second capacitor and the first terminal of the first inductor. The second terminal of the second capacitor is connected to ground. The second terminal of the first inductor is the first matching network. The output node;

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, and the second end of the third capacitor The first end of the fourth capacitor is connected to the first end of the second inductor, the second end of the fourth capacitor is connected to ground, and the second end of the second inductor is the second end of the second matching network. Output node.

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

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

The first end of the second primary coil section is coupled to the output end of the second power amplifier, and the second end of the second primary coil section is connected to the second end of the adjustable capacitor.

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

The first end of the first switchable harmonic suppression circuit is connected to the first input end of the first balun, and the second end of the first switchable harmonic suppression circuit is connected to ground;

The first end of the second switchable harmonic suppression circuit is connected to the second input end of the first balun, and the second end of the second switchable harmonic suppression circuit is connected to ground;

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.

Further, when the push-pull power amplifier circuit operates in the first frequency band, the first radio frequency output signal is output through the first output matching circuit; when the push-pull power amplifier circuit operates in the second frequency band, the first radio frequency output signal is output through the first output matching circuit. The second output matching circuit outputs a second radio frequency output signal, and the first frequency band is greater than the second frequency band.

Further, the coupling degree between the primary winding and the first secondary coil section is smaller than the coupling degree between the primary winding and the second secondary coil section.

Further, the first balun is applied to a substrate, and the substrate includes a first metal layer and a second metal layer that are adjacently arranged; the first secondary coil segment is arranged on the first metal layer, so The second secondary coil section is located at The second metal layer; the primary winding of the first balun and the first secondary coil section are coupled in the same layer, and the primary winding of the first balun and the second secondary coil section are on the upper and lower layers. coupling.

The above-mentioned 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 consists of primary and secondary windings. 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, 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 section is connected to the first output matching circuit, The second end of the first secondary coil section is connected to the ground; the first end of the second secondary coil section is connected to the second output matching circuit, and the second end of the second secondary coil section is connected to the ground. In this embodiment, by connecting the first end of the first secondary coil section 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 ground. Connected to the second output matching circuit, the second end of the second secondary coil section 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. When the operating mode of the pull-pull power amplifier circuit is the second mode, the second radio frequency output signal is output through the second output matching circuit, thereby achieving the purpose of switching between different operating modes in a push-pull power amplifier circuit, and ensuring The output impedance of the push-pull power amplifier circuit is matched in different operating modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

Description of the drawings

In order to explain the technical solutions of the embodiments of the present application more clearly, the drawings needed to be used in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. , for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative labor.

Figure 1 is a circuit schematic diagram of a push-pull power amplifier circuit in an embodiment of the present application;

Figure 2 is another circuit schematic diagram of a push-pull power amplifier circuit in an embodiment of the present application;

Figure 3 is another circuit schematic diagram of a push-pull power amplifier circuit in an embodiment of the present application;

Figure 4 is another circuit schematic diagram of a push-pull power amplifier circuit in an embodiment of the present application;

FIG. 5 is another circuit schematic diagram of a push-pull power amplifier circuit in an embodiment of the present application.

In the picture:
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 ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

It will be understood that the application may be embodied in different 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 application to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity, like reference numerals refer to the same elements throughout.

It will be understood that when an element or layer is referred to as being "on," "adjacent," "connected to" or "coupled to" another element or layer, it can be directly on, with, or coupled to the other element or layer. They may be adjacent, connected, or coupled to other elements or layers, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly adjacent," "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 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 application.

Spatial relational terms such as "under", "under", "under", "under", "on", "above", etc. may be used here for convenience of description This describes the relationship of one element or feature to other elements or features 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, then elements or features described as "below" or "under" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary terms "below" and "under" may include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatial 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 application. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It will also be understood that the terms "consisting of" and/or "comprising", when used in this specification, identify the presence of stated features, integers, steps, operations, elements and/or parts but do not exclude one or more others The presence or addition of features, integers, steps, operations, elements, parts, and/or groups. When used herein, the term "and/or" includes any and all combinations of the associated listed items.

In order to fully understand this application, detailed structures and steps will be proposed in the following description to explain this application. proposed technical solutions. The preferred embodiments of the present application are described in detail below. However, in addition to these detailed descriptions, the present application may also have other implementations.

This embodiment provides a push-pull power amplifier circuit, as shown in Figure 1, including 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 A 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 and the second The output end of a power amplifier M1 is connected, 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 section is connected to the first output matching circuit 30, and the first secondary coil section The second end of the second 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; the working mode of the push-pull power amplifier circuit is the first When the push-pull power amplifier circuit is in the second mode, the first radio frequency output signal is output through the first output matching circuit 30; when the push-pull power amplifier circuit operates in the second mode, the second radio frequency output signal is output through the second output matching circuit 40.

Among them, the push-pull power amplifier circuit can work in different working modes. For example, the working mode may be the working frequency band of the push-pull power amplifier circuit, or the power mode of the push-pull power amplifier circuit, etc. For example: when the push-pull power amplifier circuit works in different operating frequency bands, the operating frequency band can be a high frequency band, a medium frequency band or a low frequency band. When the push-pull power amplifier circuit operates in different power modes, the power mode may be a high power mode (HPM) or a low power mode (LPM).

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 among high frequency band, medium frequency band or low frequency band.

In a specific embodiment, the push-pull power amplification circuit includes a differential amplification circuit 10. The differential amplification circuit 10 is configured to amplify two radio frequency signals of equal magnitude and opposite phase.

As an example, two radio frequency signals with equal magnitude and opposite phase include a first radio frequency input signal and a second radio frequency 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 radio frequency input signal and output a first radio frequency amplified signal. The second power amplifier M2 is configured to amplify the second radio frequency input signal and output a second radio frequency amplified signal. Alternatively, the first power amplifier M1 and the second power amplifier M2 may be BJT transistors (eg, 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 front-end circuit of the differential amplifier circuit 10 . Optionally, the pre-stage circuit includes a second balun. Exemplarily, the first input end of the second balun is configured to receive the first radio frequency signal, the second input end of the second balun is grounded, and the first output end of the second balun is connected to the first power amplifier The input terminal of M1 is connected, the second output terminal of the second balun is connected to the input terminal of the second power amplifier M2, the second balun is configured to convert the first radio frequency signal into a first radio frequency input signal and a second a radio frequency input signal, and output the first radio frequency input signal to the first power amplifier M1 to amplify the first power The device M1 amplifies the first radio frequency input signal and outputs the second radio frequency input signal to the second power amplifier M2, so that the second power amplifier M2 amplifies the second radio frequency input signal.

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 radio frequency amplified signal output by 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 , is configured to receive the second radio frequency amplified signal output by the second power amplifier M2, the first end of the first secondary coil section is connected to the first output matching circuit 30, and the second end of the first secondary coil section 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 section are coupled to each other, and the first radio frequency amplified signal and the second radio frequency amplified signal are synthesized and converted through the first output matching circuit 30 Output the first radio frequency output signal. When the working mode of the push-pull power amplifier circuit is the second mode, the primary winding and the second secondary coil section are coupled to each other, and the first radio frequency amplified signal and the second radio frequency amplified signal are synthesized and converted through the second output matching circuit 40 Output a second radio frequency output signal. In this embodiment, when the working mode of the push-pull power amplifier circuit is the first mode, the first radio frequency 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 radio frequency output signal is output through the second output matching circuit 40, thereby achieving the purpose of switching between different working modes in one push-pull power amplifier circuit, and ensuring the output of the push-pull power amplifier circuit in different working modes. Impedance matching, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

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 the input first radio frequency input signal. The collector of the first power amplifier M1 The electrode 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 the input For the second radio frequency 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.

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, 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 section is connected to the first output matching circuit 30 is connected, the second end of the first secondary coil section is connected to the ground; 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 connected to the ground. In this embodiment, by connecting the first end of the first secondary coil section to the first output matching circuit 30, 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 ground. The second terminal of the second secondary coil section is connected to the second output matching circuit 40, and the second terminal of the second secondary coil section is connected to the ground. When the operating 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. , the push-pull power When the working mode of the 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 that the push-pull The output impedance matching of the pull-pull power amplifier circuit in different operating modes is used to optimize the bandwidth performance of the push-pull power amplifier circuit.

In one embodiment, when the operating 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 operating 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.

In a specific embodiment, the first end of the first secondary coil section is connected to the first output matching circuit 30, the second end of the first secondary coil section is grounded, and the second end of the second secondary coil section is connected to the ground. The first end is connected to the second output matching circuit 40, the second end of the second secondary coil section is connected to the ground, and some components (for example, capacitors) in the first output matching circuit 30 are connected to the ground end, and Connect certain components (for example, capacitors) in the second output matching circuit 40 to the ground terminal, thereby ensuring that the second secondary coil section is connected to part of the second secondary coil section when the operating mode of the push-pull power amplifier circuit is the first mode. The 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 push-pull power amplification in the first mode of operation. The circuit is impedance matched. When the working mode of the push-pull power amplifier circuit is the second mode, it is ensured that the first secondary coil section 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 They jointly participate in the output impedance matching of the push-pull power amplifier circuit, so as to facilitate the impedance matching of the push-pull power amplifier circuit whose working mode is the first mode.

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, thereby achieving push-pull power. When the amplifier circuit operates in different operating modes, both the first output matching circuit 30 and the second output matching circuit 40 can jointly participate in impedance matching, thereby improving the flexibility of achieving output impedance matching in different operating modes and ensuring push-pull The output impedance of the power amplifier circuit is matched in different operating modes, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

In one embodiment, as shown in Figure 1, the first output matching circuit 30 includes a first switch S311 and a first matching network 31; the first end of the first matching network 31 and the first end of the first secondary coil section The second end of the first matching network 31 is connected to the ground; the third end of the first matching network 31 is connected to the first end of the first switch S311. The second output matching circuit 40 includes a second 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 section, and the second end of the second matching network 41 Grounded, the third terminal of the second matching network 41 is connected to the first terminal of the second switch S411.

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 S311 is turned on. The switch S411 is turned off. 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, the working mode of the push-pull power amplifier circuit is: In 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, thereby improving the flexibility of achieving output impedance matching in the first operating 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 provided between the first switch S311 and the first secondary coil between the first ends of the segments and connected to the ground end. Therefore, when the operating 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 push-pull power amplifier circuit. output impedance matching.

In a specific embodiment, the first output matching circuit 30 includes a first 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 section. The second end of the 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 the output node of the first output matching circuit 30 and is configured to When the working mode of the push-pull power amplifier circuit is the first mode, the first radio frequency output signal is output. The second output matching circuit 40 includes a second 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 section, and the second end of the second matching network 41 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 the output node of the second output matching circuit 40, and is configured to operate in the push-pull power amplifier circuit. When the mode is the second mode, the second radio frequency output signal is output.

In this embodiment, when the operating mode of the push-pull power amplifier circuit is the first mode, for example, when the operating frequency band of the push-pull power amplifier circuit is the intermediate frequency band, the first switch S311 is turned on, and the second switch S311 is turned on. The switch S411 is turned off, so that the second secondary coil section and the second matching network 41 form a ground loop, so that 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, This improves the flexibility of impedance adjustment when the push-pull power amplifier circuit operates in the mid-frequency band mode. When the operating mode of the push-pull power amplifier circuit is the second mode, for example, when the operating frequency band of the push-pull power amplifier circuit is a high-frequency band, the first switch S311 is turned off and the second switch S411 is turned on, As a result, the first secondary coil section and the first matching network 31 form a ground loop, and 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, thereby improving the push-pull power. The flexibility of impedance adjustment when the amplifier circuit is working in high-frequency mode can achieve the purpose of switching between different working modes in a push-pull power amplifier circuit, and ensure that the push-pull power amplifier circuit can operate in different working modes. The output impedance is matched to optimize the bandwidth performance of the push-pull power amplifier circuit.

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.

Preferably, since the impedances of the first secondary coil section and the second secondary coil section in the first balun 20 are inductive, the first matching network 31 and the first matching network 31 formed by capacitors connected in parallel and/or in series are selected. Two matching networks 41, namely Making the first matching network 31 and the second matching network 41 capacitive facilitates adjusting the output impedance of the push-pull power amplifier circuit to achieve output impedance matching of the push-pull power amplifier circuit.

The first matching network 31 includes a second capacitor, a first end of the second capacitor is connected to a first end of the first switch, and a second end of the second capacitor is grounded; the first switch The second end of the switch is the 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 connected to ground, and the second capacitor and the fifth capacitor can be connected to different grounds respectively, or they can 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 a first end of the second switch, and a second end of the fourth capacitor is grounded; the second switch The second end of the 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 connected to ground, and the second capacitor and the fifth capacitor can be connected to different grounds respectively, or they can be connected to the same ground.

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. At this time, the second output matching circuit 40 to ground The capacitance value of the capacitor is not likely 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. At this time, the capacitance value of the capacitor to ground in the second output matching circuit 40 needs to be compared. is too big. 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. At this time, the capacitance of the first output matching circuit 30 to the ground capacitance The value 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. At this time, the capacitance to ground in the first output matching circuit 30 The capacitor value needs to be larger.

To this end, this application connects the first end of the second capacitor to the first end of the first switch, and the second end of the second capacitor is grounded; the second end of the first switch The terminal is the output node of the first matching network 31, one terminal of the fifth capacitor is connected to the second terminal of the first switch; the second terminal of the fifth capacitor is connected to the third terminal of the second capacitor. The two ends are connected, and the first end of the fourth capacitor is connected to the first end of the second switch, and the second end of the second switch is the output node of the second matching network 41, 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. It can be seen that when the push-pull When the working mode of the power amplifier circuit is the first mode, the first 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 ground capacitance. To participate in impedance matching, since the second switch is turned off, only the fourth capacitor in the second output matching circuit 40 forms a smaller capacitance to ground to participate in impedance matching. When the working mode of the push-pull power amplifier 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 relatively small capacitor. A large capacitance to ground participates in impedance matching. Since the first switch is turned off, only the fourth capacitor in the first output matching circuit 30 forms a smaller capacitance to ground to participate in impedance matching. From The output impedance of the push-pull power amplifier circuit can be flexibly adjusted to achieve impedance matching.

In one embodiment, as shown in FIG. 1 , 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 section. The second terminal of a capacitor C311 is connected to the first terminal of the first switch S311 and the first terminal of the second capacitor C312. The second terminal of the second capacitor C312 is connected to the ground. The second terminal of the first switch S311 is the first terminal of the first switch S311. Output node of matching network 31.

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 section. The second end of the third capacitor C411 is connected to the second switch. The first end of S411 is connected to the first end of the fourth capacitor C412, and the second end of the fourth capacitor C412 is connected to ground; the second end of the second switch S411 is the output node of the second matching network 41.

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; 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; the second end of the sixth capacitor C413 is connected to the second end 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 section, 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 terminal of the second capacitor C312 is connected to the ground, and the second terminal of the first switch S311 is the 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. The first end of the third capacitor C411 is connected to the first end of the second secondary coil section, and the third capacitor C411 has a first end connected to the first end of the second secondary coil section. The two terminals are connected to the first terminal of the second switch S411 and the first terminal of the fourth capacitor C412, and the second terminal of the fourth capacitor C412 is connected to ground; the second terminal of the second switch S411 is the output of the second matching network 41 node.

In the above circuit structure, when the operating frequency band of the push-pull power amplifier circuit is the first frequency band (for example, high frequency band), the first switch S311 is turned on, and the second switch S411 is turned off, so that the second switch S311 is turned on. The secondary coil section, the third capacitor C411 and the fourth capacitor C412 form a ground loop, so that the first output matching circuit 30 and the second secondary coil section, the third capacitor C411 and the fourth capacitor C412 jointly participate in the push-pull power amplifier circuit output impedance matching. 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 switch S311 is turned off and the second switch S411 is turned on, so that the first secondary coil section is connected to the second The first capacitor C311 and the second capacitor C312 form a ground loop, so that the second output matching circuit 40 and the second secondary coil section, the first capacitor C311 and the second capacitor C312 jointly participate in the output impedance matching of the push-pull power amplifier circuit, thereby This achieves the purpose of switching between different working modes in a 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.

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. The fifth capacitor C313 has a third end connected to the second end of the first switch S311. Two terminals and the second terminal Connect the second end of C312. The second output matching circuit 40 further 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 operating frequency band of the push-pull power amplifier circuit is the first frequency band, the first switch S311 is turned off, the second switch S411 is turned on, and the third capacitor C411, The fourth capacitor C412 and the sixth capacitor C413, as well as the second secondary coil section, 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 working frequency band of the push-pull power amplifier 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 first capacitor C312 in the first output matching circuit 30 The five capacitors C313, as well as the second secondary coil section, the third capacitor C411 and the fourth capacitor C412 jointly participate in the output impedance matching of the push-pull power amplifier circuit.

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 to 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, while the third capacitor C411 and the fourth capacitor C412 play the role of impedance matching. The role of auxiliary adjustment. Therefore, when the working frequency band of the push-pull power amplifier circuit is the first frequency band, the first switch S311 is turned off, the second switch S411 is turned on, and the fourth capacitor C412 and the sixth capacitor C413 are connected in parallel to provide a larger capacitance. value, and is assisted by the first capacitor C311 and the second capacitor C312 for impedance matching. When the operating frequency band of the push-pull power amplifier circuit is the second frequency band, the first switch S311 is turned on, and 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 are assisted by the third capacitor C411 and the fourth capacitor C412 for impedance matching to more flexibly adjust the output impedance of the push-pull power amplifier circuit.

In one embodiment, as shown in Figure 3, the push-pull power amplifier circuit further includes an adjustment matching circuit 50; the adjustment matching circuit 50 is disposed between the differential amplifier circuit 10 and the first balun 20; the adjustment matching circuit 50 is configured as Based on the working mode of the push-pull power amplifier circuit, impedance matching is performed on the push-pull power amplifier circuit.

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 operating frequency band of the push-pull power amplifier 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, the first end of the first inductor L51 adjustment circuit is connected to the output end of the first power amplifier M1, and the second end of the first inductor L51 adjustment circuit is connected to the first end of the primary winding and the first end of the first capacitance adjustment circuit. One end is connected, and the first inductor L51 adjustment circuit is configured to switch the inductor value based on the working mode of the push-pull power amplifier circuit.

As an example, the first end of the second inductor L52 adjustment circuit is connected to the output end of the second power amplifier M2, and the second end of the second inductor L52 adjustment circuit is connected to the second end of the primary winding and the second capacitor C312 adjustment circuit. The second end is connected, and the second inductor L52 adjustment circuit is configured to switch the inductor value based on the working mode of the push-pull power amplifier circuit. .

As an example. The first capacitance adjustment circuit is configured to switch the capacitance value based on the operating mode of the push-pull power amplifier circuit.

Optionally, as shown in FIG. 4 , the first inductor L51 adjustment circuit includes a first inductor L51 and a third switch S51 connected in parallel. The second inductance L52 adjustment circuit includes a second inductor L52 and a fourth switch S52 connected in parallel; the first capacitance adjustment circuit includes a seventh capacitor C51 and a fifth switch S53 connected in series.

In this embodiment, when the working frequency band of the push-pull power amplifier 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, and the first inductor L51 and the second inductor L52 are connected. 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 working frequency band of the push-pull power amplifier 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 disconnected to perform impedance matching on the fundamental wave signal corresponding to the first frequency band. The first frequency band is larger than the second frequency band.

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.

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 amplifier circuit, the harmonic component of the third harmonic signal is the largest. Therefore, the odd harmonic signal is preferably a third harmonic signal.

Optionally, as shown in Figure 4, the third switchable harmonic suppression circuit includes a third inductor L53, an eighth capacitor C52, a ninth capacitor C53 and a sixth switch S54; the first end of the third inductor L53 is connected to the first The output end of the power amplifier M1 is connected to the first end of the adjustment circuit of the first inductor L51, and the 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 eighth capacitor The second end of C52 is connected to the output end of the second power amplifier M2 and the first end of the second inductor L52 adjustment circuit; the second end of the sixth switch S54 is connected to the first end of the ninth capacitor C53, and the ninth capacitor C53 The second terminal is connected to the second terminal of the eighth capacitor C52.

When the working mode of the push-pull power amplifier 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 working mode of the push-pull power amplifier 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 increases. The three inductors L53 and the parallel-connected eighth capacitor C52 and ninth capacitor C53 form a resonant circuit to suppress odd harmonic signals of the push-pull power amplifier circuit. Among them, the first frequency band is larger than the second frequency band.

According to the resonant frequency formula: Among them, 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 working frequency band of the push-pull power amplifier circuit is larger, the odd harmonic signal of the push-pull power amplifier circuit will The larger the component, the larger the resonant frequency point of the third switchable harmonic suppression circuit, so as to suppress odd harmonic signals. Since the inductance value L of the third inductor L53 remains unchanged, the resonant frequency of the third switchable harmonic suppression circuit The larger the rate point f is, the smaller the capacitance value C of the third switchable harmonic suppression circuit is. The smaller the resonant frequency point f of the third switchable harmonic suppression circuit is, the smaller the capacitance value C of the third switchable harmonic suppression circuit is. The capacitance value C needs to be larger. Therefore, in this embodiment, when the working mode of the push-pull power amplifier circuit is the first mode, the sixth switch S54 is turned off, and only the eighth capacitor C52 is connected to the circuit, reducing The capacitance value presented by the small third switchable harmonic suppression circuit, when the working mode of the push-pull power amplifier circuit is the second mode, causes the sixth switch S54 to be turned on, the eighth capacitor C52 and the ninth capacitor C53 are connected in parallel, and the third The capacitance value presented by the switchable harmonic suppression circuit increases, thereby flexibly adjusting the resonance frequency point of the third switchable harmonic suppression circuit to suppress odd harmonic signals in different operating frequency bands and optimizing the bandwidth of the push-pull power amplifier circuit. performance.

In one embodiment, the first output matching circuit 30 includes a switch and a switchable network. 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 switches 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 between different working modes in one push-pull power amplifier circuit. And it 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.

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 terminal of the first capacitor C311 is connected to the second terminal of the first switch S311. terminals are connected, the second terminal of the first capacitor C311 is connected to the first terminal of the second capacitor C312 and the first terminal of the first inductor L51, the second terminal of the second capacitor C312 is connected to ground, and the second terminal 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 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 connected to ground. The second end of the second inductor L52 is the second matching The output node of 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, and the first end of the first capacitor C311 is connected to the second end of the first switch S311. The second end of the 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 connected to ground. The second end of the first inductor L51 is the first matching network 31 output node. In this embodiment, by connecting the first terminal of the first capacitor C311 to the second terminal of the first switch S311, the second terminal of the first capacitor C311 is connected to the first terminal of the second capacitor C312 and the first inductor. The first terminal of L51 is connected, and the second terminal of the second capacitor C312 is connected to the ground. When the working mode of the push-pull power amplifier circuit is the first mode, the first capacitor C311, the second capacitor C312 and the first inductor L51 can participate in the push-pull power amplifier circuit. The output impedance of the push-pull power amplifier circuit is matched to flexibly adjust the output impedance of the push-pull power amplifier 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, and the third Capacitor C411 The second terminal is connected to the first terminal of the fourth capacitor C412 and the first terminal of the second inductor L52. The second terminal of the fourth capacitor C412 is connected to ground. The second terminal of the second inductor L52 is the output node of the second matching network 41. . In this embodiment, by connecting the first terminal of the third capacitor C411 to the second terminal of the second switch S411, the second terminal of the third capacitor C411 is connected to the first terminal of the fourth capacitor C412 and the second inductor L52. The first end of the fourth capacitor C412 is connected to the ground, so that when the working mode of the push-pull power amplifier circuit is the first mode, the third capacitor C411, the fourth capacitor C412 and the second inductor L52 can participate in the push-pull The output impedance of the power amplifier circuit is matched to flexibly adjust the output impedance of the push-pull power amplifier circuit.

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

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

In this embodiment, by coupling the first end of the first primary coil section to the output end of the first power amplifier M1, the second end of the first primary coil section is connected to the first end of the adjustable capacitor Ct, and The first end of the second primary coil section is coupled to the output end 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 capacitor Ct, so as to operate according to the push-pull power amplifier circuit. frequency band, flexibly adjust the capacitance value of the adjustable capacitor Ct, and flexibly perform impedance matching on the push-pull power amplifier circuit.

Optionally, the push-pull power amplifier circuit also 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 section, and the first end of the second matching inductor L82 Connected to the output end of the second power amplifier M2, the second end of the second matching inductor L82 is connected to the first end of the second primary coil section. The first matching inductor L81 and the second matching inductor L82 are used to participate in push-pull power amplification. Impedance matching of the 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 section. The second matching inductor L82 can be realized by a transmission line between the output end of the second power amplifier M2 and the first end of the second primary coil section.

Optionally, the push-pull power amplifier circuit also includes a harmonic suppression capacitor C81. The first terminal of the harmonic suppression capacitor C81 is connected to the output terminal of the first power amplifier M1. The second terminal of the harmonic suppression capacitor C81 is connected to the output terminal of the first power amplifier M1. The output terminals of the two power amplifiers M2 are connected and configured to suppress odd harmonic signals of the push-pull power amplifier circuit.

In one embodiment, as shown in FIG. 5 , the push-pull power amplifier circuit further includes a first switchable harmonic suppression circuit 60 and a second switchable harmonic suppression circuit 70 ; One end is connected to the first input end of the first balun 20, the second end of the first switchable harmonic suppression circuit 60 is connected to ground; the first end of the second switchable harmonic suppression circuit 70 is connected to the first input end of the first balun 20. The second input terminal is connected, and the second terminal of the second switchable harmonic suppression circuit 70 is connected to ground; 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 consistent with each other. The operating frequency band of the power amplifier circuit is negatively correlated.

In a specific embodiment, the first terminal of the first switchable harmonic suppression circuit 60 is connected to the first input terminal of the first balun 20 , and the second terminal of the first switchable harmonic suppression circuit 60 is connected to ground, and is configured In order to suppress the even harmonic signal of the push-pull power amplifier circuit.

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

In a specific embodiment, the first terminal of the second switchable harmonic suppression circuit 70 is connected to the second input terminal of the first balun 20 , the second terminal of the second switchable harmonic suppression circuit 70 is connected to ground, and is configured In order to suppress the even harmonic signal of the push-pull power amplifier circuit.

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

It should be noted that the specific circuit structures and resonant frequency point configurations of the first switchable harmonic suppression circuit 60 and the second switchable harmonic suppression circuit 70 are the same as those of the third switchable harmonic suppression circuit in the above embodiment. The circuit structure and the configuration of the resonant frequency points are similar, for example, C61, C62, L61 and S61 in the first switchable harmonic suppression circuit 60 in Figure 5, and C71, C72 in the second switchable harmonic suppression circuit 70 , L71 and S71, which will not be described again here.

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

In a specific embodiment, when the push-pull power amplifier circuit operates in the high frequency band, the first radio frequency output signal is output through the first output matching circuit 30. When the push-pull power amplifier circuit operates in the medium frequency band, the first radio frequency output signal is output through the second output matching circuit 30. The output matching circuit 40 outputs the second radio frequency output signal to achieve impedance matching of the push-pull power amplifier circuit under different operating frequency bands, thereby optimizing the bandwidth performance of the push-pull power amplifier circuit.

In one embodiment, the coupling degree between the primary winding and the first secondary coil section is less than the coupling degree between the primary winding and the second secondary coil section.

In a specific embodiment, when the coupling method between the primary winding and the first secondary coil section and the coupling method between the primary winding and the second secondary coil section are the same, the coupling degree between the primary winding and the first secondary coil section is, with the primary winding and The coupling of the second secondary coil section is the same. However, in the actual application process, the coupling method between the primary winding and the first secondary coil section is the same as the coupling method between the primary winding and the second secondary coil section, that is, the coupling degree between the primary winding and the first secondary coil section, When the coupling degree between the primary winding and the second secondary coil section is the same, if the radio frequency signals of different frequency bands are converted respectively, the coupling degree between the primary winding and the first secondary coil section will be different from that between the primary winding and the second secondary coil section. The secondary coil segments exhibit different degrees of coupling. For example, by coupling the primary winding to the first secondary coil section, the coupling degree when converting the high-frequency radio frequency signal is greater than that of coupling the primary winding and the second secondary coil section to convert the low-frequency radio frequency signal. The degree of coupling when performing the conversion, which in turn results in an imbalance between the degree of coupling between the primary winding and the first secondary coil section and the degree of coupling between the primary winding and the second secondary coil section. Therefore, in this embodiment, the coupling degree between the primary winding that outputs the first radio frequency output signal and the first secondary coil section is smaller than the coupling degree between the primary winding that outputs the second radio frequency output signal and the second secondary coil section to balance 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 under different radio frequency signals.

In one embodiment, the first balun 20 is applied to a substrate, and the substrate includes a first metal layer and a second metal layer arranged adjacently; the first secondary coil section is arranged on the first metal layer, and the second secondary coil The segment is arranged 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 upper and lower layers of the second secondary coil segment.

In a specific embodiment, since the primary winding is coupled with the first secondary coil section to convert the first radio frequency signal and the high frequency band radio frequency signal, and the primary winding is coupled with the second secondary coil section, to convert the second radio frequency signal and the low frequency band radio frequency signal. Therefore, in this embodiment, by disposing 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 connected to the first secondary coil segment. Same-layer coupling enables the primary winding of the first balun 20 to be coupled to the upper and lower layers of the second secondary coil section. In this embodiment, since the coupling degree of the same-layer coupling is originally smaller than the coupling degree of the upper-lower layer coupling, the primary winding of the first balun 20 and the first secondary coil section will be coupled to the same layer, so that the first balun 20 will be coupled to the first secondary coil section. The primary winding of the Lun 20 is coupled to the upper and lower layers of the second secondary coil section, so that the coupling degree between the primary winding that outputs the first RF output signal and the first secondary coil section is the same as that between the primary winding that outputs the second RF output signal and the second secondary coil section. The coupling degree of the secondary coil section is balanced to ensure the balance of the RF output signal output under different operating frequency bands.

It should be noted that in this embodiment, the primary winding of the first balun 20 is coupled to the upper and lower layers of the first secondary coil section, and the primary winding and the second secondary coil section are coupled to the same layer as an exemplary explanation. Including but not limited to any other implementation 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.

The above-described embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still implement the above-mentioned implementations. The technical solutions described in the examples are modified, or some of the technical features are equivalently replaced; however, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions in the embodiments of the present application. All should be included in the protection scope of this application.

Claims (13)

1. A push-pull power amplifier circuit, which 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 section One end is connected to the first output matching circuit, the second end of the first secondary coil section is connected to ground; the first end of the second secondary coil section is connected to the second output matching circuit, the The second end of the second secondary coil section is grounded;

   When the working mode of the push-pull power amplifier circuit is the first mode, the 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, the first radio frequency output signal is output through the first output matching circuit. The second output matching circuit outputs a second radio frequency output signal.
2. The push-pull power amplifier circuit of claim 1, wherein when the operating 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 operating 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 of claim 1, wherein the first output matching circuit includes a first switch and a first matching network; the first end of the first matching network is connected to the first secondary The first end of the coil section is connected, the second end of the first matching network is connected to ground; the third end of the first matching network is connected to the first end of the first switch; in the push-pull power amplification When the working mode of the circuit is the second mode, the first switch is turned off, 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 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 section, and the second matching network 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 switch; when the working mode of the push-pull power amplifier circuit is the first mode, the The second switching switch is turned off, 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.
4. The push-pull power amplifier circuit of claim 3, wherein the first matching network includes a second electrical The first end of the second capacitor is connected to the first end of the first switch, and the second end of the second capacitor is grounded; the first output matching circuit also includes a fifth capacitor, the One end of the fifth capacitor is connected to the second end of the first switch; the second end of the fifth capacitor is connected to ground;

   The second matching network 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 connected to ground; the second output matching The circuit also includes a sixth capacitor, 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 ground.
5. The push-pull power amplifier circuit of claim 4, wherein the first matching network further includes a first capacitor, a first end of the first capacitor is connected to a first end of the first secondary coil section , the second end of the first capacitor is connected to the first end of the first switch and the first end of the first two capacitors; the second matching network also includes a third capacitor, the third The first end of the capacitor is connected to the first end of the second secondary coil section, and the second end of the third capacitor is connected to the first end of the second switch and the first end of the fourth capacitor. connect.
6. The push-pull power amplifier circuit of claim 4, wherein the push-pull power amplifier circuit further includes an adjustment matching circuit; the adjustment matching circuit is disposed 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 operating mode of the push-pull power amplifier circuit.
7. The push-pull power amplifier circuit of claim 1, wherein the first output matching circuit includes a first switch and a first matching network; the first end of the first switch and the first secondary coil The first end of the segment is connected, and the second end of the first switch is connected to the first matching network;

   The second output matching circuit includes a second switch and a second matching network; the first end of the second switch is connected to the first end of the second secondary coil section, and the second end of the second switch is The second end 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 When , the first switch is turned off and the second switch is turned on.
8. The push-pull power amplifier circuit of claim 7, wherein 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 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 connected to ground. The first end of the first capacitor is connected to the ground. The second end of the inductor is the output node of the first matching network;

   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, and the second end of the third capacitor with the first terminal of the fourth capacitor and the The first end of the second inductor is connected to the ground, the second end of the fourth capacitor is connected to ground, and the second end of the second inductor is the output node of the second matching network.
9. The push-pull power amplifier circuit of claim 7, wherein 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 section is coupled to the output end of the first power amplifier, and the second end of the first primary coil section is connected to the first end of the adjustable capacitor;

   The first end of the second primary coil section is coupled to the output end of the second power amplifier, and the second end of the second primary coil section is connected to the second end of the adjustable capacitor.
10. The push-pull power amplifier circuit of claim 1, wherein the push-pull power amplifier circuit further includes a first switchable harmonic suppression circuit and a second switchable harmonic suppression circuit;

    The first end of the first switchable harmonic suppression circuit is connected to the first input end of the first balun, and the second end of the first switchable harmonic suppression circuit is connected to ground;

    The first end of the second switchable harmonic suppression circuit is connected to the second input end of the first balun, and the second end of the second switchable harmonic suppression circuit is connected to ground;

    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.
11. The push-pull power amplifier circuit of claim 1, wherein when the push-pull power amplifier circuit operates in the first frequency band, the first radio frequency output signal is output through the first output matching circuit; When the power amplifier circuit operates in the second frequency band, the second output matching circuit outputs a second radio frequency output signal, and the first frequency band is greater than the second frequency band.
12. The push-pull power amplifier circuit of claim 11 , wherein the coupling degree between the primary winding and the first secondary coil section is smaller than the coupling degree between the primary winding and the second secondary coil section.
13. The push-pull power amplifier circuit of claim 12, wherein the first balun is applied on a substrate, the substrate includes a first metal layer and a second metal layer arranged adjacently; the first secondary The 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 and the first secondary coil segment are coupled in the same layer, The primary winding of the first balun is coupled to the upper and lower layers of the second secondary coil section.