CN115913152A - Push-pull power amplifying circuit and radio frequency front end module - Google Patents

Abstract

The invention discloses a push-pull power amplifier circuit and a radio frequency front-end module, comprising a first push-pull power amplifier, a second push-pull power amplifier and a tuning circuit; the first push-pull power amplifier includes a first balun, the second push-pull power amplifier The pull power amplifier includes a second balun; the first output terminal of the first balun outputs a radio frequency output signal, the second output terminal is connected to the first output terminal of the second balun, and the second output terminal of the second balun is connected to the ground One end of the tuning circuit is connected to the second output end of the first balun and the second balun, and the other end is connected to the ground end; the tuning circuit is configured to correct the common mode in the radio frequency output signal The signal is tuned, so that the common mode signal in the radio frequency output signal output by the push-pull power amplifier circuit is effectively suppressed, and the total loss of the push-pull power amplifier circuit is greatly reduced.

Description

Push-pull power amplifier circuit and RF front-end module

technical field

The invention relates to the field of radio frequency technology, in particular to a push-pull power amplifier circuit and a radio frequency front-end module.

Background technique

Mobile communication technology has evolved to the fifth generation, and 5G NR (5th-Generation New Radio), as a global 5G standard based on a new air interface design based on Orthogonal Frequency Division Multiplexing (OFDM), is also very important for the next generation The basis of cellular mobile technology. As the core radio frequency unit in the communication system, the push-pull power amplifier circuit has a great influence on the performance characteristics of the whole system, especially its loss characteristics, which seriously affect the total power consumption of the entire communication system. Therefore, how to avoid excessive loss of the push-pull power amplifier circuit has become an urgent problem to be solved at present.

Contents of the invention

Embodiments of the present invention provide a push-pull power amplifier circuit and a radio frequency front-end module to solve the problem of excessive loss of the push-pull power amplifier circuit.

A push-pull power amplifier circuit, including a first push-pull power amplifier, a second push-pull power amplifier and a tuning circuit; the first push-pull power amplifier includes a first balun, and the second push-pull power amplifier includes a first push-pull power amplifier Two baluns; the first output end of the first balun outputs a radio frequency output signal, the second output end is connected to the first output end of the second balun, and the second output end of the second balun is connected to the second output end of the second balun. connected to the ground terminal; one terminal of the tuning circuit is connected to the second output terminal of the first balun and the first output terminal of the second balun, and the other terminal is connected to the ground terminal; the tuning circuit is configured to The common mode signal in the radio frequency output signal is tuned.

Further, the tuning circuit includes a first inductor.

Further, the tuning circuit includes a first resistor.

Further, the tuning circuit includes a first resistor and a first inductor connected in series, or includes a first resistor and a first inductor connected in parallel.

Further, the first push-pull power amplifier also includes a first differential amplifier transistor and a second differential amplifier transistor, and the second push-pull power amplifier includes a third differential amplifier transistor and a fourth differential amplifier transistor; A differential amplifier transistor is configured to receive a first radio frequency signal and output a first radio frequency amplified signal to the first input terminal of the first balun; the second differential amplifier transistor is configured to receive a second radio frequency signal and output a first radio frequency signal The second radio frequency amplified signal is sent to the second input terminal of the first balun; the third differential amplifier transistor is configured to receive a third radio frequency signal, and output the third radio frequency amplified signal to the first input of the second balun terminal; the first terminal of the fourth differential amplifier transistor is configured to receive the fourth radio frequency signal; output the fourth radio frequency amplified signal to the second input terminal of the second balun; the first differential amplifier transistor is set away from the One side of the second push-pull power amplifier, and the fourth differential amplifier transistor is disposed on a side away from the first push-pull power amplifier.

Further, the phase of the first radio frequency signal is the same as that of the third radio frequency signal; the phase of the second radio frequency signal is the same as that of the fourth radio frequency signal.

Further, the first differential amplifier transistor is an HBT tube, including a base, a collector and an emitter, the base of the first differential amplifier transistor receives the input first radio frequency signal, and the first differential amplifier transistor The collector is coupled to the first input terminal of the first balun, and the emitter of the first differential amplifier transistor is grounded; the second differential amplifier transistor is an HBT tube, including a base, a collector, and an emitter, so The base of the second differential amplifier transistor receives the input second radio frequency signal, the collector of the second differential amplifier transistor is coupled to the second input terminal of the first balun, and the emitter of the second differential amplifier transistor grounded; the base of the third differential amplifier transistor receives the input third radio frequency signal, the collector of the third differential amplifier transistor is coupled to the first input terminal of the second balun, and the third differential The emitter of the amplifying transistor is grounded; the base of the fourth differential amplifying transistor receives the input fourth radio frequency signal, and the collector of the fourth differential amplifying transistor is coupled to the second input terminal of the second balun, so The emitter of the fourth differential amplifier transistor is grounded.

Further, the first balun includes a primary winding and a secondary winding, the primary winding includes a first primary coil and a second primary coil; the secondary winding includes a first secondary coil and a second secondary coil; The first primary coil and the first secondary coil are coupled to form a first coupling coil, and the second primary coil and the second secondary coil are coupled to form a second coupling coil; the first coupling coil and the The second coupling coil is set far away.

A radio frequency front-end module, including a substrate, a push-pull power amplifier chip arranged on the substrate, a first balun and a second balun arranged on the substrate, and a tuning circuit arranged on the substrate The push-pull power amplifier chip includes a first differential amplifier transistor, a second differential amplifier transistor, a third differential amplifier transistor and a fourth differential amplifier transistor; the first differential amplifier transistor is configured to receive a first radio frequency signal, and The first differential amplifier transistor is connected to the first pad of the push-pull power amplifier chip, and the first pad is wire-bonded to the first input terminal of the first balun; the second differential The amplifying transistor is configured to receive a second radio frequency signal, the second differential amplifying transistor is connected to a second pad of the push-pull power amplifying chip, and the second pad is wire-bonded to the first bar The second input terminal of Lun; the third differential amplifier transistor is configured to receive a third radio frequency signal, the third differential amplifier transistor is connected to the third pad of the push-pull power amplifier chip, and the third solder pad The pad wire is bonded to the first input terminal of the second balun; the fourth differential amplifier transistor is configured to receive a fourth radio frequency signal, and the fourth differential amplifier transistor is connected to the push-pull power amplifier chip The fourth pad is connected, and the fourth pad is wire-bonded to the second input end of the second balun; the first output end of the first balun outputs a radio frequency output signal, and the second output terminal is connected to the first output terminal of the second balun, and the second output terminal of the second balun is connected to the ground terminal; one terminal of the tuning circuit is connected to the second output terminal of the first balun and The first output end of the second balun is connected, and the other end is connected to the ground end; the tuning circuit is configured to tune the common mode signal in the radio frequency output signal.

Further, the tuning circuit includes a planar spiral inductor, or, the tuning circuit includes an SMD inductor, or, the tuning circuit includes an SMD resistor.

The above-mentioned push-pull power amplifier circuit includes a first push-pull power amplifier, a second push-pull power amplifier and a tuning circuit; the first push-pull power amplifier includes a first balun, and the second push-pull power amplifier includes a first push-pull power amplifier Two baluns; the first output end of the first balun outputs a radio frequency output signal, the second output end is connected to the first output end of the second balun, and the second output end of the second balun is connected to the second output end of the second balun. connected to the ground terminal; one end of the tuning circuit is connected to the second output terminal of the first balun and the second balun, and the other end is connected to the ground terminal; the tuning circuit is configured to output the radio frequency The common mode signal in the signal is tuned; in this embodiment, the second output terminal of the first balun is connected to the first output terminal of the second balun, and the second output terminal of the first balun is connected to the first output terminal of the second balun. A tuning circuit to the ground is connected between the first output terminals of the second balun mentioned above, and the tuning circuit is configured to tune the common mode signal in the RF output signal, that is, to move the resonance peak point generated in the frequency band to the outside of the frequency band Offset, (preferably, shift the resonant drum peak point generated in the frequency band to the low frequency band outside the frequency band), or suppress the harmonic drum peak point generated in the frequency band, so as to realize the output of the push-pull power amplifier circuit The common mode signal in the RF output signal is effectively suppressed, thereby greatly reducing the total loss of the push-pull power amplifier circuit.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments of the present invention. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention , for those skilled in the art, other drawings can also be obtained according to these drawings without paying creative labor.

Fig. 1 is a schematic circuit diagram of a push-pull power amplifier circuit in an embodiment of the present invention;

Fig. 2 is another schematic circuit diagram of a push-pull power amplifier circuit in an embodiment of the present invention;

Fig. 3 is another schematic circuit diagram of a push-pull power amplifier circuit in an embodiment of the present invention;

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

5 is another schematic circuit diagram of a push-pull power amplifier circuit in an embodiment of the present invention;

6 is another schematic circuit diagram of a push-pull power amplifier circuit in an embodiment of the present invention;

7 is a schematic circuit diagram of a radio frequency front-end module in an embodiment of the present invention;

FIG. 8 is another schematic circuit diagram of a radio frequency front-end module in an embodiment of the present invention;

FIG. 9 is another schematic circuit diagram of the radio frequency front-end module in an embodiment of the present invention.

In the figure: 10, the first push-pull power amplifier; 11, the first balun; 20, the thermal push-pull power amplifier; 21, the second balun; M1, the second differential amplifier transistor; M2, the second differential amplifier transistor ; M3, third differential amplifier transistor; M4, fourth differential amplifier transistor; 100, substrate; 200, push-pull power amplifier chip; 30, tuning circuit; C1, first capacitor; C2, second capacitor; L1, first Inductance; R1, the first resistor.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

It should be understood that the invention can 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 invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity, and like reference numerals designate like elements throughout.

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, on, or "coupled to" the other element or layer. Other elements or layers may be adjacent to, connected to or coupled to, 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 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.

Spatial terms such as "below", "under", "beneath", "below", "above", "above", etc., may be used herein for convenience of description The relationship of one element or feature to other elements or features shown in the figures is thus described. 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 "below" or "beneath" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary terms "below" and "beneath" can encompass both an orientation of above and below. 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 invention. 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 should also be understood that the terms "consists of" and/or "comprising", when used in this specification, identify the presence of features, integers, steps, operations, elements and/or parts, but do not exclude one or more other features, Presence or addition of integers, steps, operations, elements, parts and/or groups. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

In order to thoroughly understand the present invention, detailed structures and steps will be provided in the following descriptions in order to illustrate the technical solutions proposed by the present invention. Preferred embodiments of the present invention are described in detail below, however, the present invention may have other embodiments besides these detailed descriptions.

This embodiment provides a push-pull power amplifier circuit, as shown in FIG. 1 , including a first push-pull power amplifier 10 , a second push-pull power amplifier 20 and a tuning circuit 30 . The first push-pull power amplifier 10 includes a first balun 11 , and the second push-pull power amplifier 20 includes a second balun 21 . The first output terminal of the first balun 11 outputs a radio frequency output signal, the second output terminal is connected to the first output terminal of the second balun 21, and the second output terminal of the second balun 21 is connected to ground end connection.

In a specific embodiment, the push-pull power amplifying circuit further includes a pre-stage conversion circuit (not shown in the figure), and the input end of the pre-stage conversion circuit receives the radio frequency input signal as a signal input end of the push-pull power amplifying system, and is configured To convert the RF input signal, output the first RF signal and the second RF signal to the first push-pull power amplifier 10 , and output the third RF signal and the fourth RF signal to the second push-pull power amplifier 20 . Optionally, the pre-stage conversion circuit may be a circuit composed of two conversion baluns, or a circuit composed of three conversion baluns, or a circuit of any other topology. In this embodiment, the specific circuit structure of the pre-stage conversion circuit is not limited.

Wherein, the first push-pull power amplifier 20 is used for amplifying the first radio frequency signal and the second radio frequency signal. The second push-pull power amplifier 30 is used for amplifying the third radio frequency signal and the fourth radio frequency signal. It can be understood that the push-pull power amplifier circuit of the present application includes a first push-pull power amplifier 20 and a second push-pull power amplifier 30. Compared with a circuit that only includes a single push-pull power amplifier, the push-pull power amplifier circuit of the present application With greater output power.

The first push-pull power amplifier 10 includes a first balun 11 , and the second push-pull power amplifier 20 includes a second balun 21 . Wherein, the first balun 11 is configured to convert and synthesize the first radio frequency signal and the second radio frequency signal amplified by the first push-pull power amplifier 10 . The second balun 21 is configured to convert and synthesize the third radio frequency signal and the fourth radio frequency signal amplified by the second push-pull power amplifier 20 .

The first output terminal of the first balun 11 outputs a radio frequency output signal, the second output terminal is connected to the first output terminal of the second balun 21, and the second output terminal of the second balun 21 is connected to ground end connection. One end of the tuning circuit is connected to the second output end of the first balun 11 and the second balun, and the other end is connected to the ground. The tuning circuit is configured to tune a common mode signal in the radio frequency output signal.

In a specific embodiment, since the first balun 11 and/or the second balun 21 will inevitably have some parasitic capacitance, there will be some common mode interference in the radio frequency output signal output by the push-pull power amplifier circuit Signal, so that the resonant peak point will be generated in the frequency band, which will bring excessive loss to the push-pull power amplifier circuit. In view of this, in this embodiment, the second output end of the first balun 11 is connected to the first output end of the second balun 21, and the second output end of the first balun is connected to the second output end of the second balun. A tuning circuit 30 connected to the ground is connected between the first output terminals of the balun 21, and the tuning circuit 30 is configured to tune the common mode signal in the radio frequency output signal, that is, to move the resonant peak point generated in the frequency band to the outside of the frequency band Offset, (preferably, shift the resonant drum peak point generated in the frequency band to the low frequency band outside the frequency band), or suppress the harmonic drum peak point generated in the frequency band, so as to realize the output of the push-pull power amplifier circuit The common mode signal in the RF output signal is effectively suppressed, thereby greatly reducing the total loss of the push-pull power amplifier circuit.

In a specific embodiment, as shown in FIG. 2 , the tuning circuit 30 includes a first inductor L1. Specifically, one end of the first inductor L1 is connected between the second output end of the first balun 11 and the first output end of the second balun 21 , and the other end is connected to the ground end. The first inductance L1 and the parasitic capacitance generated by the first balun 11 and/or the second balun 21 form an LC resonant circuit, thereby suppressing the harmonic peaks generated in the frequency band and achieving the desired effect on the push-pull power amplifier circuit The purpose of suppressing the common mode signal in the output radio frequency output signal, thereby greatly reducing the total loss of the push-pull power amplifier circuit.

In a specific embodiment, in order to avoid effectively suppressing the common-mode signal in the radio frequency output signal output by the push-pull power amplifier circuit, while introducing other unnecessary losses due to the inductor itself, the inductance value of the first inductor L1 It is 1μH-3μH. Preferably, the inductance value of the first inductor L1 is 2 μH.

In a specific embodiment, as shown in FIG. 3 , the tuning circuit 30 includes a first resistor R1. Specifically, one end of the first resistor R1 is connected between the second output end of the first balun 11 and the first output end of the second balun 21 , and the other end is connected to the ground end. The first resistor R1 and the parasitic capacitance produced by the first balun 11 and/or the second balun 21 form an RC circuit, thereby shifting the resonance drum point generated in the frequency band to the outside of the frequency band, (preferably, the frequency band The generated resonant drum peak point shifts to the low frequency band outside the frequency band) to achieve the purpose of suppressing the common mode signal in the RF output signal output by the push-pull power amplifier circuit, thereby greatly reducing the total loss of the push-pull power amplifier circuit .

In a specific embodiment, in order to avoid effectively suppressing the common-mode signal in the radio frequency output signal output by the push-pull power amplifier circuit, while introducing other unnecessary losses due to the resistance itself, the resistance value of the first resistance R1 Preferably it is 10Ω.

In a specific embodiment, as shown in FIG. 4 and FIG. 5 , the tuning circuit includes a first resistor R1 and a first inductor L1 connected in series, or includes a first resistor R1 and a first inductor L1 connected in parallel. Specifically, the first resistor R1, the first inductance L1 and the parasitic capacitance generated by the first balun 11 and/or the second balun 21 form a tuning circuit, thereby shifting the peak point of the resonant drum generated in the frequency band to the outside of the frequency band , (preferably, the resonant drum peak point that produces in the frequency band is shifted to the low frequency band outside the frequency band), reaches the purpose that the common mode signal in the radio frequency output signal output by the push-pull power amplifier circuit is suppressed, thereby greatly reducing The total loss of the push-pull power amplifier circuit.

6 below, the first push-pull power amplifier 10 also includes a first differential amplifier transistor M1 and a second differential amplifier transistor M2, and the second push-pull power amplifier 20 includes a third differential amplifier transistor M3 and The fourth differential amplifier transistor M4.

The first differential amplifier transistor M1 is configured to receive a first radio frequency signal, and output a first radio frequency amplified signal to the first input terminal of the first balun 11; the second differential amplifier transistor M2 is configured to receive a first radio frequency signal Two radio frequency signals, outputting a second radio frequency amplified signal to the second input end of the first balun 11 . The third differential amplifier transistor M3 is configured to receive a third radio frequency signal, and output the third radio frequency amplified signal to the first input end of the second balun 21; the first end of the fourth differential amplifier transistor M4 is configured to receiving the fourth radio frequency signal; outputting the fourth radio frequency amplified signal to the second input terminal of the second balun 21 .

Wherein, the first differential amplifier transistor M1 , the second differential amplifier transistor M2 , the third differential amplifier transistor M3 and the fourth differential amplifier transistor M4 may be HBT transistors or field effect transistors (FETs). Optionally, the first differential amplifier transistor M1 includes at least one HBT transistor (eg, HBT transistor) or at least one field effect transistor. Exemplarily, the first differential amplifier transistor M1 may be formed by connecting multiple HBT transistors in parallel. The second differential amplifier transistor M2 includes at least one HBT transistor (eg, HBT transistor) or at least one field effect transistor. Exemplarily, the second differential amplifier transistor M2 may be formed by a plurality of HBT transistors connected in parallel. The third differential amplifier transistor M3 includes at least one HBT transistor (eg, HBT transistor) or at least one field effect transistor. Exemplarily, the third differential amplifier transistor M3 may be formed by a plurality of HBT transistors connected in parallel. The fourth differential amplifier transistor M4 includes at least one HBT transistor (eg, HBT transistor) or at least one field effect transistor. Exemplarily, the fourth differential amplifier transistor M4 may be a plurality of HBT transistors connected in parallel.

It can be understood that the first differential amplifier transistor M1 and the second differential amplifier transistor M2 can be any amplifier stage in the first push-pull power amplifier, for example, the amplifier stage can be a driver stage, an intermediate stage or an output stage any magnification level. The third differential amplifier transistor M3 and the fourth differential amplifier transistor M4 can be any amplification stage in the second push-pull power amplifier. class

The first differential amplifier transistor M1 is arranged on a side away from the second push-pull power amplifier 20 , and the fourth differential amplifier transistor M4 is arranged on a side away from the first push-pull power amplifier 10 .

Specifically, the phase of the first radio frequency signal is the same as that of the third radio frequency signal; the phase of the second radio frequency signal is the same as that of the fourth radio frequency signal. The first radio frequency signal and the second radio frequency signal are a pair of balanced differential signals. The third radio frequency signal and the fourth radio frequency signal are a pair of balanced differential signals.

In a specific embodiment, if the phase of the first radio frequency signal received by the first differential amplifier transistor M1 is 0 degrees, and the phase of the second radio frequency signal received by the second differential amplifier transistor M2 is 180 degrees, then the third differential amplifier transistor The phase of the third radio frequency signal received by M3 is 180 degrees, and the phase of the fourth radio frequency signal received by the fourth differential amplifier transistor M4 is 0 degrees. It should be noted that it is only necessary to ensure that the phase of the first radio frequency signal received by the first differential amplifier transistor M1 is the same as that of the third radio frequency signal received by the third differential amplifier transistor M3; the phase of the second radio frequency signal received by the second differential amplifier transistor M2 The phase of the signal may be the same as the phase of the fourth radio frequency signal received by the fourth differential amplifier transistor M4.

In this embodiment, the phase of the first radio frequency signal received by the first differential amplifier transistor M1 is the same as the phase of the third radio frequency signal received by the third differential amplifier transistor M3; the second radio frequency signal received by the second differential amplifier transistor M2 The phase of the phase and the fourth radio frequency signal received by the fourth differential amplifier transistor M4 are the same; that is, the first push-pull power amplifier 10 and the second push-pull power amplifier 20 are the same push-pull power amplifier, therefore, adopt the same two The push-pull power amplifier can not only improve the overall performance of the push-pull power amplifier circuit, but also improve the flexibility and reusability of the push-pull power amplifier circuit in practical applications.

In a specific embodiment, the first differential amplifier transistor M1 is an HBT tube, including a base, a collector, and an emitter, and the base of the first differential amplifier transistor M1 receives an input first radio frequency signal, and the The collector of the first differential amplifier transistor M1 is coupled to the first input terminal of the first balun 11, and the emitter of the first differential amplifier transistor M1 is grounded; the second differential amplifier transistor M2 is an HBT tube, comprising Base, collector and emitter, the base of the second differential amplifier transistor M2 receives the input second radio frequency signal, the collector of the second differential amplifier transistor M2 is coupled to the first balun 11 Two input terminals, the emitter of the second differential amplifier transistor M2 is grounded; the base of the third differential amplifier transistor M3 receives the input third radio frequency signal, and the collector of the third differential amplifier transistor is coupled to the The first input end of the second balun 11, the emitter of the third differential amplifier transistor M3 is grounded; the base of the fourth differential amplifier transistor M4 receives the input fourth radio frequency signal, and the fourth differential amplifier transistor M4 The collector of M4 is coupled to the second input terminal of the second balun 11 , and the emitter of the fourth differential amplifier transistor M4 is grounded.

In a specific embodiment, the first balun 30 includes a primary winding and a secondary winding, the primary winding includes a first primary coil and a second primary coil; the secondary winding includes a first secondary coil and a second A secondary coil; the first primary coil is coupled with the first secondary coil to form a first coupled coil, and the second primary coil is coupled with the second secondary coil to form a second coupled coil; the first A coupled coil and the second coupled coil are located remotely. Wherein, the first coupling coil and the second coupling coil may be disposed on the same metal layer, or may be disposed on adjacent different metal layers.

Specifically, a part of the primary winding forms a first primary coil, and another part forms a second primary coil. Starting from the first end of the primary winding, the wiring direction of the first primary coil is the first direction; starting from the second end of the primary winding, the wiring direction of the second primary coil is the second direction. One part of the secondary winding forms the first secondary coil and the other part forms the second secondary coil. Starting from the first end of the secondary winding, the wiring direction of the first secondary coil is the first direction; starting from the second end of the secondary winding, the wiring of the second secondary coil is The direction is the second direction. The first direction is opposite to the second direction, and the first coupling coil and the second coupling coil are arranged away from each other.

It can be understood that the wiring direction is used to describe the direction of the coil direction presented by the external structure of the coil, and is not limited to the winding direction of the coil during design or manufacture. As an example, starting from the first end of the primary winding, the coil direction of the first primary coil is clockwise; starting from the second end of the primary winding, the wiring direction of the second primary coil is counterclockwise.

In a specific embodiment, since the first direction is opposite to the second direction, the current on the side adjacent to the second coupling coil in the first coupling coil and the current on the side adjacent to the first coupling coil in the second coupling coil Therefore, by setting the first coupling coil and the second coupling coil away from each other, the mutual cancellation between the currents can be avoided to affect the coupling degree between the primary winding and the secondary winding, thereby improving the primary winding and the secondary winding the degree of coupling between them.

This embodiment provides a radio frequency front-end module, as shown in FIG. The second balun 21 and the tuning circuit 30 arranged on the substrate 100 .

The push-pull power amplifier chip 200 includes a first differential amplifier transistor M1, a second differential amplifier transistor M2, a third differential amplifier transistor M3 and a fourth differential amplifier transistor M4; the first differential amplifier transistor M1 is configured to receive the first differential amplifier transistor M4 A radio frequency signal, the first differential amplifier transistor M1 is connected to the first pad a of the push-pull power amplifier chip 200, and the first pad a is wire-bonded to the first balun 11 first input. The second differential amplifier transistor M2 is configured to receive a second radio frequency signal, the second differential amplifier transistor M2 is connected to the second pad b of the push-pull power amplifier chip 200, and the second pad b leads Bonded to the second input end of the first balun 11 . The third differential amplifier transistor M3 is configured to receive a third radio frequency signal, the third differential amplifier transistor M3 is connected to the third pad c of the push-pull power amplifier chip 200, and the third pad c leads Bonded to the first input terminal 21 of the second balun; the fourth differential amplifier transistor M4 is configured to receive a fourth radio frequency signal, and the fourth differential amplifier transistor M4 is connected to the push-pull power amplifier The fourth pad d of the chip 200 is connected, and the fourth pad d is wire-bonded to the second input end of the second balun 21 .

In a specific embodiment, in order to realize the electrical connection between the first differential amplifying transistor M1 and the second differential amplifying transistor M2 disposed on the push-pull power amplifier chip 200 and the first balun 11 disposed on the substrate, and realize setting The electrical connection between the third differential amplifier transistor M3 and the fourth differential amplifier transistor M4 on the push-pull power amplifier chip 200 and the second balun 21 provided on the substrate can be connected by wire bonding. In the present application, the first pad a, the second pad b, the third pad c, and the fourth pad d are provided on the push-pull power amplifier chip 200, and the output of the first differential amplifying transistor M1 connected to the first pad a of the push-pull power amplifier chip 200, and the first pad a is bonded to the first input end of the first balun 11 by wire bonding, wherein the first pad a Disk a may be bonded to the first input end of the first balun 11 via one or more wires. And the output terminal of the second differential amplifier transistor M2 is connected to the second pad b of the push-pull power amplifier chip 200, and the second pad b is bonded to the first balun 11 by wire bonding. The second input terminal, wherein, the second pad b can be bonded to the first input terminal of the first balun 11 through one or more wires; thereby realizing the setting on the push-pull power amplifier chip The electrical connection between the first differential amplifier transistor M1 and the second differential amplifier transistor M2 and the first balun 11 provided on the substrate. Similarly, the output terminal of the third differential amplifier transistor M3 is connected to the third pad c of the push-pull power amplifier chip 200, and the third pad c is bonded to the first coil section by wire bonding wherein, the third pad c can be bonded to the first input end of the second balun 21 through one or more wires. And connecting the output end of the fourth differential amplifier transistor M4 to the fourth pad d of the push-pull power amplifier chip 200, the fourth pad d is bonded to the second coil section of the second coil section by wire bonding. terminal, wherein, the fourth pad d can be bonded to the second input terminal of the second balun 21 through one or more wires; Electrical connection between the amplification transistor M3 and the fourth differential amplification transistor M4 and the second balun 21 disposed on the substrate.

The first output terminal of the first balun 11 outputs a radio frequency output signal, the second output terminal is connected to the first output terminal of the second balun, and the second output terminal of the second balun 21 is connected to the ground terminal connect. One end of the tuning circuit 30 is connected to the second output end of the first balun 11 and the second balun 21 , and the other end is connected to the ground.

In a specific embodiment, since the first balun 11 and/or the second balun 21 will inevitably have some parasitic capacitance, there will be some common mode interference in the radio frequency output signal output by the push-pull power amplifier circuit Signal, so that the resonant peak point will be generated in the frequency band, which will bring excessive loss to the push-pull power amplifier circuit. In view of this, in this embodiment, the second output end of the first balun 11 is connected to the first output end of the second balun 21, and the second output end of the first balun is connected to the second output end of the second balun. A tuning circuit 30 connected to the ground is connected between the first output terminals of the balun 21, and the tuning circuit 30 is configured to tune the common mode signal in the radio frequency output signal, that is, to move the resonant peak point generated in the frequency band to the outside of the frequency band Offset, (preferably, shift the resonant drum peak point generated in the frequency band to the low frequency band outside the frequency band), or suppress the harmonic drum peak point generated in the frequency band, so as to realize the output of the push-pull power amplifier circuit The common mode signal in the RF output signal is effectively suppressed, thereby greatly reducing the total loss of the push-pull power amplifier circuit.

In a specific embodiment, as shown in FIG. 8 , the tuning circuit 30 includes a planar spiral inductor, or, the tuning circuit includes an SMD inductor. It can be understood that since the tuning circuit 30 is disposed on the substrate, the inductor in the tuning circuit 30 can preferably be realized in the form of a planar spiral inductor or an SMD inductor. The planar spiral inductance/SMD inductance and the parasitic capacitance generated by the first balun 11 and/or the second balun 21 form an LC resonant circuit, thereby suppressing the harmonic peak point generated in the frequency band and achieving push-pull power amplification The purpose of suppressing the common mode signal in the radio frequency output signal output by the circuit, thereby greatly reducing the total loss of the push-pull power amplifier circuit.

In a specific embodiment, in order to avoid effectively suppressing the common-mode signal in the radio frequency output signal output by the push-pull power amplifier circuit, while introducing other unnecessary losses due to the inductor itself, the planar spiral inductor/SMD inductor The inductance value is 1μH-3μH. Preferably, the inductance of the planar spiral inductor/SMD inductor is 2 μH.

In a specific embodiment, as shown in FIG. 9 , the tuning circuit 30 includes SMD resistors. It can be understood that since the tuning circuit 30 is arranged on the substrate, the resistors in the tuning circuit 30 can preferably be implemented in the form of SMD resistors. The SMD resistance and the parasitic capacitance produced by the first balun 11 and/or the second balun 21 form an RC circuit, thereby shifting the resonance drum point generated in the frequency band to the outside of the frequency band, (preferably, the generated in the frequency band The resonant drum peak point is shifted to the low frequency band outside the frequency band) to achieve the purpose of suppressing the common mode signal in the RF output signal output by the push-pull power amplifier circuit, thereby greatly reducing the total loss of the push-pull power amplifier circuit.

In a specific embodiment, in order to avoid effectively suppressing the common-mode signal in the RF output signal output by the push-pull power amplifier circuit, while introducing other unnecessary losses due to the resistance itself, the resistance value of the SMD resistance is preferably 10Ω.

In one embodiment, the above-mentioned push-pull power amplifier chip may be a chip manufactured by using a process such as GaAs or GaN.

It can be understood that, among the connection methods using wire bonding in the embodiment of the present invention, one or more wire bonding methods can be used for connection, and details are not repeated here.

The above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still carry out the foregoing embodiments Modifications to the technical solutions recorded in the examples, or equivalent replacement of some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should be included in within the protection scope of the present invention.

Claims (10)

1. A push-pull power amplifier circuit, characterized in that, comprises a first push-pull power amplifier, a second push-pull power amplifier and a tuning circuit; The first push-pull power amplifier includes a first balun, and the second push-pull power amplifier includes a second balun; The first output terminal of the first balun outputs a radio frequency output signal, the second output terminal is connected to the first output terminal of the second balun, and the second output terminal of the second balun is connected to the ground terminal; One end of the tuning circuit is connected to the second output end of the first balun and the first output end of the second balun, and the other end is connected to the ground end, and the tuning circuit is configured to control the radio frequency The common-mode signal in the output signal is tuned. 2. The push-pull power amplifier circuit according to claim 1, wherein the tuning circuit comprises a first inductor. 3. The push-pull power amplifier circuit according to claim 1, wherein the tuning circuit comprises a first resistor. 4. The push-pull power amplifier circuit according to claim 1, wherein the tuning circuit comprises a first resistor and a first inductor connected in series, or comprises a first resistor and a first inductor connected in parallel. 5. The push-pull power amplifier circuit according to claim 1, wherein the first push-pull power amplifier also includes a first differential amplifier transistor and a second differential amplifier transistor, and the second push-pull power amplifier includes a third differential amplifier transistor and a fourth differential amplifier transistor; The first differential amplifier transistor is configured to receive a first radio frequency signal, and output a first radio frequency amplified signal to a first input terminal of the first balun; The second differential amplifier transistor is configured to receive a second radio frequency signal, and output a second radio frequency amplified signal to the second input terminal of the first balun; The third differential amplifier transistor is configured to receive a third radio frequency signal, and output a third radio frequency amplified signal to the first input terminal of the second balun; The first terminal of the fourth differential amplifier transistor is configured to receive a fourth radio frequency signal; output the fourth radio frequency amplified signal to the second input terminal of the second balun; The first differential amplifier transistor is arranged on a side away from the second push-pull power amplifier, and the fourth differential amplifier transistor is arranged on a side away from the first push-pull power amplifier. 6. The push-pull power amplifying circuit according to claim 5, wherein the phase of the first radio frequency signal is the same as the phase of the third radio frequency signal; the phase of the second radio frequency signal is the same as that of the first radio frequency signal The phases of the four radio frequency signals are the same. 7. The push-pull power amplifier circuit according to claim 5, wherein the first differential amplifier transistor is an HBT tube, comprising a base, a collector and an emitter, and the base of the first differential amplifier transistor receiving the input first radio frequency signal, the collector of the first differential amplifier transistor is coupled to the first input terminal of the first balun, and the emitter of the first differential amplifier transistor is grounded; the second differential amplifier The transistor is an HBT tube, including a base, a collector and an emitter, the base of the second differential amplifier transistor receives the input second radio frequency signal, and the collector of the second differential amplifier transistor is coupled to the first bar The second input end of the RUN, the emitter of the second differential amplifier transistor is grounded; the base of the third differential amplifier transistor receives the input third radio frequency signal, and the collector of the third differential amplifier transistor is coupled to the The first input terminal of the second balun, the emitter of the third differential amplifier transistor is grounded; the base of the fourth differential amplifier transistor receives the input fourth radio frequency signal, and the set of the fourth differential amplifier transistor The electrode is coupled to the second input terminal of the second balun, and the emitter of the fourth differential amplifier transistor is grounded. 8. The push-pull power amplifying circuit according to claim 7, wherein the first balun comprises a primary winding and a secondary winding, and the primary winding comprises a first primary coil and a second primary coil; The secondary winding includes a first secondary coil and a second secondary coil; the first primary coil and the first secondary coil are coupled to form a first coupled coil, and the second primary coil and the second secondary The coils are coupled to form a second coupled coil; the first coupled coil and the second coupled coil are located remotely. 9. A radio frequency front-end module, characterized in that it includes a substrate, a push-pull power amplifier chip arranged on the substrate, a first balun and a second balun arranged on the substrate, and a balun arranged on the substrate The tuning circuit on the substrate; The push-pull power amplifier chip includes a first differential amplifier transistor, a second differential amplifier transistor, a third differential amplifier transistor and a fourth differential amplifier transistor; The first differential amplifier transistor is configured to receive a first radio frequency signal, the first differential amplifier transistor is connected to a first pad of the push-pull power amplifier chip, and the first pad is wire-bonded to the a first input terminal of the first balun; The second differential amplifier transistor is configured to receive a second radio frequency signal, the second differential amplifier transistor is connected to the second pad of the push-pull power amplifier chip, and the second pad is wire-bonded to the a second input terminal of the first balun; The third differential amplifier transistor is configured to receive a third radio frequency signal, the third differential amplifier transistor is connected to a third pad of the push-pull power amplifier chip, and the third pad is wire-bonded to the a first input terminal of the second balun; The fourth differential amplifier transistor is configured to receive a fourth radio frequency signal, the fourth differential amplifier transistor is connected to the fourth pad of the push-pull power amplifier chip, and the fourth pad is wire-bonded to the a second input terminal of the second balun; The first output terminal of the first balun outputs a radio frequency output signal, the second output terminal is connected to the first output terminal of the second balun, and the second output terminal of the second balun is connected to the ground terminal; One end of the tuning circuit is connected to the second output end of the first balun and the first output end of the second balun, and the other end is connected to the ground end; The tuning circuit is configured to tune a common mode signal in the radio frequency output signal. 10. The radio frequency front-end module according to claim 9, wherein the tuning circuit comprises an SMD inductor, or the tuning circuit comprises an SMD resistor.

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