Radio frequency power amplification circuit based on Doherty amplifier

Abstract

The invention provides a radio frequency power amplification circuit suitable for a mobile terminal, and the circuit comprises an input balun module which is configured to receive single-ended radio frequency input and output two paths of differential radio frequency signals; the main power amplifier module is configured to receive one of the two paths of differential radio frequency signals from the input balun module and output a first amplified signal; the auxiliary power amplifier module is configured to receive the other path of differential radio frequency signal in the two paths of differential radio frequency signals from the input balun module and output a second amplified signal; and the output balun module is configured as a balun in the form of a single transformer and is used for receiving the first amplified signal output by the main power amplifier module and the second amplified signal output by the auxiliary power amplifier module and generating a single-ended radio frequency output signal.

Description

Technical Field

[0001] The present invention relates to the field of radio frequency integrated circuits, and in particular to a radio frequency power amplification circuit based on a Doherty amplifier. Background Art

[0002] In 5G communication systems (such as mobile phones or other user devices), RF power amplifiers are key modules and the main power consumption unit modules. In order to improve spectrum utilization and increase communication speed, more and more complex modulation methods such as Orthogonal Frequency Division Multiplexing (OFDM) are adopted by 5G communication systems, and their RF signal peak-to-average ratio (PAR) reaches 7dB to 9dB. When the power amplifier is amplifying power, in order to take into account the linearity of the power amplifier, the RF power amplifier is usually backed off. The larger the RF signal peak-to-average ratio (PAR), the more the RF power amplifier backs off in order to ensure the linearity of the amplified signal, and the correspondingly lower efficiency, resulting in reduced efficiency of the entire wireless communication system, excessive battery consumption of mobile devices, and shortened standby time.

[0003] At present, the solutions for improving the efficiency of power amplifiers in academia and industry are mainly divided into two categories: power supply modulation and load modulation. Power supply modulation is power envelope tracking (ET). Envelope tracking has relatively high requirements on the power supply system. The power supply voltage dynamically follows the changes in the RF signal envelope, which makes envelope tracking more complicated for the system. Compared with envelope tracking (ET), the Doherty structure power amplifier is a load modulation technology. It changes the load impedance at different output power levels through the cooperation of the main amplifier and the auxiliary amplifier. At high power, the impedance is relatively small and has a relatively large power output capacity. At low power, the impedance becomes larger to achieve high efficiency. That is, the Doherty power amplifier can effectively improve the back-off efficiency of the power amplifier and improve the average efficiency of the power amplifier. Doherty power amplifiers are widely used in base stations, and cooperate with the digital pre-distortion (DPD) system to achieve high power, high efficiency and high linearity. In most cases, the Doherty amplifiers used in base stations are built with discrete devices, and the entire power amplifier occupies a large volume.

[0004] With the arrival of 5G, the data transmission speed of the communication system will be further improved, and the peak-to-average ratio of 5G RF signals will be further improved. The efficiency of traditional Class-AB power amplifier circuits is increasingly unable to meet the needs of mobile terminals, and mobile terminals have an increasingly strong demand for high-efficiency and high-linearity power amplifiers. Figure 1 FIG. 1 shows the structure of a conventional Doherty power amplifier. Figure 1 The input network uses a power divider to achieve power distribution, and a quarter-wavelength line is connected in series with the auxiliary path amplification circuit input path to achieve a 90° phase delay. Traditional Doherty power amplifiers are difficult to output higher power due to their limited output power.

[0005] There are two common methods to solve the problem of higher output power: one is to increase the output voltage, and the other is to increase the output current. To increase the output voltage, the battery voltage can be increased by DC-DC conversion, but the increase in voltage makes the power amplifier easy to burn out.

[0006] Therefore, a radio frequency power amplifier circuit that occupies a small space and has high output power is desired. Summary of the invention

[0007] The technical solution of the present invention adopts a transformer-based input balun to output two paths. The transformer-based input balun realizes single-ended to differential conversion, thereby combining the power of two Doherty power amplifiers with a phase difference of 180° to achieve higher power output. The present invention uses the load modulation principle to achieve high back-off efficiency.

[0008] The present invention adopts a multi-chip module to realize a differential synthesis Doherty structure power amplifier, and a quarter-wavelength converter adopts inductor-capacitor equivalence, which reduces the volume of the amplifier, is easy to integrate, and is suitable for use in mobile terminal equipment.

[0009] One aspect of the present invention provides a radio frequency power amplifier circuit, comprising: an input balun module, which is configured to receive a single-ended radio frequency input and output two differential radio frequency signals; a main power amplifier module, which is configured to receive one differential radio frequency signal of the two differential radio frequency signals from the input balun module and output a first amplified signal; an auxiliary power amplifier module, which is configured to receive the other differential radio frequency signal of the two differential radio frequency signals from the input balun module and output a second amplified signal; an output balun module, which is configured to receive the first amplified signal output by the main power amplifier module and the second amplified signal output by the auxiliary power amplifier module, and generate a single-ended radio frequency output signal based on the differential first amplified signal and the second amplified signal.

[0010] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the main power amplifier module includes a first power divider, a first main path amplifier circuit, and a first auxiliary path amplifier circuit, wherein the auxiliary power amplifier module includes a second power divider, a second main path amplifier circuit, and a second auxiliary path amplifier circuit.

[0011] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the main power amplifier module also includes a first driver stage circuit, the input end of the first driver stage circuit is connected to the input balun module, and the output end of the first driver stage circuit is connected to the first power divider, and wherein the auxiliary power amplifier module also includes a second driver stage circuit, the input end of the second driver stage circuit is connected to the input balun module, and the output end of the second driver stage circuit is connected to the second power divider.

[0012] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein a first main path amplifier circuit includes a first main amplifier and a first quarter wavelength converter, an input end of the first main amplifier is connected to a first power divider, and an output end of the first main amplifier is connected to the first quarter wavelength converter, wherein a first auxiliary path amplifier circuit includes a second quarter wavelength converter and a first auxiliary amplifier, one end of the second quarter wavelength converter is connected to a second power divider, and the other end of the second quarter wavelength converter is connected to the input end of the first auxiliary amplifier; wherein a second main path amplifier circuit includes a second main amplifier and a third quarter wavelength converter, an input end of the second main amplifier is connected to the second power divider, and the output end of the second main amplifier is connected to the third quarter wavelength converter, wherein a second auxiliary path amplifier circuit includes a fourth quarter wavelength converter and a second auxiliary amplifier, one end of the fourth quarter wavelength converter is connected to the second power divider, and the other end of the fourth quarter wavelength converter is connected to the input end of the second auxiliary amplifier.

[0013] One aspect of the present invention provides a radio frequency power amplification circuit, wherein each of a first quarter wavelength converter, a second quarter wavelength converter, a third quarter wavelength converter, and a fourth quarter wavelength converter is implemented by a π-type LC network formed by a capacitor and an inductor, and each of the first quarter wavelength converter, the second quarter wavelength converter, the third quarter wavelength converter, and the fourth quarter wavelength converter is configured to perform 90° phase compensation on a signal passing therethrough while achieving impedance modulation at different power outputs.

[0014] One aspect of the present invention provides a radio frequency power amplification circuit, wherein each of a first power divider and a second power divider comprises two π-type LC networks formed by a capacitor and an inductor and a resistor connected between the two π-type LC networks, and each of the first power divider and the second power divider is configured to distribute the power passing therethrough into two paths.

[0015] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein one or more of the first main amplifier, the first auxiliary amplifier, the second main amplifier, and the second auxiliary amplifier are formed by at least one of a BJT transistor, a FET transistor, and a MOS transistor.

[0016] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the input balun module and the output balun module are formed by a ring pattern of a three-layer metal structure.

[0017] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the inductor in each of the first quarter wavelength transformer, the second quarter wavelength transformer, the third quarter wavelength transformer, and the fourth quarter wavelength transformer is formed by a combination of a bonding wire and a substrate microstrip line.

[0018] One aspect of the present invention provides a radio frequency power amplifier circuit, wherein the radio frequency power amplifier is packaged by a multi-layer substrate package for multiple chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram showing a conventional Doherty power amplifier structure;

[0020] Figure 2 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present invention;

[0021] Figure 3 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present invention;

[0022] Figure 4 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present invention;

[0023] Figure 5 is a schematic diagram showing the relationship between the output power and the power-added efficiency (PAE) curve of the Doherty RF power amplifier according to an embodiment of the present invention and the traditional Class AB power amplifier;

[0024] Figure 6 is a schematic diagram showing an implementation of an input balun module T1 according to an embodiment of the present invention;

[0025] Figure 7A-7C is a schematic diagram showing an implementation of an output balun T2 according to an embodiment of the present invention;

[0026] Figure 8is a schematic diagram showing an implementation method of an inductor of a quarter-wavelength transformer in a Doherty radio frequency power amplifier according to an embodiment of the present invention;

[0027] Fig. 9 is a plan view showing a multi-chip package of a Doherty radio frequency power amplifier according to an embodiment of the present invention; and

[0028] Fig.10 is a side view showing a multi-chip package of a Doherty RF power amplifier according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] Before proceeding to the following detailed description, it may be advantageous to set forth the definitions of certain words and phrases used throughout this patent document. The terms "coupling", "connection" and their derivatives refer to any direct or indirect communication or connection between two or more elements, regardless of whether those elements are in physical contact with each other. The terms "transmission", "reception" and "communication" and their derivatives cover direct and indirect communication. The terms "include" and "comprising" and their derivatives refer to including but not limited to. The term "or" is inclusive, meaning and / or. The phrase "associated with..." and its derivatives refer to including, including within, interconnecting, containing, contained within, connecting or connecting with, coupling or coupling with, communicating with, cooperating, interweaving, parallel, close to, binding or binding with, having, having attributes, having a relationship or having a relationship with, etc. The term "controller" refers to any device, system or part thereof that controls at least one operation. Such a controller can be implemented with hardware, or a combination of hardware and software and / or firmware. The functions associated with any particular controller can be centralized or distributed, whether local or remote. The phrase "at least one of", when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one of the items in the list may be required. For example, "at least one of A, B, C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, A and B and C.

[0030] Definitions for other specific words and phrases are provided throughout this patent document. Those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior and future uses of such defined words and phrases.

[0031] In this patent document, the application combination of modules and the division level of sub-modules are only used for illustration, and the application combination of modules and the division level of sub-modules may have different forms without departing from the scope of the present disclosure.

[0032] The technical solution of the present invention adopts a transformer-based input balun to output two paths. The transformer-based input balun realizes single-ended to differential conversion, thereby synthesizing the power of two Doherty power amplifiers with a phase difference of 180° to achieve higher power output. The present invention utilizes the load modulation principle to achieve high back-off efficiency. The present invention adopts a multi-chip module to realize a differential synthesis Doherty structure power amplifier, and the quarter-wavelength converter adopts inductor-capacitor equivalence, which reduces the size of the amplifier, is easy to integrate, and is suitable for use in mobile terminal devices.

[0033] Figure 2 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present invention.

[0034] refer to Figure 2 According to an embodiment of the present invention, the RF power amplifier circuit includes an input balun module T1, a main power amplifier module, an auxiliary power amplifier module, an output balun T2, etc. Among them, the RF input is connected to the main power amplifier module and the auxiliary power amplifier module through the input balun module T1. The input balun module T1 is based on a transformer form, and the input balun module T1 can be configured to receive a single-ended RF input and output two differential RF signals. In addition, the RF power amplifier circuit also includes an input capacitor Cin, which is configured between the two input ends of the input balun module T1. The input capacitor Cin can perform input matching to match the input impedance to a specific impedance, for example, 50Ω.

[0035] The differential output signal output by the input balun module T1 is provided to the main power amplifier module and the auxiliary power amplifier module. The main power amplifier module and the auxiliary power amplifier module can respectively amplify the differential signal with a phase difference of 180° output by the input balun module T1. For example, the main power amplifier module can receive one differential RF signal of the two differential RF signals from the input balun module and output a first amplified signal. The auxiliary power amplifier module can receive the other differential RF signal of the two differential RF signals from the input balun module and output a second amplified signal.

[0036] The output balun module T2 can be configured as a balun in the form of a single transformer, used to realize the differential conversion of the first amplified signal and the second amplified signal to a single-ended output, and output the single-ended output RF output signal through the output balun module T3. The output balun module T3 may include an output balun T2 and a plurality of capacitors. The output balun T2 in the output balun module can receive the first amplified signal output by the main power amplifier module and the second amplified signal output by the auxiliary power amplifier module, and generate a single-ended RF output signal based on the differential first amplified signal and the second amplified signal.

[0037] The multiple capacitors of the output balun module T2 may also include capacitors C1-C3, wherein the capacitor C1 is configured to be connected between an output terminal of the output balun module T2 and the RF output, the capacitor C2 is configured to be connected between another output terminal of the output balun module T2 and the ground node, and the capacitor C3 is configured to be connected between the RF output of the amplifier and the ground node. By outputting through the output balun T2 and multiple capacitors, it is possible to achieve power synthesis while achieving impedance transformation and reduce chip area.

[0038] Figure 3 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present invention.

[0039] refer to Figure 3 The radio frequency power amplifier circuit according to the embodiment of the present invention includes an input balun module T1, a main power amplifier module, an auxiliary power amplifier module, an output balun T2, etc.

[0040] refer to Figure 3 The main power amplifier module may include a first driving stage circuit, a first power divider, a first main path amplifier circuit, and a first auxiliary path amplifier circuit. The auxiliary power amplifier module may include a second driving stage circuit, a second power divider, a second main path amplifier circuit, and a second auxiliary path amplifier circuit.

[0041] The input end of the first driver stage circuit can be connected to the input balun module, and the output end of the first driver stage circuit can be connected to the first power divider. The first power divider may include two π-type LC networks formed by capacitors and inductors and a resistor connected between the two π-type LC networks. The first driver stage circuit can adjust the power of a differential signal (main power amplifier module power) output by the input balun module. In some embodiments, a matching circuit 1 can be connected between the first driver stage circuit and the input balun. The matching circuit 1 can be implemented in the form of an LC network. The matching circuit 1 can be configured to adjust the impedance. The output of the first driver stage circuit can be connected to the input end of the first power divider. In some embodiments, a capacitor C4 can be connected between the first driver stage circuit and the first power divider, and the capacitor C4 can further adjust the impedance to perform impedance matching of the front and rear stages. The first power divider can be configured to distribute the power output by the first driver stage circuit into two paths. One power path (e.g., main path power) distributed by the first power divider can be transmitted to a first main path amplifying circuit including the main amplifier 1, and another power path (e.g., auxiliary path power) distributed by the first power divider can be transmitted to a first auxiliary path amplifying circuit including the auxiliary amplifier 1. The main amplifier 1 can receive the main path power from the first power divider to amplify the main path power. The input end of the main amplifier 1 can be connected to the first power divider. In some embodiments, a matching circuit 2 can be connected between the main amplifier 1 and the first power divider. The matching circuit 2 can be implemented in the form of an LC network. The matching circuit 2 can be configured to adjust the impedance to perform impedance matching of the front and rear stages. The output end of the main amplifier 1 can be connected to a first quarter-wave converter. The first quarter-wave converter can be implemented by a π-type LC network formed by a capacitor and an inductor, and the first quarter-wave converter can be configured to perform 90° phase compensation on the signal passing through it, and at the same time realize impedance modulation at different power outputs. The quarter-wave converter using the LC network has a compact structure, a small footprint, and is easy to integrate. The auxiliary amplifier 1 can receive the auxiliary path power from the first power divider to amplify the auxiliary path power. The input end of the auxiliary amplifier 1 can be connected to a second quarter wavelength converter. One end of the second quarter wavelength converter can be connected to the first power divider, and the other end of the second quarter wavelength converter can be connected to the auxiliary amplifier 1. The second quarter wavelength converter can be implemented by a π-type LC network formed by a capacitor and an inductor, and the second quarter wavelength converter can be configured to perform 90° phase compensation on the signal passing through it, while realizing impedance modulation at different power outputs. In some embodiments, a matching circuit 3 can be connected between the auxiliary amplifier 1 and the second quarter wavelength converter. The matching circuit 3 can be implemented in the form of an LC network. The matching circuit 3 can be configured to adjust the impedance to perform impedance matching of the front and rear stages.The output end of the auxiliary amplifier 1 can be connected to the first quarter wavelength converter to achieve power synthesis of the main power amplifier module. The power synthesized by the main power amplifier module can be used as a differential signal in the input of the output balun T2.

[0042] The input end of the second driver stage circuit can be connected to the input balun module, and the output end of the second driver stage circuit can be connected to the second power divider. The second driver stage circuit can adjust the power of another differential signal (auxiliary power amplifier module power) output by the input balun module. In some embodiments, a matching circuit 4 can be connected between the second driver stage circuit and the input balun. The matching circuit 4 can be implemented in the form of an LC network. The matching circuit 4 can be configured to adjust the impedance to match the impedance of the front and rear stages. The output of the second driver stage circuit can be connected to the input end of the second power divider. In some embodiments, a capacitor C5 can be connected between the second driver stage circuit and the second power divider, and the capacitor C5 can further adjust the impedance to match the impedance of the front and rear stages. The second power divider may include two π-type LC networks formed by capacitors and inductors and a resistor connected between the two π-type LC networks. The second power divider can be configured to distribute the power output by the second driver stage circuit into two paths. One power (e.g., main path power) distributed by the second power divider can be transmitted to a second main path amplifying circuit including the main amplifier 2, and another power (e.g., auxiliary path power) distributed by the second power divider can be transmitted to a second auxiliary path amplifying circuit including the auxiliary amplifier 2. The main amplifier 2 can receive the main path power from the second power divider to amplify the main path power. The input end of the main amplifier 2 can be connected to the second power divider. In some embodiments, a matching circuit 6 can be connected between the main amplifier 2 and the second power divider. The matching circuit 6 can be implemented in the form of an LC network. The matching circuit 6 can be configured to adjust the impedance to perform impedance matching of the front and rear stages. The output end of the main amplifier 2 can be connected to a third quarter wavelength converter. The third quarter wavelength converter can be implemented by a π-type LC network formed by a capacitor and an inductor, and the third quarter wavelength converter can be configured to perform 90° phase compensation on the signal passing through it, while realizing impedance modulation at different power outputs. The auxiliary amplifier 2 can receive the auxiliary path power from the second power divider to amplify the auxiliary path power. The input end of the auxiliary amplifier 2 can be connected to a fourth quarter wavelength converter. One end of the fourth quarter wavelength converter can be connected to the second power divider, and the other end of the fourth quarter wavelength converter can be connected to the auxiliary amplifier 2. The fourth quarter wavelength converter can be implemented by a π-type LC network formed by a capacitor and an inductor, and the fourth quarter wavelength converter can be configured to perform 90° phase compensation on the signal passing through it, while realizing impedance modulation at different power outputs. In some embodiments, a matching circuit 5 can be connected between the auxiliary amplifier 2 and the fourth quarter wavelength converter. The matching circuit 5 can be implemented in the form of an LC network. The matching circuit 5 can be configured to adjust the impedance to perform impedance matching for the front and rear stages. The output end of the auxiliary amplifier 2 can be connected to the third quarter wavelength converter to realize power synthesis of the auxiliary power amplifier module.The power synthesized by the auxiliary power amplifier module can be used as another differential signal in the input of the output balun T2. ​​In some embodiments, a capacitor C6 can be connected between the outputs of the main power amplifier module and the auxiliary power amplifier module to adjust the impedance for impedance matching of the front and rear stages.

[0043] According to an embodiment of the present disclosure, the main amplifier 1 and the main amplifier 2 are configured to operate under the condition of Class AB+deep Class AB bias to achieve better linearity and smoothness.

[0044] The output balun T2 can receive the synthesized power from the main power amplifier module and the auxiliary power amplifier module respectively as two differential signals to generate a single-ended RF output signal.

[0045] The multiple capacitors of the output balun module T2 may also include capacitors C1-C3, wherein the capacitor C1 is configured to be connected between an output terminal of the output balun module T2 and the RF output, the capacitor C2 is configured to be connected between another output terminal of the output balun module T2 and the ground node, and the capacitor C3 is configured to be connected between the RF output of the amplifier and the ground node. By outputting through the output balun T2 and multiple capacitors, it is possible to achieve power synthesis while achieving impedance transformation and reduce chip area.

[0046] In one embodiment, one or more of the main amplifier 1 , the auxiliary amplifier 1 , the main amplifier 2 , and the auxiliary amplifier 2 may be formed by at least one of a BJT transistor, a FET transistor, and a MOS transistor.

[0047] Figure 4 is a schematic diagram showing a radio frequency power amplifier circuit according to an embodiment of the present invention.

[0048] Figure 4 Zhongyu Figure 3 The same components will not be described repeatedly. Figure 4 The RF power amplifier circuit also includes a filter and a switch module to meet the application scenarios of out-of-band suppression and multi-antenna transmission. The filter and the switch module can be connected between the capacitor C1 and the RF output. The filter and the switch module can be connected in series. The filter can filter the signal output by the output balun module T2. The switch module can be configured to switch different antenna ports. Although Figure 6 Not shown, but Figure 6 The Doherty RF power amplifier may further include a control unit, which may be configured to control the bias of the power amplifier and the on-state of the switch module.

[0049] Figure 5Schematic diagram showing the relationship between the output power and the power-added efficiency (PAE) curve of the Doherty RF power amplifier according to an embodiment of the present invention and the conventional Class AB power amplifier. Figure 5 It can be seen that the Doherty RF power amplifier according to the embodiment of the present invention can obtain a higher power added efficiency below 35 dBm output power compared with the traditional Class AB power amplifier.

[0050] Figure 6 is a schematic diagram showing an implementation of an input balun module T1 according to an embodiment of the present invention, and Figure 7A-7C is a schematic diagram showing an implementation of the output balun T2 according to an embodiment of the present invention.

[0051] refer to Figure 6 The input balun module T1 can be formed by a ring pattern formed by three layers of metal, wherein the ring pattern is connected to the ground center by the metal layer 3. Compared with the structure of the traditional power divider and the quarter-wave line, the input balun module T1 according to the embodiment of the present invention formed by three layers of metal is easier to integrate and occupies a smaller volume.

[0052] like Fig. 7A As shown, the output balun T2 can be formed by a pattern of a three-layer metal structure. Figure 7B As shown, the first metal layer may include a circular shape with an upper portion being open and a lower portion extending downward. Figure 7B The pattern in can correspond to the input winding of the output balun T2. Figure 7C As shown, the second metal layer may include an arc pattern, and the third metal layer may include a pattern that connects the arc pattern in the second metal layer at a connection region. Figure 7C The pattern in can correspond to the output winding in the output balun.

[0053] Figure 8 is a schematic diagram showing an implementation of an inductor of a quarter-wavelength transformer in a Doherty RF power amplifier according to an embodiment of the present invention. Fig.10 In order to reduce the area and cost of the entire module, the inductor in the quarter-wavelength transformer can be realized by a combination of bonding wires and substrate microstrip lines.

[0054] Fig. 9 is a plan view showing a multi-chip package of a Doherty RF power amplifier according to an embodiment of the present invention, and Fig.10 is a side view showing a multi-chip package of a Doherty RF power amplifier according to an embodiment of the present invention.

[0055] Multi-Chip Module Doherty structure power amplifiers are gradually being used in mobile terminals. Fig. 9 and Fig.10 , multiple chips (e.g., controller, power amplifier, low noise amplifier, switch module, output balun module) are integrated into a module through a multi-layer substrate, and multiple chips can be interconnected through bonding wires. For example, refer to Fig.10 The power amplifier chip and the output balun module are interconnected by bonding wires. By adopting a multi-chip integrated module structure, the Doherty power amplifier according to the embodiment of the present invention can be further applied to a mobile terminal.

[0056] Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. The present disclosure is intended to encompass such changes and modifications as fall within the scope of the appended claims.

[0057] Any description in the present invention should not be construed as implying that any particular element, step, or function is an essential element that must be included in the claims scope. The scope of the patented subject matter is limited solely by the claims.

Claims

1. A radio frequency power amplifier circuit, comprising: An input balun module configured to receive a single-ended RF input and output two differential RF signals; A main power amplifier module, configured to receive one of the two differential RF signals from the input balun module and output a first amplified signal; an auxiliary power amplifier module, configured to receive another differential RF signal of the two differential RF signals from the input balun module and output a second amplified signal; The output balun module is configured to receive the first amplified signal output by the main power amplifier module and the second amplified signal output by the auxiliary power amplifier module, and generate a single-ended RF output signal based on the differential first amplified signal and the second amplified signal.

2. The radio frequency power amplifier circuit according to claim 1, wherein: The main power amplifier module includes a first power divider, a first main path amplifier circuit, and a first auxiliary path amplifier circuit. The auxiliary power amplifier module includes a second power divider, a second main path amplifier circuit, and a second auxiliary path amplifier circuit.

3. The radio frequency power amplifier circuit according to claim 2, wherein: The main power amplifier module further includes a first driver stage circuit, an input end of the first driver stage circuit is connected to the input balun module, an output end of the first driver stage circuit is connected to the first power divider, and The auxiliary power amplifier module further includes a second driving stage circuit, an input end of the second driving stage circuit is connected to the input balun module, and an output end of the second driving stage circuit is connected to the second power divider.

4. The radio frequency power amplifier circuit according to claim 2, wherein: The first main path amplification circuit includes a first main amplifier and a first quarter wavelength converter, wherein the input end of the first main amplifier is connected to the first power divider, and the output end of the first main amplifier is connected to the first quarter wavelength converter. The first auxiliary path amplification circuit includes a second quarter-wave converter and a first auxiliary amplifier, one end of the second quarter-wave converter is connected to the second power divider, and the other end of the second quarter-wave converter is connected to the input end of the first auxiliary amplifier; The second main path amplification circuit includes a second main amplifier and a third quarter-wavelength converter, the input end of the second main amplifier is connected to the second power divider, and the output end of the second main amplifier is connected to the third quarter-wavelength converter. The second auxiliary path amplification circuit includes a fourth quarter-wave converter and a second auxiliary amplifier, one end of the fourth quarter-wave converter is connected to the second power divider, and the other end of the fourth quarter-wave converter is connected to the input end of the second auxiliary amplifier.

5. The radio frequency power amplifier circuit according to claim 4, wherein: Each of the first quarter wavelength converter, the second quarter wavelength converter, the third quarter wavelength converter, and the fourth quarter wavelength converter is implemented by a π-type LC network formed by a capacitor and an inductor, and each of the first quarter wavelength converter, the second quarter wavelength converter, the third quarter wavelength converter, and the fourth quarter wavelength converter is configured to perform 90° phase compensation on the signal passing therethrough and simultaneously achieve impedance modulation at different power outputs.

6. The radio frequency power amplifier circuit according to claim 2, wherein: Each of the first power divider and the second power divider includes two π-type LC networks formed of a capacitor and an inductor and a resistor connected between the two π-type LC networks, and each of the first power divider and the second power divider is configured to divide power passing therethrough into two paths.

7. The radio frequency power amplifier circuit according to claim 4, wherein: One or more of the first main amplifier, the first auxiliary amplifier, the second main amplifier, and the second auxiliary amplifier are formed by at least one of a BJT transistor, a FET transistor, and a MOS transistor.

8. The radio frequency power amplifier circuit according to claim 1, wherein: The input balun module and the output balun module are formed by a ring pattern of a three-layer metal structure.

9. The radio frequency power amplifier circuit according to claim 4 or 5, wherein: The inductor in each of the first quarter-wave transformer, the second quarter-wave transformer, the third quarter-wave transformer, and the fourth quarter-wave transformer is formed by a combination of a bonding wire and a substrate microstrip line.

10. The radio frequency power amplifier circuit according to claim 1, wherein: The radio frequency power amplifier is packaged through a multi-layer substrate package for multiple chips.

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