A wideband power amplifier circuit

Abstract

The application provides a broadband power amplifier circuit, comprising a broadband DC conversion module, a distributed broadband power amplifier module, a reference module and a constant current source module, wherein the broadband DC conversion module processes an input signal according to a reference voltage to generate an intermediate signal with a precisely set DC bias; the distributed broadband power amplifier module cascades and amplifies the intermediate signal to realize distortionless and full-band power amplification of the input signal from DC to high frequency components; the global linkage of the reference module and the stable power supply of the constant current source module ensure the high stability and linearity of the amplifier operating point, and the independent bias adjustment end is used to flexibly adjust and control the DC bias of the final output signal. The application realizes effective power amplification of the full-band input signal containing DC components, has adjustable output DC level, and significantly widens the working bandwidth and application flexibility of the amplifier.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, specifically to a broadband power amplifier circuit. Background Technology

[0002] Wideband power amplifiers are key components in modern electronic systems. Their main function is to amplify weak input signals into output signals with sufficient power over a wide frequency range. They have indispensable applications in many fields such as wireless communication, radar detection, test and measurement, and broadcasting, and are an important link connecting signal sources to radiating elements (such as antennas) or loads.

[0003] To achieve broadband amplification and ensure circuit stability, and to avoid interference and damage to the amplifier's operating state caused by DC bias, existing broadband power amplifiers generally employ AC coupling structures (such as DC blocking capacitors) in the input and output stages. This AC coupling structure aims to block DC components and extremely low-frequency elements in the signal, preventing potential DC bias voltages in the preceding circuitry from affecting or interfering with the amplifier's operating point setting, thereby ensuring stable and efficient operation of the amplifier within the designed RF, microwave, and other AC frequency bands.

[0004] However, since the AC coupling structure essentially constitutes a high-pass filter, it inevitably attenuates or completely blocks DC and low-frequency signals with frequencies close to DC. This directly results in traditional broadband power amplifiers being unable to amplify DC signals, and the lower limit of their effective operating frequency band cannot be extended to DC. Secondly, even in some applications where the amplifier needs to process DC components, the DC bias of its output signal is usually determined by the amplifier's internal fixed bias network, making it difficult to make flexible and precise external adjustments according to the specific needs of subsequent circuits or loads. This greatly limits the application flexibility and system integration of power amplifiers. Therefore, with the development of system technology, existing broadband power amplifiers cannot meet the demand in some scenarios for power amplifiers capable of seamlessly processing and amplifying signals across the entire frequency band starting from DC, and possessing output DC bias adjustment capabilities. Summary of the Invention

[0005] This application provides a broadband power amplifier circuit that can solve the technical problems of traditional broadband power amplifiers in the prior art, which cannot effectively amplify DC and extremely low frequency signals due to the common use of AC coupling design, and whose output DC bias is difficult to adjust flexibly, thus limiting their application.

[0006] In a first aspect, embodiments of this application provide a broadband power amplifier circuit, including:

[0007] A broadband DC-DC converter module includes an input terminal, a reference voltage input terminal, and an output terminal. The input terminal of the broadband DC-DC converter module is used to receive an input signal, and the reference voltage input terminal is used to receive a reference voltage. The broadband DC-DC converter module is used to perform broadband DC-DC conversion on the received input signal according to the reference voltage, generate a DC bias intermediate signal based on the reference voltage, and output it through its output terminal.

[0008] A distributed broadband power amplifier module includes an input terminal, a bias adjustment terminal, an output terminal, and several power amplification units cascaded between the input terminal and the output terminal. The input terminal of the distributed broadband power amplifier module is used to receive the intermediate signal output by the broadband DC-DC converter module, and the bias adjustment terminal is used to receive a preset DC bias adjustment voltage. The distributed broadband power amplifier module is used to amplify the intermediate signal stage by stage through the several power amplification units under the drive of the intermediate signal, and adjust the DC bias of the amplified output signal according to the DC bias adjustment voltage.

[0009] In some embodiments, the broadband power amplifier circuit further includes a reference module; the reference module has an input terminal and an output terminal, and the input terminal of the reference module is connected to the output terminal of the distributed broadband power amplifier module;

[0010] The reference module is used to generate the reference voltage based on the voltage at the output of the distributed broadband power amplifier module, and simultaneously provide the reference voltage to the reference voltage input of the broadband DC-DC converter module and the common connection point of the source of each field-effect transistor in the power amplifier unit.

[0011] In some embodiments, the reference module includes an amplifier circuit;

[0012] The amplifier circuit is used to sum and amplify the output voltage of the distributed broadband power amplifier module with a first reference voltage obtained from an external source, and output the reference voltage.

[0013] In some embodiments, the amplification circuit includes resistors R26, R27, and R29, operational amplifier U6, resistor R28, and capacitor C6;

[0014] The first end of resistor R26 is connected to the input terminal of the reference module; the first end of resistor R27 is used to receive the first reference voltage; the first end of resistor R29 is connected to the ground terminal, and the second end of resistor R29 is connected to the second end of resistor R26; the non-inverting input terminal of operational amplifier U6 is connected to the second end of resistor R26, the inverting input terminal of operational amplifier U6 is connected to the second end of resistor R27, and the output terminal of operational amplifier U6 is connected to the output terminal of the reference module; resistor R28 and capacitor C6 are connected in parallel and are connected across the inverting input terminal and the output terminal of operational amplifier U6.

[0015] In some embodiments, the broadband DC-DC converter module includes a low-frequency I / V circuit, an AC coupling circuit, a low-frequency amplifier circuit, and a low-frequency superposition circuit;

[0016] The low-frequency I / V circuit is used to receive the input signal, sample the low-frequency current component in the input signal, and convert it into a first low-frequency voltage signal; the AC coupling circuit is used to receive the input signal after current sampling by the low-frequency I / V circuit, and filter the DC and low-frequency components in the signal to output a high-frequency signal; the low-frequency amplification circuit is used to receive the input signal and the first low-frequency voltage signal, and sum and amplify the input signal and the first low-frequency voltage signal to generate a second low-frequency voltage signal; the low-frequency superposition circuit is used to receive the second low-frequency voltage signal, amplify the second low-frequency voltage signal, and output it to the output terminal of the AC coupling circuit, where it is superimposed with the high-frequency signal to generate the intermediate signal.

[0017] In some embodiments, the low-frequency I / V circuit includes a sampling resistor RI, a resistor R1, a resistor R4, an operational amplifier U1, a resistor R2, and a resistor R3;

[0018] The first end of the current sampling resistor R1 is used to receive the input signal, and the second end of the current sampling resistor R4 is used to output the current-sampled input signal; the first end of resistor R1 is connected to the first end of the current sampling resistor R1; the first end of resistor R4 is connected to the second end of the current sampling resistor R1; the non-inverting input of operational amplifier U1 is connected to the second end of resistor R1, the inverting input of operational amplifier U1 is connected to the second end of resistor R4, and the output of operational amplifier U1 is used to output the first low-frequency voltage signal; the first end of resistor R2 is connected to the ground terminal, and the second end of resistor R2 is connected to the second end of resistor R1; the first end of resistor R3 is connected to the second end of resistor R4, and the second end of resistor R4 is connected to the output of operational amplifier U3.

[0019] In some embodiments, the AC coupling circuit includes a high-pass filter network; wherein the high-pass filter network is a capacitor, an RC high-pass filter, or an active filter circuit with high-pass characteristics.

[0020] In some embodiments, the low-frequency amplifier circuit includes resistors R5, R6, and R7, a DC voltage source, resistor R16, operational amplifier U2, and resistor R8;

[0021] The first end of resistor R5 is connected to the second input terminal of the low-frequency amplification module; the first end of resistor R6 is used to receive the input signal, and the second end of resistor R6 is connected to the second end of resistor R5; the first end of resistor R7 is used to receive the reference voltage, and the second end of resistor R7 is connected to the second end of resistor R6; the DC voltage source is used to generate a second reference voltage; the first end of resistor R16 is connected to the positive terminal of the DC voltage source to obtain the second reference voltage, and the second end of resistor R16 is connected to the second end of resistor R7; the inverting input terminal of operational amplifier U2 is connected to the second end of resistor R6, the non-inverting input terminal of operational amplifier U2 is connected to the ground terminal, and the output terminal of operational amplifier U2 is used to output the second low-frequency signal; resistor R8 is connected between the output terminal and the inverting input terminal of operational amplifier U2.

[0022] In some embodiments, the low-frequency superposition circuit includes resistors R9 and R10, operational amplifier U3, resistor R11, and at least one set of low-frequency compensation networks;

[0023] The first terminal of resistor R9 is used to receive the second low-frequency voltage signal; the first terminal of resistor R10 is connected to the second terminal of resistor R9; the non-inverting input terminal of operational amplifier U3 is connected to the ground terminal, and the inverting input terminal of operational amplifier U3 is connected to the second terminal of resistor R9; the first terminal of resistor R11 is connected to the output terminal of operational amplifier U3, and the second terminal of resistor R11 is connected to the second terminal of resistor R10, for outputting the amplified second low-frequency voltage signal;

[0024] The low-frequency compensation network is used to compensate for low-frequency distortion in the second low-frequency voltage signal.

[0025] In some embodiments, the low-frequency compensation network includes a first low-frequency compensation network, a second low-frequency compensation network, and a third low-frequency compensation network;

[0026] The first low-frequency compensation network includes a capacitor C4 and a resistor R15; the first end of the capacitor C4 is connected to the first end of the resistor R9; the first end of the resistor R15 is connected to the second end of the capacitor C4, and the second end of the resistor R15 is connected to the second end of the resistor R9.

[0027] The second low-frequency compensation network includes capacitor C3, resistor R13, and resistor R14; the first terminal of capacitor C3 is connected to the inverting input terminal of operational amplifier U3; the first terminal of resistor R13 is connected to the second terminal of capacitor C3, and the second terminal of resistor R13 is connected to the output terminal of operational amplifier U3; the first terminal of resistor R14 is connected to the second terminal of capacitor C3, and the second terminal of resistor R14 is connected to the ground terminal.

[0028] The third low-frequency compensation network includes a capacitor C2 and a resistor R12; the first end of the resistor R12 is connected to the output terminal of the operational amplifier U3, and the second end of the resistor R12 is connected to the first end of the resistor R11; the first end of the capacitor C2 is connected to the first end of the resistor R11, and the second end of the capacitor C2 is connected to the ground terminal.

[0029] In some embodiments, the broadband power amplifier circuit further includes a constant current source module; the constant current source module includes a power input terminal, a control terminal, and an output terminal; the constant current source module is used to generate a constant current according to the external voltage received at the power input terminal, provide operating current to the distributed broadband power amplifier module through its output terminal, and adjust the magnitude of the operating current according to the control signal received at the control terminal.

[0030] In some embodiments, the constant current source module includes resistors R19, R20, R21, and R22, operational amplifier U4, resistors R23, R24, and R25, operational amplifier U5, capacitor C5, transistor QA, and inductor L1.

[0031] The first end of resistor R19 is connected to the power input terminal; the first end of resistor R20 is connected to the first end of resistor R19; the first end of resistor R22 is connected to the ground terminal, and the second end of resistor R22 is connected to the second end of resistor R20; the first end of resistor R21 is connected to the second end of resistor R19; the non-inverting input terminal of operational amplifier U4 is connected to the second end of resistor R20, and the inverting input terminal of operational amplifier U4 is connected to the second end of resistor R21; the first end of resistor R23 is connected to the inverting input terminal of operational amplifier U4, and the second end of resistor R23 is connected to the output terminal of operational amplifier U4; the first end of resistor R24 ​​is connected to the second end of resistor R23. The circuit consists of the following terminals: The first terminal of resistor R25 is used to receive the control signal, and the second terminal of resistor R25 is connected to the second terminal of resistor R24; the non-inverting input terminal of operational amplifier U5 is connected to the ground terminal, and the inverting input terminal of operational amplifier U5 is connected to the second terminal of resistor R25; the first terminal of capacitor C5 is connected to the second terminal of resistor R24, and the second terminal of capacitor C5 is connected to the output terminal of operational amplifier U5; the control terminal of transistor QA is connected to the output terminal of operational amplifier U5, and the first terminal of transistor QA is connected to the second terminal of resistor R19; the first terminal of inductor L1 is connected to the second terminal of transistor QA, and the second terminal of inductor L1 is used to output the operating current.

[0032] The broadband power amplifier circuit provided in this application includes a broadband DC-DC converter module, a distributed broadband power amplifier module, a reference module, and a constant current source module, constructing a complete signal processing and amplification chain. The broadband DC-DC converter module processes the input signal according to a reference voltage, generating an intermediate signal with a precisely set DC bias. The distributed broadband power amplifier module then cascades and amplifies this intermediate signal, achieving distortion-free, full-band power amplification of the input signal from DC to high-frequency components. Furthermore, the global linkage of the reference module and the stable power supply of the constant current source module ensure extremely high stability and linearity of the amplifier's operating point. An independent bias adjustment terminal allows for flexible control of the DC bias of the final output signal. Compared to traditional broadband power amplifiers, this circuit achieves effective power amplification of the full-band input signal, including DC components, and has adjustable output DC level, significantly broadening the amplifier's operating bandwidth and application flexibility. Attached Figure Description

[0033] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0034] Figure 1 This is a schematic diagram of the structure of a broadband power amplifier circuit provided in one embodiment of this application.

[0035] Figure 2 This is a schematic diagram of a broadband power amplifier circuit provided in another embodiment of this application.

[0036] Figure 3 A circuit diagram of a reference module provided for one embodiment of this application.

[0037] Figure 4 This is a circuit diagram of a distributed broadband power amplifier module provided in one embodiment of this application.

[0038] Figure 5 This is a schematic diagram of the structure of a broadband DC-DC converter module provided in one embodiment of this application.

[0039] Figure 6 This is a circuit diagram of a low-frequency I / V circuit provided in one embodiment of this application.

[0040] Figure 7 This is a schematic diagram of the structure of an AC coupling circuit provided in one embodiment of this application.

[0041] Figure 8 This is a circuit diagram of a low-frequency amplifier circuit provided in one embodiment of this application.

[0042] Figure 9 This is a circuit diagram of a low-frequency superposition circuit provided in one embodiment of this application.

[0043] Figure 10 This is a schematic diagram of a broadband power amplifier circuit provided in another embodiment of this application.

[0044] Figure 11 This is a circuit diagram of a constant current source module provided in one embodiment of this application.

[0045] Figure 12 A complete circuit diagram of a broadband power amplifier circuit provided in one embodiment of this application.

[0046] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0047] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0048] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0049] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship. Unless otherwise specified, the terms "connection" and "linkage" used in this application include both direct and indirect connections (linkages).

[0050] As a critical link in the signal chain, the performance of a broadband power amplifier directly affects the bandwidth, linearity, and output capability of the entire system. Traditional broadband amplifiers typically rely on AC coupling to block DC, resulting in their inability to amplify DC and extremely low-frequency signals, and their output DC bias is difficult to adjust flexibly. This application proposes an improved power amplifier circuit that, by introducing a broadband DC-DC conversion module 10 and a distributed amplification structure, not only achieves full-band signal amplification from DC to high frequencies but also possesses adjustable output DC bias, thereby significantly improving the amplifier's applicability and system integration flexibility.

[0051] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0052] Figure 1 This is a schematic diagram of a broadband power amplifier circuit provided in one embodiment of this application. Figure 1 As shown, the broadband power amplifier circuit provided in this embodiment includes a broadband DC-DC converter module 10 and a distributed broadband power amplifier module 20.

[0053] In this embodiment, the broadband DC-DC converter module 10 includes an input terminal, a reference voltage input terminal, and an output terminal. Its input terminal is connected to the output terminal of the preceding device and is used to receive the input signal output by the preceding device. The reference voltage input terminal is used to receive an externally provided reference voltage. The broadband DC-DC converter module 10 performs broadband DC-DC conversion on the received input signal based on the acquired reference voltage, generates a DC bias intermediate signal based on the reference voltage, and outputs it through its output terminal.

[0054] Understandably, the broadband DC-DC converter module 10 is a key pre-processing unit for the broadband power amplifier to amplify DC and low-frequency signals. Its core function is to perform "broadband DC-DC conversion" on the input signal, that is, while coupling and transmitting the AC component in the input signal, it actively and accurately sets the DC bias level of the output intermediate signal according to an externally provided reference voltage. In this process, the DC bias in the input signal of the previous stage is effectively isolated, preventing it from interfering with the stable operating point of the subsequent amplifier; at the same time, it also pre-establishes a correct operating bias voltage for the subsequent distributed broadband power amplifier module 20 that is compatible with its reference system, thus laying the necessary foundation for the amplification of signals across the entire frequency band starting from DC.

[0055] The distributed broadband power amplifier module 20 includes an input terminal, a bias adjustment terminal, an output terminal, and several power amplification units cascaded between the input and output terminals. The input terminal of the distributed broadband power amplifier module 20 is connected to the output terminal of the broadband DC-DC converter module 10 to receive its output intermediate signal. The bias adjustment terminal receives a preset DC bias adjustment voltage input from an external source. Driven by the intermediate signal output from the broadband DC-DC converter module 10, the distributed broadband power amplifier module 20 amplifies the intermediate signal stage by stage through several power amplification units and adjusts the DC bias of the amplified output signal according to the DC bias adjustment voltage, thereby achieving adjustable output DC bias.

[0056] Understandably, the distributed broadband power amplifier module 20 is fundamental to the amplification of the broadband power amplifier. Employing a distributed structure with cascaded multi-stage power amplifier units, it can provide high gain and high power output over an extremely wide frequency range. In this embodiment, it receives an intermediate signal with a pre-set DC bias from the broadband DC-DC converter module 10 and amplifies it stage by stage. Specifically, this module has an independent bias adjustment terminal. By applying an externally preset DC bias adjustment voltage, the DC level of the final output signal can be directly and flexibly controlled. This allows the power amplifier to amplify signals not only from DC to high frequencies but also to adapt its output DC bias to the level requirements of different downstream devices or systems, greatly enhancing the circuit's applicability and flexibility in system integration.

[0057] Figure 2 This is a schematic diagram of a broadband power amplifier circuit provided in another embodiment of this application. Figure 2 As shown, the broadband power amplifier circuit provided in this embodiment, based on the above embodiment, also includes a reference module 30.

[0058] In this embodiment, the reference module 30 has an input terminal, a first output terminal, and a second output terminal. Its input terminal is connected to the output terminal of the distributed broadband power amplifier module 20, its first output terminal is connected to the reference voltage input terminal of the broadband DC-DC converter module 10, and its second output terminal is connected to the common source connection point of each field-effect transistor in the power amplification units of the distributed broadband power amplifier module 20. The reference module 30 is used to generate a reference voltage based on the voltage at the output terminal of the distributed broadband power amplifier module 20, and simultaneously provide this reference voltage to both the reference voltage input terminal of the broadband DC-DC converter module 10 and the common source connection point of each field-effect transistor in the power amplification units.

[0059] Understandably, in this broadband power amplifier circuit, the reference module 30 generates a reference voltage associated with the final output voltage of the power amplifier by sampling it in real time. This reference voltage is simultaneously fed to two key nodes: first, it is sent back to the broadband DC-DC converter module 10 as a precise basis for setting the DC bias of the intermediate output signal, thereby achieving pre-calibration of the operating point at the front end of the signal chain; second, it is directly provided to the common source of all distributed amplification transistors, allowing their source potential to "float" with the output voltage. The reference module 30 establishes a global, interconnected voltage reference system, which ensures that the effective drive voltage (Vgs) applied between the gate and source of each amplification transistor is highly stable. This ensures that the effective drive voltage of the amplifier can be locked regardless of changes in the output load or signal amplitude, thereby guaranteeing the consistency and linearity of amplification performance across the entire range from DC to high frequency.

[0060] In some embodiments, the reference module 30 includes an amplification circuit; the differential amplification circuit is used to sum and amplify the output voltage of the distributed broadband power amplifier module 20 with a first reference voltage obtained from an external source, and output the difference as a reference voltage.

[0061] Understandably, the amplifier circuit sums and amplifies the real-time voltage at the output of the distributed broadband power amplifier module 20 with the first reference voltage to form the required reference voltage. This summation amplification ensures that the reference voltage follows the DC level changes of the final output voltage of the power amplifier, while maintaining a constant offset determined by the first reference voltage. This allows the reference voltage to dynamically and accurately respond to the output state, providing a stable and reliable floating bias reference for the entire amplification system. This is crucial for maintaining excellent linearity and operating point stability across the entire frequency range (especially in the DC and low-frequency ranges).

[0062] Figure 3 A circuit diagram of a reference module provided for one embodiment of this application. (See diagram below.) Figure 3 As shown, in this embodiment, the reference module 30 provides a reference voltage using a differential discharge circuit, and the amplifier circuit includes resistors R26, R27, and R29, operational amplifier U6, resistor R28, and capacitor C6.

[0063] Specifically, the first end of resistor R26 is connected to the input terminal of reference module 30; the first end of resistor R27 is used to receive the first reference voltage generated by a voltage source; the first end of resistor R29 is connected to the ground terminal, and the second end of resistor R29 is connected to the second end of resistor R26; the non-inverting input terminal of operational amplifier U6 is connected to the second end of resistor R26, the inverting input terminal of operational amplifier U6 is connected to the second end of resistor R27, and the output terminal of operational amplifier U6 is connected to the output terminal of reference module 30; resistor R28 and capacitor C6 are connected in parallel and are connected across the inverting input terminal and the output terminal of operational amplifier U6.

[0064] In summary, the broadband power amplifier circuit provided in any of the above embodiments processes the input signal according to a reference voltage through a broadband DC-DC conversion module to generate an intermediate signal with a precisely set DC bias. This intermediate signal is then cascaded and amplified by distributed broadband power amplifier modules, and the DC bias of the final output signal is flexibly controlled via an independent bias adjustment terminal. Compared to traditional broadband power amplifiers, this circuit achieves effective power amplification of input signals across the entire frequency band, including DC components, and possesses adjustable output DC levels, significantly broadening the amplifier's operating bandwidth and application flexibility.

[0065] To fundamentally overcome the technical shortcomings of traditional broadband power amplifiers, which cannot operate in the DC and extremely low frequency ranges due to DC blocking design and have a fixed output DC bias, the key lies in the signal processing before signal amplification. This process must couple the broadband AC signal and intelligently reconstruct and set the correct DC operating point based on the system reference. The following will describe in detail, with reference to the accompanying drawings, the signal transmission process from DC to high-frequency components in the input signal by the broadband DC-DC conversion module 10.

[0066] Figure 4 This is a circuit diagram of a distributed broadband power amplifier module provided in one embodiment of this application. Figure 4 As shown, the distributed broadband power amplifier module 20 provided in this embodiment includes an input terminal, a bias adjustment terminal, a reference voltage terminal, an output terminal, and multiple power amplification units cascaded between its input terminal and output terminal.

[0067] Specifically, the input terminal of the distributed broadband power amplifier module 20 is connected to the output terminal of the broadband DC-DC conversion module 10 to receive the intermediate signal that has been set to DC bias, and its output terminal serves as the final signal output port of the entire circuit. Each power amplifier unit typically contains an amplifying transistor (i.e., field-effect transistors Q1, Q2, ..., Qn). The control terminals (gates) of all transistors are connected to the input terminal of this module, and the first terminal (drain) of their output current paths is connected to the output terminal of this module.

[0068] Specifically, the module also has an independent bias adjustment terminal for receiving an externally provided DC bias adjustment voltage, which is connected to the first terminal (drain) of the transistor through a resistor R17. Its DC bias is transmitted to the signal output through the resistor R17 to precisely control the DC level of the output signal; and a reference voltage terminal for receiving the reference voltage provided by the reference module 30, which is connected to the second terminal (source) of all transistors through a resistor R18.

[0069] This cascaded parallel structure not only provides high gain and wide bandwidth characteristics, but also enables the entire module to linearly amplify complete signals from DC to high frequency at a stable operating point established by the intermediate signal. At the same time, the output bias can be flexibly set by external voltage adjustment, thus perfectly adapting to the needs of the subsequent circuit.

[0070] Figure 5 This is a schematic diagram of the structure of a broadband DC-DC converter module provided in one embodiment of this application. Figure 5 As shown, the broadband DC-DC conversion module 10 provided in this embodiment includes a low-frequency I / V circuit 101, an AC coupling circuit 102, a low-frequency amplifier circuit 103, and a low-frequency superposition circuit 104.

[0071] In this embodiment, the low-frequency I / V circuit 101 includes an input terminal, a first output terminal, and a second output terminal. Its input terminal is used to receive the input signal provided by the preceding device. The low-frequency I / V circuit 101 is used to sample the low-frequency current component in the input signal and convert it into a first low-frequency voltage signal. After sampling, the sampled input signal is output through the first output terminal, and the first low-frequency voltage signal is output through the second output terminal.

[0072] Understandably, the low-frequency I / V circuit 101 receives the raw input signal from the preceding stage, which contains DC, low-frequency, and high-frequency components. It samples the low-frequency current component (including DC) in the input signal through circuitry and converts it into a corresponding first low-frequency voltage signal. After sampling, it outputs the sampled current signal through the first output terminal and the first low-frequency voltage signal through the second output terminal.

[0073] In this embodiment, the AC coupling circuit 102 includes an input terminal and an output terminal. Its input terminal is connected to the first output terminal of the low-frequency I / V circuit 101, and is used to receive the input signal after current sampling by the low-frequency I / V circuit 101, and filter the DC and low-frequency components in the signal to output a high-frequency signal.

[0074] It is understandable that the function of the AC coupling circuit 102 is to receive the input signal after it has been sampled by the low-frequency I / V circuit 101, and to filter the DC and low-frequency components in the signal, thereby outputting a high-frequency signal containing only high-frequency components. This achieves the initial separation of different frequency components in the signal. In other words, the AC coupling circuit 102 can completely eliminate the influence of the DC bias of the preceding devices on the subsequent stage, providing a clean high-frequency foundation for subsequent signal superposition.

[0075] In this embodiment, the low-frequency amplifier circuit 103 includes a first input terminal, a second input terminal, and an output terminal. The first input terminal is used to receive the input signal output by the preceding device. The second input terminal is connected to the second output terminal of the low-frequency I / V circuit 101 and is used to receive the first low-frequency voltage signal output by the circuit. The low-frequency amplifier circuit 103 is used to sum and amplify the received input signal and the first low-frequency voltage signal to generate a second low-frequency voltage signal, which is then output by its output terminal.

[0076] Understandably, the two input terminals of the low-frequency amplifier circuit 103 receive the original input signal from the preceding stage (as a voltage reference) and the first low-frequency voltage signal, respectively. The circuit then sums and amplifies these two signals to generate the second low-frequency voltage signal. This amplification process not only compensates for potential losses in the low-frequency signal path but, more importantly, allows the circuit to flexibly set new and appropriate DC bias levels according to the needs of subsequent devices, while simultaneously independently adjusting the low-frequency gain, preparing for the superposition of the low-frequency and high-frequency signals.

[0077] In this embodiment, the low-frequency superposition circuit 104 includes an input terminal and an output terminal. Its input terminal is connected to the output terminal of the low-frequency amplifier circuit 103 for receiving a second low-frequency voltage signal, and its output terminal is connected to the output terminal of the AC coupling circuit 102. The low-frequency superposition circuit 104 amplifies the received second low-frequency voltage signal and outputs it to the output terminal of the AC coupling circuit 102. At the output terminal, it superimposes the signal with a high-frequency signal to form an intermediate signal at the output terminal of the AC coupling circuit 102, which is then output to subsequent devices.

[0078] Understandably, the low-frequency superposition circuit 104 receives the second low-frequency voltage signal from the low-frequency amplifier circuit 103 after processing and level shifting. After amplifying the received second low-frequency voltage signal through circuit construction, it is directly output to the output terminal of the AC coupling circuit 102. Before the output, the recovered and reconstructed low-frequency / DC component is superimposed with the unprocessed high-frequency signal, and finally a complete, spectrum-seamless broadband intermediate signal is formed at the output terminal of the AC coupling circuit 102.

[0079] In some embodiments, the low-frequency I / V circuit 101 includes at least a sampling resistor RI, an operational amplifier U1, and a feedback resistor network connected in parallel between the input and output terminals of the operational amplifier U1.

[0080] The current sampling resistor RI is connected in series between the input terminal and the first output terminal of the low-frequency I / V circuit 101 to sample the low-frequency current component in the input signal; the two input terminals of the operational amplifier U1 are respectively connected to the two ends of the current sampling resistor RI to convert the current signal flowing through the current sampling resistor RI into a voltage signal and output it; the feedback resistor network is used to set the conversion gain and frequency response of the low-frequency signal.

[0081] The sampling resistor RI is connected in series in the main signal path. All current of the input signal (including low-frequency components) flows through it. The low-frequency current component is indirectly acquired by detecting the voltage across its terminals. The operational amplifier U1 is connected in parallel across the sampling resistor RI with its high input impedance. It can detect the voltage drop across the sampling resistor RI and convert the difference (representing the current signal) into a voltage signal. The feedback resistor network (usually composed of a combination of resistors and / or capacitors) connected between the input and output terminals of the operational amplifier U1 sets the gain and frequency response characteristics of the current-to-voltage converter. This ensures that only specific low-frequency components are effectively sampled and converted into a first low-frequency voltage signal output from the second output terminal, while allowing the main signal current to continue flowing to the first output terminal through the sampling resistor RI with essentially no attenuation.

[0082] Figure 6 This is a circuit diagram of a low-frequency I / V circuit provided in one embodiment of this application. Figure 6 As shown, the low-frequency I / V circuit 101 provided in this embodiment includes a current sampling resistor RI, a resistor R1, a resistor R4, an operational amplifier U1, a resistor R2, and a resistor R3.

[0083] Specifically, the first terminal of the current sampling resistor RI is used to receive the input signal, and the second terminal of the current sampling resistor R4 is used to output the current-sampled input signal; the first terminal of resistor R1 is connected to the first terminal of the current sampling resistor RI; the first terminal of resistor R4 is connected to the second terminal of the current sampling resistor RI; the non-inverting input terminal of operational amplifier U1 is connected to the second terminal of resistor R1, the inverting input terminal of operational amplifier U1 is connected to the second terminal of resistor R4, and the output terminal of operational amplifier U1 is used to output the first low-frequency voltage signal; the first terminal of resistor R2 is connected to the ground terminal, and the second terminal of resistor R2 is connected to the second terminal of resistor R1; the first terminal of resistor R3 is connected to the second terminal of resistor R4, and the second terminal of resistor R4 is connected to the output terminal of operational amplifier U3.

[0084] Figure 6 In the circuit, operational amplifier U1, current-sampling resistor RI, and resistor R3 constitute a classic current-sampling circuit. The output signal current flowing through the current-sampling resistor RI generates a voltage drop across it. This voltage drop is detected by operational amplifier U1 and converted into an output voltage (i.e., the first low-frequency voltage signal). Simultaneously, the circuit design ensures that the values ​​of resistors R1, R2, R3, and R4 satisfy R1=R4 and R2=R3, thus constructing a balanced differential input structure for operational amplifier U1. This effectively suppresses DC errors caused by the input bias current, significantly improving the accuracy and stability of current sampling.

[0085] In some embodiments, the AC coupling circuit 102 includes a high-pass filter network; wherein the high-pass filter network is a capacitor, an RC high-pass filter, or an active filter circuit with high-pass characteristics.

[0086] A high-pass filter network acts as a "frequency filter," allowing high-frequency signals to pass through almost unimpeded while completely blocking DC and low-frequency components. The implementation of a high-pass filter network is flexible; it can be a simple DC-blocking capacitor forming a basic first-order high-pass filter; it can be an RC high-pass filter composed of resistors and capacitors, providing more precise cutoff frequency control; or it can employ an active filter circuit with high-pass characteristics (e.g., using an operational amplifier).

[0087] Figure 7 This is a schematic diagram of the structure of an AC coupling circuit provided in one embodiment of this application. Figure 7 As shown, the high-pass filter network in the AC coupling circuit 102 provided in this embodiment directly uses a DC blocking capacitor, namely the first capacitor C1. This design utilizes the inherent characteristic of capacitors to "block DC and pass AC," and can use only a single passive component to highly efficiently block the DC bias voltage and extremely low-frequency components from the previous stage, thereby eliminating inter-stage DC potential conflicts. At the same time, it can ensure that mid-to-high frequency signals pass through in a near-lossless manner. This solution is not only low in cost and compact in structure, but also has extremely high reliability.

[0088] Figure 8 This is a circuit diagram of a low-frequency amplifier circuit provided in one embodiment of this application. Figure 8 As shown, the low-frequency amplifier circuit 103 provided in this embodiment includes resistors R5, R6, R7, and R16, a DC voltage source, an operational amplifier U2, and resistor R8.

[0089] Specifically, the first end of resistor R5 is connected to the second input terminal of the low-frequency I / V circuit; the first end of resistor R6 is used to receive the input signal, and the second end of resistor R6 is connected to the second end of resistor R5; the first end of resistor R7 is used to receive the reference voltage, and the second end of resistor R7 is connected to the second end of resistor R6; the DC voltage source is used to generate the second reference voltage (in some embodiments, it can be set as the gate voltage of each field-effect transistor in several stages of power amplification units in the distributed broadband power amplifier module 20), and the negative terminal of the DC voltage source is connected to the ground terminal; the first end of resistor R16 is connected to the positive terminal of the DC voltage source, and the second end of resistor R16 is connected to the second end of resistor R7; the inverting input terminal of operational amplifier U2 is connected to the second end of resistor R6, the non-inverting input terminal of operational amplifier U2 is connected to the ground terminal, and the output terminal of operational amplifier U2 is used to output the second low-frequency signal; resistor R8 is connected across the output terminal and the inverting input terminal of operational amplifier U2.

[0090] In this embodiment, the low-frequency amplifier circuit 103 is essentially a summing amplifier circuit based on an operational amplifier. Its core function is to superimpose and amplify two input signals with an adjustable DC bias. Specifically, resistors R5 and R6 serve as channels for the two input signals, guiding the first low-frequency voltage signal from the low-frequency I / V circuit 101 and the original input signal from the previous stage to the inverting input node of the operational amplifier U2 for summation. Resistors R7 and R16 jointly introduce the reference voltage output by the reference module 30 and the second reference voltage generated by the DC voltage source, i.e., an adjustable DC component. The bias provided by this voltage source works together with the reference potential at the ground terminal. Finally, the operational amplifier U2, resistor R8, and the input resistor network constitute an inverting amplifier structure. Resistor R8, as a feedback resistor, determines the overall amplification factor, thereby accurately amplifying the summed signal and generating a second low-frequency voltage signal that combines amplified low-frequency information with a new DC operating point, which is then sent out from its output terminal.

[0091] Figure 9 This is a circuit diagram of a low-frequency superposition circuit provided in one embodiment of this application. Figure 9 As shown, the low-frequency superposition circuit 104 provided in this embodiment includes resistor R9, resistor R10, operational amplifier U3, resistor R11, and at least one set of low-frequency compensation networks.

[0092] Specifically, the first terminal of resistor R9 is used to receive the second low-frequency voltage signal; the first terminal of resistor R10 is connected to the second terminal of resistor R9; the non-inverting input terminal of operational amplifier U3 is connected to the ground terminal, and the inverting input terminal of operational amplifier U3 is connected to the second terminal of resistor R9; the first terminal of resistor R11 is connected to the output terminal of operational amplifier U3, and the second terminal of resistor R11 is connected to the second terminal of resistor R10, for outputting the amplified second low-frequency voltage signal;

[0093] The low-frequency compensation network is used to compensate for low-frequency distortion in the second low-frequency voltage signal.

[0094] Understandably, the low-frequency superposition circuit 104 guides the second low-frequency voltage signal from the low-frequency amplifier circuit 103 to the connection node between resistors R9 and R10 via resistor R9, which is connected to the output terminal of the AC coupling circuit 102. The operational amplifier U3 forms a negative feedback loop through the first resistor R11, which continuously monitors the potential of this node and compares it with the ground potential of the non-inverting input terminal. Once the node potential deviates from the ground potential due to signal superposition, the operational amplifier U3 will immediately output a correction current through resistor R11, thereby forcing the DC and low-frequency potential of this node to stabilize near zero volts. This design not only "injects" the second low-frequency voltage signal into the high-frequency path, completing the final superposition of the signal, but its included low-frequency compensation network (usually connected across the periphery of the operational amplifier U3, such as in the feedback loop) corrects the low-frequency phase or amplitude distortion that may occur during signal transmission, ensuring the integrity and fidelity of the synthesized broadband signal, especially the low-frequency part.

[0095] In some embodiments, the low-frequency compensation network includes a first low-frequency compensation network, a second low-frequency compensation network, and a third low-frequency compensation network.

[0096] Specifically, the first low-frequency compensation network includes a capacitor C4 and a resistor R15; the first terminal of the capacitor C4 is connected to the first terminal of the resistor R9; the first terminal of the resistor R15 is connected to the second terminal of the capacitor C4, and the second terminal of the resistor R15 is connected to the second terminal of the resistor R9.

[0097] The second low-frequency compensation network includes capacitor C3, resistor R13, and resistor R14; the first end of capacitor C3 is connected to the inverting input of operational amplifier U3; the first end of resistor R13 is connected to the second end of capacitor C3, and the second end of resistor R13 is connected to the output of operational amplifier U3; the first end of resistor R14 is connected to the second end of capacitor C3, and the second end of resistor R14 is connected to the ground terminal.

[0098] The third low-frequency compensation network includes capacitor C2 and resistor R12; the first end of resistor R12 is connected to the output of operational amplifier U3, and the second end of resistor R12 is connected to the first end of resistor R11; the first end of capacitor C2 is connected to the first end of resistor R11, and the second end of capacitor C2 is connected to ground.

[0099] In this embodiment, the low-frequency compensation network introduces frequency response adjustment into the signal path through multiple RC circuits to collaboratively complete low-frequency distortion compensation. The first low-frequency compensation network (C4 and R15) is connected in parallel across resistor R9, forming a frequency-varying negative feedback branch in parallel with the main signal path for high-frequency phase and amplitude compensation. The second low-frequency compensation network (C3, R13, and R14) is connected between the output and inverting input of operational amplifier U3 to correct the phase and amplitude response in the low-frequency band, thereby suppressing low-frequency distortion. The third low-frequency compensation network (C2 and R12) forms a low-pass filter between the output of operational amplifier U3 and feedback resistor R11, further optimizing the amplifier's stability and transient response. These three networks work together to ensure that the second low-frequency voltage signal is accurately superimposed onto the high-frequency path while its low-frequency components are reconstructed and preserved, thus achieving high-quality broadband signal synthesis at the system level.

[0100] Figure 10 This is a schematic diagram of a broadband power amplifier circuit provided in another embodiment of this application. Figure 10 As shown, the broadband power amplifier circuit provided in this embodiment, based on any of the above embodiments, also includes a constant current source module 40.

[0101] In this embodiment, the constant current source module 40 includes a power input terminal, a control terminal, and an output terminal. The constant current source module 40 is used to generate a constant current according to the external voltage received at the power input terminal, provide operating current to the distributed broadband power amplifier module 20 through its output terminal, and adjust the magnitude of the operating current according to the control signal received at the control terminal.

[0102] It can be understood that the constant current source module 40 is primarily responsible for providing a highly stable and precisely settable operating current to the distributed broadband power amplifier module 20. Through its internally integrated constant current generation and control circuitry, it dynamically and linearly adjusts the output current based on the external signal received at its control terminal. The design of the constant current source module 40 ensures that the operating point current of the entire amplifier is no longer significantly affected by power supply fluctuations or temperature drift, while also enabling functions such as gain control, power management, and adaptive bias.

[0103] Figure 11 This is a circuit diagram of a constant current source module provided in one embodiment of this application. Figure 11 As shown, the constant current source module 40 provided in this embodiment includes resistors R19, R20, R21, and R22, operational amplifier U4, resistors R23, R24, and R25, operational amplifier U5, capacitor C5, transistor QA, and inductor L1.

[0104] Specifically, the first terminal of resistor R19 is connected to the power input terminal; the first terminal of resistor R20 is connected to the first terminal of resistor R19; the first terminal of resistor R22 is connected to the ground terminal, and the second terminal of resistor R22 is connected to the second terminal of resistor R20; the first terminal of resistor R21 is connected to the second terminal of resistor R19; the non-inverting input terminal of operational amplifier U4 is connected to the second terminal of resistor R20, and the inverting input terminal of operational amplifier U4 is connected to the second terminal of resistor R21; the first terminal of resistor R23 is connected to the inverting input terminal of operational amplifier U4, and the second terminal of resistor R23 is connected to the output terminal of operational amplifier U4; the first terminal of resistor R24 ​​is connected to the second terminal of resistor R23. The second terminal of the capacitor is connected to the ground terminal; the first terminal of the resistor R25 is used to receive the control signal, and the second terminal of the resistor R25 is connected to the second terminal of the resistor R24; the non-inverting input terminal of the operational amplifier U5 is connected to the ground terminal, and the inverting input terminal of the operational amplifier U5 is connected to the second terminal of the resistor R25; the first terminal of the capacitor C5 is connected to the second terminal of the resistor R24, and the second terminal of the capacitor C5 is connected to the output terminal of the operational amplifier U5; the control terminal of the transistor QA is connected to the output terminal of the operational amplifier U5, and the first terminal of the transistor QA is connected to the second terminal of the resistor R19; the first terminal of the inductor L1 is connected to the second terminal of the transistor QA, and the second terminal of the inductor L1 is used to output the operating current.

[0105] Figure 12 A complete circuit diagram of a broadband power amplifier circuit provided in one embodiment of this application is shown. Figure 12 As shown, the broadband power amplifier circuit provided in this embodiment includes the circuits of each module / unit in the above embodiments. In order to realize the full-band power amplification of the input signal from DC to high-frequency components, as well as the flexible adjustment of DC bias, the design of the key resistors and capacitors in the broadband DC conversion module 10 must meet certain conditions. The values ​​of these resistors and capacitors directly determine the gain, frequency response and final signal synthesis accuracy of each module.

[0106] like Figure 12 As shown, assuming the DC bias of the output of the preamplifier a is Va_dc, the reference voltage output by the reference module 30 is Vref, and the second reference voltage generated by the voltage source is Vgc. The design of the broadband DC-DC converter module 10 in the broadband power amplifier circuit requires that the resistances R1, R4, R6, R10, and R11 be much greater than the impedance RS of device a and the resistance R18 in the distributed broadband power amplifier module 20, and that the sampling resistor RI be much smaller than the impedance RS of device a and the resistance R18 of the differential amplifier.

[0107] First, in the low-frequency I / V circuit 101, the value of the current-sampling resistor RI must be much smaller than the impedance RS of the preceding device and the resistance R18 of the subsequent load to minimize the insertion loss on the input signal path. The operational amplifier U1 and its external resistors form a balanced differential amplifier structure. The design must satisfy R1=R4 and R2=R3. At this point, the current I flowing through the current-sampling resistor RI is linearly converted into a voltage. The conversion formula is:

[0108] ;

[0109] Wherein, RI is the resistance value of the current sampling resistor RI, and R1~R4 are the resistance values ​​of resistors R1, R2, R3 and R4, respectively.

[0110] Furthermore, the low-frequency amplifier circuit 103 outputs to the low-frequency I / V circuit 101. Original input signal The reference voltage Vref and the second reference voltage Vgc are inverted and summed for amplification. The DC bias of the second low-frequency voltage signal output by the low-frequency amplifier circuit 103 is then applied. for:

[0111] ;

[0112] R5~R8 represent the resistance values ​​of resistors R5, R6, R7, R8, and R16, respectively.

[0113] Furthermore, the low-frequency superposition circuit 104 converts the second low-frequency voltage signal output by the low-frequency amplifier circuit 103 into a signal. The signal is then inverted and amplified, and then superimposed with the high-frequency signal after being DC-blocked by the AC coupling circuit 102. The final output signal has a DC bias. for:

[0114] ;

[0115] Furthermore, when the distributed broadband power amplifier module 20 is in normal operation, there needs to be a voltage difference Vg between the gate and source of the transistor in each power amplification unit.

[0116] Therefore, in circuit design, the resistance values ​​of resistors R7 and R8, R9 and R10, and R6 and R16 need to meet the following requirements:

[0117] R8=R7, R10=R9, R16=R6;

[0118] Meanwhile, in order to achieve accurate DC bias conversion and ensure that the DC bias output by the circuit matches the set DC bias, the following must also be satisfied:

[0119] ;

[0120] It is available now. .

[0121] In other words, at this time, the difference between the DC bias voltage output by the broadband DC conversion module 10 and the reference voltage Vref output by the reference module 30 is fixed at Vg, which is independent of the DC bias output by the preceding device a. This ensures that the DC bias output by device a will not affect the normal operation of the distributed broadband power amplifier module 20.

[0122] In the high-frequency path, the AC coupling circuit 102 (first capacitor C1, with a capacitance of C1) together with the impedance RS of the preceding device a, the current sampling resistor RI, and the resistor R18 in the distributed broadband power amplifier module 20 constitute a high-pass filter. Its cutoff frequency F is:

[0123] ;

[0124] Assuming the AC signal output by device a is Va_ac, when the frequency f of this AC signal is greater than the frequency F, the signal voltage Vb_rf received across resistor R18 in the distributed broadband power amplifier module 20 is...

[0125] ;

[0126] When the frequency f of the AC signal is less than the frequency F, the signal voltage Vb_lf received by resistor 18 in the distributed broadband power amplifier module 20 is:

[0127] ;

[0128] In circuit design, if ,but:

[0129] ;

[0130] Furthermore, if That can achieve This means that the input signal of the front-end device a is transmitted to the distributed broadband power amplifier module 20 without distortion for amplification.

[0131] At this time, the signal voltage Vb_lf received at the input terminal of the distributed broadband power amplifier module 20 is equal to Vb_rf, which means that the signal output by device a is transmitted to the input terminal.

[0132] Therefore, it is evident that in order to achieve the transmission of low-frequency signals, the circuit parameters must meet two core conditions:

[0133] 1. Impedance matching conditions:

[0134] R1=R4 and R2=R3;

[0135] ;

[0136] This condition ensures the matching of the low-frequency I / V sampling path with the source impedance.

[0137] 2. Gain matching condition:

[0138] ;

[0139] When the above conditions are met simultaneously, for low-frequency signals with frequencies lower than the cutoff frequency F, the output voltage across load R38 is... Will be related to high frequency output voltage Equal, that is:

[0140] .

[0141] By precisely selecting the ratios of resistors and the value of capacitor C1 during circuit design, full-band power amplification of input signals, from DC to high-frequency components, can be achieved. Furthermore, the global linkage of the reference module and the stable power supply of the constant current source module ensure extremely high stability and linearity of the amplifier's operating point. An independent bias adjustment terminal provides flexible adjustment capability for the output DC level. This fundamentally solves the technical bottleneck of traditional broadband power amplifiers, which cannot amplify DC and extremely low-frequency signals due to AC coupling design. It also significantly improves the adaptability of the output bias, the overall stability of the system, and the integration flexibility, meeting the growing demand for full-band, high-performance power amplification in modern communications, test and measurement, and other fields.

[0142] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art, under the guidance of this application, can make several simple deductions, modifications or substitutions based on the spirit of this application and the scope of protection of the claims without departing from the spirit of this application and the claims. All of these are within the protection scope of this application.

Claims

1. A broadband power amplifier circuit, characterized in that, include: A broadband DC-DC converter module includes an input terminal, a reference voltage input terminal, and an output terminal. The input terminal of the broadband DC-DC converter module is used to receive an input signal, and the reference voltage input terminal is used to receive a reference voltage. The broadband DC-DC conversion module is used to perform broadband DC-DC conversion on the received input signal according to the reference voltage, generate a DC bias intermediate signal based on the reference voltage and output it through its output terminal; A distributed broadband power amplifier module includes an input terminal, a bias adjustment terminal, an output terminal, and several power amplification units cascaded between the input terminal and the output terminal. The input terminal of the distributed broadband power amplifier module is used to receive the intermediate signal output by the broadband DC-DC converter module, and the bias adjustment terminal is used to receive a preset DC bias adjustment voltage. The distributed broadband power amplifier module is used to amplify the intermediate signal stage by stage through the several power amplification units under the drive of the intermediate signal, and adjust the DC bias of the amplified output signal according to the DC bias adjustment voltage.

2. The broadband power amplifier circuit according to claim 1, characterized in that, It also includes a reference module; the reference module has an input terminal and an output terminal, and the input terminal of the reference module is connected to the output terminal of the distributed broadband power amplifier module; The reference module is used to generate the reference voltage based on the voltage at the output of the distributed broadband power amplifier module, and simultaneously provide the reference voltage to the reference voltage input of the broadband DC-DC converter module and the common connection point of the source of each field-effect transistor in the power amplifier unit.

3. The broadband power amplifier circuit according to claim 2, characterized in that, The reference module includes an amplifier circuit; The amplifier circuit is used to sum and amplify the output voltage of the distributed broadband power amplifier module with the first reference voltage obtained from the outside, and output the reference voltage.

4. The broadband power amplifier circuit according to claim 3, characterized in that, The amplifier circuit includes resistors R26, R27, and R29, operational amplifier U6, resistor R28, and capacitor C6; The first end of resistor R26 is connected to the input terminal of the reference module; the first end of resistor R27 is used to receive the first reference voltage; the first end of resistor R29 is connected to the ground terminal, and the second end of resistor R29 is connected to the second end of resistor R26; the non-inverting input terminal of operational amplifier U6 is connected to the second end of resistor R26, the inverting input terminal of operational amplifier U6 is connected to the second end of resistor R27, and the output terminal of operational amplifier U6 is connected to the output terminal of the reference module; resistor R28 and capacitor C6 are connected in parallel and are connected across the inverting input terminal and the output terminal of operational amplifier U6.

5. The broadband power amplifier circuit according to claim 1, characterized in that, The broadband DC-DC converter module includes a low-frequency I / V circuit, an AC coupling circuit, a low-frequency amplifier circuit, and a low-frequency superposition circuit. The low-frequency I / V circuit is used to receive the input signal, sample the low-frequency current component in the input signal and convert it into a first low-frequency voltage signal; the AC coupling circuit is used to receive the input signal after current sampling by the low-frequency I / V circuit, and filter the DC and low-frequency components in the signal to output a high-frequency signal. The low-frequency amplifier circuit is used to receive the input signal and the first low-frequency voltage signal, and to sum and amplify the input signal and the first low-frequency voltage signal to generate a second low-frequency voltage signal. The low-frequency superposition circuit is used to receive the second low-frequency voltage signal, amplify the second low-frequency voltage signal and output it to the output terminal of the AC coupling circuit, and superimpose it with the high-frequency signal to generate the intermediate signal.

6. The broadband power amplifier circuit according to claim 5, characterized in that, The low-frequency I / V circuit includes a current sampling resistor RI, a resistor R1, a resistor R4, an operational amplifier U1, a resistor R2, and a resistor R3; The first end of the current sampling resistor R1 is used to receive the input signal, and the second end of the current sampling resistor R4 is used to output the current-sampled input signal; the first end of resistor R1 is connected to the first end of the current sampling resistor R1; the first end of resistor R4 is connected to the second end of the current sampling resistor R1; the non-inverting input of operational amplifier U1 is connected to the second end of resistor R1, the inverting input of operational amplifier U1 is connected to the second end of resistor R4, and the output of operational amplifier U1 is used to output the first low-frequency voltage signal; the first end of resistor R2 is connected to the ground terminal, and the second end of resistor R2 is connected to the second end of resistor R1; the first end of resistor R3 is connected to the second end of resistor R4, and the second end of resistor R4 is connected to the output of operational amplifier U3.

7. The broadband power amplifier circuit according to claim 5, characterized in that, The AC coupling circuit includes a high-pass filter network; wherein the high-pass filter network is a capacitor, an RC high-pass filter, or an active filter circuit with high-pass characteristics.

8. The broadband power amplifier circuit according to claim 6, characterized in that, The low-frequency amplifier circuit includes resistors R5, R6, and R7, a DC voltage source, resistor R16, operational amplifier U2, and resistor R8. The first end of resistor R5 is connected to the second input terminal of the low-frequency amplification module; the first end of resistor R6 is used to receive the input signal, and the second end of resistor R6 is connected to the second end of resistor R5; the first end of resistor R7 is used to receive the reference voltage, and the second end of resistor R7 is connected to the second end of resistor R6; the DC voltage source is used to generate a second reference voltage; the first end of resistor R16 is connected to the positive terminal of the DC voltage source to obtain the second reference voltage, and the second end of resistor R16 is connected to the second end of resistor R7; the inverting input terminal of operational amplifier U2 is connected to the second end of resistor R6, the non-inverting input terminal of operational amplifier U2 is connected to the ground terminal, and the output terminal of operational amplifier U2 is used to output the second low-frequency signal; resistor R8 is connected between the output terminal and the inverting input terminal of operational amplifier U2.

9. The broadband power amplifier circuit according to claim 8, characterized in that, The low-frequency superposition circuit includes resistor R9, resistor R10, operational amplifier U3, resistor R11, and at least one set of low-frequency compensation networks; The first terminal of resistor R9 is used to receive the second low-frequency voltage signal; the first terminal of resistor R10 is connected to the second terminal of resistor R9; the non-inverting input terminal of operational amplifier U3 is connected to the ground terminal, and the inverting input terminal of operational amplifier U3 is connected to the second terminal of resistor R9; the first terminal of resistor R11 is connected to the output terminal of operational amplifier U3, and the second terminal of resistor R11 is connected to the second terminal of resistor R10, for outputting the amplified second low-frequency voltage signal; The low-frequency compensation network is used to compensate for low-frequency distortion in the second low-frequency voltage signal.

10. The broadband power amplifier circuit according to claim 9, characterized in that, The low-frequency compensation network includes a first low-frequency compensation network, a second low-frequency compensation network, and a third low-frequency compensation network; The first low-frequency compensation network includes a capacitor C4 and a resistor R15; the first end of the capacitor C4 is connected to the first end of the resistor R9; the first end of the resistor R15 is connected to the second end of the capacitor C4, and the second end of the resistor R15 is connected to the second end of the resistor R9. The second low-frequency compensation network includes capacitor C3, resistor R13, and resistor R14; the first terminal of capacitor C3 is connected to the inverting input terminal of operational amplifier U3; the first terminal of resistor R13 is connected to the second terminal of capacitor C3, and the second terminal of resistor R13 is connected to the output terminal of operational amplifier U3; the first terminal of resistor R14 is connected to the second terminal of capacitor C3, and the second terminal of resistor R14 is connected to the ground terminal. The third low-frequency compensation network includes a capacitor C2 and a resistor R12; the first end of the resistor R12 is connected to the output terminal of the operational amplifier U3, and the second end of the resistor R12 is connected to the first end of the resistor R11; the first end of the capacitor C2 is connected to the first end of the resistor R11, and the second end of the capacitor C2 is connected to the ground terminal.

11. The broadband power amplifier circuit according to claim 1, characterized in that, It also includes a constant current source module; the constant current source module includes a power input terminal, a control terminal, and an output terminal; The constant current source module is used to generate a constant current based on the external voltage received at the power input terminal, provide operating current to the distributed broadband power amplifier module through its output terminal, and adjust the magnitude of the operating current according to the control signal received at the control terminal.

12. The broadband power amplifier circuit according to claim 11, characterized in that, The constant current source module includes resistors R19, R20, R21, and R22, operational amplifier U4, R23, R24, and R25, operational amplifier U5, capacitor C5, transistor QA, and inductor L1. The first end of resistor R19 is connected to the power input terminal; the first end of resistor R20 is connected to the first end of resistor R19; the first end of resistor R22 is connected to the ground terminal, and the second end of resistor R22 is connected to the second end of resistor R20; the first end of resistor R21 is connected to the second end of resistor R19; the non-inverting input terminal of operational amplifier U4 is connected to the second end of resistor R20, and the inverting input terminal of operational amplifier U4 is connected to the second end of resistor R21; the first end of resistor R23 is connected to the inverting input terminal of operational amplifier U4, and the second end of resistor R23 is connected to the output terminal of operational amplifier U4; the first end of resistor R24 ​​is connected to the second end of resistor R23. The connection is as follows: the first end of resistor R25 is used to receive the control signal, and the second end of resistor R25 is connected to the second end of resistor R24; the non-inverting input of operational amplifier U5 is connected to the ground terminal, and the inverting input of operational amplifier U5 is connected to the second end of resistor R25; the first end of capacitor C5 is connected to the second end of resistor R24, and the second end of capacitor C5 is connected to the output terminal of operational amplifier U5; the control terminal of transistor QA is connected to the output terminal of operational amplifier U5, and the first end of transistor QA is connected to the second end of resistor R19; the first end of inductor L1 is connected to the second end of transistor QA, and the second end of inductor L1 is used to output the operating current.

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