Power amplification circuit and electronic equipment
By dividing the transistors of the gallium nitride power device into multiple groups in parallel and introducing a matching network within the RLC output, the problem of insufficient power gain under self-excitation conditions is solved, and efficient power amplification and improvement of RF system performance is achieved.
Patent Information
- Application Number
- CN202421061865.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-15
- Publication Date
- 2025-02-07
- Estimated Expiration
- 2034-05-15
AI Technical Summary
Under the condition of suppressing self-excitation, the prior art is difficult to maintain sufficient power gain in gallium nitride power devices and cannot meet the terminal specification requirements.
A power amplifier circuit is designed to divide the original transistors into at least two groups, each of which is introduced into the RLC output matching network, and connected in parallel to improve input impedance and reduce the input power dissipated on the stable resistor.
While suppressing self-excitation, the power gain of the power amplifier circuit is improved, the terminal specification requirements are met, and the overall performance of the RF system is improved.
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Figure CN222441671U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of radio frequency circuits, and in particular to power amplifier circuits and electronic equipment. Background Art
[0002] Usually, the LC topology is used as the input internal matching of GaN power devices. However, after the GaN power devices complete the input and output matching, self-excitation may occur at the high SWR frequency of the circulator. If a stabilizing resistor R is introduced before the LC input internal matching network, the stability factor of the circuit can be improved and the self-excitation phenomenon can be eliminated.
[0003] However, after the stabilizing resistor R is introduced, although the self-excitation of the circuit is eliminated, the power gain of the circuit becomes smaller and cannot meet the terminal specification requirements.
[0004] Therefore, how to achieve sufficient gain while suppressing self-excitation is a technical problem that needs to be solved. Utility Model Content
[0005] The purpose of the present application is to provide a power amplifier circuit and an electronic device, which have sufficient gain under the condition of suppressing self-excitation.
[0006] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions.
[0007] In a first aspect, an embodiment of the present application provides a power amplifier circuit, comprising a capacitor unit and at least two branch units; each of the branch units comprises a resistor and a transistor, and a gate of the transistor is connected to the resistor; the capacitor unit and an inductor in the circuit form an input matching network of the transistor; the capacitor unit is used to receive a first signal;
[0008] At least two of the branch units are connected in parallel, one connection point after the parallel connection is connected to the capacitor unit, and the other connection point after the parallel connection is used to output a second signal; the second signal is a signal after the first signal is amplified.
[0009] Compared with the prior art, this application has the following beneficial effects:
[0010] The power amplifier circuit provided in the embodiment of the present application divides the original transistor into at least two groups. Each group can introduce a completely identical RLC output internal matching network, and the groups are connected in parallel. Because the real part of the input impedance of a single group is improved compared to the two groups in parallel, the real part of the input impedance of a single group is doubled, and the input power dissipated on the resistor in the branch unit, that is, the stabilizing resistor R, is reduced, thereby alleviating the problem of reduced circuit power gain.
[0011] Optionally, each of the branch units includes a first matching member and a second matching member, and the first matching member and the second matching member both have inductance, and form an input matching network of the transistor together with the capacitor unit and other inductances in the circuit;
[0012] The gate of the transistor of each branch unit is connected to the first end of the resistor through the first matching member, and the second end of the resistor is connected to the capacitor unit through the second matching member. The first matching member and the second matching member can play the dual role of introducing inductance and connecting devices.
[0013] Optionally, the first matching member includes a first metal wire; the second matching member includes a second metal wire;
[0014] The first metal line and the second metal line both have inductance, and form an input matching network of the transistor together with the capacitor unit and other inductances in the circuit;
[0015] The gate of the transistor of each branch unit is connected to the first end of the resistor through the first metal line, and the second end of the resistor is connected to the capacitor unit through the second metal line.
[0016] The first matching member and the second matching member are implemented with metal wires, which is easy to implement and has controllable costs.
[0017] Optionally, in each branch unit, there are at least two first metal wires, or at least two second metal wires, thereby the number of metal wires can be flexibly adjusted to achieve a required inductance.
[0018] Optionally, the capacitor unit includes a metal ground plane and a first metal plane, the metal ground plane and the first metal plane form a first capacitor, and the first metal plane is connected to the resistor through the second matching member. Using a metal plane as a capacitor in the capacitor unit is easy to manufacture and easy to connect between devices, and the cost is controllable.
[0019] Optionally, the capacitor unit further includes a second metal plane and a third matching piece; the third matching piece has an inductance, and forms an input matching network of the transistor with the capacitor unit and other inductors in the circuit;
[0020] The metal ground plane and the second metal plane form a second capacitor; the second metal plane is connected to the first metal plane through the third matching member. Thus, multiple capacitors can be formed in the capacitor unit, and inductance can also be set to achieve the required matching effect.
[0021] Optionally, the power amplifier circuit further includes an input metal wire, an output metal wire, an input pin and an output pin, wherein the input pin is connected to the capacitor unit through the input metal wire, and the output pin is connected to the branch unit through the output metal wire;
[0022] The input metal wire and the output metal wire both have inductance, and form an input matching network of the transistor with the capacitor unit and other inductances in the circuit. Connecting devices and pins through metal wires is easy to implement and cost-controllable.
[0023] Optionally, there are multiple input metal wires, or there are multiple output metal wires. The required matching effect can be achieved by setting the number of metal wires of the input pins and the output pins, thereby improving the flexibility of the design.
[0024] Optionally, the number of the branch units is 2, and the two branch units are arranged axially symmetrically. The symmetrical arrangement can ensure that the voltage and current characteristics of the corresponding points of the two branches are consistent, and is easy to design, and has stable and controllable performance.
[0025] In a second aspect, an embodiment of the present application provides an electronic device, which includes the power amplifier circuit of the first aspect, and the optional implementation methods and beneficial effects are consistent with the above-mentioned power amplifier circuit. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0027] Figure 1 A schematic diagram of the relationship between the standing wave ratio and frequency of a circulator;
[0028] Figure 2 This is a schematic diagram of an LC input internal matching;
[0029] Figure 3 Schematic diagram of the self-excitation phenomenon of the device that completes impedance matching at the high standing wave ratio frequency of the circulator;
[0030] Figure 4 A schematic diagram of the relationship between the stability factor and the frequency of a power amplifier circuit that has been matched;
[0031] Figure 5 This is the schematic diagram of the RLC input internal matching circuit;
[0032] Figure 6A schematic diagram of a power amplifier circuit with RLC input internal matching provided in an embodiment of the present application;
[0033] Figure 7 A schematic diagram of a power amplifier circuit with a matching component arranged in a branch provided in an embodiment of the present application;
[0034] Figure 8 A schematic diagram of a power amplifier circuit packaging structure provided in an embodiment of the present application;
[0035] Fig. 9 for Figure 8 Schematic diagram corresponding to the package shown.
[0036] Description of reference numerals:
[0037] 101 Input pin
[0038] 102 Input Metal Wire
[0039] 103 Metal Ground Plane
[0040] 104 Second Metal Plane
[0041] 105 Third matching piece
[0042] 106 First Metal Plane
[0043] 107 Second Metal Wire
[0044] 108 Resistor Package
[0045] 109 First Metal Wire
[0046] 110 Transistor Package
[0047] 111 Output metal wire
[0048] 112 Output pins DETAILED DESCRIPTION
[0049] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. The described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described in the drawings here can be arranged and designed in various different configurations.
[0050] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.
[0051] In the description of this application, it should be noted that relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium.
[0052] The following is an example of a practical engineering problem to introduce the application of this solution.
[0053] A certain electronic device has a demand for a gallium nitride high-efficiency power amplifier. A circulator needs to be connected between the amplifier output and a variable load to improve the terminal mismatch.
[0054] In the actual debugging process, it is found that Figure 1 , the circulator's operating frequency range is 2.4GHz to 2.5GHz, and the standing wave is ≤1.3, while at non-operating frequencies, the standing wave rapidly deteriorates to ≥20 at some frequencies, such as Figure 1 This causes serious mismatch of the GaN power amplifier at high VSWR frequencies and deteriorates device stability.
[0055] like Figure 2 Next, the input internal matching of the GaN power device T1 is completed using a common LC topology structure, which includes a capacitor C1 and an inductor L1.
[0056] After the device completes input and output matching, self-excitation may occur at the high SWR frequency of the circulator, such as Figure 3 The instability of the system can be seen by looking at the stability factor Mu of the power amplifier circuit, such as Figure 4 , the stability factor Mu ≥ 1 indicates that the system is absolutely stable, and the 3.0GHz Mu corresponding to m4 is -1.054. It can be seen that the stability factor Mu of the circuit at the high standing wave ratio frequency of the circulator is less than 0 (the high standing wave ratio of the circulator does not necessarily lead to self-excitation of the circuit, but only reduces the impedance stability area of the circuit).
[0057] If a stabilizing resistor R is introduced before the LC input matching network, Figure 5, the stability factor of the circuit can be improved and the self-excitation phenomenon can be eliminated.
[0058] However, after the stabilizing resistor R is introduced, although the self-excitation of the circuit is eliminated, the power gain of the circuit becomes smaller, for example, only about 15dB, while the required power gain is ≥18dB. The gain is too small to meet the terminal specification requirements.
[0059] In response to the above RF engineering problems, the following solution is proposed. This solution maintains an 18dB power gain while eliminating circuit self-excitation, and the performance indicators of the entire RF system meet the terminal requirements.
[0060] See also Figure 6 An embodiment of the present application provides a power amplifier circuit, including a capacitor unit C2 and at least two branch units, and the at least two branch units are connected in parallel.
[0061] Figure 6 An implementation of two branch units is shown, the first branch unit includes a resistor R11 and a transistor T11, and the second branch unit includes a resistor R12 and a transistor T12. The gate of the transistor of each branch unit is connected to a resistor. The two branch units are connected in parallel. The resistors in the branch units play a role in suppressing the self-excitation of the circuit and improving the stability of the circuit. The transistor can be a gallium nitride high electron mobility transistor (HEMT).
[0062] The power amplifier circuit has an inductor, which may be formed by a conductor connecting components. The capacitor unit C2 and the inductor in the circuit form an input matching network of the transistor.
[0063] The first end of the capacitor unit C2 is used to receive the first signal; one connection point of the branch units after parallel connection is connected to the second end of the capacitor unit C2, and the other connection point after parallel connection is used to output the second signal, which is the signal after the first signal is gained.
[0064] This solution divides the original transistor into at least two groups, for example, the original 20W single GaN HEMT is divided into 2 groups, each group has a 10W GaN HEMT. Each group can introduce the same RLC output internal matching network, and the groups are connected in parallel. Because the real part of the input impedance of a single group is improved compared to the two groups in parallel, the real part of the input impedance of a single group is doubled, and the input power dissipated on the resistor in the branch unit, that is, the stabilizing resistor R, is reduced, alleviating the problem of reduced circuit power gain.
[0065] like Figure 7, the first branch unit may include a matching piece L11 and a matching piece L21, the second branch unit may include a matching piece L12 and a matching piece L22, the gate of the transistor T11 is connected to the first end of the resistor R11 through the matching piece L11, and the second end of the resistor R11 is connected to the capacitor unit C2 through the matching piece L21. The gate of the transistor T12 is connected to the first end of the resistor R12 through the matching piece L21, and the second end of the resistor R12 is connected to the capacitor unit C2 through the matching piece L22.
[0066] Matching components L11, L21, L12 and L22 all have inductance, and can form an input matching network of the transistor with capacitor unit C2 and other inductors in the circuit. The first matching component and the second matching component can play the dual role of introducing inductance and connecting devices.
[0067] Figure 8 The structure of a power tube device is shown. Fig. 9 The circuit schematic is shown. The matching parts can be realized by metal wires. Figure 8 Parts in Fig. 9 The devices in the table correspond to the following:
[0068] The transistor package 110 includes a transistor T11 and a transistor T12;
[0069] The output metal wire 111 corresponds to the inductor L34;
[0070] The output pin 112 corresponds to the output port OUT;
[0071] The first metal line 109 corresponds to the inductor L11 and the inductor L12;
[0072] The resistor package 108 includes a resistor R11 and a resistor R12;
[0073] The second metal wire 107 corresponds to the inductor L33;
[0074] The capacitor unit includes a metal ground plane 103 and a first metal plane 106, and the metal ground plane 103 and the first metal plane 106 form a first capacitor C21;
[0075] The capacitor unit may further include a second metal plane 104 and a third matching member 105; the third matching member 105 corresponds to the inductor L32 and may be a metal wire or multiple metal wires; the metal ground plane 103 and the second metal plane 104 form a second capacitor C22;
[0076] The input metal wire 102 corresponds to the inductor L31;
[0077] The input pin 101 corresponds to the input port IN.
[0078] The capacitor unit is connected to the input pin 101 through an input metal line 102 .
[0079] like Figure 8 One end of a transistor is connected to an output pin 112 through four output metal wires 111, and the other end is connected to a first end of a resistor package 108 through three first metal wires 109. The other end of the resistor package 108 is connected to a first metal plane 106 of a capacitor unit through a second metal wire 107. The first metal plane 106 is connected to a second metal plane 104 through four metal wires. An input pin 101 is connected to the second metal plane 104 through three input metal wires 102.
[0080] The number of metal wires at each location can be set according to the inductance required in the circuit. If a larger inductance is required, the number of metal wires can be increased. The metal wires not only play a connecting role, but also increase the flexibility of inductance adjustment. They are easy to implement and cost-controlled.
[0081] Using a metal plane as a capacitor in a capacitor unit is easy to manufacture and easy to connect between devices, and the cost is controllable.
[0082] like Figure 8 The structure of the entire circuit can be arranged axially symmetrically. The symmetrical arrangement can ensure that the voltage and current characteristics of the corresponding points of the two branches are consistent. It is also easy to design, and the performance is stable and controllable.
[0083] Based on the above embodiments, the embodiments of the present application further provide an electronic device, the electronic device includes the above power amplifier circuit, and the optional implementation methods and beneficial effects are consistent with the above power amplifier circuit.
[0084] In general, the present application proposes a power amplifier circuit and an electronic device, which relate to the field of radio frequency circuit technology. The power amplifier circuit includes a capacitor unit and at least two branch units. Each branch unit includes a resistor and a transistor, and the gate of the transistor is connected to the resistor. The capacitor unit and the inductor in the circuit form an input matching network of the transistor. The capacitor unit is used to receive a first signal. At least two branch units are connected in parallel, one connection point after the parallel connection is connected to the capacitor unit, and the other connection point after the parallel connection is used to output a second signal. The second signal is a signal after the first signal is gained. The power amplifier circuit improves the power gain under the condition of suppressing self-excitation.
[0085] The above-described device and system embodiments are merely illustrative, and some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. A person skilled in the art may understand and implement the present embodiment without creative effort.
[0086] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.
Claims
1. A power amplifier circuit, characterized in that: The circuit comprises a capacitor unit and at least two branch units; each of the branch units comprises a resistor and a transistor, and the gate of the transistor is connected to the resistor; the capacitor unit and the inductor in the circuit form an input matching network of the transistor; the capacitor unit is used to receive a first signal; At least two of the branch units are connected in parallel, one connection point after the parallel connection is connected to the capacitor unit, and the other connection point after the parallel connection is used to output a second signal; the second signal is a signal after the first signal is amplified.
2. The power amplifier circuit according to claim 1, characterized in that: Each of the branch units includes a first matching member and a second matching member, wherein the first matching member and the second matching member both have inductance, and form an input matching network of the transistor together with the capacitor unit and other inductances in the circuit; The gate of the transistor of each branch unit is connected to the first end of the resistor through the first matching component, and the second end of the resistor is connected to the capacitor unit through the second matching component.
3. The power amplifier circuit according to claim 2, characterized in that: The first matching member includes a first metal wire; the second matching member includes a second metal wire; The first metal line and the second metal line both have inductance, and form an input matching network of the transistor together with the capacitor unit and other inductances in the circuit; The gate of the transistor of each branch unit is connected to the first end of the resistor through the first metal line, and the second end of the resistor is connected to the capacitor unit through the second metal line.
4. The power amplifier circuit according to claim 3, characterized in that: In each of the branch units, there are at least two first metal wires, or there are at least two second metal wires.
5. The power amplifier circuit according to claim 2, characterized in that: The capacitor unit includes a metal ground plane and a first metal plane, the metal ground plane and the first metal plane form a first capacitor, and the first metal plane is connected to the resistor through the second matching member.
6. The power amplifier circuit according to claim 5, characterized in that: The capacitor unit further includes a second metal plane and a third matching piece; the third matching piece has an inductance, and forms an input matching network of the transistor with the capacitor unit and other inductors in the circuit; The metal ground plane and the second metal plane form a second capacitor; the second metal plane is connected to the first metal plane through the third matching component.
7. The power amplifier circuit according to claim 1, characterized in that: The power amplifier circuit further includes an input metal line, an output metal line, an input pin and an output pin, wherein the input pin is connected to the capacitor unit through the input metal line, and the output pin is connected to the branch unit through the output metal line; The input metal line and the output metal line both have inductance, and together with the capacitor unit and other inductances in the circuit form an input matching network of the transistor.
8. The power amplifier circuit according to claim 7, characterized in that: There are multiple input metal lines, or there are multiple output metal lines.
9. The power amplifier circuit according to claim 1, characterized in that: The number of the branch units is 2, and the two branch units are arranged in an axisymmetric manner.
10. An electronic device, characterized in that: The electronic device comprises the power amplifier circuit according to any one of claims 1 to 9.