Power amplifier standing wave protection circuit based on temperature detection and control method

Abstract

The invention discloses a power amplifier standing wave protection circuit based on temperature detection and a control method, which are applied to a solid-state high-power component and comprise a preceding-stage driving amplification link, a final-stage power amplification circuit, a temperature detection circuit, a control protection circuit and a power supply circuit, the temperature detection circuit transmits a temperature detection signal of a power device in the power amplifier assembly, the control protection circuit outputs a grid control signal to the power supply circuit and outputs an alarm signal according to the temperature detection signal, the power supply circuit is connected with the control protection circuit, and a selective switch is arranged in the power supply circuit. The gate voltage is switched through the selection switch to control the on or off of the amplifiers in the preceding-stage driving amplification link and the final-stage power amplification circuit, so that the power device can be effectively prevented from being burnt in a large standing wave scene, and the method is suitable for low-frequency, broadband, small-size and other application scenes in which standing wave protection is difficult to realize by isolators.

Description

Technical Field

[0001] The present invention relates to the technical field of standing wave protection of high-power products, and in particular to a standing wave protection circuit and a control method for a power amplifier based on temperature detection. Background Art

[0002] In recent years, with the increase in the output power of power amplifier components in radar-electronic systems and the increase in the number of power amplifier arrays, power amplifier burnout failures caused by long-term operation under high-power conditions have occurred frequently. Excessive standing waves are one of the important reasons for damaging high-power microwave devices, among which the power devices at the end of high-power components are most sensitive to standing wave deterioration. In the case of excessive standing waves or total reflection, power devices may be damaged and standing wave failure may occur. According to the analysis of the causes of the failures, a considerable number of power amplifier burnouts are due to the lack of standing wave protection circuits. When standing wave abnormalities occur, the power amplifiers cannot be shut down in time, resulting in burnouts. Due to the characteristics of some power amplifiers such as wide operating frequency bands and insufficient circuit size space, it is difficult to use isolators (or circulators), directional couplers, etc. for standing wave detection and protection.

[0003] The standing wave protection measures for power amplifiers in related technologies include: standing wave protection circuits based on isolators and circulators and standing wave protection forms based on directional couplers plus detection units. However, there are problems such as active standing wave failure in power amplifier array applications, and traditional standing wave protection circuits have large size, narrow operating frequency band, high detection accuracy requirements, and introduced circuit losses. Summary of the invention

[0004] In view of the above problems, the present invention provides a power amplifier standing wave protection circuit and control method based on temperature detection to solve the technical problem that the standing wave protection circuit is limited by detection accuracy and operating frequency band.

[0005] In a first aspect, the present invention provides a power amplifier standing wave protection circuit based on temperature detection, which is applied to a solid-state high-power component, including: a pre-stage drive amplifier link, a final stage power amplifier circuit, a temperature detection circuit, a control protection circuit and a power supply circuit, wherein:

[0006] The output end of the temperature detection circuit is connected to the input end of the control protection circuit, and is used to transmit the temperature detection signal of the power device in the power amplifier component;

[0007] The two output terminals of the control protection circuit respectively output a gate control signal to the power supply circuit and an alarm signal according to the temperature detection signal;

[0008] The input end of the power supply circuit is connected to the output end of the control protection circuit, and the output end of the power supply circuit is connected to a selection switch, and the selection switch is respectively connected to the front-stage driving amplifier link and the final-stage power amplifier circuit, and the gate control signal controls the power supply circuit to output a gate voltage, and the selection switch controls the amplifier in the front-stage driving amplifier link and the final-stage power amplifier circuit to turn on or off according to the gate voltage.

[0009] In one embodiment, the temperature detection circuit includes a temperature sensor, and the temperature sensor is disposed on a heat sink of a die in the power device.

[0010] In one embodiment, the control protection circuit includes: a comparator, a first input terminal of the comparator receives the temperature detection signal output by the temperature sensor, and a second input terminal of the comparator is used to set a determination threshold voltage.

[0011] In one embodiment, the temperature sensor is sintered on the same heat sink as the die in the power device through a eutectic welding process, and the temperature sensor outputs an analog voltage signal to the control protection circuit.

[0012] In one embodiment, the pre-stage driving amplifier link includes a first amplifier and a second amplifier, the final stage power amplifier circuit includes a third amplifier, the first amplifier, the second amplifier and the third amplifier are connected in sequence, and the selection switch connects the gates of the first amplifier, the second amplifier and the third amplifier.

[0013] In one embodiment, the first output terminal of the comparator is connected to a digital component for outputting an alarm signal, and the second output terminal of the comparator is connected to the power supply circuit.

[0014] In one embodiment, the first input terminal of the selection switch is connected to a low level, and the second input terminal of the selection switch is connected to the gate voltage.

[0015] In a second aspect, an embodiment of the present application provides an electronic device, including a power amplifier standing wave protection circuit based on temperature detection in the first aspect.

[0016] In a third aspect, an embodiment of the present application provides a control method, which is applied to the electronic device in the second aspect, including:

[0017] Obtaining a voltage value corresponding to the temperature detection signal;

[0018] Comparing the voltage value with a threshold voltage in the control protection circuit to determine whether the standing wave is abnormal;

[0019] When it is determined that the voltage value does not meet the discrimination threshold voltage, outputting a gate control signal to the power supply circuit and outputting the alarm signal;

[0020] The power supply circuit is controlled to turn on or off the gate voltage based on the gate control signal, so as to control the amplifiers in the pre-stage driving amplifier chain and the final-stage power amplifier circuit to turn on or off.

[0021] Compared with the prior art, one or more embodiments of the above scheme may have the following advantages or beneficial effects:

[0022] The present invention provides a power amplifier standing wave protection circuit based on temperature detection and a control method. The power amplifier standing wave protection circuit based on temperature detection is applied to a solid-state high-power component, comprising: a pre-stage driving amplifier link, a final-stage power amplifier circuit, a temperature detection circuit, a control protection circuit and a power supply circuit, wherein: the output end of the temperature detection circuit is connected to the input end of the control protection circuit, and is used to transmit a temperature detection signal of a power device in the power amplifier component; the two output ends of the control protection circuit respectively output a gate control signal to the power supply circuit and an output alarm signal according to the temperature detection signal; the input end of the power supply circuit is connected to the output end of the control protection circuit, and the output end of the power supply circuit is connected to a selection switch, and the selection switch is respectively connected to the pre-stage driving amplifier link and the final-stage power amplifier circuit, and the gate control signal controls the gate control signal to the power supply circuit and the .... The power supply circuit outputs a gate voltage, and the selection switch controls the opening or closing of the amplifier in the front-stage driving amplifier link and the final-stage power amplifier circuit through the gate voltage, which can effectively prevent the power device from burning out in a large standing wave scenario; the standing wave protection circuit of temperature detection is not limited by the working bandwidth and frequency, and because the RF link does not introduce other devices, there is no additional circuit loss; the temperature sensor is placed close to the die, which can better reflect whether the power device most affected by the standing wave is in a mismatched state, with small detection error and strong anti-interference ability; this circuit reduces the large-sized and high-cost devices such as isolators, directional couplers and detectors in traditional standing wave protection technology, and realizes small size and low cost of the circuit; it can be applied to low-frequency, broadband, small-sized and other application scenarios where isolators are difficult to achieve standing wave protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The scope of the present disclosure may be better understood by reading the following detailed description of exemplary embodiments in conjunction with the accompanying drawings. The drawings included are:

[0024] Figure 1 A circuit principle block diagram of a power amplifier standing wave protection circuit based on temperature detection provided by an embodiment of the present invention is shown;

[0025] Figure 2 A schematic diagram of an implementation method of a control protection circuit and a power supply circuit provided by an embodiment of the present invention is shown;

[0026] Figure 3 A flowchart of a power amplifier standing wave protection circuit based on temperature detection provided by an embodiment of the present invention is shown;

[0027] Figure 4 A schematic diagram of an overall test structure relationship provided by an embodiment of the present invention is shown;

[0028] Figure 5 A schematic flow chart of a control method provided by an embodiment of the present invention is shown;

[0029] Figure 6 A structural block diagram of an electronic device proposed in an embodiment of the present invention for executing a control method according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present invention. All other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0031] In the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0032] If similar descriptions of "first / second / third" appear in the application documents, the following description is added. In the following description, the terms "first / second / third" are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It is understandable that "first / second / third" can be interchanged in a specific order or sequence where permitted, so that the embodiments of the invention described herein can be implemented in an order other than that illustrated or described herein.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein are only for the purpose of describing the embodiments of the present invention and are not intended to limit the present invention.

[0034] In the related technology, the current standing wave protection measures for power amplifiers mainly include the following methods:

[0035] 1. The standing wave protection circuit based on isolators and circulators, the circuit principle of which is to add an isolator or circulator at the output end of the power amplifier so that all the reflected power is absorbed by the load, thereby achieving the purpose of protecting the power device. The applicant has found through research that there are some limitations in its actual engineering application: 1. The bandwidth of the circulator is limited, and when the working bandwidth spans an octave, almost no isolator is available; 2. The isolator and circulator will introduce certain losses in the RF link; 3. The circuit size of the added isolator and circulator is large, and when the operating frequency is low, the size is even larger, which makes it difficult to carry out when the component space is limited.

[0036] Second, the standing wave protection form based on directional coupler plus detection unit, adds a directional coupler to the power amplifier output circuit, extracts the reflected power signal in the circuit, and then performs detection and threshold comparison on the signal. When a large standing wave is detected in the power amplifier circuit, the power tube transmission link is closed to protect the power amplifier link. The applicant has found through research that the limitations of this circuit are: 1. The directivity and coupling flatness of the coupler are required to be high. Insufficient directivity and coupling flatness will lead to false protection; 2. The broadband coupler circuit is large in size, especially in low-frequency application scenarios; 3. The detection output level is different at different frequencies, and there is a problem with the frequency response of the detector; 4. The protection circuit requires detectors, directional couplers with high directivity and other devices, which are relatively expensive.

[0037] Based on the problems existing in the related technologies, the applicant faces the anti-burning design requirements of power amplifier products, and targets the active standing wave failure of power amplifiers in array applications, as well as the large size, narrow working frequency band, high detection accuracy, and circuit loss of traditional standing wave protection circuits. The purpose of the present invention is to solve the technical difficulties of standing wave protection circuits limited by detection accuracy and working frequency band, and combine the temperature characteristics under large standing wave scenarios to achieve broadband, low frequency, and small size application scenarios of standing wave protection circuits.

[0038] See also Figure 1 , Figure 1 A circuit principle block diagram of a power amplifier standing wave protection circuit based on temperature detection provided in an embodiment, a power amplifier standing wave protection circuit based on temperature detection, applied to a power amplifier component, including: a pre-stage drive amplifier link 1, a final stage power amplifier circuit 2, a temperature detection circuit 3, a control protection circuit 4 and a power supply circuit 5, wherein:

[0039] The output end of the temperature detection circuit 3 is connected to the input end of the control protection circuit 4, and is used to transmit the temperature detection signal V1 of the power device in the power amplifier component;

[0040] The two output terminals of the control protection circuit 4 respectively output a gate control signal V2 to the power supply circuit 5 and an output alarm signal V3 according to the temperature detection signal V1;

[0041] The input end of the power supply circuit 5 is connected to the output end of the control protection circuit 4, and the output end of the power supply circuit 5 is connected to a selection switch, which is respectively connected to the front-stage driving amplifier link 1 and the final-stage power amplifier circuit 2. The gate control signal V2 controls the power supply circuit 5 to output the gate voltage, and the selection switch controls the opening or closing of the amplifiers in the front-stage driving amplifier link 1 and the final-stage power amplifier circuit 2 through the gate voltage V4.

[0042] In this embodiment, the circuit reduces the large-sized and high-cost devices such as isolators, directional couplers and detectors in the traditional standing wave protection technology, thereby achieving small size and low cost of the circuit. In addition, the RF link in this embodiment does not introduce other devices, so there is no additional circuit loss. It can be applied to low-frequency, broadband, small-size and other application scenarios where isolators are difficult to achieve standing wave protection.

[0043] In some embodiments, the pre-stage driving amplifier link 1 includes a first amplifier and a second amplifier, the final stage power amplifier circuit 2 includes a third amplifier, the first amplifier, the second amplifier and the third amplifier are connected in sequence, and the selection switch connects the gates of the first amplifier, the second amplifier and the third amplifier.

[0044] In this embodiment, the amplifiers in the mid-pre-stage driving amplifier link 1 and the final-stage power amplifier circuit 2 are turned off in a gate control manner to effectively prevent the power devices from burning out in a large standing wave scenario.

[0045] In some embodiments, the temperature detection circuit 3 includes a temperature sensor, and the temperature sensor is disposed on a heat sink of a die in the power device.

[0046] In some embodiments, the temperature sensor is sintered on the same heat sink as the die in the power device through a eutectic welding process, and the temperature sensor outputs an analog voltage signal to the control protection circuit.

[0047] In this embodiment, the temperature sensor is placed close to the die, which can better reflect whether the power device most affected by the standing wave is in a mismatch state, with small detection error and strong anti-interference ability.

[0048] See also Figure 2 , Figure 2 A schematic diagram of an implementation method of a control protection circuit and a power supply circuit provided in an embodiment.

[0049] In some embodiments, the control protection circuit 4 includes: a comparator, a first input terminal of the comparator receives a temperature detection signal V1 output by a temperature sensor, and a second input terminal of the comparator is used to set a determination threshold voltage.

[0050] In some embodiments, a first output terminal of the comparator is connected to a digital component for outputting an alarm signal, and a second output terminal of the comparator is connected to a power supply circuit.

[0051] In some embodiments, the first input terminal of the selection switch is connected to a low level, and the second input terminal of the selection switch is connected to a gate.

[0052] Among them, the selection switch uses a two-to-one switch, the two-to-one switch input end of the control protection circuit 4 is respectively connected to the -5V low level and the gate voltage output by the voltage conversion, the control end is connected to the gate control signal V2, and the output end is connected to the gate of the amplifier.

[0053] In the above embodiment, the control protection circuit 4 outputs the gate control signal V2 to the power circuit 5 by comparing the received temperature detection signal V1 with the size of the judgment threshold, and outputs the alarm signal V3 to the upper digital component in case of abnormality.

[0054] See also Figure 3 , Figure 3 This is a working flow chart of a power amplifier standing wave protection circuit based on temperature detection provided in this embodiment, which includes S201 to S207.

[0055] S201: Open the RF channel and input the RF signal.

[0056] Among them, see Figure 4 A schematic diagram of an overall test structure relationship is shown, in which a standing wave phase adjuster adjusts the standing wave and phase of the corresponding power load.

[0057] S202: Compare the temperature detection signal output by the temperature sensor with the determination threshold voltage.

[0058] The temperature sensor outputs an analog voltage signal to the control protection circuit, and the comparator in the control circuit compares the voltage corresponding to the temperature detection signal with the set judgment threshold voltage.

[0059] S203: Determine whether the standing wave is abnormal.

[0060] Among them, for the power devices in the power amplifier components of the same product, there is a corresponding relationship between the standing wave and the temperature, and the above comparison is used to determine whether the standing wave is abnormal.

[0061] S204: reporting an alarm signal and outputting a gate control signal to a power circuit.

[0062] Among them, in abnormal situations, an early warning is output to the digital component to provide a digital early warning notification prompt, and a gate control signal is output for protection to prevent the power device from burning out in a large standing wave scenario.

[0063] S205: Switch the two-choice switch to turn off the power amplifier grid voltage.

[0064] S206: Externally eliminate fault information and restart the power after confirming that everything is correct.

[0065] S207: Normal operation.

[0066] See also Figure 5 , Figure 5 A control method flow chart provided in an embodiment of the present invention is applied to an electronic device including a power amplifier standing wave protection circuit based on temperature detection. The control method includes S110 to S140.

[0067] S110: Obtaining a voltage value corresponding to the temperature detection signal.

[0068] S120: Compare the voltage value with the discrimination threshold voltage in the control protection circuit to determine whether the standing wave is abnormal.

[0069] S130: When it is determined that the voltage value exceeds the judgment threshold voltage, a gate control signal is output to the power supply circuit, and an alarm signal is output.

[0070] S140: Controlling the power supply circuit to turn on or off the gate voltage based on the gate control signal to control the amplifier in the front-stage driving amplifier link and the final-stage power amplifier circuit to turn on or off.

[0071] The control method provided in the embodiment of the present application can be applied to an electronic device composed of a power amplifier standing wave protection circuit based on temperature detection in the present application, which can effectively monitor the power devices in the power amplifier component and perform standing wave protection.

[0072] This application uses a power amplifier component with an output power greater than 50W at 1-4GHz. Figure 1 Design the circuit structure shown and Figure 4 In the overall test structure relationship diagram shown, the test is carried out to test the working state, temperature rise and standing wave protection function of the power amplifier component under different standing wave and phase conditions. The standing wave phase adjuster adjusts the standing wave size and phase at the output end of the power amplifier, and the thermal imager checks the temperature of the component under thermal equilibrium. When the standing wave is less than 3:1, the product is not protected; when the standing wave is greater than 10:1, the product is protected; after the standing wave is reduced, the power is turned on again, and the product resumes normal operation, which better achieves the effect required by this application.

[0073] See also Figure 6 , Figure 6 The present invention provides a structural block diagram of an electronic device 200 that can execute the above control method. The electronic device may include a power amplifier standing wave protection circuit based on temperature detection in the embodiment of the present invention.

[0074] The electronic device 200 further includes a processor 202 and a memory 204. The memory 204 stores a program that can execute the contents of the aforementioned embodiments, and the processor 202 can execute the program stored in the memory 204, wherein the program can include the process of the control method of the present application.

[0075] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

[0076] Although the embodiments disclosed in the present invention are as above, the contents are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A power amplifier standing wave protection circuit based on temperature detection, applied to solid-state high-power components, characterized in that: include: Pre-stage drive amplifier link, final stage power amplifier circuit, temperature detection circuit, control protection circuit and power supply circuit, wherein: The output end of the temperature detection circuit is connected to the input end of the control protection circuit, and is used to transmit the temperature detection signal of the power device in the power amplifier component; The two output terminals of the control protection circuit respectively output a gate control signal to the power supply circuit and an alarm signal according to the temperature detection signal; The input end of the power supply circuit is connected to the output end of the control protection circuit, and the output end of the power supply circuit is connected to a selection switch, and the selection switch is respectively connected to the front-stage driving amplifier link and the final-stage power amplifier circuit, and the gate control signal controls the power supply circuit to output a gate voltage, and the selection switch controls the amplifier in the front-stage driving amplifier link and the final-stage power amplifier circuit to turn on or off according to the gate voltage.

2. A power amplifier standing wave protection circuit based on temperature detection according to claim 1, characterized in that: The temperature detection circuit includes a temperature sensor, and the temperature sensor is arranged on a heat sink of a die in the power device.

3. A power amplifier standing wave protection circuit based on temperature detection according to claim 2, characterized in that: The control protection circuit comprises: a comparator, a first input terminal of the comparator receives a temperature detection signal output by the temperature sensor, and a second input terminal of the comparator is used to set a determination threshold voltage.

4. A power amplifier standing wave protection circuit based on temperature detection according to claim 2, characterized in that: The temperature sensor is sintered on the same heat sink as the tube core in the power device through a eutectic welding process, and the temperature sensor outputs an analog voltage signal to the control protection circuit.

5. The power amplifier standing wave protection circuit based on temperature detection according to claim 1, characterized in that: The pre-stage driving amplifier link includes a first amplifier and a second amplifier, the final stage power amplifier circuit includes a third amplifier, the first amplifier, the second amplifier and the third amplifier are connected in sequence, and the selection switch connects the gates of the first amplifier, the second amplifier and the third amplifier.

6. A power amplifier standing wave protection circuit based on temperature detection according to claim 3, characterized in that: The first output end of the comparator is connected to a digital component for outputting an alarm signal, and the second output end of the comparator is connected to the power supply circuit.

7. A power amplifier standing wave protection circuit based on temperature detection according to claim 5, characterized in that: The first input terminal of the selection switch is connected to a low level, and the second input terminal of the selection switch is connected to the gate voltage.

8. An electronic device, characterized in that: A power amplifier standing wave protection circuit based on temperature detection comprising the method described in any one of claims 1 to 7.

9. A control method, applied to the electronic device according to claim 8, characterized in that: The control method comprises: Obtaining a voltage value corresponding to the temperature detection signal; Comparing the voltage value with a threshold voltage in the control protection circuit to determine whether the standing wave is abnormal; When it is determined that the voltage value exceeds the discrimination threshold voltage, outputting a gate control signal to the power supply circuit and outputting the alarm signal; The power supply circuit is controlled to turn on or off the gate voltage based on the gate control signal, so as to control the amplifiers in the pre-stage driving amplifier chain and the final-stage power amplifier circuit to turn on or off.

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