A power amplifier and electronic device

Abstract

The embodiment of the application discloses a power amplifier and electronic equipment, the power amplifier includes at least one power amplifier circuit, wherein each power amplifier circuit includes power tube and bias unit;The input end of power tube is electrically connected with bias unit, the input end of power tube is also used for accessing radio frequency signal, and the output end of power tube is used for being electrically connected with load;The bias unit includes adaptive bias circuit and gain compensation circuit, wherein the gain compensation circuit is electrically connected with the adaptive bias circuit, and the bias current output end of the adaptive bias circuit is electrically connected with the input end of power tube;The gain compensation circuit is used for adjusting the bias current output by the adaptive bias circuit when detecting environmental temperature change, and the change state of environmental temperature is consistent with the change state of bias current.Through the setting of the gain compensation circuit, the influence of temperature rise on the small signal gain of power tube can be effectively avoided.

Description

Technical Field

[0001] This invention relates to the field of integrated circuits, and more particularly to a power amplifier and electronic device. Background Technology

[0002] Since power amplifiers often operate when the RF signal is in a fallback state, the amplification efficiency of the power amplifier is one of the most critical indicators. When the power amplifier is working, it is necessary to bias the power amplifier to ensure that the power amplifier can output maximum power and has an appropriate bias point in the fallback state, so as to maintain its high efficiency without sacrificing linearity.

[0003] For power amplifiers manufactured using GaAs HBT technology, the most common method is to use an adaptive bias circuit as the bias current source. Because GaAs HBTs are highly thermally sensitive, the power amplifier's gain is significantly affected by ambient temperature and self-heating effects. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a power amplifier and electronic device, the specific solution of which is as follows:

[0005] In a first aspect, embodiments of this application provide a power amplifier, which includes at least one stage of power amplifier circuit, wherein each stage of power amplifier circuit includes a power transistor and a bias unit;

[0006] The input terminal of the power transistor is electrically connected to the bias unit, and the input terminal of the power transistor is also used to receive radio frequency signals. The output terminal of the power transistor is used to be electrically connected to the load.

[0007] The bias unit includes an adaptive bias circuit and a gain compensation circuit, wherein the gain compensation circuit is electrically connected to the adaptive bias circuit, and the bias current output terminal of the adaptive bias circuit is electrically connected to the input terminal of the power transistor.

[0008] The gain compensation circuit is used to adjust the bias current output by the adaptive bias circuit when a change in ambient temperature is detected, and the change in ambient temperature is consistent with the change in bias current.

[0009] According to a specific embodiment of this application, the adaptive bias circuit includes a first transistor, a second transistor, and a third transistor; wherein,

[0010] The second electrode of the first transistor is connected to a first voltage signal;

[0011] The first electrode of the first transistor, the first electrode and the second electrode of the second transistor, and the second electrode of the third transistor are all connected to a second voltage signal;

[0012] The third electrode of the second transistor is electrically connected to the second electrode of the third transistor, and the third electrode of the third transistor is grounded;

[0013] The third electrode of the first transistor is electrically connected to the bias current output terminal.

[0014] According to a specific embodiment of the present application, the adaptive bias circuit further includes a fourth transistor;

[0015] The first electrode of the fourth transistor is electrically connected to the first electrode of the first transistor and the first electrode of the second transistor, respectively.

[0016] The second electrode of the fourth transistor is used to receive the first voltage signal;

[0017] The third electrode of the fourth transistor is electrically connected to the first electrode of the third transistor.

[0018] According to a specific embodiment of the present application, the adaptive bias circuit further includes a first resistor, a second resistor, a third resistor, a fourth resistor, and a fifth resistor;

[0019] The third electrode of the first transistor is electrically connected to the bias current output terminal through the first resistor.

[0020] The second electrode of the first transistor is connected to the first voltage signal through the second resistor;

[0021] The second electrode of the second transistor and the first electrode of the fourth transistor are connected to the second voltage signal through the third resistor;

[0022] The second electrode of the fourth transistor is connected to the first voltage signal through the fourth resistor;

[0023] The second electrode of the third transistor is connected to the second voltage signal through the fifth resistor.

[0024] According to a specific embodiment of the present application, the first electrode of the first transistor and the second electrode of the second transistor are grounded through a capacitor;

[0025] The third electrode of the first transistor is electrically connected to the bias current output terminal via an inductor.

[0026] According to a specific embodiment of the present application, the gain compensation circuit includes a fifth transistor and a sixth transistor;

[0027] The first electrode of the fifth transistor and the second electrode of the sixth transistor are both used to receive the second voltage signal;

[0028] The second electrode of the fifth transistor is electrically connected to the second electrode of the third transistor;

[0029] The third electrode of the fifth transistor is electrically connected to the first electrode of the sixth transistor;

[0030] The third electrode of the sixth transistor is grounded.

[0031] According to a specific embodiment of the present application, the gain compensation circuit includes a sixth resistor, a seventh resistor, and an eighth resistor;

[0032] The second electrode of the fifth transistor is electrically connected to the second electrode of the third transistor through the sixth resistor;

[0033] The third electrode of the fifth transistor and the first electrode of the sixth transistor are grounded through the seventh resistor;

[0034] The first electrode of the fifth transistor and the second electrode of the sixth transistor are connected to the second voltage signal through the eighth resistor.

[0035] According to a specific embodiment of the present application, the power amplifier circuit further includes an input stage impedance matching circuit and an output stage impedance matching circuit;

[0036] The input terminal of the power transistor is connected to the radio frequency signal through the input stage impedance matching circuit;

[0037] The output terminal of the power transistor is electrically connected to the load through the output stage impedance matching circuit.

[0038] According to one specific embodiment of this application, the power transistor is a GaAs HBT transistor.

[0039] Secondly, embodiments of this application also provide an electronic device, which includes the power amplifier described in the first aspect and any embodiment of the first aspect.

[0040] This application provides a power amplifier and an electronic device. The power amplifier includes at least one stage of power amplifier circuit, wherein each stage includes a power transistor and a bias unit. The input terminal of the power transistor is electrically connected to the bias unit, and the input terminal of the power transistor is also used to receive radio frequency signals. The output terminal of the power transistor is used to be electrically connected to a load. The bias unit includes an adaptive bias circuit and a gain compensation circuit, wherein the gain compensation circuit is electrically connected to the adaptive bias circuit, and the bias current output terminal of the adaptive bias circuit is electrically connected to the input terminal of the power transistor. The gain compensation circuit is used to adjust the bias current output by the adaptive bias circuit when a change in ambient temperature is detected, and the change in ambient temperature is consistent with the change in bias current. By setting the gain compensation circuit, the gain decrease caused by temperature rise can be effectively compensated. Attached Figure Description

[0041] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope of protection of the present invention. In the various drawings, similar components are numbered similarly.

[0042] Figure 1 A schematic diagram of the circuit structure of a power amplifier provided in an embodiment of this application is shown;

[0043] Figure 2 A schematic diagram of the gain characteristic curve of the power transistor of a power amplifier provided in an embodiment of this application is shown.

[0044] Figure 3 A schematic diagram of the circuit structure of the bias unit of a power amplifier provided in an embodiment of this application is shown;

[0045] Figure 4 This illustration shows another circuit structure diagram of the bias unit of a power amplifier provided in an embodiment of this application;

[0046] Figure 5 This illustration shows a gain fluctuation diagram of a power amplifier provided in this application when the bias unit only includes an adaptive bias circuit;

[0047] Figure 6 This illustration shows a gain fluctuation diagram of a power amplifier bias unit including an adaptive bias circuit and a gain compensation circuit, according to an embodiment of this application. Detailed Implementation

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0049] The components of the embodiments of the invention described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0050] In the following, the terms “comprising,” “having,” and their cognates, which may be used in various embodiments of the invention, are intended only to indicate a particular feature, number, step, operation, element, component, or combination thereof, and should not be construed as excluding, firstly, the presence of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, or adding the possibility of one or more features, numbers, steps, operations, elements, components, or combinations thereof.

[0051] Furthermore, the terms "first," "second," and "third" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0052] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of the invention pertain. Terms (such as those defined in commonly used dictionaries) shall be interpreted as having the same meaning as in their contextual meaning in the relevant technical field and shall not be interpreted as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of the invention.

[0053] refer to Figure 1 The present application provides a power amplifier, which includes at least one stage of power amplifier circuit, wherein each stage of power amplifier circuit includes a power transistor and a bias unit.

[0054] The input terminal of the power transistor is electrically connected to the bias unit, and the input terminal of the power transistor is also used to receive radio frequency signals. The output terminal of the power transistor is used to be electrically connected to the load.

[0055] The bias unit includes an adaptive bias circuit and a gain compensation circuit, wherein the gain compensation circuit is electrically connected to the adaptive bias circuit, and the bias current output terminal of the adaptive bias circuit is electrically connected to the input terminal of the power transistor.

[0056] The gain compensation circuit is used to adjust the bias current output by the adaptive bias circuit when a change in ambient temperature is detected, and the change in ambient temperature is consistent with the change in bias current.

[0057] In a specific embodiment, such as Figure 1 As shown, the power amplifier may include a three-stage power amplifier circuit, wherein the first-stage power amplifier circuit includes a power transistor DRV1 and a bias unit 1, the second-stage power amplifier circuit includes a power transistor DRV2 and a bias unit 2, and the third-stage power amplifier circuit includes a power transistor DRV3 and a bias unit 3.

[0058] In the three-stage power amplifier circuit, power transistor DRV1 is the driver stage, power transistor DRV2 is the amplification stage, and DRV3 is the power stage. Bias unit 1, bias unit 2, and bias unit 3 use the same bias unit connection structure.

[0059] It should be noted that the power amplifier may include a single-stage power amplifier circuit or a multi-stage power amplifier circuit, and the specific number may be adaptively replaced according to the actual application scenario, which is not limited here.

[0060] The parameter values ​​of each component in the bias unit 1, the bias unit 2 and the bias unit 3 can be adaptively replaced according to the function of the power transistor DRV in the actual application scenario, and no specific limitation is made here.

[0061] Specifically, the input terminal of the first-stage power amplifier circuit is used to receive the radio frequency signal RFin. The output terminal of the first-stage power amplifier circuit is electrically connected to the input terminal of the second-stage power amplifier circuit. The output terminal of the second-stage power amplifier circuit is electrically connected to the input terminal of the third-stage power amplifier circuit. The output terminal of the third-stage power amplifier circuit is electrically connected to the load device.

[0062] The radio frequency signal can be any radio frequency signal received or transmitted by any electronic device using the power amplifier during signal interaction.

[0063] According to a specific embodiment of the present application, the power amplifier circuit further includes an input stage impedance matching circuit and an output stage impedance matching circuit;

[0064] The input terminal of the power transistor is connected to the radio frequency signal through the input stage impedance matching circuit;

[0065] The output terminal of the power transistor is electrically connected to the load through the output stage impedance matching circuit.

[0066] In a specific implementation, when the power amplifier circuit receives the radio frequency signal, it also needs to filter the radio frequency signal through an input stage impedance matching circuit to ensure stable transmission of the high-frequency signal and prevent signal reflection. When the power amplifier circuit outputs the amplified signal, it needs to filter the amplified signal through an output stage impedance matching circuit before finally outputting the processed amplified signal to the load device.

[0067] like Figure 1 As shown, when the power amplifier has a multi-stage power amplifier circuit, corresponding inter-stage impedance matching circuits are also required between each amplifier circuit to ensure that high-frequency microwave signals can be stably transmitted to the load point.

[0068] The impedance matching circuit can adopt any impedance matching circuit structure in the prior art. Specifically, the optimal impedance matching circuit that can maintain stable signal transmission can be selected according to the actual application scenario.

[0069] For example, this embodiment can use an impedance matching circuit including a first capacitor, a second capacitor, and a first inductor to achieve the purpose of impedance matching.

[0070] According to one specific embodiment of this application, the power transistor is a GaAs HBT transistor.

[0071] In a specific implementation, the power transistor is a gallium arsenide heterojunction bipolar transistor (GaAs HBT).

[0072] GaAs HBTs are highly thermally sensitive, and the transistors are significantly affected by temperature and self-heating effects.

[0073] like Figure 2 As shown, a temperature scan was performed on a single transistor of a GaAs HBT while keeping the bias voltage constant. Taking the 2.4GHz band as an example, the temperature scan of the GaAs HBT was performed. It can be seen that the higher the temperature, the lower the maximum usable gain (MaxGain) of the GaAs HBT. Therefore, it can be seen that if the power transistor is not processed, the amplifier circuit built using its HBT transistor will also exhibit a decrease in gain as the temperature increases.

[0074] exist Figure 2 In this context, MaxGain represents the maximum available gain, and SP.tp represents the temperature.

[0075] In practical applications, the power transistor in the embodiments of this application can also be supplemented with other peripheral circuits to achieve power amplification. The specific structure of the peripheral circuits can adopt the connection structure of existing amplifier circuits, which will not be elaborated here.

[0076] Specifically, the power transistor also has a first electrode, a second electrode, and a third electrode. It should be noted that in this embodiment, the first electrode refers to the base, the second electrode refers to the collector, and the third electrode refers to the emitter.

[0077] The base of the power transistor is used to receive radio frequency signals and the bias current output by the bias unit.

[0078] In this embodiment, the bias unit is used to provide bias current for the amplifier structure where the power transistor is located, and the bias unit includes an adaptive bias circuit and a gain compensation circuit.

[0079] By configuring the adaptive bias circuit, different bias currents can be provided based on the amplification gain of the amplifier structure where the power transistor is located in practical applications.

[0080] By setting up the gain compensation circuit, a bias current can be provided to the base of the power transistor that is consistent with the change in ambient temperature.

[0081] When the ambient temperature rises, the gain compensation circuit performs temperature compensation on the bias current provided by the adaptive bias circuit, resulting in a larger bias current provided by the adaptive bias circuit. When the ambient temperature decreases, the gain compensation circuit performs temperature compensation on the bias current provided by the adaptive bias circuit, resulting in a smaller bias current provided by the adaptive bias circuit.

[0082] According to a specific embodiment of this application, the adaptive bias circuit includes a first transistor, a second transistor, and a third transistor; wherein,

[0083] The second electrode of the first transistor is connected to a first voltage signal;

[0084] The first electrode of the first transistor, the first electrode and the second electrode of the second transistor, and the second electrode of the third transistor are all connected to a second voltage signal;

[0085] The third electrode of the second transistor is electrically connected to the second electrode of the third transistor, and the third electrode of the third transistor is grounded;

[0086] The third electrode of the first transistor is electrically connected to the bias current output terminal.

[0087] In a specific embodiment, the adaptive bias circuit can independently bias the power transistor and provide bias current to the power transistor.

[0088] In this embodiment, the first transistor Q1, the second transistor Q2, and the third transistor Q3 are all NPN transistors. It should be noted that the types of the first transistor Q1, the second transistor Q2, and the third transistor Q3 can also be adaptively replaced according to the actual application scenario, and are not limited here.

[0089] In this embodiment, the first electrode refers to the base, the second electrode refers to the collector, and the third electrode refers to the emitter.

[0090] The base of the first transistor Q1 is electrically connected to the base of the second transistor Q2, and the base of the second transistor Q2 is electrically connected to the collector of the second transistor, so that a current mirror structure is formed between the first transistor Q1 and the second transistor Q2.

[0091] The current output from the emitter of the second transistor Q2 is a mirror image of the current output from the emitter of the first transistor Q1, that is, the magnitude of the current passing through the third transistor Q3 is equal to the magnitude of the current passing through the first resistor R1.

[0092] The collector of the third transistor Q3 is electrically connected to the emitter of the second transistor Q2, and the emitter of the third transistor Q3 is grounded. Through the transistor characteristics of the second transistor Q2 and the third transistor Q3, a preset reference voltage and reference current can be provided for the adaptive bias circuit.

[0093] Without gain compensation for the voltage at node A, the current output from the emitter of the first transistor Q1 is the reference current.

[0094] Specifically, the voltage magnitudes of the first voltage signal Vbb1 and the second voltage signal are adaptively replaced according to the amplification gain of the power transistor. In this embodiment, the values ​​of the first voltage signal Vbb1 and the second voltage signal are not limited.

[0095] The magnitudes of the first voltage signal Vbb1 and the second voltage signal Vbb2 can be the same or different.

[0096] The first voltage signal Vbb1 can be 5V or 3V, depending on the process characteristics of the power transistor, and is not limited here.

[0097] The second voltage signal Vbb2 is a bias voltage signal, which is adaptively replaced according to the gain of the power transistor.

[0098] According to a specific embodiment of the present application, the adaptive bias circuit further includes a fourth transistor;

[0099] The first electrode of the fourth transistor is electrically connected to the first electrode of the first transistor and the first electrode of the second transistor, respectively.

[0100] The second electrode of the fourth transistor is used to receive the first voltage signal;

[0101] The third electrode of the fourth transistor is electrically connected to the first electrode of the third transistor.

[0102] In a specific embodiment, the fourth transistor Q4, the ninth resistor R9, and the fourth resistor R4 together form a feedback loop.

[0103] The negative feedback effect of the fourth transistor Q4 makes the voltage signals input to the base of the first transistor Q1, the base of the second transistor Q2, and the base of the fourth transistor Q4 more stable.

[0104] According to a specific embodiment of the present application, the adaptive bias circuit further includes a first resistor, a second resistor, a third resistor, a fourth resistor, and a fifth resistor;

[0105] The third electrode of the first transistor is electrically connected to the bias current output terminal through the first resistor.

[0106] The second electrode of the first transistor is connected to the first voltage signal through the second resistor;

[0107] The second electrode of the second transistor and the first electrode of the fourth transistor are connected to the second voltage signal through the third resistor;

[0108] The second electrode of the fourth transistor is connected to the first voltage signal through the fourth resistor;

[0109] The second electrode of the third transistor is connected to the second voltage signal through the fifth resistor.

[0110] In a specific embodiment, the first resistor R1 is a ballast resistor that ballasts the GaAs HBT power transistor. The value of the first resistor R1 is related to performance characteristics such as gain linearity and thermal stability.

[0111] The second resistor R2, the second transistor Q2, and the capacitor C1 connected to the base of the first transistor Q1 and the second transistor Q2 rectify the bias current and the radio frequency signal, thereby enabling adaptive biasing of the radio frequency signal at the power transistor.

[0112] The third resistor R3, the fourth resistor R4, and the fifth resistor R5 are all voltage dividers used to adjust the voltage magnitudes of the first voltage signal Vbb1 and the second voltage signal Vbb2 input to the adaptive bias circuit.

[0113] Specifically, the values ​​of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, and the fifth resistor R5 can be adaptively replaced according to the actual gain of the power transistor. No specific limit is placed on the resistance value of each resistor here.

[0114] According to a specific embodiment of the present application, the first electrode of the first transistor and the second electrode of the second transistor are grounded through a capacitor;

[0115] The third electrode of the first transistor is electrically connected to the bias current output terminal via an inductor.

[0116] In specific implementations, such as Figure 4 As shown, the first transistor Q1 rectifies the input current in the adaptive bias circuit. When the power of the RF path increases, the power of the RF signal entering the bias circuit also increases accordingly. Under the rectification effect of the first transistor Q1, the DC current of Q1 increases, so that the bias current received by the power amplifier reaches a dynamic adjustment process.

[0117] However, in broadband power amplifiers, the dynamic changes required by the bias circuit differ between high-frequency and low-frequency radio frequency signals. Therefore, inductor L1 is added to the circuit, working in conjunction with capacitor C1, to regulate the radio frequency signals entering the bias circuit at different frequencies and adjust the impedance of the bias circuit.

[0118] Inductor L1 is connected between the bias circuit and the RF main circuit. When the circuit is working normally, RF signals will enter the adaptive bias circuit through this inductor. The power of the incoming RF signal is rectified by the first transistor Q1, thereby achieving the function of adaptive bias.

[0119] According to a specific embodiment of the present application, the gain compensation circuit includes a fifth transistor and a sixth transistor;

[0120] The first electrode of the fifth transistor and the second electrode of the sixth transistor are both used to connect to the second voltage signal Vbb2;

[0121] The second electrode of the fifth transistor is electrically connected to the second electrode of the third transistor;

[0122] The third electrode of the fifth transistor is electrically connected to the first electrode of the sixth transistor;

[0123] The third electrode of the sixth transistor is grounded.

[0124] In a specific embodiment, such as Figure 3 As shown, the gain compensation circuit is used to adjust the current at node A.

[0125] The base of the fifth transistor Q5 is used to connect to the second voltage signal Vbb2. The emitter of the fifth transistor Q5 is electrically connected to the base of the sixth transistor Q6. By controlling the voltage at nodes B and C, the current at node A can be adjusted according to the transistor characteristics of the fifth transistor Q5 and the sixth transistor Q6.

[0126] According to a specific embodiment of the present application, the gain compensation circuit includes a sixth resistor, a seventh resistor, and an eighth resistor;

[0127] The second electrode of the fifth transistor is electrically connected to the second electrode of the third transistor through the sixth resistor;

[0128] The third electrode of the fifth transistor and the first electrode of the sixth transistor are grounded through the seventh resistor;

[0129] The first electrode of the fifth transistor and the second electrode of the sixth transistor are connected to the second voltage signal Vbb2 through the eighth resistor.

[0130] In a specific embodiment, such as Figure 3 and Figure 4 As shown, the sixth resistor R6 can be connected to either the collector or the base of the fifth transistor Q5. R6 is a voltage divider resistor used to adjust the voltage at node A. Specifically, the position of the sixth resistor R6 can be adaptively selected according to the actual application scenario; no specific limitation is made here.

[0131] By adjusting the resistance values ​​of the seventh resistor R7 and the eighth resistor R8, the current at each electrode of the fifth transistor Q5 and the sixth transistor Q6 can be adjusted.

[0132] like Figure 3 As shown, i1 is the current flowing through the eighth resistor R8; i2 is the current flowing through the seventh resistor R7; i b5 i c5 and ie5 These are the base current, collector current, and emitter current of the fifth transistor Q5, respectively; i b6 and i c6 These are the base current and collector current of the sixth transistor Q6, respectively.

[0133] V A V B and V C Let A be the potential of node B, and C be the potentials of node C.

[0134] For the fifth transistor Q5 and the sixth transistor Q6, the current at the collector of the transistor will change accordingly due to the influence of ambient temperature.

[0135] Specifically, the transistor collector current i c =I S exp(V BE / V T );

[0136] Where I S =bT 4+m exp(-E g / kT); V T = kT / q; where T represents temperature, I S V is a temperature-dependent current parameter. T Let be the thermoelectric voltage parameters, where m, k, and q are all constants.

[0137] When the temperature remains constant, I S and V T All are constants.

[0138] The following relationship can be obtained from the connection relationship of the gain compensation circuit in this embodiment:

[0139] i1*R8=vbb2-V A i1 = i b5 +i c6 i b5 =i c5 +i e5 i e5 =i b6 +i2;V BE6 =V C V BE5 =V B -V C ;

[0140] From the above equations, it can be concluded that at the reference temperature Tref, adjusting the resistance value of the seventh resistor R7 can make the voltage flowing through the sixth resistor R6 very small and negligible. At this time, by adjusting the voltage at node A of the adaptive bias circuit through the gain compensation circuit, the bias current provided by the adaptive bias circuit to the power transistor is the same as that without the gain compensation circuit at room temperature.

[0141] At this time, the gain compensation circuit has a positive temperature coefficient. When the ambient temperature rises relative to the reference temperature Tref, the current supplied by the gain compensation circuit to the collector of the third transistor Q3 through the sixth resistor R6 is greater, and the bias current supplied by the first transistor Q1 to the power transistor is also greater.

[0142] Similarly, when the ambient temperature decreases relative to the reference temperature Tref, the gain compensation circuit "draws" current from node A. The lower the temperature, the more obvious the current "drawing" effect, and the smaller the bias current provided by the first transistor Q1.

[0143] In summary, the gain compensation circuit has a positive temperature coefficient, which adjusts the bias current according to the temperature state, thereby achieving temperature compensation for the power amplifier.

[0144] The embodiments of this application, through the structural arrangement of the gain compensation circuit, enable the bias unit to have a positive temperature coefficient. When the ambient temperature of the bias unit increases, the voltage compensated by the gain compensation circuit increases, and the bias current output by the bias unit increases, thereby more stably ensuring the amplification gain of the power amplifier.

[0145] like Figure 5 and Figure 6 As shown, when the bias unit used only includes an adaptive bias circuit but does not have a gain compensation circuit, the gain fluctuation at low and high temperatures is 2dB. When the bias unit used includes both an adaptive bias circuit and a gain compensation circuit, the gain fluctuation at low and high temperatures is reduced to 0.9dB. Therefore, it can be seen that the power amplifier provided in this application embodiment can adapt to scenarios with higher requirements for gain stability.

[0146] exist Figure 5 and Figure 6 In this context, freq represents the frequency of the radio frequency signal, SP.S(2,1) represents the small-signal gain of the power transistor, and tp represents the temperature.

[0147] In addition, this application also provides an electronic device, which includes the power amplifier in the foregoing embodiments.

[0148] In summary, this application provides a power amplifier and electronic device. By combining a gain compensation circuit and an adaptive bias circuit, the gain stability of the GaAs HBT power transistor can be effectively improved, thereby enabling the power amplifier to provide stable amplification functionality to the electronic device without being affected by ambient temperature. Furthermore, the specific implementation process of the electronic device can be referred to the specific implementation process of the power amplifier embodiment described above, and will not be repeated here.

[0149] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative; for example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that, as an alternative implementation, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0150] In addition, the functional modules or units in the various embodiments of the present invention can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0151] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a smartphone, personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0152] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A power amplifier, characterized in that, The power amplifier includes at least one stage of power amplifier circuit, wherein each stage of power amplifier circuit includes a power transistor and a bias unit; The input terminal of the power transistor is electrically connected to the bias unit, and the input terminal of the power transistor is also used to receive radio frequency signals. The output terminal of the power transistor is used to be electrically connected to the load. The bias unit includes an adaptive bias circuit and a gain compensation circuit, wherein the gain compensation circuit is electrically connected to the adaptive bias circuit, and the bias current output terminal of the adaptive bias circuit is electrically connected to the input terminal of the power transistor. The gain compensation circuit is used to adjust the bias current output by the adaptive bias circuit when a change in ambient temperature is detected, and the change in ambient temperature is consistent with the change in bias current. The adaptive bias circuit includes a first transistor, a second transistor, and a third transistor; wherein, The second electrode of the first transistor is connected to a first voltage signal; The first electrode of the first transistor and the first and second electrodes of the second transistor are both connected to a second voltage signal; the second electrode of the third transistor is connected to the second voltage signal through a fifth resistor. The third electrode of the second transistor is electrically connected to the second electrode of the third transistor, and the third electrode of the third transistor is grounded; The third electrode of the first transistor is electrically connected to the bias current output terminal; The adaptive bias circuit also includes a fourth transistor; The first electrode of the fourth transistor is electrically connected to the first electrode of the first transistor and the first electrode of the second transistor, respectively. The second electrode of the fourth transistor is used to receive the first voltage signal; The third electrode of the fourth transistor is electrically connected to the first electrode of the third transistor. The output of the gain compensation circuit is connected to the second electrode of the third transistor.

2. The power amplifier according to claim 1, characterized in that, The adaptive bias circuit further includes a first resistor, a second resistor, a third resistor, and a fourth resistor; The third electrode of the first transistor is electrically connected to the bias current output terminal through the first resistor. The second electrode of the first transistor is connected to the first voltage signal through the second resistor; The second electrode of the second transistor and the first electrode of the fourth transistor are connected to the second voltage signal through the third resistor; The second electrode of the fourth transistor is connected to the first voltage signal through the fourth resistor.

3. The power amplifier according to claim 1, characterized in that, The first electrode of the first transistor and the second electrode of the second transistor are grounded through a capacitor; The third electrode of the first transistor is electrically connected to the bias current output terminal via an inductor.

4. The power amplifier according to claim 1, characterized in that, The gain compensation circuit includes a fifth transistor and a sixth transistor; The first electrode of the fifth transistor and the second electrode of the sixth transistor are both used to receive the second voltage signal; The second electrode of the fifth transistor is electrically connected to the second electrode of the third transistor; The third electrode of the fifth transistor is electrically connected to the first electrode of the sixth transistor; The third electrode of the sixth transistor is grounded.

5. The power amplifier according to claim 4, characterized in that, The gain compensation circuit includes a sixth resistor, a seventh resistor, and an eighth resistor; The second electrode of the fifth transistor is electrically connected to the second electrode of the third transistor through the sixth resistor; The third electrode of the fifth transistor and the first electrode of the sixth transistor are grounded through the seventh resistor; The first electrode of the fifth transistor and the second electrode of the sixth transistor are connected to the second voltage signal through the eighth resistor.

6. The power amplifier according to claim 1, characterized in that, The power amplifier circuit also includes an input stage impedance matching circuit and an output stage impedance matching circuit. The input terminal of the power transistor is connected to the radio frequency signal through the input stage impedance matching circuit; The output terminal of the power transistor is electrically connected to the load through the output stage impedance matching circuit.

7. The power amplifier according to claim 1, characterized in that, The power transistor is a GaAs HBT transistor.

8. An electronic device, characterized in that, The electronic device includes the power amplifier as described in any one of claims 1-7.

Images