Power amplifier circuit and electronic device

Abstract

The present invention provides a power amplifier circuit and an electronic device, including a power transistor, a main bias unit, and an auxiliary bias unit; the main bias unit is respectively connected to a power supply voltage terminal and a reference voltage terminal, and the main bias unit is further connected between the control terminal of the power transistor and the first terminal of the power transistor, and is used to provide a first bias voltage to the control terminal of the power transistor and the first terminal of the power transistor; the first terminal of the power transistor is directly or indirectly connected to the power supply voltage terminal, and the second terminal of the power transistor is grounded; the auxiliary bias unit is respectively connected to the power supply voltage terminal and the reference voltage terminal, and the auxiliary bias unit is further connected between the control terminal of the power transistor and the first terminal of the power transistor, and is used to provide a second bias voltage to the power transistor when the current temperature where the auxiliary bias unit is located is less than a threshold temperature.

Description

Technical Field

[0001] The present invention relates to the field of power amplifiers, and in particular, to a power amplifier circuit and an electronic device. Background Art

[0002] Radio frequency power amplifiers usually use heterojunction bipolar transistors (HBTs), complementary metal-oxide-semiconductor transistors (CMOS), high electron mobility transistors (HEMTs), etc. as amplification transistors, which are called power transistors. With the wide application of new generation communication standards such as 5G and wifi6, the linearity requirements for radio frequency power amplifiers are also getting higher and higher.

[0003] In the prior art, a linear power amplifier can be used to meet the current market's linearity requirements for radio frequency power amplifiers. In practical applications, generally, when the signal is in the transmission mode, the power amplifier is turned on, and when the signal is not in the transmission mode, the power amplifier is turned off. Therefore, the linear power amplifier may need to be continuously turned on and off in practical application scenarios. In some application scenarios, the linear power amplifier is turned off most of the time and needs to be turned on for a small part of the time.

[0004] When the linear power amplifier is turned off for a period of time and then turned on, since the linear power amplifier is basically in a cooled state before being turned on, it takes a period of time to enter the thermal stable state when it is turned on. During this period, the gain of the linear power amplifier will change, affecting the linearity.

[0005] It can be seen that the prior art has the problem of non-linearity of the power amplifier caused by temperature changes (such as slow entry into the thermal stable state). Summary of the Invention

[0006] The present invention provides a power amplifier circuit and an electronic device to solve the problem of non-linearity caused by temperature changes (such as slow entry into the thermal stable state).

[0007] According to a first aspect of the present invention, there is provided a power amplifier circuit, including a power transistor, a main biasing unit, and an auxiliary biasing unit;

[0008] The main biasing unit is respectively connected to a power supply voltage terminal and a reference voltage terminal, and the main biasing unit is further connected between the control terminal of the power transistor and the first terminal of the power transistor. The main biasing unit is used to provide a first biasing voltage to the control terminal of the power transistor and the first terminal of the power transistor; the first terminal of the power transistor is directly or indirectly connected to the power supply voltage terminal, and the second terminal of the power transistor is grounded;

[0009] The auxiliary bias unit is respectively connected to the power supply voltage terminal and the reference voltage terminal. The auxiliary bias unit is also connected between the control terminal and the first terminal of the power transistor. The auxiliary bias unit is configured to provide a second bias voltage to the power transistor when the current temperature at which the auxiliary bias unit is located is lower than a threshold temperature.

[0010] Optionally, the auxiliary bias unit includes a temperature response module, a first auxiliary bias amplifier, a second auxiliary bias amplifier, a first resistor, a second resistor, and a third resistor;

[0011] The first end of the first resistor is connected to the reference voltage terminal, the second end of the first resistor is connected to the first end of the temperature response module, the second end of the temperature response module is connected to the first end of the second resistor, and the second end of the second resistor is grounded;

[0012] The control terminal of the first auxiliary bias amplifier is connected between the second end of the temperature response module and the first end of the second resistor. The first end of the first auxiliary bias amplifier is connected between the control terminal of the second auxiliary bias amplifier and the first end of the third resistor. The second end of the third resistor is connected to the reference voltage terminal. The second end of the first auxiliary bias amplifier is grounded. The first end of the second auxiliary bias amplifier is connected to the power supply voltage terminal. The control terminal of the second auxiliary bias amplifier is connected to the reference voltage terminal through the third resistor. The first end of the second auxiliary bias amplifier is directly or indirectly connected to the first end of the power transistor. The second end of the second auxiliary bias amplifier is directly or indirectly connected to the control terminal of the power transistor;

[0013] The control terminal of the power transistor is connected to a radio frequency signal;

[0014] The temperature response module is configured to: in response to an increase in the current temperature, reduce the voltage drop across the temperature response module, so that: the voltage between the control terminal and the second end of the first auxiliary bias amplifier becomes larger;

[0015] Wherein: when the current temperature is higher than the threshold temperature, the voltage between the control terminal and the second end of the first auxiliary bias amplifier is higher than a threshold voltage, the first auxiliary bias amplifier is turned on, and the second auxiliary bias amplifier is turned off;

[0016] When the current temperature is lower than the threshold temperature, the voltage between the control terminal and the second end of the first auxiliary bias amplifier is lower than the threshold voltage, the first auxiliary bias amplifier is turned off, and the second auxiliary bias amplifier is turned on to provide a second bias voltage to the power transistor.

[0017] Optionally, the temperature response module includes a temperature response triode;

[0018] The collector of the temperature-responsive triode is connected to the second end of the first resistor, and the emitter of the temperature-responsive triode is connected to the first end of the second resistor;

[0019] If the temperature-responsive triode is an NPN-type triode, then: the base of the temperature-responsive triode is further connected to the collector of the temperature-responsive triode;

[0020] If the temperature-responsive triode is a PNP-type triode, then: the base of the temperature-responsive triode is further connected to the emitter of the temperature-responsive triode.

[0021] Optionally, the temperature-responsive module includes a temperature-responsive diode;

[0022] The positive pole of the temperature-responsive diode is connected to the second end of the first resistor, and the negative pole of the temperature-responsive diode is connected to the first end of the second resistor.

[0023] Optionally, the main biasing unit includes a main biasing amplifier, a main resistor, a capacitor, and a temperature compensation module;

[0024] The temperature compensation module is connected between the control terminal of the main biasing amplifier and the ground; the temperature compensation module is used to compensate for the offset of the quiescent operating point of the main biasing amplifier;

[0025] The capacitor is connected across the temperature compensation module;

[0026] The first end of the main resistor is connected to the reference voltage terminal, and the second end of the main resistor is connected to the first end of the temperature compensation module;

[0027] The first end of the main biasing amplifier is connected to the supply voltage terminal, and the second end of the main biasing amplifier is directly or indirectly connected to the control terminal of the power transistor to provide the first biasing voltage to the power transistor when the main biasing amplifier is turned on.

[0028] Optionally, the temperature compensation module includes a first temperature compensation triode and a second temperature compensation triode;

[0029] The collector of the first temperature compensation triode is connected to the second end of the main resistor, and the collector of the first temperature compensation triode is further connected to the control terminal of the main biasing amplifier;

[0030] The emitter of the first temperature compensation triode is connected to the collector of the second temperature compensation triode; the base of the first temperature compensation triode is connected to the collector of the first temperature compensation triode, the emitter of the second temperature compensation triode is grounded, and the base of the second temperature compensation triode is connected to the collector of the second temperature compensation triode.

[0031] Optionally, the temperature compensation module includes a first temperature compensation diode and a second temperature compensation diode;

[0032] The positive electrode of the first temperature compensation diode is connected to the second end of the main resistor, and the positive electrode of the first temperature compensation diode is also connected to the base of the main bias amplifier; the negative electrode of the first temperature compensation diode is connected to the positive electrode of the second temperature compensation diode, and the negative electrode of the second temperature compensation diode is grounded.

[0033] Optionally, the power amplifier circuit further includes an inductor and an output resistor;

[0034] The inductor is connected between the first end of the power transistor and the power supply voltage terminal, and the output resistor is connected between the auxiliary bias unit and the control terminal of the power transistor.

[0035] According to a second aspect of the present invention, there is provided an electronic device including the power amplifier circuit according to the first aspect of the present invention.

[0036] When the power transistor is just turned on (when the temperature is less than the threshold temperature), the power amplifier circuit and the electronic device provided by the present invention simultaneously provide a bias voltage to the power transistor through the main bias unit and the auxiliary bias unit, thereby helping the power transistor quickly reach the thermal stable state. After the temperature reaches the threshold temperature, only the main bias unit provides a bias voltage to the power transistor to maintain the thermal stable state of the power transistor, so that the power amplifier can enter the thermal stable state and maintain it in a short time, which helps to improve the linearity of the power amplifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0038] Figure 1 is a schematic structural diagram of a power amplifier in an embodiment of the present invention Figure 1 ;

[0039] Figure 2 is a schematic structural diagram of a power amplifier in an embodiment of the present inventionFigure 2 ;

[0040] Figure 3a is the third schematic diagram of the structure of the power amplifier in an embodiment of the present invention;

[0041] Figure 3b is the schematic diagram of the structure of the power amplifier in an embodiment of the present invention Figure 4 ;

[0042] Figure 3c is the schematic diagram of the structure of the power amplifier in an embodiment of the present invention Figure 5 ;

[0043] Figure 4 is the schematic diagram of the structure of the power amplifier in an embodiment of the present invention Figure 6 ;

[0044] Figure 5 is the schematic diagram of the structure of the power amplifier in an embodiment of the present invention Figure 7 ;

[0045] Figure 6 is the schematic diagram of the structure of the power amplifier in an embodiment of the present invention Figure 8 ;

[0046] Figure 7 is the ninth schematic diagram of the structure of the power amplifier in an embodiment of the present invention;

[0047] Figure 8 is the tenth schematic diagram of the structure of the power amplifier in an embodiment of the present invention;

[0048] Description of reference numerals:

[0049] 11 - Main bias unit;

[0050] 111 - Temperature compensation module;

[0051] 12 - Auxiliary bias unit;

[0052] 121 - Temperature response module;

[0053] vref - Reference voltage terminal;

[0054] vsup - Power supply voltage terminal;

[0055] R0 - Main resistor;

[0056] R1 - First resistor;

[0057] R2 - Second resistor;

[0058] R3 - Third resistor;

[0059] Rout - Output resistor;

[0060] T0 - Power transistor;

[0061] T1 - Auxiliary bias first amplifier;

[0062] T2 - Auxiliary bias second amplifier;

[0063] T3 - Main bias amplifier;

[0064] Q1 - Temperature - responsive triode;

[0065] Q2 - Temperature - compensating first triode;

[0066] Q3 - Temperature - compensating second triode;

[0067] D1 - Temperature - responsive diode;

[0068] D2 - Temperature - compensating first diode;

[0069] D3 - Temperature - compensating second diode;

[0070] C - Capacitor;

[0071] L - Inductor;

[0072] RFin - Radio - frequency signal. Detailed implementation manners

[0073] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0074] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above - mentioned accompanying drawings are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order different from those illustrated or described here. In addition, the terms "include" and "have" and any variations thereof are intended to cover non - exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily limit to those clearly listed steps or units, but may include other steps or units not clearly listed or inherent to these process, method, product or device.

[0075] The technical solution of the present invention will be described in detail below with specific embodiments. The following several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0076] Please refer to Figure 1 , the power amplifier circuit includes a power transistor T0, a main bias unit 11 and an auxiliary bias unit 12;

[0077] The main bias unit 11 is respectively connected to the power supply voltage terminal vsup and the reference voltage terminal vref. The main bias unit 11 is also connected between the control terminal of the power transistor T0 and the first terminal of the power transistor T0, and is used to provide a first bias voltage to the control terminal of the power transistor T0 and the first terminal of the power transistor T0; the first terminal of the power transistor T0 is directly or indirectly connected to the power supply voltage terminal vsup, and the second terminal of the power transistor T0 is grounded;

[0078] The auxiliary bias unit 12 is respectively connected to the power supply voltage terminal vsup and the reference voltage terminal vref. The auxiliary bias unit 12 is also connected between the control terminal of the power transistor T0 and the first terminal of the power transistor T0, and is used to provide a second bias voltage to the power transistor T0 when the current temperature of the auxiliary bias unit 12 is less than the threshold temperature.

[0079] The following describes the specific working process:

[0080] When the power amplifier is just turned on, the temperature of the auxiliary bias unit 12 is relatively low (i.e., less than the threshold temperature). At this time, the main bias unit 11 provides a first bias voltage to the power transistor T0, and the auxiliary bias unit 12 provides a second bias voltage to the power transistor T0, so that the power amplifier quickly reaches the thermal stable state. As the temperature rises, when the temperature rises above the threshold temperature, the auxiliary bias unit 12 no longer provides the second bias voltage to the power transistor T0, and only the first bias voltage provided by the main bias unit 11 is used to keep the power amplifier in the thermal stable state continuously.

[0081] It can be seen that the power amplifier circuit provided by the present invention can simultaneously provide bias voltages to the power transistor through the main bias unit and the auxiliary bias unit when the power transistor is just turned on (the temperature is less than the threshold temperature), thereby helping the power transistor quickly reach the thermal stable state. After the temperature reaches the threshold temperature, only the main bias unit provides the bias voltage to the power transistor to maintain the thermal stable state of the power transistor, and thus the power amplifier can enter the thermal stable state and maintain it in a short time, which helps to improve the linearity of the power amplifier.

[0082] Further, please refer to Figure 2, the auxiliary bias unit 12 includes a temperature response module 121, an auxiliary bias first amplifier T1 and an auxiliary bias second amplifier T2, a first resistor R1, a second resistor R2 and a third resistor R3;

[0083] The first end of the first resistor R1 is connected to the reference voltage terminal vref, the second end of the first resistor R1 is connected to the first end of the temperature response module 121, the second end of the temperature response module 121 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is grounded;

[0084] The control terminal of the auxiliary bias first amplifier T1 is connected between the second end of the temperature response module 121 and the first end of the second resistor R2. The first end of the auxiliary bias first amplifier T1 is connected between the control terminal of the auxiliary bias second amplifier T2 and the first end of the third resistor R3. The second end of the third resistor R3 is connected to the reference voltage terminal vref. The second end of the auxiliary bias first amplifier T1 is grounded. The first end of the auxiliary bias second amplifier T2 is connected to the supply voltage terminal vsup. The control terminal of the auxiliary bias second amplifier T2 is connected to the reference voltage terminal vref through the third resistor R3. The first end of the auxiliary bias second amplifier T2 is directly or indirectly connected to the first end of the power transistor T0. The second end of the auxiliary bias second amplifier T2 is directly or indirectly connected to the control terminal of the power transistor T0;

[0085] The control terminal of the power transistor T0 receives a radio frequency signal RFin; this radio frequency signal RFin can control the operating state of the power amplifier. For example, when the radio frequency signal RFin is in the transmission mode, the power amplifier is turned on, and when the radio frequency signal RFin is not in the transmission mode, the power amplifier is turned off. In other examples, the signal received by the control terminal of the power transistor T0 can also be other input signals.

[0086] The temperature response module 121 is configured to: in response to an increase in the current temperature, reduce the voltage drop across the temperature response module 121, so that: the voltage between the control terminal of the auxiliary bias first amplifier T1 and the second end of the auxiliary bias first amplifier T1 becomes larger;

[0087] Wherein: when the current temperature is greater than the threshold temperature, the voltage between the control terminal of the auxiliary bias first amplifier T1 and the second end of the auxiliary bias first amplifier T1 is higher than the threshold voltage, the auxiliary bias first amplifier T1 is turned on, and the auxiliary bias second amplifier T2 is turned off; at this time, the auxiliary bias unit 12 will no longer provide a second bias voltage to the power transistor T0.

[0088] When the current temperature is less than the threshold temperature, the voltage between the control terminal and the second terminal of the auxiliary bias first amplifier T1 is lower than the threshold voltage, the auxiliary bias first amplifier T1 is turned off, and the auxiliary bias second amplifier T2 is turned on. At this time, the auxiliary bias unit 12 provides a second bias voltage to the power transistor T0.

[0089] Specifically, the temperature response module 121 can be arranged in an area far from the power transistor T0 to avoid the temperature of the temperature response module 121 affecting the power transistor T0.

[0090] Among them, the selection of the first resistor R1 and the second resistor R2 can be adjusted according to the actual circuit. Then, by reasonably selecting the ratio of R1 and R2, the voltage between the control terminal and the second terminal of the auxiliary bias first amplifier T1 can be higher than the threshold voltage when the current temperature is greater than the threshold temperature, so as to turn on the auxiliary bias first amplifier T1 and control the auxiliary bias unit 12 not to provide the second bias voltage to the power transistor.

[0091] Further, please refer to Figure 3a and Figure 3b , the temperature response module 121 includes a temperature response triode Q1; when the temperature of the temperature response triode Q1 rises, the voltage across the temperature response triode Q1 (which can also be understood as: between the collector and the emitter) decreases, and then the voltage across the second resistor R2 increases. At this time, the auxiliary bias first amplifier T2 will be turned on.

[0092] The collector of the temperature response triode Q1 is connected to the second terminal of the first resistor R1, and the emitter of the temperature response triode Q1 is connected to the first terminal of the second resistor R2;

[0093] Please refer to Figure 3a , if the temperature response triode Q1 is an NPN type triode, then: the base of the temperature response triode Q1 is also connected to the collector of the temperature response triode Q1;

[0094] Please refer to Figure 3b , if the temperature response triode Q1 is a PNP type triode, then: the base of the temperature response triode Q1 is also connected to the emitter of the temperature response triode Q1.

[0095] In some solutions, please refer to Figure 3c , the temperature response module 121 further includes a temperature response diode D1. The positive electrode of the temperature response diode D1 is connected to the second terminal of the first resistor R1, and the negative electrode of the temperature response diode D1 is connected to the first terminal of the second resistor R2.

[0096] When the temperature of the temperature-responsive diode D1 increases, the voltage across the two ends of the temperature-responsive diode D1 (which can also be understood as: between the positive electrode and the negative electrode) decreases, thereby increasing the voltage across the second resistor R2. At this time, the auxiliary bias first amplifier T2 will be turned on.

[0097] Further, please refer to Figure 4 , the main bias unit 11 includes a main bias amplifier T3, a main resistor R0, a capacitor C, and a temperature compensation module 111;

[0098] The temperature compensation module 111 is connected between the control terminal of the main bias amplifier T3 and the ground; the temperature compensation module 111 is used to compensate for the offset of the static operating point of the main bias amplifier T3;

[0099] The capacitor C is connected across the two ends of the temperature compensation module 111;

[0100] The first end of the main resistor R0 is connected to the reference voltage terminal vref, and the second end of the main resistor R0 is connected to the first end of the temperature compensation module 111;

[0101] The first end of the main bias amplifier T3 is connected to the supply voltage terminal vsup, and the second end of the main bias amplifier T3 is directly or indirectly connected to the control terminal of the power transistor T0 to provide the first bias voltage to the power transistor T0 when the main bias amplifier T3 is turned on.

[0102] Among them, the temperature compensation module 111 is used to compensate for the offset of the static operating point of the main bias amplifier T3, which can be understood as: the voltage across the temperature compensation module 111 can change with the change of the temperature of the temperature compensation module 111, and thus can adjust the static operating point of the main bias amplifier T3 through the change of the voltage.

[0103] In an example of the working process, when the power amplifier is just turned on, the main bias amplifier T3 is turned on. Since the current temperature at the moment of turning on is less than the threshold temperature, the temperature of the temperature response module 121 (such as the temperature-responsive triode Q1) and the auxiliary bias first amplifier T1 is relatively low. At this time, the auxiliary bias first amplifier T1 is turned off, and the auxiliary bias second amplifier T2 is turned on. Furthermore, the power transistor T0 can be biased by the main bias unit 11 and the auxiliary bias unit 12 at the same time. As the temperature increases, when the temperature of the temperature response module 121 (such as the temperature-responsive triode Q1) and the auxiliary bias first amplifier T1 is greater than the threshold temperature, the auxiliary bias first amplifier T1 remains turned on, and the auxiliary bias second amplifier T2 is turned off. At this time, only the main bias unit 11 biases the power transistor T0, thereby maintaining the power amplifier in a thermally stable state.

[0104] In one embodiment, please refer toFigure 5 , the temperature compensation module 111 includes a first temperature compensation triode Q2 and a second temperature compensation triode Q3;

[0105] The collector of the first temperature compensation triode Q2 is connected to the second end of the main resistor R0, and the collector of the first temperature compensation triode Q2 is also connected to the control end of the main bias amplifier T3;

[0106] The emitter of the first temperature compensation triode Q2 is connected to the collector of the second temperature compensation triode Q3; the base of the first temperature compensation triode Q2 is connected to the collector of the first temperature compensation triode Q2, the emitter of the second temperature compensation triode Q3 is grounded, and the base of the second temperature compensation triode Q3 is connected to the collector of the second temperature compensation triode Q3.

[0107] In some solutions, please refer to Figure 6 , the temperature compensation module 111 includes a first temperature compensation diode D2 and a second temperature compensation diode D3;

[0108] The positive electrode of the first temperature compensation diode D2 is connected to the second end of the main resistor R0, and the positive electrode of the first temperature compensation diode D2 is also connected to the base of the main bias amplifier T3; the negative electrode of the first temperature compensation diode D2 is connected to the positive electrode of the second temperature compensation diode D3, and the negative electrode of the second temperature compensation diode D3 is grounded.

[0109] Please refer to Figure 7 and Figure 8 , further includes an inductor L and an output resistor Rout;

[0110] The inductor L is connected between the first end of the power transistor T0 and the supply voltage terminal vsup, and the output resistor Rout is connected between the auxiliary bias unit 12 and the control end of the power transistor T0.

[0111] The embodiment of the present invention also provides an electronic device, including the power amplifier circuit involved in each of the above embodiments.

[0112] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power amplifier circuit, characterized in that, It includes a power transistor, a main bias unit and an auxiliary bias unit; The main bias unit is respectively connected to the power supply voltage terminal and the reference voltage terminal. The main bias unit is also connected between the control terminal of the power transistor and the first terminal of the power transistor. The main bias unit is used to provide a first bias voltage to the control terminal of the power transistor and the first terminal of the power transistor. The first terminal of the power transistor is directly or indirectly connected to the power supply voltage terminal, and the second terminal of the power transistor is grounded; The auxiliary bias unit is respectively connected to the power supply voltage terminal and the reference voltage terminal. The auxiliary bias unit is also connected between the control terminal of the power transistor and the first terminal of the power transistor. The auxiliary bias unit is used to provide a second bias voltage to the power transistor when the current temperature at which the auxiliary bias unit is located is less than the threshold temperature; The auxiliary bias unit includes a temperature response module, a first auxiliary bias amplifier and a second auxiliary bias amplifier, a first resistor, a second resistor and a third resistor; The first end of the first resistor is connected to the reference voltage terminal, the second end of the first resistor is connected to the first end of the temperature response module, the second end of the temperature response module is connected to the first end of the second resistor, and the second end of the second resistor is grounded; The control terminal of the first auxiliary bias amplifier is connected between the second end of the temperature response module and the first end of the second resistor. The first end of the first auxiliary bias amplifier is connected between the control terminal of the second auxiliary bias amplifier and the first end of the third resistor. The second end of the third resistor is connected to the reference voltage terminal. The second end of the first auxiliary bias amplifier is grounded. The first end of the second auxiliary bias amplifier is connected to the power supply voltage terminal. The control terminal of the second auxiliary bias amplifier is connected to the reference voltage terminal through the third resistor. The first end of the second auxiliary bias amplifier is directly or indirectly connected to the first terminal of the power transistor. The second end of the second auxiliary bias amplifier is directly or indirectly connected to the control terminal of the power transistor; The temperature response module is used for: in response to the increase of the current temperature, reducing the voltage drop across the temperature response module, so that: the voltage between the control terminal of the first auxiliary bias amplifier and the second end of the first auxiliary bias amplifier becomes larger; Wherein: when the current temperature is greater than the threshold temperature, the voltage between the control terminal of the first auxiliary bias amplifier and the second end of the first auxiliary bias amplifier is higher than the threshold voltage, the first auxiliary bias amplifier is turned on, and the second auxiliary bias amplifier is turned off; When the current temperature is less than the threshold temperature, the voltage between the control terminal of the first auxiliary bias amplifier and the second end of the first auxiliary bias amplifier is lower than the threshold voltage, the first auxiliary bias amplifier is turned off, and the second auxiliary bias amplifier is turned on to provide a second bias voltage to the power transistor.

2. The power amplifier circuit according to claim 1, wherein The temperature response module includes a temperature response triode; The collector of the temperature response triode is connected to the second end of the first resistor, and the emitter of the temperature response triode is connected to the first end of the second resistor; If the temperature response triode is an NPN type triode, then: the base of the temperature response triode is also connected to the collector of the temperature response triode; If the temperature response triode is a PNP type triode, then: the base of the temperature response triode is also connected to the emitter of the temperature response triode.

3. The power amplifier circuit according to claim 1, wherein The temperature response module includes a temperature response diode; The positive electrode of the temperature-responsive diode is connected to the second end of the first resistor, and the negative electrode of the temperature-responsive diode is connected to the first end of the second resistor.

4. The power amplifier circuit according to claim 1, characterized in that The main bias unit includes a main bias amplifier, a main resistor, a capacitor, and a temperature compensation module; The temperature compensation module is connected between the control terminal of the main bias amplifier and the ground; the temperature compensation module is used to compensate for the offset of the quiescent operating point of the main bias amplifier; The capacitor is connected across the temperature compensation module; The first end of the main resistor is connected to the reference voltage terminal, and the second end of the main resistor is connected to the first end of the temperature compensation module; The first end of the main bias amplifier is connected to the supply voltage terminal, and the second end of the main bias amplifier is directly or indirectly connected to the control terminal of the power transistor to provide the first bias voltage to the power transistor when the main bias amplifier is turned on.

5. The power amplifier circuit according to claim 4, characterized in that, The temperature compensation module includes a first temperature compensation triode and a second temperature compensation triode; The collector of the first temperature compensation triode is connected to the second end of the main resistor, and the collector of the first temperature compensation triode is also connected to the control terminal of the main bias amplifier; The emitter of the first temperature compensation triode is connected to the collector of the second temperature compensation triode; the base of the first temperature compensation triode is connected to the collector of the first temperature compensation triode, the emitter of the second temperature compensation triode is grounded, and the base of the second temperature compensation triode is connected to the collector of the second temperature compensation triode.

6. The power amplifier circuit according to claim 4, characterized in that The temperature compensation module includes a first temperature compensation diode and a second temperature compensation diode; The positive electrode of the first temperature compensation diode is connected to the second end of the main resistor, and the positive electrode of the first temperature compensation diode is also connected to the base of the main bias amplifier; the negative electrode of the first temperature compensation diode is connected to the positive electrode of the second temperature compensation diode, and the negative electrode of the second temperature compensation diode is grounded.

7. The power amplifier circuit according to claim 1, wherein An inductor and an output resistor are further included; The inductor is connected between the first end of the power transistor and the supply voltage terminal, and the output resistor is connected between the auxiliary bias unit and the control terminal of the power transistor.

8. An electronic device, characterized in that, A power amplifier circuit according to any one of claims 1 to 7 is included.

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