Radio frequency power amplifier protection circuit and radio frequency module

Abstract

The application provides a radio frequency power amplifier protection circuit and a radio frequency module. The circuit relies on a current mirror unit to realize mirror output of a bias current, and is matched with a power protection threshold adjusting unit and a power change rate adjusting unit to independently adjust and control the starting time and the current amplitude of the output bias current. The trigger time and the output bias current size of the protection action can be adaptively adjusted according to the output current detected by the voltage amplitude, the protection logic is flexible and adjustable, the device damage risk caused by power abnormalities can be effectively avoided, and the reliability of the radio frequency power amplifier work is ensured.

Description

Technical Field

[0001] This invention relates to the field of radio frequency power amplifier technology, and particularly to a radio frequency power amplifier protection circuit and radio frequency module. Background Technology

[0002] Radio frequency (RF) power amplifiers are core components of wireless communication transmission links, and their operational stability directly affects the reliability of equipment communication. In practical applications, factors such as load mismatch, signal overdrive, and power fluctuations can easily cause the amplifier's output voltage swing to exceed limits, leading to irreversible damage such as transistor breakdown and burnout. Therefore, power protection circuits are required to protect the device by limiting the output power or adjusting the bias, which is a critical aspect of RF front-end design.

[0003] There is an existing RF power amplifier protection circuit architecture such as Figure 1 As shown, the architecture consists of an output swing detection circuit, an N-type current mirror circuit 1, a P-type current mirror circuit, a configurable resistor network, a feedback amplifier, and an N-type current mirror circuit 2. During operation, the output swing detection circuit acquires the power amplifier's output voltage. When the output swing exceeds a threshold, it triggers the N-type current mirror circuit 1 to generate current. This current is then mirrored and injected into the configurable resistor network to generate a control voltage V1. The control voltage V1 is replicated by the feedback amplifier and drives the N-type current mirror circuit 2 to generate a pull-down current, which is injected into the power amplifier's bias circuit. Power limiting is achieved by pulling down the bias current, and the protection threshold can be configured via the resistor network.

[0004] However, as Figure 1 The existing architecture shown has two significant drawbacks:

[0005] First, the circuit is highly complex, requiring an additional feedback amplifier to achieve voltage replication. This results in a large number of components, consumes a large chip area, and is not conducive to miniaturization and integration. Secondly, it lacks functional flexibility, only supporting the configuration of protection thresholds and unable to adjust the steepness of the pull-down current, meaning it cannot control the rate of change of output power after protection is activated, making it difficult to adapt to the protection response requirements of different application scenarios and limiting its versatility. Summary of the Invention

[0006] This invention provides a radio frequency power amplifier protection circuit and radio frequency module, aiming to solve the problems of high complexity and insufficient functional flexibility of existing power amplifier protection circuits.

[0007] To address the aforementioned technical problems, in a first aspect, the present invention provides a radio frequency power amplifier protection circuit, comprising a current mirror unit, a power protection threshold adjustment unit, and a power change rate adjustment unit, wherein: The first end of the current mirror unit serves as the first input terminal of the RF power amplifier protection circuit, used to connect to the power supply voltage. The second end of the current mirror unit serves as the second input terminal of the RF power amplifier protection circuit, used to connect to the voltage amplitude detection output current of the RF power amplifier. The third end of the current mirror unit is used to connect to the power protection threshold adjustment unit and the power change rate adjustment unit respectively. The fourth end of the current mirror unit serves as the output terminal of the RF power amplifier protection circuit, used to output bias current to the bias circuit of the RF power amplifier. The power protection threshold adjustment unit is used to control the on-time of the current mirror unit outputting the bias current; The power change rate adjustment unit is used to control the magnitude of the bias current output by the current mirror unit.

[0008] Furthermore, the current mirror unit includes a first resistor, a first transistor, a second transistor, a third transistor, and a fourth transistor, wherein: The first end of the first resistor serves as the second end of the current mirror unit, which is used to connect to the voltage amplitude detection output current. The second end of the first resistor is connected to the drain of the third transistor. The source of the first transistor serves as the first terminal of the current mirror unit, the drain of the first transistor is connected to the source of the third transistor, the gate of the first transistor is connected to the gate of the second transistor, and the gate of the first transistor is connected to the drain of the first transistor. The source of the second transistor is connected to the source of the first transistor, and the drain of the second transistor is connected to the source of the fourth transistor, wherein the drain of the second transistor serves as the third terminal of the current mirror unit. The gate of the third transistor is connected to the gate of the fourth transistor, and the gate of the third transistor is connected to the drain of the third transistor. The drain of the fourth transistor serves as the fourth terminal of the current mirror unit.

[0009] Furthermore, the power protection threshold adjustment unit includes a current source, a fifth transistor, a sixth transistor, and multiple current mirror units. Each current mirror unit includes a common-source transistor, a common-gate transistor, and a threshold control switch, wherein: The input terminal of the current source is used to connect to the power supply voltage; The drain of the fifth transistor is connected to the output terminal of the current source, the source of the fifth transistor is connected to the drain of the sixth transistor, the gate of the fifth transistor is connected to the gate of each of the common source transistors, and the gate of the fifth transistor is connected to the drain of the fifth transistor. The source of the sixth transistor is grounded, the gate of the sixth transistor is connected to the gate of each of the common gate transistors, and the gate of the sixth transistor is connected to the drain of the sixth transistor. The threshold control switch is a single-pole single-throw switch. In the current mirror unit, the source of the common-source transistor is connected to the drain of the common-gate transistor, and the drain of the common-source transistor is connected to the second terminal of the threshold control switch. The source of the common-gate transistor is grounded. The first terminal of the threshold control switch is connected to the third terminal of the current mirror unit.

[0010] Furthermore, the power change rate regulation unit includes a seventh transistor and a plurality of resistor regulation subunits connected in series. Each resistor regulation subunit includes a fixed resistor and a rate regulation switch connected in parallel with the fixed resistor, wherein: Multiple fixed resistors are connected in series, with the first end of the first fixed resistor connected to the third end of the current mirror unit, and the second end of the last fixed resistor connected to the source of the seventh transistor; the rate adjustment switch is a single-pole single-throw switch. The gate of the seventh transistor is connected to the second terminal of the current mirror unit, and the drain of the seventh transistor is grounded.

[0011] Furthermore, the on-time of the bias current output by the current mirror unit is adjusted by controlling the number of threshold control switches turned on in the power protection threshold adjustment unit. The more threshold control switches turned on, the later the on-time of the bias current output by the current mirror unit is.

[0012] Furthermore, the magnitude of the bias current output by the current mirror unit is adjusted by controlling the number of rate adjustment switches turned on in the power change rate adjustment unit. The more rate adjustment switches turned on, the smaller the bias current output by the current mirror unit.

[0013] Secondly, the present invention also provides a radio frequency module, the radio frequency module including the radio frequency power amplifier protection circuit as described above.

[0014] The beneficial effect achieved by this invention lies in proposing a protection circuit for an RF power amplifier. This circuit relies on a current mirror unit to realize the mirror output of the bias current. With the help of a power protection threshold adjustment unit and a power change rate adjustment unit, the start time and current amplitude of the output bias current can be independently controlled. Based on the output current obtained by voltage amplitude detection, the trigger time of the protection action and the magnitude of the output bias current can be adaptively adjusted. The protection logic is flexible and adjustable, which can effectively avoid the risk of device damage caused by power abnormalities and ensure the reliability of the RF power amplifier. Attached Figure Description

[0015] The present invention will now be described in detail with reference to the accompanying drawings. The above and other aspects of the present invention will become clearer and more readily understood through the detailed description following the accompanying drawings. In the drawings: Figure 1 This is a block diagram of an existing RF power amplifier protection circuit; Figure 2 This is a structural block diagram of the radio frequency power amplifier protection circuit provided in an embodiment of the present invention; Figure 3 This is a circuit diagram of the radio frequency power amplifier protection circuit provided in an embodiment of the present invention. Detailed Implementation

[0016] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0017] The specific embodiments / examples described herein are specific implementations of the present invention, used to illustrate the concept of the invention, and are illustrative and exemplary, and should not be construed as limiting the implementation methods or scope of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein, all of which are within the protection scope of the present invention.

[0018] Example 1 Please refer to Figure 2 , Figure 2 This is a schematic diagram of a radio frequency power amplifier protection circuit provided in an embodiment of the present invention. The radio frequency power amplifier protection circuit 100 includes a current mirror unit 101, a power protection threshold adjustment unit 102, and a power change rate adjustment unit 103, wherein: The first end of the current mirror unit 101 serves as the first input terminal of the RF power amplifier protection circuit 100, and is used to connect to the power supply voltage VDD. The second end of the current mirror unit 101 serves as the second input terminal of the RF power amplifier protection circuit 100, and is used to connect to the voltage amplitude detection output current of the RF power amplifier. The third end of the current mirror unit 101 is used to connect to the power protection threshold adjustment unit 102 and the power change rate adjustment unit 103 respectively. The fourth end of the current mirror unit 101 serves as the output terminal of the RF power amplifier protection circuit 100, and is used to output a bias current to the bias circuit of the RF power amplifier. The power protection threshold adjustment unit 102 is used to control the start time of the current mirror unit 101 outputting the bias current; The power change rate adjustment unit 103 is used to control the magnitude of the bias current output by the current mirror unit 101.

[0019] For details, please refer to Figure 3 The circuit diagram shown in this embodiment of the invention includes a first resistor R1, a first transistor M1, a second transistor M2, a third transistor M3, and a fourth transistor M4, wherein: The first end of the first resistor R1 serves as the second end of the current mirror unit 101, which is used to connect to the voltage amplitude detection output current. The second end of the first resistor R1 is connected to the drain of the third transistor M3. The source of the first transistor M1 serves as the first terminal of the current mirror unit 101. The drain of the first transistor M1 is connected to the source of the third transistor M3. The gate of the first transistor M1 is connected to the gate of the second transistor M2, and the gate of the first transistor M1 is connected to the drain of the first transistor M1. The source of the second transistor M2 is connected to the source of the first transistor M1, and the drain of the second transistor M2 is connected to the source of the fourth transistor M4, wherein the drain of the second transistor M2 serves as the third terminal of the current mirror unit 101. The gate of the third transistor M3 is connected to the gate of the fourth transistor M4, and the gate of the third transistor M3 is connected to the drain of the third transistor M3. The drain of the fourth transistor M4 serves as the fourth terminal of the current mirror unit 101.

[0020] The power protection threshold adjustment unit 102 includes a current source, a fifth transistor M5, a sixth transistor M6, and multiple current mirror units 1021. Each current mirror unit 1021 includes a common-source transistor Mi, a common-gate transistor Mo, and a threshold control switch Se, wherein: The input terminal of the current source is used to connect to the power supply voltage VDD; The drain of the fifth transistor M5 is connected to the output terminal of the current source, the source of the fifth transistor M5 is connected to the drain of the sixth transistor M6, the gate of the fifth transistor M5 is connected to the gate of each of the common source transistors Mi, and the gate of the fifth transistor M5 is connected to the drain of the fifth transistor M5. The source of the sixth transistor M6 is grounded, the gate of the sixth transistor M6 is connected to the gate of each of the common gate transistors Mo, and the gate of the sixth transistor M6 is connected to the drain of the sixth transistor M6. The threshold control switch Se is a single-pole single-throw switch. In the current mirror unit 1021, the source of the common-source transistor Mi is connected to the drain of the common-gate transistor Mo, and the drain of the common-source transistor Mi is connected to the second terminal of the threshold control switch Se. The source of the common-gate transistor Mo is grounded. The first terminal of the threshold control switch Se is connected to the third terminal of the current mirror unit 101.

[0021] Based on the circuit structure of the power protection threshold adjustment unit 102 described in the above embodiments, its circuit elements constitute an N-type current mirror structure, including a basic common-source current mirror, a common-source cascode current mirror, and a low-voltage common-source cascode structure current mirror.

[0022] The power change rate regulation unit 103 includes a seventh transistor M7 and a plurality of resistor regulation subunits 1031 connected in series. Each resistor regulation subunit 1031 includes a fixed resistor Rn and a rate regulation switch Sn connected in parallel with the fixed resistor Rn, wherein: Multiple fixed resistors Rn are connected in series. The first end of the first fixed resistor Rn is connected to the third end of the current mirror unit 101, and the second end of the last fixed resistor Rn is connected to the source of the seventh transistor M7. The rate adjustment switch Sn is a single-pole single-throw switch, and the first and second ends of the rate adjustment switch Sn are respectively connected to the first and second ends of the corresponding fixed resistors Rn. The gate of the seventh transistor M7 is connected to the second terminal of the current mirror unit 101, and the drain of the seventh transistor M7 is grounded.

[0023] The following explains the working principle of the RF power amplifier protection circuit 100 proposed in this embodiment of the invention to achieve dynamic adjustment of the power amplifier bias. Please refer to... Figure 3 In this embodiment of the invention, the on-time of the bias current output by the current mirror unit 101 is adjusted by controlling the number of threshold control switches Se turned on in the power protection threshold adjustment unit 102. The more threshold control switches Se turned on, the later the on-time of the bias current output by the current mirror unit 101 is as the voltage amplitude detection output current gradually increases.

[0024] Specifically, in the power protection threshold adjustment unit 102 of this embodiment, the fifth transistor M5 and the sixth transistor M6 are both connected in a diode configuration with their gates and drains shorted. They are connected in series between the power supply terminal and the ground terminal, and can output stable gate reference potentials respectively. The gate potential of the fifth transistor M5 is uniformly applied to the gates of all common-source transistors Mi, and the gate potential of the sixth transistor M6 is uniformly applied to the gates of all common-gate transistors Mo, so that each group of common-source transistors Mi and common-gate transistors Mo is given a fixed bias and is in a ready-to-conduct state.

[0025] Each current mirror unit 1021 is connected in parallel to form multiple independent conducting branches. Within a single branch, the source of the common-source transistor Mi is connected to the drain of the common-gate transistor Mo, the source of the common-gate transistor Mo is connected to ground, and the drain of the common-source transistor Mi is connected to the second terminal of the current mirror unit 101 via a threshold control switch Se. Therefore, when a single threshold control switch Se is turned on, the corresponding current mirror unit 1021 branch is fully connected to the circuit, forming a conducting path from the second terminal of the current mirror unit 101 to the ground terminal; when the threshold control switch Se is turned off, the corresponding branch is in a floating state and no current flows.

[0026] The bias current output of the current mirror unit 101 is determined by the potential at the second terminal of the current mirror unit 101 reaching a preset trigger level. During system operation, the voltage amplitude detection output current of the RF power amplifier gradually increases and continuously drives the potential at the second terminal of the current mirror unit 101, causing the potential at that point to approach the trigger level. However, the conducting branches of the current mirror units 1021 will clamp the potential and discharge the current at the second terminal of the current mirror unit 101, directly preventing its potential from quickly reaching the trigger condition.

[0027] As the number of activated threshold control switches Se increases, the number of parallel conducting branches connected to the second terminal of the current mirror unit 101 also increases, and the overall equivalent discharge capability and potential clamping strength are simultaneously improved. At this time, relying solely on a small increase in voltage amplitude to detect the output current is insufficient to overcome the clamping effect of multiple parallel branches, and the potential at the second terminal of the current mirror unit 101 is difficult to quickly reach the trigger level; it is necessary to wait for the voltage amplitude to detect the output current to continue to rise and provide stronger driving capability before the triggering condition can be finally met, allowing the current mirror unit 101 to start outputting bias current. Therefore, the start time of the output bias current will be gradually delayed.

[0028] Conversely, if the number of conducting threshold control switches Se is small and the number of parallel conducting branches is small, the clamping and discharging effect on the second terminal of the current mirror unit 101 is weak. The voltage amplitude detection output current only needs to increase slightly to push the potential of the point to the trigger level, and the current mirror unit 101 will output the bias current earlier.

[0029] In summary, during implementation, a certain number of current mirror units 1021 can be set in the circuit as needed. By changing the conduction threshold to control the number of switches Se, the total load intensity of the parallel branches can be flexibly adjusted, thereby changing the opening time of the bias current output by the current mirror unit 101, and ultimately achieving controllable adjustment of the protection action timing.

[0030] Furthermore, the magnitude of the bias current output by the current mirror unit 101 is adjusted by controlling the number of rate adjustment switches Sn turned on in the power change rate adjustment unit 103. The more rate adjustment switches Sn turned on, the smaller the bias current output by the current mirror unit 101.

[0031] In this embodiment of the invention, the power change rate adjustment unit 103 consists of a seventh transistor M7 and multiple sets of resistor adjustment subunits 1031 forming an overall load branch. A series resistor network is connected between the second end of the current mirror unit 101 and the source of the seventh transistor M7. The gate of the seventh transistor M7 is connected to the voltage amplitude detection output current, and the drain is connected to the ground terminal, forming a complete current discharge path.

[0032] For the seventh transistor M7, its gate is controlled by the voltage amplitude detection output current. The magnitude of the detection current will change the conduction degree and equivalent conduction impedance of the seventh transistor M7, so that a controllable and stable discharge channel is formed from the source of the seventh transistor M7 to the ground terminal. The overall working state of the series resistor network is jointly determined by the potential of the second terminal of the current mirror unit 101 and the potential of the source of the seventh transistor M7.

[0033] For the resistance regulation subunit 1031, multiple fixed resistors Rn are connected end to end in sequence to form a series resistance trunk circuit. Each fixed resistor Rn is connected in parallel with a speed regulation switch Sn. When a speed regulation switch Sn is turned on, it will directly bypass and short-circuit the fixed resistor Rn connected in parallel, and the fixed resistor Rn will no longer participate in the voltage division and current limiting of the circuit. When the speed regulation switch Sn is turned off, the corresponding fixed resistor Rn remains in the series circuit and functions normally.

[0034] In this topology, the number of conducting rate control switches Sn directly determines the total equivalent resistance of the series circuit: the more conducting rate control switches Sn there are, the more fixed resistors Rn are bypassed and short-circuited, and the smaller the total equivalent resistance of the entire series resistor network; conversely, the fewer conducting rate control switches Sn there are, the more fixed resistors Rn are connected to the series circuit, and the larger the total equivalent resistance of the circuit.

[0035] The second terminal of the current mirror unit 101 is a common node. The total current output from this node is divided into two parts: one part serves as the final external bias current, which is supplied to the bias circuit of the RF power amplifier; the other part flows into the series resistor network of this power change rate adjustment unit 103 and is discharged to the ground terminal via the seventh transistor M7. According to the circuit current shunting principle, under the premise that the overall driving capability of the current mirror unit 101 remains basically unchanged, the smaller the total equivalent resistance of the series resistor network, the stronger the current shunting capability of this branch, and the more current is drawn from the second terminal of the current mirror unit 101.

[0036] When the number of conducting rate regulating switches Sn increases, the total equivalent resistance of the series circuit decreases, the shunt current of the power change rate regulating unit 103 branch increases significantly, crowding out the output current of the second terminal of the current mirror unit 101, and ultimately reducing the amplitude of the bias current output by the current mirror unit 101.

[0037] In summary, during implementation, a certain number of resistor adjustment subunits 1031 can be set in the circuit as needed. By changing the conduction rate and adjusting the number of switches Sn, the total equivalent impedance of the series resistor network can be continuously adjusted, the branch current shunting magnitude can be changed, and the magnitude of the bias current output by the current mirror unit 101 can be precisely controlled, thereby realizing the level adjustment of the bias current amplitude.

[0038] The beneficial effect achieved by this invention lies in proposing a protection circuit for an RF power amplifier. This circuit relies on a current mirror unit to realize the mirror output of the bias current. With the help of a power protection threshold adjustment unit and a power change rate adjustment unit, the start time and current amplitude of the output bias current can be independently controlled. The circuit can output current according to the voltage amplitude, adaptively adjust the trigger time of the protection action and the magnitude of the output bias current. The protection logic is flexible and adjustable, which can effectively avoid the risk of device damage caused by power abnormalities and ensure the reliability of the RF power amplifier.

[0039] Example 2 This invention also provides an RF module, wherein the RF chip includes the RF power amplifier protection circuit 100 described in Embodiment 1 above. It is understood that, based on the specific circuit design of the RF power amplifier protection circuit 100, the RF module can achieve a mirrored output of the bias current using a current mirror unit. Combined with a power protection threshold adjustment unit and a power change rate adjustment unit, the activation time and current amplitude of the output bias current can be independently controlled. The output current can be adjusted according to the voltage amplitude, adaptively adjusting the trigger time of the protection action and the magnitude of the output bias current. The protection logic is flexible and adjustable, effectively avoiding the risk of device damage caused by power anomalies and ensuring the reliability of the RF power amplifier. Referring to the description in the above embodiments, further details are omitted here.

[0040] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0041] The embodiments of the present invention have been described above with reference to the accompanying drawings. The disclosed embodiments are merely preferred embodiments of the present invention. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many equivalent changes in form under the guidance of the present invention without departing from the spirit and scope of the claims. All such changes are within the protection scope of the present invention.

Claims

1. A protection circuit for a radio frequency power amplifier, characterized in that, It includes a current mirror unit, a power protection threshold adjustment unit, and a power change rate adjustment unit, wherein: The first end of the current mirror unit serves as the first input terminal of the RF power amplifier protection circuit, used to connect to the power supply voltage. The second end of the current mirror unit serves as the second input terminal of the RF power amplifier protection circuit, used to connect to the voltage amplitude detection output current of the RF power amplifier. The third end of the current mirror unit is used to connect to the power protection threshold adjustment unit and the power change rate adjustment unit respectively. The fourth end of the current mirror unit serves as the output terminal of the RF power amplifier protection circuit, used to output bias current to the bias circuit of the RF power amplifier. The power protection threshold adjustment unit is used to control the on-time of the current mirror unit outputting the bias current; The power change rate adjustment unit is used to control the magnitude of the bias current output by the current mirror unit; The current mirror unit includes a first resistor, a first transistor, a second transistor, a third transistor, and a fourth transistor, wherein: The first end of the first resistor serves as the second end of the current mirror unit, which is used to connect to the voltage amplitude detection output current. The second end of the first resistor is connected to the drain of the third transistor. The source of the first transistor serves as the first terminal of the current mirror unit, the drain of the first transistor is connected to the source of the third transistor, the gate of the first transistor is connected to the gate of the second transistor, and the gate of the first transistor is connected to the drain of the first transistor. The source of the second transistor is connected to the source of the first transistor, and the drain of the second transistor is connected to the source of the fourth transistor, wherein the drain of the second transistor serves as the third terminal of the current mirror unit. The gate of the third transistor is connected to the gate of the fourth transistor, and the gate of the third transistor is connected to the drain of the third transistor. The drain of the fourth transistor serves as the fourth terminal of the current mirror unit.

2. The RF power amplifier protection circuit according to claim 1, characterized in that, The power protection threshold adjustment unit includes a current source, a fifth transistor, a sixth transistor, and multiple current mirror units. Each current mirror unit includes a common-source transistor, a common-gate transistor, and a threshold control switch, wherein: The input terminal of the current source is used to connect to the power supply voltage; The drain of the fifth transistor is connected to the output terminal of the current source, the source of the fifth transistor is connected to the drain of the sixth transistor, the gate of the fifth transistor is connected to the gate of each of the common source transistors, and the gate of the fifth transistor is connected to the drain of the fifth transistor. The source of the sixth transistor is grounded, the gate of the sixth transistor is connected to the gate of each of the common gate transistors, and the gate of the sixth transistor is connected to the drain of the sixth transistor. The threshold control switch is a single-pole single-throw switch. In the current mirror unit, the source of the common-source transistor is connected to the drain of the common-gate transistor, and the drain of the common-source transistor is connected to the second terminal of the threshold control switch. The source of the common-gate transistor is grounded. The first terminal of the threshold control switch is connected to the third terminal of the current mirror unit.

3. The RF power amplifier protection circuit according to claim 1, characterized in that, The power change rate regulation unit includes a seventh transistor and multiple resistor regulation subunits connected in series. Each resistor regulation subunit includes a fixed resistor and a rate regulation switch connected in parallel with the fixed resistor, wherein: Multiple fixed resistors are connected in series, with the first end of the first fixed resistor connected to the third end of the current mirror unit, and the second end of the last fixed resistor connected to the source of the seventh transistor; the rate adjustment switch is a single-pole single-throw switch. The gate of the seventh transistor is connected to the second terminal of the current mirror unit, and the drain of the seventh transistor is grounded.

4. The RF power amplifier protection circuit according to claim 2, characterized in that, The on-time of the bias current output by the current mirror unit is adjusted by controlling the number of threshold control switches turned on in the power protection threshold adjustment unit. The more threshold control switches turned on, the later the on-time of the bias current output by the current mirror unit is as the voltage amplitude detection output current gradually increases.

5. The RF power amplifier protection circuit according to claim 3, characterized in that, The magnitude of the bias current output by the current mirror unit is adjusted by controlling the number of rate adjustment switches turned on in the power change rate adjustment unit. The more rate adjustment switches turned on, the smaller the bias current output by the current mirror unit.

6. A radio frequency module, characterized in that, The radio frequency module includes the radio frequency power amplifier protection circuit as described in any one of claims 1 to 5.

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