A power amplifier control circuit and radio frequency device

Abstract

The present application discloses a power amplifier control circuit and a radio frequency device, which are applied to the field of amplifier control technology to solve the problem in the prior art that the circuit structure and control logic of the power amplifier control circuit for realizing power control and gain control are relatively complex. Specifically: the mode switching module is used to determine the current control mode according to the mode selection signal. In the gain control mode, the first voltage is used as the attenuation voltage. In the power control mode, the power control module determines the second voltage that meets the power requirement according to the first voltage. The mode switching module uses the second voltage as the attenuation voltage. The attenuation module is used to adjust the attenuation amount of the radio frequency signal according to the attenuation voltage. The power amplifier module performs power amplification on the adjusted radio frequency signal. In this way, the mode switching module determines the working mode according to the mode selection signal and determines the attenuation voltage for power control or gain control, thereby simplifying the circuit structure and control logic.

Description

Technical Field

[0001] The present application relates to the field of amplifier control technology, and in particular to a power amplifier control circuit and a radio frequency device. Background Art

[0002] In communication systems, power amplifiers are important components that are mainly used to amplify radio frequency signals. By setting a control circuit for the power amplifier, the amplification effect of the power amplifier can be controlled so that the amplification effect of the amplifier meets different application requirements.

[0003] At present, the control of the amplification effect of power amplifiers is mainly divided into power control and gain control. Power control is to control the power amplifier so that the RF signal output by the power amplifier is stabilized at the same power value when the RF signal input power is within a preset range. Gain control is to control the gain value of the power amplifier. Existing power amplifier control circuits often set up gain control circuits and power control circuits separately, and control the corresponding control circuits through two control signals to achieve power control and gain control of the power amplifier. However, the structure of this power amplifier control circuit is relatively complex, the number of devices included is large, and the space occupied is large. In addition, this power amplifier control circuit requires two analog input control signals. In order to avoid the influence of the two control modes, its control logic is relatively complex. Summary of the Invention

[0004] The embodiments of the present application provide a power amplifier control circuit and a radio frequency device to solve the problem in the prior art that the circuit structure and control logic of the power amplifier control circuit for implementing power control and gain control are relatively complex.

[0005] The technical solutions provided in the embodiments of this application are as follows:

[0006] On the one hand, an embodiment of the present application provides a power amplifier control circuit, including: a mode switching module, a power control module, an attenuation module, and a power amplifier module;

[0007] The first end of the mode switching module is connected to the external controller, the second end of the mode switching module is connected to the first end of the power control module, and the third end of the mode switching module is connected to the first end of the attenuation module; the mode switching module is used to determine the current control mode according to the mode selection signal input by the external controller, and in the gain control mode, transmit the first voltage input by the external controller to the attenuation module as the attenuation voltage; in the power control mode, transmit the first voltage input by the external controller to the power control module, and transmit the second voltage returned by the power control module to the attenuation module as the attenuation voltage;

[0008] The power control module is used to determine a second voltage that meets the power requirement according to the first voltage in the power control mode, and transmit the second voltage to the mode switching module;

[0009] The second end of the attenuation module is connected to the external RF signal generating device, and the third end of the attenuation module is connected to the first end of the power amplifier module; the attenuation module is used to adjust the attenuation of the RF signal input by the external RF signal generating device according to the attenuation voltage;

[0010] The power amplifier module is used to amplify the power of the radio frequency signal output by the attenuation module to obtain the target radio frequency signal.

[0011] In one possible implementation, the mode switching module includes: two switches controlled by a mode selection signal;

[0012] A common terminal of the first switch of the two switches is connected to an external controller, a first terminal of the first switch of the two switches is connected to a first terminal of the second switch of the two switches, and a second terminal of the first switch of the two switches is connected to a first terminal of a power control module;

[0013] A common terminal of the second switch of the two switches is connected to the first terminal of the attenuation module, and a second connection terminal of the second switch of the two switches is connected to the second terminal of the power control module.

[0014] In a possible implementation manner, the power amplifier control circuit further includes: a detection module;

[0015] The first end of the detection module is connected to the third end of the power control module, the second end of the detection module is connected to the second end of the power amplifier module, and the third end of the detection module serves as the output end of the target RF signal; the detection module is used to determine the detection voltage of the RF signal output by the power amplifier module.

[0016] In one possible implementation, the power control module includes: three resistors, a capacitor, and two operational amplifiers;

[0017] A positive input terminal of a first operational amplifier among the two operational amplifiers is connected to a first terminal of the detection module, a negative input terminal of the first operational amplifier among the two operational amplifiers is connected to an output terminal of the first operational amplifier among the two operational amplifiers via a first resistor among the three resistors, and the output terminal of the first operational amplifier among the two operational amplifiers is connected to a first terminal of a second resistor among the three resistors;

[0018] A positive input terminal of the second operational amplifier among the two operational amplifiers is connected to the second terminal of the mode switching module via a third resistor among the three resistors, a negative input terminal of the second operational amplifier among the two operational amplifiers is connected to the second terminal of the second resistor among the three resistors, and an output terminal of the second operational amplifier among the two operational amplifiers is connected to the fourth terminal of the mode switching module;

[0019] A first end of the capacitor is connected to a second end of a second resistor among the three resistors, and a second end of the capacitor is connected to an output end of a second operational amplifier among the two operational amplifiers.

[0020] In a possible implementation, the power amplifier control circuit further includes: a voltage regulation module;

[0021] The first end of the voltage regulating module is connected to the external controller, and the second end of the voltage regulating module is connected to the first end of the mode switching module; the voltage regulating module is used to adjust the magnitude of the first voltage when the mode selection signal changes.

[0022] In a possible implementation, the attenuation module includes: an attenuator.

[0023] In one possible implementation, the attenuator is a positive slope analog attenuator or a negative slope analog attenuator.

[0024] In a possible implementation, the detection module includes: a radio frequency detector.

[0025] In a possible implementation, the power amplifier module includes: a radio frequency power amplifier.

[0026] On the other hand, an embodiment of the present application provides a radio frequency device, including: a power amplifier control circuit, a controller, a radio frequency signal receiving device, and a radio frequency signal sending device provided in an embodiment of the present application; the controller is connected to the first end of the power amplifier control circuit, the radio frequency signal receiving device is connected to the second end of the power amplifier control circuit, and the radio frequency signal receiving device is connected to the third end of the power amplifier control circuit.

[0027] The beneficial effects of the embodiments of the present application are as follows:

[0028] In an embodiment of the present application, the mode switching module determines whether the current control mode is a gain control mode or a power control mode according to a mode selection signal input by an external controller. In the gain control mode, the external first voltage is directly used as the attenuation voltage to implement gain control of the power amplifier module through the attenuation module. In the power control mode, the power control module determines a second voltage that meets the power requirement based on the first voltage, and the mode switching module uses the second voltage as the attenuation voltage to implement power control of the power amplifier module through the attenuation module. Only the mode selection signal and the first voltage are required to implement gain control and power control of the power amplifier module. The control signals are relatively few and the control logic is simple. Moreover, by inputting the second voltage determined based on the first voltage as the attenuation voltage into the attenuation module by the power control module, the attenuation module can be reused in the power control process. The attenuation module can implement power control and gain control, simplify the circuit structure, and reduce the number of components in the circuit.

[0029] Other features and advantages of the present application will be described in the following description, and in part will become apparent from the description or be understood by practicing the present application. The purposes and other advantages of the present application can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0031] Figure 1 This is a schematic diagram of a first circuit structure of a power amplifier control circuit in an embodiment of the present application;

[0032] Figure 2 This is a schematic diagram of a second circuit structure of the power amplifier control circuit in an embodiment of the present application;

[0033] Figure 3 This is a schematic diagram of a third circuit structure of the power amplifier control circuit in an embodiment of the present application;

[0034] Figure 4 This is a fourth circuit structure diagram of the power amplifier control circuit in the embodiment of the present application;

[0035] Figure 5 Schematic diagram of a fifth circuit structure of the power amplifier control circuit in an embodiment of the present application;

[0036] Figure 6 This is a schematic diagram of slope matching in an embodiment of the present application;

[0037] Figure 7Schematic diagram of a sixth circuit structure of the power amplifier control circuit in an embodiment of the present application;

[0038] Figure 8 Schematic diagram of the seventh circuit structure of the power amplifier control circuit in the embodiment of the present application;

[0039] Figure 9 Schematic diagram of an eighth circuit structure of the power amplifier control circuit in an embodiment of the present application;

[0040] Figure 10 This is a schematic diagram of the internal structure of a dual-channel analog switch in an embodiment of the present application;

[0041] Figure 11 Schematic diagram of the relationship between voltage and attenuation of the reverse slope analog attenuator in an embodiment of the present application;

[0042] Figure 12 Schematic diagram of the relationship between the output voltage and input power of the logarithmic linear radio frequency detector in an embodiment of the present application;

[0043] Figure 13 This is a schematic diagram of the first circuit structure of the radio frequency device in an embodiment of the present application. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and beneficial effects of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0045] It should be noted that the terms "first," "second," etc., mentioned in this application are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that such terms are interchangeable where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0046] In order to solve the problem that the circuit structure and control logic of the power amplifier control circuit for realizing power control and gain control in the prior art are relatively complex, the embodiment of the present application provides a power amplifier control circuit, see Figure 1 As shown, the power amplifier control circuit 100 provided in the embodiment of the present application includes at least: a mode switching module 110, a power control module 120, an attenuation module 130, and a power amplifier module 140;

[0047] A first end of the mode switching module 110 is connected to the external controller, a second end of the mode switching module 110 is connected to the first end of the power control module 120, and a third end of the mode switching module 110 is connected to the first end of the attenuation module 130. The mode switching module 110 is configured to determine a current control mode according to a mode selection signal input by the external controller. In a gain control mode, the first voltage input by the external controller is transmitted to the attenuation module 130 as an attenuation voltage. In a power control mode, the first voltage input by the external controller is transmitted to the power control module 120, and a second voltage returned by the power control module 120 is transmitted to the attenuation module 130 as an attenuation voltage.

[0048] The power control module 120 is configured to determine a second voltage that meets the power requirement according to the first voltage in the power control mode, and transmit the second voltage to the mode switching module 110;

[0049] The second end of the attenuation module 130 is connected to the external RF signal generating device, and the third end of the attenuation module 130 is connected to the first end of the power amplifier module 140; the attenuation module 130 is used to adjust the attenuation of the RF signal input by the external RF signal generating device according to the attenuation voltage;

[0050] The power amplifier module 140 is used to amplify the power of the radio frequency signal output by the attenuation module 130 to obtain a target radio frequency signal.

[0051] In actual applications, the power amplifier control circuit 100 has two control modes, namely, a gain control mode and a power control mode. Based on actual working requirements, an external controller generates a mode selection signal and inputs it into the mode switching module 110 of the power amplifier control circuit 100, wherein the mode selection signal is generally a digital signal. For example, the mode selection signal can be set to 0 to indicate a gain control mode, and the mode selection signal can be set to 1 to indicate a power control mode. The mode switching module 110 determines the current control mode according to the input mode selection signal. If the current control mode is the gain control mode, the mode switching module 110 inputs the first voltage input by the external controller as the attenuation voltage to the attenuation module 130. The attenuation module 130 adjusts the attenuation of the RF signal input to the power amplifier module 140 according to the attenuation voltage, and transmits the adjusted RF signal input signal to the power amplifier module 140, so that the power amplifier module 140 performs power amplification on the RF signal output by the attenuation module 130 to obtain the target RF signal, thereby directly controlling the gain of the target RF signal output by the power amplifier module 140 through the first voltage input by the external controller. If the current control mode is the power control mode, the mode switching module 110 transmits the first voltage input by the external controller to the power control module 120. The power module determines the second voltage that meets the current power requirement based on the first voltage input by the external controller and the voltage of the current RF signal, wherein the power requirement refers to the target power corresponding to the first voltage, and returns the second voltage to the mode switching module 110. The mode switching module 110 inputs the second voltage as the attenuation voltage to the attenuation module 130. The attenuation module 130 adjusts the attenuation amount of the RF signal input to the power amplifier module 140 according to the attenuation voltage, and transmits the adjusted RF signal input signal to the power amplifier module 140, so that the power amplifier module 140 amplifies the RF signal output by the attenuation module 130 to obtain the target RF signal, thereby stabilizing the power of the target RF signal output by the power amplifier module 140 to the target power corresponding to the first voltage input by the external controller.

[0052] In specific implementations, in gain control mode, the externally input first voltage corresponds to the gain adjustment amplitude. By directly using the input first voltage as the attenuation voltage for adjusting the attenuation, the attenuation of the RF signal input to the power amplifier module 140 is adjusted based on the attenuation voltage, thereby achieving gain control of the power amplifier module 140. By changing the first voltage, the target RF signal can be adjusted to the corresponding gain. In power control mode, the externally input first voltage corresponds to the target power for power adjustment. By changing the first voltage, the target RF signal can be adjusted to the corresponding power. The second voltage refers to the voltage corresponding to the attenuation required to adjust the power of the target RF signal to the target power corresponding to the first voltage. The power control module 120 determines the voltage corresponding to the attenuation required to meet the power requirement based on the first voltage corresponding to the target power and the current voltage of the RF signal. The target power for power control is converted to the attenuation required to achieve the target power, i.e., the second voltage is determined. The attenuation module 130 adjusts the gain of the RF signal input to the power amplifier module 140 based on the attenuation voltage formed by the second voltage, thereby achieving power control of the power amplifier module 140. In this way, the mode switching module 110 determines whether the current control mode is the gain control mode or the power control mode based on the mode selection signal input by the external controller. In the gain control mode, the external first voltage is directly used as the attenuation voltage to implement gain control of the power amplifier module 140 through the attenuation module 130. In the power control mode, the power control module 120 determines a second voltage that meets the power requirement based on the first voltage, and uses the first voltage as the attenuation voltage to implement power control of the power amplifier module 140 through the attenuation module 130. Compared with the traditional power amplifier control circuit 100, it only requires the mode selection signal and the first voltage to implement gain control and power control of the power amplifier module 140. It has fewer control signals and simpler logic, and does not need to consider the mutual influence between the two modes. Moreover, by inputting the second voltage determined based on the first voltage for power control as the attenuation voltage to the attenuation module 130, the attenuation module 130 is reused during the power control process. Only one attenuation module 130 is provided in the circuit to implement attenuation adjustment in both the power control mode and the gain control mode, simplifying the circuit structure, reducing the number of components in the circuit, and further reducing the circuit footprint.

[0053] In one possible implementation, see Figure 2 As shown, the mode switching module 110 includes: two switches controlled by a mode selection signal;

[0054] A common terminal of the first switch S1 of the two switches is connected to the common terminal, a first terminal of the first switch S1 of the two switches is connected to a first terminal of the second switch S2 of the two switches, and a second terminal of the first switch S1 of the two switches is connected to a first terminal of the power control module 120;

[0055] A common terminal of the second switch S2 of the two switches is connected to a first terminal of the attenuation module 130 , and a second terminal of the second switch S2 of the two switches is connected to a second terminal of the power control module 120 .

[0056] In practical applications, the first switch S1 and the second switch S2 can be single-pole, double-throw (SPDT) analog voltage switches. Both the first switch S1 and the second switch S2 are controlled by a mode selection signal, and both switches operate simultaneously. When the mode selection signal indicates a gain control mode, the first switch S1 connects its common terminal to the first terminal, and the second switch S2 connects its common terminal to the first terminal. The first voltage input by the external controller is transmitted sequentially through the common terminal of the first switch S1, the first terminal of the first switch S1, the first terminal of the second switch S2, and the common terminal of the second switch S2 to the attenuation module 130. The attenuation module 130 uses the received first voltage as the attenuated voltage. When the mode selection signal indicates the power control mode, the first switch S1 is connected to its common terminal and the second terminal, and the second switch S2 is connected to its common terminal and the second terminal. The first voltage input by the external controller is transmitted to the power control module 120 via the common terminal of the first switch S1 and the second terminal of the first switch S1, so that the power control module 120 determines the second voltage that meets the power requirement based on the first voltage. The power control module 120 transmits the second voltage to the mode switching module 110 via the second terminal of the second switch S2. The mode switching module 110 transmits the second voltage to the attenuation module 130 via the common terminal of the second switch S2. The attenuation module 130 uses the received second voltage as the attenuation voltage.

[0057] In one possible implementation, see Figure 3 As shown, the power amplifier control circuit 100 further includes: a detection module 150;

[0058] The first end of the detection module 150 is connected to the third end of the power control module 120, the second end of the detection module 150 is connected to the second end of the power amplifier module 140, and the third end of the detection module 150 serves as the output end of the target RF signal; the detection module 150 is used to determine the detection voltage of the RF signal output by the power amplifier module 140.

[0059] In practical applications, the detection module 150 can detect the RF power currently output by the power amplifier module 140 and output a corresponding detection voltage. The detection voltage represents the amplitude of the currently output RF signal and corresponds to the current power. The detection voltage is then transmitted to the power control module 120, so that the power control module 120 determines a second voltage that meets the power requirement based on the first voltage and the detection voltage corresponding to the currently output RF power. The third terminal of the detection module 150 serves as the output terminal of the target RF signal, outputting the target RF signal obtained after power amplification by the power amplifier module 140.

[0060] In one possible implementation, see Figure 4 As shown, the power control module 120 includes: three resistors, a capacitor and two operational amplifiers;

[0061] A positive input terminal of the first operational amplifier OPA of the two operational amplifiers is connected to a first terminal of the detection module 150, a negative input terminal of the first operational amplifier OPA of the two operational amplifiers is connected to an output terminal of the first operational amplifier OPA of the two operational amplifiers via a first resistor R1 of the three resistors, and an output terminal of the first operational amplifier of the two operational amplifiers is connected to a first terminal of a second resistor R2 of the three resistors;

[0062] A positive input terminal of the second operational amplifier OPB of the two operational amplifiers is connected to the second terminal of the mode switching module 110 via the third resistor R3 of the three resistors, a negative input terminal of the second operational amplifier OPB of the two operational amplifiers is connected to the second terminal of the second resistor R2 of the three resistors, and an output terminal of the second operational amplifier OPB of the two operational amplifiers is connected to the fourth terminal of the mode switching module 110;

[0063] A first end of the capacitor C is connected to a second end of the second resistor R2 among the three resistors, and a second end of the capacitor C is connected to an output end of the second operational amplifier OPB among the two operational amplifiers.

[0064] In practical applications, the first operational amplifier (OPA) and the first resistor (R1) form a voltage follower. This voltage follower primarily ensures that its input voltage and output voltage are equal, preventing load changes from causing changes in the voltage follower's output voltage and minimizing the load effect. The second resistor (R2), the second operational amplifier (OPB), the third resistor (R3), and the capacitor (C) form an integrator, primarily used for integration. The detection voltage is input to the positive input of the first operational amplifier (OPA), passed through the first operational amplifier (OPA) and the second resistor (R2), and output to the negative input of the second operational amplifier (OPB). The first voltage is input to the negative input of the second operational amplifier (OPB). The integrator integrates the detection voltage and the first voltage to produce a second voltage. The expression for the second voltage is: V2 = b*f*(V1-Vi)+u(x), where V1 is the first voltage, V2 is the second voltage, Vi is the detection voltage, b is the amplification factor, f is the integration factor, x is the target output power corresponding to V1, and u(x) is the target power control voltage function. The target power reference value function can be determined by the following scheme: assuming the input power of the external RF signal generating device is x1, the target output power corresponding to the first voltage V1 is x, the gain value of the power amplifier module 140 is G1, and the adjusted attenuation value of the attenuation module 130 is ATT1, then ATT1 = G1 - (x - x1), where u(x) is the control voltage when the attenuation module 130 is adjusted to the attenuation value ATT1, where x1 and x are in dBm. Obviously, the determination of the second voltage V2 depends not only on the first voltage V1 input by the external controller and the detection voltage Vi input by the detection module 150, but also on the input power x1 of the external RF signal generating device and the target output power x corresponding to the first voltage V1.

[0065] In one possible implementation, see Figure 5 As shown, the power amplifier control circuit 100 further includes: a voltage regulation module 160;

[0066] A first end of the voltage regulating module 160 is connected to the external controller, and a second end of the voltage regulating module 160 is connected to a first end of the mode switching module 110 ; the voltage regulating module 160 is used to adjust the magnitude of the first voltage when the mode selection signal changes.

[0067] In practical applications, to prevent the power amplifier's control circuit from experiencing significant output power fluctuations when switching between two control modes, a voltage regulation module 160 is configured to adjust the magnitude of the first voltage based on slope matching when the mode selection signal changes. The regulation method of the voltage regulation module 160 is related to the attenuation pattern of the attenuation module 130. The attenuation pattern of the attenuation module 130 is primarily categorized as a positive correlation attenuation pattern and a negative correlation attenuation pattern. A positive correlation attenuation pattern means that the greater the attenuation voltage, the greater the attenuation of the attenuation module 130; a negative correlation attenuation pattern means that the greater the attenuation voltage, the smaller the attenuation of the attenuation module 130. Slope matching means that when the attenuation pattern of the attenuation module 130 is a positive correlation attenuation pattern, its slope is positive. In this case, the slope of the second voltage output by the power control module 120, i.e., the amplification factor and the integral factor, is set to a positive number. When the attenuation pattern of the attenuation module 130 is a negative correlation attenuation pattern, its slope is negative. In this case, the slope of the second voltage output by the power control module 120, i.e., the amplification factor and the integral factor, is set to a negative number. In order to minimize the gain or power of the RF signal when switching between the two control modes and effectively avoid severe jitter in the output power, if the attenuation law of the attenuation module 130 is a positive correlation attenuation law, when the two control modes are switched, the voltage regulation module 160 adjusts the first voltage input by the external controller to the maximum value; if the attenuation law of the attenuation module 130 is a negative correlation attenuation law, when the two control modes are switched, the voltage regulation module 160 adjusts the first voltage input by the external controller to the minimum value.

[0068] For specific implementation, see Figure 6As shown, if the attenuation law of the attenuation module is a positive correlation attenuation law, its attenuation is: A = a × Vs, where a is the attenuation coefficient, a is a positive number, A is the attenuation, and Vs is the attenuation voltage; the larger the attenuation voltage Vs, the greater the attenuation of the attenuation module. At this time, in order to avoid severe output power jitter when switching between the two control modes, based on the idea of slope matching, the relationship between the first input voltage and the second output voltage of the power control module is set to be positively correlated, that is, the second voltage output by the power control module is set to: V2 = b*f*(V1-Vi)+u(x), where the amplification coefficient b and the integration coefficient f are both positive numbers. When the slope of the attenuation, i.e., the attenuation coefficient a, is positive, the slope of the second voltage output by the power control module, i.e., the amplification coefficient b and the integral coefficient f, are set to positive numbers to achieve slope matching. As the first voltage V1 increases, in the power control mode, the second voltage V2 increases, further increasing the attenuation voltage Vs, increasing the attenuation A, and decreasing the power of the RF signal. In the gain control mode, an increase in the first voltage V1 causes an increase in the attenuation voltage Vs, increasing the attenuation A, and decreasing the gain of the RF signal. Therefore, when switching between modes, the first voltage V1 is set to its maximum value to minimize the gain or power of the RF signal when switching between the two control modes, thereby avoiding severe fluctuations in the output power when switching between the two control modes. If the attenuation law of the attenuation module is a negative correlation attenuation law, its attenuation is: A = a × Vs, where a is the attenuation coefficient, a is a negative number, A is the attenuation, and Vs is the attenuation voltage. The larger the attenuation voltage Vs, the smaller the attenuation of the attenuation module. At this time, to avoid the problem of severe output power fluctuations when switching between the two control modes, based on the concept of slope matching, the relationship between the first input voltage and the second output voltage of the power control module is set to a negative correlation, that is, the second voltage output by the power control module is set to: V2 = b*f*(V1-Vi)+u(x), where the amplification factor b and the integration factor f are both negative. When the slope of the attenuation, i.e., the attenuation factor a, is negative, the slope of the second voltage output by the power control module, i.e., the amplification factor b and the integration factor f, are set to negative numbers to achieve slope matching. As the first voltage V1 increases, in the power control mode, the second voltage V2 decreases, further resulting in a decrease in the attenuation voltage Vs, a decrease in the attenuation A, and an increase in the power of the RF signal; in the gain control mode, the first voltage V1 increases, resulting in a decrease in the attenuation voltage Vs, a decrease in the attenuation A, and an increase in the gain of the RF signal. Therefore, when switching between the two control modes, the first voltage V1 is set to the minimum value, so that the gain or power of the RF signal is minimized when switching between the two control modes, thereby avoiding severe output power fluctuations when switching between the two control modes.

[0069] In one possible implementation, see Figure 7 As shown, the attenuation module 130 includes: an attenuator.

[0070] In practical applications, the attenuator module is provided with an attenuator, which may be an analog attenuator. The attenuator mainly adjusts the gain of the radio frequency signal input from the external radio frequency signal generating device according to the attenuation voltage.

[0071] In one possible implementation, the attenuator is a positive slope analog attenuator or a negative slope analog attenuator.

[0072] In practical applications, if the attenuator is a positive-slope analog attenuator, its attenuation is: A = a × Vs, where a is the attenuation coefficient. If a is a positive number, the attenuation is A, and Vs is the attenuation voltage. As the attenuation voltage Vs increases, the attenuation of the positive-slope analog attenuator increases. If the attenuator is a negative-slope analog attenuator, its attenuation is: A = a × Vs, where a is the attenuation coefficient. If a is a negative number, the attenuation is A, and Vs is the attenuation voltage. As the attenuation voltage Vs increases, the attenuation of the positive-slope analog attenuator decreases.

[0073] In one possible implementation, see Figure 8 As shown, the detection module 150 includes: a radio frequency detector.

[0074] In practical applications, the RF detector is primarily used for RF signal detection, which may include peak detection, average detection, etc. The RF detector may be a zero-bias Schottky diode detector, a biased Schottky diode detector, a logarithmic detector, etc., without limitation herein. The RF detector may detect the detection voltage of the RF signal currently output by the power amplifier module 140 and transmit the detection voltage to the power control module 120, so that the power amplifier module 140 determines a second voltage that meets the power requirement based on the first voltage and the detection voltage of the currently output RF signal to achieve power control.

[0075] In one possible implementation, see Figure 9 The power amplifier module 140 shown includes a radio frequency power amplifier.

[0076] In practical applications, the RF power amplifier can be a high-gain amplifier, a medium-to-high power amplifier, or a low-noise amplifier, without limitation. The RF power amplifier can amplify the input RF signal based on a preset gain factor, ensuring that the power of the amplified RF signal reaches a value that meets the requirements of subsequent circuits.

[0077] In a possible implementation, a power amplifier with a gain of 50dB and a rated output power of 50dBm is used as an example to introduce the control circuit of the power amplifier. The mode switching module is set to a dual-channel analog switch, NC1 and NC2 are interconnected, and the default setting is the gain mode. The internal components of the dual-channel analog switch are as follows: Figure 10As shown; the first resistor R1, the second resistor R2 and the third resistor R3 included in the power control module are all 1kΩ, and the capacitor is 10nF; the attenuation module is set to a reverse slope analog attenuator. Under the conditions of an electromagnetic frequency of 2GHz, an internal operating voltage of 5V and a temperature of 25℃, the relationship between the control voltage and the attenuation is as follows Figure 11 As shown, the detection unit is set to a logarithmic linear RF detector, and the relationship between its output voltage and input power is as follows: Figure 12 By making the control circuit of the power amplifier work in different modes, the gain values or power values of the power amplifier corresponding to the first voltages input by different external controllers in different working modes of the control circuit of the power amplifier shown in Table 1 can be obtained.

[0078] Table 1

[0079]

[0080]

[0081] The data in Table 1 shows that the higher the first voltage input to the external controller, the greater the corresponding gain or power of the target RF signal. Due to the use of a reverse-slope analog attenuator, the first voltage input to the external controller can be set to less than 0.4V when switching between control modes, ensuring that the output power is less than 20dBm during the switching process. This effectively avoids the problem of severe output power jitter when switching between the two control modes, and does not affect the power amplifier, other modules, or external devices.

[0082] Based on the same inventive concept, an embodiment of the present invention further provides a radio frequency device, see Figure 13 As shown, the radio frequency device 200 may include any one of the above-mentioned power amplifier control circuits 100, the controller 210, the radio frequency signal receiving device 220, and the radio frequency signal transmitting device 230 provided in the embodiments of the present invention; the controller 210 is connected to the first end of the power amplifier control circuit 100, the radio frequency signal receiving device 220 is connected to the second end of the power amplifier control circuit 100, and the radio frequency signal receiving device 230 is connected to the third end of the power amplifier control circuit 100. Specifically, the controller 210 is connected to the first end of the mode switching module 110 of the power amplifier control circuit 100, the radio frequency signal receiving device 220 is connected to the second end of the attenuation module 130 of the power amplifier control circuit 100, and the radio frequency signal receiving device 230 is connected to the third end of the detection module 150 of the power amplifier control circuit 100. The functions thereof are detailed in the above-mentioned power amplifier control circuit embodiments and will not be repeated here.

[0083] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0084] Obviously, those skilled in the art may make various changes and modifications to the embodiments of the present application without departing from the spirit and scope of the embodiments of the present application. Thus, if these modifications and variations of the embodiments of the present application fall within the scope of the claims of the present application and their equivalents, the present application also intends to include such modifications and variations.

Claims

1. A power amplifier control circuit, characterized in that: include: Mode switching module, power control module, attenuation module, power amplifier module; The first end of the mode switching module is connected to the external controller, the second end of the mode switching module is connected to the first end of the power control module, and the third end of the mode switching module is connected to the first end of the attenuation module; the mode switching module is used to determine the current control mode according to the mode selection signal input by the external controller, and in the gain control mode, transmit the first voltage input by the external controller to the attenuation module as the attenuation voltage; in the power control mode, transmit the first voltage input by the external controller to the power control module, and transmit the second voltage returned by the power control module to the attenuation module as the attenuation voltage; The power control module is configured to determine, in a power control mode, a second voltage that meets the power requirement based on the first voltage, and transmit the second voltage to the mode switching module; The second end of the attenuation module is connected to the external RF signal generating device, and the third end of the attenuation module is connected to the first end of the power amplifier module; the attenuation module is used to adjust the attenuation of the RF signal input by the external RF signal generating device according to the attenuation voltage; The power amplifier module is used to amplify the power of the radio frequency signal output by the attenuation module to obtain a target radio frequency signal; The mode switching module includes: two switches controlled by a mode selection signal; The common terminal of the first switch of the two switches is connected to the external controller, the first terminal of the first switch of the two switches is connected to the first terminal of the second switch of the two switches, and the second terminal of the first switch of the two switches is connected to the first terminal of the power control module; A common terminal of the second switch of the two switches is connected to the first terminal of the attenuation module, and a second terminal of the second switch of the two switches is connected to the second terminal of the power control module; The power amplifier control circuit further includes: a detection module; The first end of the detection module is connected to the third end of the power control module, the second end of the detection module is connected to the second end of the power amplifier module, and the third end of the detection module serves as the output end of the target RF signal; the detection module is used to determine the detection voltage of the RF signal output by the power amplifier module.

2. The power amplifier control circuit according to claim 1, wherein: The power control module includes: three resistors, a capacitor and two operational amplifiers; The positive input terminal of the first operational amplifier of the two operational amplifiers is connected to the first terminal of the detection module, the negative input terminal of the first operational amplifier of the two operational amplifiers is connected to the output terminal of the first operational amplifier of the two operational amplifiers via the first resistor of the three resistors, and the output terminal of the first operational amplifier of the two operational amplifiers is connected to the first terminal of the second resistor of the three resistors; A positive input terminal of the second operational amplifier among the two operational amplifiers is connected to the second terminal of the mode switching module via a third resistor among the three resistors, a negative input terminal of the second operational amplifier among the two operational amplifiers is connected to the second terminal of the second resistor among the three resistors, and an output terminal of the second operational amplifier among the two operational amplifiers is connected to the fourth terminal of the mode switching module; The first end of the capacitor is connected to the second end of the second resistor among the three resistors, and the second end of the capacitor is connected to the output end of the second operational amplifier among the two operational amplifiers.

3. The power amplifier control circuit according to claim 2, wherein: Also includes: Voltage regulation module; The first end of the voltage regulating module is connected to the external controller, and the second end of the voltage regulating module is connected to the first end of the mode switching module; the voltage regulating module is used to adjust the magnitude of the first voltage when the mode selection signal changes.

4. The power amplifier control circuit according to claim 3, wherein: The attenuation module includes: an attenuator.

5. The power amplifier control circuit according to claim 4, wherein: The attenuator is a positive slope analog attenuator or a negative slope analog attenuator.

6. The power amplifier control circuit according to claim 4, wherein: The detection module includes: a radio frequency detector.

7. The power amplifier control circuit according to claim 6, wherein: The power amplifier module includes: a radio frequency power amplifier.

8. A radio frequency device, characterized in that: include: The power amplifier control circuit, controller, radio frequency signal receiving device, and radio frequency signal transmitting device according to any one of claims 1 to 7; the controller is connected to a first end of the power amplifier control circuit, the radio frequency signal receiving device is connected to a second end of the power amplifier control circuit, and the radio frequency signal receiving device is connected to a third end of the power amplifier control circuit.

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