Static working parameter automatic adjusting circuit of GaN power amplifier and road side unit

Abstract

The utility model relates to a static working parameter automatic adjusting circuit of a GaN power amplifier and a road side unit. The static working parameter automatic adjusting circuit comprises a control module, an adjustable voltage generation module, a static adjusting module, a current detection module and a power amplifier. The current detection module detects the real-time working current of the power amplifier and outputs a current feedback signal; the control module outputs a corresponding control signal according to the current feedback signal; the adjustable voltage generation module generates a variable voltage according to the control signal; the static adjusting module generates an adjusting signal according to the variable voltage so as to adjust static working parameters of the power amplifier. According to the utility model, the static working parameters of the GaN power amplifier can be accurately and automatically adjusted according to the real-time working current of the GaN power amplifier, the accuracy and reliability of adjustment can be ensured, error factors caused by circuit devices can be avoided, and the problem that the grid voltage of the GaN power amplifier needs to be independently adjusted can be solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the voltage regulation field of power amplifier, more specifically, relate to a kind of static working parameter automatic regulating circuit and roadside unit of GaN power amplifier. BACKGROUND

[0002] At present, GaN (gallium nitride) power amplifier static working parameter adjustment is by manually adjusting the grid voltage of GaN power amplifier, observing the requirement that current reaches static working point, then fixing grid voltage. The specific adjustment mode includes: setting adjustable resistance, the grid of power amplifier is changed by adjusting the resistance value of adjustable resistance, or using semi-automatic control mode, that is, the working current of GaN power amplifier is observed by artificial observation, and the output signal of MCU is changed according to the observed working current, so as to realize software control DAC output voltage and realize the grid voltage change of power amplifier. However, in fact, the grid voltage of each GaN power amplifier static working point is different, and the circuit device error factor, so that no matter which way needs to adjust the grid voltage of GaN power amplifier separately. SUMMARY

[0003] The utility model provides a kind of static working parameter automatic regulating circuit and roadside unit of GaN power amplifier to solve the technical problems of prior art.

[0004] The utility model solves the technical problems thereof, and the technical scheme adopted is: a kind of static working parameter automatic regulating circuit of GaN power amplifier is constructed, including: control module, adjustable voltage generation module, static regulation module, current detection module and power amplifier;The power amplifier is GaN power amplifier;

[0005] The input end of the adjustable voltage generation module is connected with the output end of the control module, the output end of the adjustable voltage generation module is connected with the input end of the static regulation module, the output end of the static regulation module is connected with the control end of the power amplifier, and the current detection module is connected with the power amplifier and the control module respectively;

[0006] The current detection module is used to detect the real-time working current of the power amplifier and output current feedback signal;

[0007] The control module is used to output corresponding control signal to the adjustable voltage generation module according to the current feedback signal;

[0008] The adjustable voltage generation module is used to generate variable voltage according to the control signal;

[0009] The static adjustment module is configured to generate an adjustment signal according to the variable voltage and send the adjustment signal to a control end of the power amplifier to adjust a static working parameter of the power amplifier.

[0010] In the static working parameter automatic adjustment circuit of the GaN power amplifier, the adjustable voltage generation module comprises an input filter circuit, an output filter circuit, a reference voltage generation circuit and an adjustable voltage generation circuit.

[0011] The input end of the input filter circuit is connected with a power supply voltage, the output end of the input filter circuit is grounded, the power supply end of the adjustable voltage generation circuit is connected with the power supply voltage, the input end of the output filter circuit is connected with the output end of the adjustable voltage generation circuit, the output end of the output filter circuit is grounded, and the output end of the adjustable voltage generation circuit is also connected with the input end of the static adjustment module.

[0012] The input end of the reference voltage generation circuit is connected with the power supply voltage, the output end of the reference voltage generation circuit is connected with a reference end of the adjustable voltage generation circuit, and the control end of the adjustable voltage generation circuit is connected with the output end of the control module as the input end of the adjustable voltage generation module.

[0013] In the static working parameter automatic adjustment circuit of the GaN power amplifier, the input filter circuit comprises a second capacitor, the output filter circuit comprises a first capacitor, the adjustable voltage generation circuit comprises a digital-analog conversion chip, and the reference voltage generation circuit comprises a second resistor, a fourth resistor and a third capacitor.

[0014] The input end of the second capacitor is connected with the power supply voltage, the output end of the second capacitor is grounded, the eighth pin of the digital-analog conversion chip is connected with the power supply voltage, the seventh pin of the digital-analog conversion chip is grounded, the first pin of the digital-analog conversion chip is connected with the input end of the static adjustment module, the first pin of the digital-analog conversion chip is also grounded through the first capacitor, the third pin of the digital-analog conversion chip is connected with the second end of the second resistor and the first end of the third capacitor, the second end of the third capacitor is grounded, the first end of the second resistor is connected with the power supply voltage, the first end of the fourth resistor is connected with the second end of the second resistor, the second end of the fourth resistor is grounded, the fourth pin, the fifth pin and the sixth pin of the digital-analog conversion chip are connected to the control module respectively.

[0015] The eighth pin of the digital-to-analog conversion chip is a power supply end of the adjustable voltage generation circuit, the first pin of the digital-to-analog conversion chip is an output end of the adjustable voltage generation circuit, the fourth pin, the fifth pin and the sixth pin of the digital-to-analog conversion chip are input ends of the adjustable voltage generation circuit, and the third pin of the digital-to-analog conversion chip is a reference end of the adjustable voltage generation circuit.

[0016] The static adjustment module comprises an operational amplifier circuit.

[0017] The first input end of the operational amplifier circuit is connected with the output end of the adjustable voltage generation module, the second input end of the operational amplifier circuit is connected with a power supply signal, and the output end of the operational amplifier circuit is connected with the control end of the power amplifier.

[0018] The operational amplifier circuit comprises an operational amplifier, a third resistor, a fifth resistor and a first resistor.

[0019] The positive input end of the operational amplifier is connected with the output end of the adjustable voltage generation module, the negative input end of the operational amplifier is connected with the power supply signal through the third resistor, the output end of the operational amplifier is connected with the control end of the power amplifier through the first resistor, and the fifth resistor is connected between the negative input end and the output end of the operational amplifier.

[0020] The current detection module comprises a current detection circuit, a current signal processing circuit and a pull-up circuit.

[0021] The current detection circuit is connected in series on a drain power supply loop of the power amplifier, the input end of the current signal processing circuit is connected with the current detection circuit, the output end of the current signal processing circuit is connected with the control module, and the pull-up circuit is connected with the output end of the current signal processing circuit.

[0022] The current detection circuit comprises a detection resistor, the current signal processing circuit comprises a current detection chip, and the pull-up circuit comprises a tenth resistor and an eleventh resistor.

[0023] The first end of the detection resistor is connected with the drain electrode power supply, and the second end of the detection resistor is connected with the tenth pin of the current detection chip;The ninth pin of the current detection chip is connected with the first end of the detection resistor, and the fourth pin and the fifth pin of the current detection chip are connected with the control module respectively;The first end of the tenth resistor is connected with the fifth pin of the current detection chip, the second end of the tenth resistor is connected with the chip voltage, and the first end of the eleventh resistor is connected with the fourth pin of the current detection chip, and the second end of the eleventh resistor is connected with the chip voltage.

[0024] The GaN power amplifier static working parameter automatic adjustment circuit further comprises a power amplifier filtering module and a storage module.

[0025] The power amplifier filtering module is connected with the control end and the power supply end of the power amplifier respectively, and is used for filtering the adjustment signal and the drain electrode power supply of the power amplifier respectively.

[0026] The storage module is connected with the control module and is used for storing the adjustable voltage setting value.

[0027] The GaN power amplifier static working parameter automatic adjustment circuit further comprises a power amplifier filtering module and a storage module.

[0028] The input end of the filter current limiting circuit is connected with the output end of the static adjustment module, and the output end of the filter current limiting circuit is connected with the control end of the power amplifier;The input end of the power supply filtering circuit is connected with the drain electrode power supply of the power amplifier, and the output end of the power supply filtering circuit is connected with the power supply end of the power amplifier.

[0029] The power supply filtering circuit comprises a fourth capacitor and a fifth capacitor;The filter current limiting circuit comprises a seventh capacitor, an eighth capacitor and a ninth resistor.

[0030] The first end of the fourth capacitor is connected with the drain electrode power supply, the second end of the fourth capacitor is grounded, and the fifth capacitor is connected with the fourth capacitor in parallel.

[0031] The first end of the seventh capacitor and the first end of the ninth resistor are connected with the output end of the static adjustment module, the second end of the seventh capacitor is grounded, the second end of the ninth resistor is connected with the control end of the power amplifier, and the eighth capacitor is connected with the seventh capacitor in parallel.

[0032] The utility model further provides a road side unit, which comprises the GaN power amplifier static working parameter automatic adjustment circuit.

[0033] The static working parameter automatic adjusting circuit of the GaN power amplifier has the following beneficial effects: including: a control module, an adjustable voltage generation module, a static adjusting module, a current detection module, and a power amplifier; the current detection module detects the real-time working current of the power amplifier and outputs a current feedback signal; the control module outputs a corresponding control signal according to the current feedback signal; the adjustable voltage generation module generates a variable voltage according to the control signal; and the static adjusting module generates an adjusting signal according to the variable voltage to adjust the static working parameter of the power amplifier. The GaN power amplifier can be precisely and automatically adjusted according to the real-time working current, the accuracy and reliability of the adjustment can be ensured, the error factors caused by circuit devices can be avoided, and the problem of separately adjusting the gate voltage of the GaN power amplifier can be solved. BRIEF DESCRIPTION OF DRAWINGS

[0034] The utility model will be further described below in combination with the drawings and examples, and the drawings are as follows:

[0035] Figure 1 It is the principle block diagram of the static working parameter automatic adjusting circuit of the GaN power amplifier provided by the utility model;

[0036] Figure 2 It is the circuit diagram of the adjustable voltage generation module provided by the utility model;

[0037] Figure 3 It is the circuit diagram of the static adjusting module provided by the utility model;

[0038] Figure 4 It is the circuit diagram of the current detection module provided by the utility model;

[0039] Figure 5 It is the circuit diagram of the power amplifier filter module and the power amplifier provided by the utility model;

[0040] Figure 6 It is the control logic diagram of the static working parameter automatic adjusting circuit of the GaN power amplifier provided by the utility model. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0042] In order to solve the problem of static working parameter adjustment of the existing GaN power amplifier, the utility model provides a kind of static working parameter automatic adjustment circuit of GaN power amplifier, it can be based on the real-time detection of the working current of GaN power amplifier, adjustable voltage is automatically adjusted by current feedback, realize the automatic adjustment of the static working parameter of GaN power amplifier.

[0043] Reference Figure 1 , Figure 1 The principle block diagram of a preferred embodiment of the static working parameter automatic adjustment circuit of GaN power amplifier provided by the utility model.

[0044] Specifically, as shown in Figure 1 The static working parameter automatic adjustment circuit of GaN power amplifier includes: control module 11, adjustable voltage generation module 12, static adjustment module 13, current detection module 14 and power amplifier. The power amplifier is GaN power amplifier. The input end of adjustable voltage generation module 12 is connected with the output end of control module 11, the output end of adjustable voltage generation module 12 is connected with the input end of static adjustment module 13, the output end of static adjustment module 13 is connected with the control end of power amplifier, and current detection module 14 is connected with power amplifier and control module 11 respectively.

[0045] Further, as shown in Figure 1 The static working parameter automatic adjustment circuit of GaN power amplifier further includes: power amplifier filter module 16 and storage module 15. The control end and power supply end of power amplifier are respectively connected with power amplifier filter module 16, for filtering processing to adjustment signal and drain power supply of power amplifier respectively. Storage module 15 is connected with control module 11, for storing adjustable voltage setting value. The storage module 15 can be independently set or built-in in control module 11. Optionally, the storage module 15 can be EEPROM memory.

[0046] In the utility model embodiment, current detection module 14 is used for detecting the real-time working current of power amplifier and outputting current feedback signal; control module 11 is used for outputting corresponding control signal to adjustable voltage generation module 12 according to current feedback signal; adjustable voltage generation module 12 is used for generating variable voltage according to control signal; static adjustment module 13 is used for generating adjustment signal according to variable voltage, and sending adjustment signal to the control end of power amplifier, to adjust the static working parameter of power amplifier.

[0047] Specifically, as shown in Figure 1As shown, the control module 11 controls the adjustable voltage Vo generated by the adjustable voltage generation module 12, and the generated adjustable voltage Vo is input to the static adjustment module 13 to generate a corresponding adjustment signal Vgs through the static adjustment module 13, and finally adjust the gate voltage of the power amplifier through the adjustment signal Vgs. Different gate voltages Vgs correspond to different working states of the GaN power amplifier, and different working currents on the drain power supply of the GaN power amplifier. By setting the current detection module 14 on the drain power supply circuit, the working current of the GaN power amplifier is detected in real time by the current detection module 14, and is fed back to the control module 11. The control module 11 adjusts the adjustable voltage Vo output by the adjustable voltage generation module 12 based on the current real-time working current, realizes automatic control of the gate voltage of the GaN power amplifier, and saves the current adjustable voltage setting value (i.e. adjustable voltage setting) of the adjustable voltage generation module 12 to the storage module 15 when the current working current is within the preset range. It should be noted that the static working parameter automatic adjustment circuit of the GaN power amplifier automatically reads the current adjustable voltage setting value in the storage module 15 at each power-on, and then controls the adjustable voltage generation module 12 to output the corresponding adjustable voltage according to the read adjustable voltage setting value, so as to ensure that the GaN power amplifier works in the required working state at each power-on, and also ensures the safety of the circuit device and the system.

[0048] In some embodiments, the adjustable voltage generation module 12 includes an input filter circuit, an output filter circuit, a reference voltage generation circuit, and an adjustable voltage generation circuit. The input end of the input filter circuit is connected to the supply voltage, the output end of the input filter circuit is grounded, and the supply end of the adjustable voltage generation circuit is connected to the supply voltage. The input end of the output filter circuit is connected to the output end of the adjustable voltage generation circuit, the output end of the output filter circuit is grounded, and the output end of the adjustable voltage generation circuit is also connected to the input end of the static adjustment module 13. The input end of the reference voltage generation circuit is connected to the supply voltage, the output end of the reference voltage generation circuit is connected to the reference end of the adjustable voltage generation circuit, and the control end of the adjustable voltage generation circuit is connected to the output end of the control module 11 as the input end of the adjustable voltage generation module 12.

[0049] Specifically, the input filter circuit is configured to filter the power supply voltage connected to the input terminal of the adjustable voltage generation circuit, so as to filter out interference signals and ensure the stability and reliability of the power supply voltage. The output filter circuit is configured to filter the adjustable voltage generated by the adjustable voltage generation circuit, so as to filter out interference signals and ensure the stability and reliability of the output adjustable voltage. The reference voltage generation circuit is configured to generate a corresponding reference voltage based on the power supply voltage, so that the adjustable voltage generation circuit can generate a corresponding adjustable voltage based on the reference voltage and the control signal of the control module 11. The reference voltage generation circuit can ensure that the adjustable voltage generated by the adjustable voltage generation circuit is within the range of 0-1.5V.

[0050] Specifically, in some embodiments, as shown in Figure 2 the input filter circuit includes a second capacitor C2, the output filter circuit includes a first capacitor C1, the adjustable voltage generation circuit includes a digital-to-analog conversion chip U1, and the reference voltage generation circuit includes a second resistor R2, a fourth resistor R4, and a third capacitor C3.

[0051] The input terminal of the second capacitor C2 is connected to the power supply voltage, the output terminal of the second capacitor C2 is grounded, the eighth pin of the digital-to-analog conversion chip U1 is connected to the power supply voltage, the seventh pin of the digital-to-analog conversion chip U1 is grounded, the first pin of the digital-to-analog conversion chip U1 is connected to the input terminal of the static adjustment module 13, the first pin of the digital-to-analog conversion chip U1 is also grounded through the first capacitor C1, the third pin of the digital-to-analog conversion chip U1 is connected to the second terminal of the second resistor R2 and the first terminal of the third capacitor C3, the second terminal of the third capacitor C3 is grounded, the first terminal of the second resistor R2 is connected to the power supply voltage, the first terminal of the fourth resistor R4 is connected to the second terminal of the second resistor R2, the second terminal of the fourth resistor R4 is grounded, and the fourth pin, the fifth pin, and the sixth pin of the digital-to-analog conversion chip U1 are connected to the control module 11 respectively; the eighth pin of the digital-to-analog conversion chip U1 is the power supply terminal of the adjustable voltage generation circuit, the first pin of the digital-to-analog conversion chip U1 is the output terminal of the adjustable voltage generation circuit, the fourth pin, the fifth pin, and the sixth pin of the digital-to-analog conversion chip U1 are the input terminals of the adjustable voltage generation circuit, and the third pin of the digital-to-analog conversion chip U1 is the reference terminal of the adjustable voltage generation circuit.

[0052] Specifically, as shown in Figure 2As shown, the digital-to-analog converter chip U1 (i.e., DAC) outputs 0V by default upon power-up, meaning the adjustable voltage is 0V. The REF input is the DAC's reference input voltage (i.e., reference voltage), configured as a 1.5V reference based on the supply voltage (VDAC_5V) using external voltage divider resistors (R2 and R4), thus ensuring the Vo output range is 0-1.5V. The second capacitor C2 forms the input filter circuit, filtering VDAC_5V to remove interference signals. The first capacitor C1 forms the output filter circuit, filtering Vo to remove interference signals and ensuring Vo's stability and reliability. Figure 2 In this configuration, the DAC's fourth pin (CS), fifth pin (SCLK), and sixth pin (DIN) are controlled by the control module 11. The control module 11 transmits SPI digital signals to the DAC, where CS is the selection signal, SCLK is the clock signal, and DIN is the data input signal. The adjustable voltage Vo is a voltage signal ranging from 0 to 1.5V.

[0053] In some embodiments, the static adjustment module 13 includes an operational amplifier circuit. A first input terminal of the operational amplifier circuit is connected to the output terminal of the adjustable voltage generation module 12, a second input terminal of the operational amplifier circuit is connected to a power supply signal, and the output terminal of the operational amplifier circuit is connected to the control terminal of a power amplifier.

[0054] like Figure 3 As shown, the operational amplifier circuit includes: operational amplifier U2, a third resistor R3, a fifth resistor R5, and a first resistor R1. The positive input terminal of operational amplifier U2 is connected to the output terminal of the adjustable voltage generation module 12. The negative input terminal of operational amplifier U2 is connected to the power supply signal (Vcc_5V) through the third resistor R3. The output terminal of operational amplifier U2 is connected to the control terminal of the power amplifier through the first resistor R1. The fifth resistor R5 is connected between the negative input terminal and the output terminal of operational amplifier U2. Specifically, as shown... Figure 3 As shown, the positive input terminal of operational amplifier U2 is connected to the first pin of the DAC to receive the Vo output of the DAC.

[0055] like Figure 3 As shown, the positive input terminal of operational amplifier U2 receives Vo, and the negative voltage output of the adjustment signal (i.e., Vgs) is controlled by adjusting the voltage of Vo. Where Vgs = 2Vo - 5. When the DAC output is 0V upon power-up, Vgs is -5V, and the GaN power amplifier is in the off state; when the DAC is adjusted to its maximum of 1.5V, Vgs is at its maximum of -2V, and the GaN power amplifier is in a safe operating state; the quiescent operating point Vgs of the selected GaN power amplifier is around -2.4V, specifically between -5V and -2V.

[0056] In some embodiments, the current detection module 14 comprises a current detection circuit, a current signal processing circuit, and a pull-up circuit. The current detection circuit is connected in series to the drain power supply loop of the power amplifier, the input of the current signal processing circuit is connected to the current detection circuit, the output of the current signal processing circuit is connected to the control module 11, and the pull-up circuit is connected to the output of the current signal processing circuit.

[0057] In some embodiments, as shown in Figure 4 , the current detection circuit comprises a detection resistor R8, the current signal processing circuit comprises a current detection chip U3, and the pull-up circuit comprises a tenth resistor R10 and an eleventh resistor R11. The first end of the detection resistor R8 is connected to the drain power supply, and the second end of the detection resistor R8 is connected to the tenth pin of the current detection chip U3. The ninth pin of the current detection chip U3 is connected to the first end of the detection resistor R8, and the fourth and fifth pins of the current detection chip U3 are connected to the control module 11 respectively. The first end of the tenth resistor R10 is connected to the fifth pin of the current detection chip U3, the second end of the tenth resistor R10 is connected to the chip voltage, the first end of the eleventh resistor R11 is connected to the fourth pin of the current detection chip U3, and the second end of the eleventh resistor R11 is connected to the chip voltage (Vcc_3.3V).

[0058] Specifically, as shown in Figure 4 , the detection resistor R8 is connected in series between Vds and the drain (D) of the GaN power amplifier, and the fourth capacitor C4 and the fifth capacitor C5 are connected after the second end of the detection resistor R8, i.e., the fourth capacitor C4 and the fifth capacitor C5 are close to the drain of the GaN power amplifier. At the same time, the two ends of the detection resistor R8 are connected to the ninth pin and the tenth pin of the current detection chip U3, realizing real-time detection of the working current of the GaN power amplifier. The detection resistor R8 is a precision resistor. Figure 4 As shown in , different currents produce different voltage differences across the detection resistor R8, so the current detection chip U3 samples the voltage difference across the detection resistor R8 and converts it into a current, and then feeds back the current to the control module 11, and the control module 11 outputs a corresponding control signal based on the feedback current.

[0059] As shown in Figure 4 , the sixth resistor R6 and the seventh resistor R7 form the upper resistors of the address line of the current detection chip U3, thereby ensuring stable input of the input signal. The fourth pin and the fifth pin of the current detection chip U3 are used to feed back a current feedback signal to the control module 11, wherein the current feedback signal is I 2C signal. The tenth resistor R10 and the eleventh resistor R11 are pull-up resistors of the SDA and DCL signals, and ensure the signal level. Optionally, the current detection chip U3 can adopt TPA626. Optionally, the control module 11 adopted in the embodiment of the utility model comprises an MCU, wherein the MCU is not shown in the figure, and the MCU can adopt a chip of the GD32F4 series to realize the function of the utility model.

[0060] In some embodiments, the power amplifier filtering module 16 comprises a power supply filtering circuit and a filtering current limiting circuit. The input end of the filtering current limiting circuit is connected to the output end of the static adjustment module 13, and the output end of the filtering current limiting circuit is connected to the control end of the power amplifier. The input end of the power supply filtering circuit is connected to the drain power supply of the power amplifier, and the output end of the power supply filtering circuit is connected to the power supply end of the power amplifier.

[0061] In some embodiments, as shown in the figure, Figure 5 The power supply filtering circuit comprises a fourth capacitor C4 and a fifth capacitor C5, and the filtering current limiting circuit comprises a seventh capacitor C7, an eighth capacitor C8 and a ninth resistor R9. The first end of the fourth capacitor C4 is connected to the drain power supply, the second end of the fourth capacitor C4 is grounded, and the fifth capacitor C5 is connected in parallel with the fourth capacitor C4. The first end of the seventh capacitor C7 and the first end of the ninth resistor R9 are connected to the output end of the static adjustment module 13, the second end of the seventh capacitor C7 is grounded, the second end of the ninth resistor R9 is connected to the control end of the power amplifier, and the eighth capacitor C8 is connected in parallel with the seventh capacitor C7. Figure 5 In some embodiments, U is a GaN power amplifier.

[0062] Specifically, as shown in the figure, Figure 5 The seventh capacitor C7 and the eighth capacitor C8 can be used for voltage stabilizing filtering of the gate power supply of the GaN power amplifier, the ninth resistor R9 is a current limiting resistor, and the tenth capacitor is an input matching capacitor. Wherein, RFTX is a radio frequency input signal, which is a radio frequency signal output by a front-stage amplifier in an RF link system. The fourth capacitor C4 and the fifth capacitor C5 are filtering capacitors of the drain voltage, and the sixth capacitor C6 is an output matching capacitor.

[0063] Reference Figure 6 , Figure 6 is a control logic diagram of the static working parameter automatic adjustment circuit provided in the embodiment of the utility model.

[0064] Specifically, as shown in the figure, Figure 6As shown, at the instant of system power-up, at this time, the DAC hardware output is 0V (which can ensure the safety of the device), Vgs is -5V, and the GaN power amplifier is in a judgment state. After power-up, the system enters an initialization process, at this time, the MCU reads the adjustable voltage setting value stored in the storage module 15, and sends the adjustable voltage setting value to the DAC through SPI, and the DAC outputs 1.3V according to the adjustable voltage setting value, at this time, the Vgs of the GaN power amplifier is about -2.4V, and the current on the Vds is about 35mA; the GaN power amplifier enters a working state. The MCU detects the GaN power amplifier in real time through the current feedback signal fed back by the current detection chip U3, if the feedback current is detected to be between 30-40mA, the static working current requirement is met, and the system saves the default setting value (i.e. the initially read adjustable voltage setting value) and works.

[0065] In actual work, due to the actual GaN power amplifier static working point deviation, operational amplifier and device error, the static current is not in the range of 30-40mA, if the system detects that the current is greater than 40mA, the voltage on the Vgs needs to be reduced to control the DAC output to be reduced, if the system detects that the current is less than 30mA, the voltage on the Vgs needs to be increased to control the DAC output to be increased. Through current feedback and adjustment of the DAC output, until the detection current is between 30-40mA, the system saves the current setting value in the EEPROM. It is guaranteed that the static working parameter DAC setting value saved in the EEPROM will not be changed each time the power is turned on or off or the program is upgraded.

[0066] Next time the power is turned on, the system reads the adjustable voltage setting value saved in the EEPROM and initializes the DAC. In the working process of the GaN power amplifier, if abnormality such as external environmental interference occurs, the system detects a large current, directly controls the DAC output to be 0V, and turns off the power amplifier, so that the GaN power amplifier can be protected to a certain extent.

[0067] Through the utility model, the DAC precise voltage control, real-time working current detection, automatic adjustment of the DAC output through current feedback, and automatic adjustment of the static working point of the GaN power amplifier can be realized. In addition, the setting efficiency of the static working point of the GaN power amplifier and power-on protection can be improved.

[0068] The utility model also provides a road side unit, the road side unit includes the utility model discloses the static working parameter automatic regulation circuit of GaN power amplifier.

[0069] In addition, the static working parameter automatic regulation circuit of GaN power amplifier disclosed by the utility model can be applied to a communication system, such as a transceiver system.

[0070] The above examples are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it accordingly, and cannot limit the protection scope of the present application. Any equivalent changes and modifications made within the scope of the claims of the present application shall belong to the scope of the claims of the present application.

Claims

1. A static operating parameter automatic adjusting circuit for GaN power amplifier, characterized in that, The application relates to a GaN power amplifier, which comprises a control module, an adjustable voltage generation module, a static adjustment module, a current detection module and a power amplifier; the power amplifier is a GaN power amplifier; the input end of the adjustable voltage generation module is connected with the output end of the control module; the output end of the adjustable voltage generation module is connected with the input end of the static adjustment module; the output end of the static adjustment module is connected with the control end of the power amplifier; the current detection module is connected with the power amplifier and the control module respectively; the current detection module is used for detecting the real-time working current of the power amplifier and outputting a current feedback signal; the control module is used for outputting a corresponding control signal to the adjustable voltage generation module according to the current feedback signal; the adjustable voltage generation module is used for generating a variable voltage according to the control signal; the static adjustment module is used for generating an adjustment signal according to the variable voltage and sending the adjustment signal to the control end of the power amplifier so as to adjust the static working parameter of the power amplifier. The adjustable voltage generation module comprises an input filter circuit, an output filter circuit, a reference voltage generation circuit and an adjustable voltage generation circuit; the input end of the input filter circuit is connected with a power supply voltage; the output end of the input filter circuit is grounded; the power supply end of the adjustable voltage generation circuit is connected with the power supply voltage; the input end of the output filter circuit is connected with the output end of the adjustable voltage generation circuit; the output end of the output filter circuit is grounded; the output end of the adjustable voltage generation circuit is also connected with the input end of the static adjustment module; the input end of the reference voltage generation circuit is connected with the power supply voltage; the output end of the reference voltage generation circuit is connected with the reference end of the adjustable voltage generation circuit; the control end of the adjustable voltage generation circuit is connected with the output end of the control module as the input end of the adjustable voltage generation module. The input filter circuit comprises a second capacitor; the output filter circuit comprises a first capacitor; the adjustable voltage generation circuit comprises a digital-analog conversion chip; the reference voltage generation circuit comprises a second resistor, a fourth resistor and a third capacitor; the input end of the second capacitor is connected with the power supply voltage; the output end of the second capacitor is grounded; the eighth pin of the digital-analog conversion chip is connected with the power supply voltage; the seventh pin of the digital-analog conversion chip is grounded; the first pin of the digital-analog conversion chip is connected with the input end of the static adjustment module; the first pin of the digital-analog conversion chip is also grounded through the first capacitor; the third pin of the digital-analog conversion chip is connected with the second end of the second resistor and the first end of the third capacitor; the second end of the third capacitor is grounded; the first end of the second resistor is connected with the power supply voltage; the first end of the fourth resistor is connected with the second end of the second resistor; the second end of the fourth resistor is grounded; the fourth pin, the fifth pin and the sixth pin of the digital-analog conversion chip are connected with the control module respectively. ​ ​ ​ ​ 2. The static operating parameter automatic adjusting circuit of GaN power amplifier according to claim 1, characterized in that, ​ ​ ​ 3. The static operating parameter automatic adjusting circuit of GaN power amplifier according to claim 2, characterized in that, ​ ​ The eighth pin of the digital-to-analog conversion chip is a power supply end of the adjustable voltage generation circuit, the first pin of the digital-to-analog conversion chip is an output end of the adjustable voltage generation circuit, the fourth pin, the fifth pin and the sixth pin of the digital-to-analog conversion chip are input ends of the adjustable voltage generation circuit, and the third pin of the digital-to-analog conversion chip is a reference end of the adjustable voltage generation circuit.

4. The static operating parameter automatic adjusting circuit of GaN power amplifier according to claim 1, characterized in that, The static adjustment module comprises an operational amplifier circuit. The first input end of the operational amplifier circuit is connected to the output end of the adjustable voltage generation module, the second input end of the operational amplifier circuit is connected to a power supply signal, and the output end of the operational amplifier circuit is connected to the control end of the power amplifier.

5. The static operating parameter automatic adjusting circuit of GaN power amplifier according to claim 4, characterized in that, The operational amplifier circuit comprises an operational amplifier, a third resistor, a fifth resistor and a first resistor. The positive input end of the operational amplifier is connected to the output end of the adjustable voltage generation module, the negative input end of the operational amplifier is connected to the power supply signal through the third resistor, the output end of the operational amplifier is connected to the control end of the power amplifier through the first resistor, and the fifth resistor is connected between the negative input end and the output end of the operational amplifier.

6. The static operating parameter automatic adjustment circuit of GaN power amplifier according to claim 1, characterized in that, The current detection module comprises a current detection circuit, a current signal processing circuit and a pull-up circuit. The current detection circuit is connected in series to the drain electrode power supply circuit of the power amplifier, the input end of the current signal processing circuit is connected to the current detection circuit, the output end of the current signal processing circuit is connected to the control module, and the pull-up circuit is connected to the output end of the current signal processing circuit.

7. The static operating parameter automatic adjustment circuit of GaN power amplifier according to claim 6, characterized in that, The current detection circuit comprises a detection resistor, the current signal processing circuit comprises a current detection chip, and the pull-up circuit comprises a tenth resistor and an eleventh resistor. The first end of the detection resistor is connected to the drain electrode power supply, the second end of the detection resistor is connected to the tenth pin of the current detection chip, the ninth pin of the current detection chip is connected to the first end of the detection resistor, the fourth pin and the fifth pin of the current detection chip are respectively connected to the control module, the first end of the tenth resistor is connected to the fifth pin of the current detection chip, the second end of the tenth resistor is connected to a chip voltage, the first end of the eleventh resistor is connected to the fourth pin of the current detection chip, and the second end of the eleventh resistor is connected to the chip voltage.

8. The static operating parameter automatic adjusting circuit of GaN power amplifier according to any one of claims 1-7, characterized in that, Further comprising: a power amplifier filtering module and a storage module; the power amplifier filtering module is connected to the control end and the power supply end of the power amplifier respectively, and is used for filtering the adjustment signal and the drain electrode power supply of the power amplifier respectively; the storage module is connected to the control module and is used for storing an adjustable voltage setting value.

9. The static operating parameter automatic adjustment circuit of GaN power amplifier according to claim 8, characterized in that, the power amplifier filtering module comprises a power supply filtering circuit and a filtering current limiting circuit. An input end of the filter current limiting circuit is connected with an output end of the static adjustment module, and an output end of the filter current limiting circuit is connected with a control end of the power amplifier; an input end of the power supply filter circuit is connected with a drain power supply of the power amplifier, and an output end of the power supply filter circuit is connected with a power supply end of the power amplifier; The power supply filter circuit comprises a fourth capacitor and a fifth capacitor, and the filter current limiting circuit comprises a seventh capacitor, an eighth capacitor and a ninth resistor; A first end of the fourth capacitor is connected with the drain power supply, a second end of the fourth capacitor is grounded, and the fifth capacitor is connected with the fourth capacitor in parallel; A first end of the seventh capacitor and a first end of the ninth resistor are connected with the output end of the static adjustment module, a second end of the seventh capacitor is grounded, a second end of the ninth resistor is connected with the control end of the power amplifier, and the eighth capacitor is connected with the seventh capacitor in parallel.

10. A roadside unit, comprising: The static working parameter automatic adjustment circuit of the GaN power amplifier.

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