Auxiliary control circuit of power amplifier module, power amplifier module and communication device

Abstract

The present invention relates to an auxiliary control circuit for a power amplifier module, a power amplifier module, and a communication device. The auxiliary control circuit of the power amplifier module includes a main control chip, a current detection chip, and a precision adjustment unit. The precision adjustment unit is connected in parallel with the precision control resistor of the current detection chip, and the switch control end of the precision adjustment unit is electrically connected to the main control chip, and is used to adjust the output voltage amplification factor of the current detection chip when receiving a switch signal output by the main control chip. The detection input end of the current detection chip is used to access the voltage to be measured of the power amplifier tube power supply path of the power amplifier module. The detection output end of the current detection chip is electrically connected to the main control chip. The main control chip is used to calculate the power amplifier current corresponding to the voltage to be measured after receiving the voltage signal output by the current detection chip. By arranging a precision adjustment unit on the power amplifier module and cooperating with the main control chip and the current detection chip, the effect of greatly improving the detection precision of the power amplifier current is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of current detection, and particularly to an auxiliary control circuit for a power amplifier module, a power amplifier module and a communication device. Background Art

[0002] With the continuous development of power electronics technology, in various communication devices of modern communication systems, current detection of power amplifier modules is an essential link. Through current detection, the magnitude of the working current of the power amplifier module in the communication device can be determined, and at the same time, the detected working current magnitude can be used as an alarm or a power amplifier feedback control quantity in the communication system. As an important part of the communication system, the main function of the power amplifier module is to amplify the communication signal in power to achieve the purpose of wider coverage and higher data transmission volume.

[0003] For the current detection of power amplifier modules, traditional current detection methods include detection resistor and integrated operational amplifier detection, current mutual inductance detection, Hall sensor detection, opto-coupler isolation current detection, and capacitor isolation current detection, etc. However, in the process of implementing the present invention, the inventors found that the traditional power amplifier current detection methods have the problem of low detection accuracy. Summary of the Invention

[0004] Based on this, in view of the above problems existing in the traditional power amplifier current detection methods, it is necessary to provide an auxiliary control circuit for a power amplifier module, a power amplifier module and a communication device.

[0005] To achieve the above object, the embodiments of the present invention provide the following technical solutions:

[0006] On the one hand, the embodiments of the present invention provide an auxiliary control circuit for a power amplifier module, including a main control chip, a current detection chip and a precision adjustment unit;

[0007] The precision adjustment unit is connected in parallel with the precision control resistor of the current detection chip, and the switch control end of the precision adjustment unit is electrically connected to the main control chip, and is used for adjusting the output voltage amplification factor of the current detection chip when receiving the switch signal output by the main control chip;

[0008] The detection input end of the current detection chip is used for accessing the voltage to be measured in the power supply path of the power amplifier tube of the power amplifier module, and the detection output end of the current detection chip is electrically connected to the main control chip. The main control chip is used for calculating the power amplifier current corresponding to the voltage to be measured after receiving the voltage signal output by the current detection chip.

[0009] In one of the embodiments, the precision adjustment unit includes a first program-controlled switch and a first auxiliary resistor, and the switch control end of the first program-controlled switch is electrically connected to the main control chip;

[0010] The input end of the first programmable switch is electrically connected to the first end of the precision control resistor, the output end of the first programmable switch is electrically connected to the first end of the first auxiliary resistor, and the second end of the first auxiliary resistor is electrically connected to the second end of the precision control resistor; the precision control resistor is the current detection resistor of the current detection chip or an external amplification resistor.

[0011] In one embodiment, the precision adjustment unit further includes a second programmable switch and a second auxiliary resistor, and the switch control end of the second programmable switch is electrically connected to the main control chip;

[0012] The input end of the second programmable switch is electrically connected to the first end of the precision control resistor, the output end of the second programmable switch is electrically connected to the first end of the second auxiliary resistor, and the second end of the second auxiliary resistor is electrically connected to the second end of the precision control resistor.

[0013] In one embodiment, the precision adjustment unit includes a series-connected first programmable switch and a first auxiliary resistor, and a series-connected second programmable switch and a second auxiliary resistor, and the precision control resistor is the current detection resistor of the current detection chip and an external amplification resistor;

[0014] The switch control end of the first programmable switch is electrically connected to the main control chip, the input end of the first programmable switch is electrically connected to the first end of the current detection resistor, and the second end of the first auxiliary resistor is electrically connected to the second end of the current detection resistor;

[0015] The switch control end of the second programmable switch is electrically connected to the main control chip, the input end of the second programmable switch is electrically connected to the first end of the external amplification resistor, and the second end of the second auxiliary resistor is electrically connected to the second end of the external amplification resistor.

[0016] In one embodiment, the auxiliary control circuit of the above power amplifier module further includes a gate voltage automatic adjustment circuit, and the input end of the gate voltage automatic adjustment circuit is electrically connected to the main control chip;

[0017] The gate voltage automatic adjustment circuit is used to adjust the gate voltage of the power amplifier tube of the power amplifier module after receiving the static current adjustment signal output by the main control chip.

[0018] In one embodiment, the auxiliary control circuit of the above power amplifier module further includes a power amplifier alarm circuit, the input end of the power amplifier alarm circuit is electrically connected to the main control chip, and the power amplifier alarm circuit is used to perform overcurrent alarm on the working current of the power amplifier module after receiving the alarm signal output by the main control chip.

[0019] On the other hand, a power amplifier module is further provided, including a radio frequency link and the auxiliary control circuit of the above power amplifier module.

[0020] On yet another aspect, a communication device is further provided, including the above power amplifier module.

[0021] In one embodiment, the above communication device further includes a current display device, and the current display device is electrically connected to the main control chip of the power amplifier module;

[0022] After receiving the working current signal output by the main control chip, the current display device is configured to display the working current of the power amplifier module; the working current is the current corresponding to the working voltage of the power supply path of the power amplifier tube of the power amplifier module.

[0023] In one embodiment, the above communication device is any one of a repeater device, a radio remote head device, a track power amplifier device, an integrated power amplifier, and a receiver.

[0024] One of the above technical solutions has the following advantages and beneficial effects:

[0025] For the auxiliary control circuit, the power amplifier module, and the communication device of the above power amplifier module, by setting a precision adjustment unit on the power amplifier module and cooperating with the main control chip and the current detection chip, the precision adjustment unit is turned on under the control of the switch signal of the main control chip and is connected to the current detection chip together with the precision control resistor to adjust the resistance value of the resistor connected to the current detection chip, so that the voltage amplification factor of the output of the current detection chip is variable. Since the static current is usually much lower than the working current and higher measurement precision is required, the voltage output precision of the current detection chip can be high when detecting the static current of the power supply path of the power amplifier tube, and the voltage output precision can be relatively lower than that in the static state when detecting the working current of the power supply path of the power amplifier tube, rather than using one current detection chip to complete the current detection of the entire process of the power supply path of the power amplifier tube, effectively solving the problem of low detection precision of the traditional power amplifier current detection method and achieving the effect of greatly improving the power amplifier current detection precision. Description of the Drawings

[0026] Figure 1 It is a radio frequency link block diagram of one conventional power amplifier module;

[0027] Figure 2 It is a schematic diagram of the voltage-current relationship curve of traditional power amplifier current detection;

[0028] Figure 3 It is a first structural schematic diagram of the auxiliary control circuit of the power amplifier module in one embodiment;

[0029] Figure 4 It is a circuit structural schematic diagram of the current detection chip in one embodiment;

[0030] Figure 5 It is a schematic diagram of the voltage-current relationship curve of the power amplifier current detection of the present application in one embodiment;

[0031] Figure 6Schematic diagram of the second structure of the auxiliary control circuit of the power amplifier module in an embodiment;

[0032] Figure 7 Schematic diagram of the third structure of the auxiliary control circuit of the power amplifier module in an embodiment;

[0033] Figure 8 Schematic diagram of the fourth structure of the auxiliary control circuit of the power amplifier module in an embodiment;

[0034] Figure 9 Schematic diagram of the fifth structure of the auxiliary control circuit of the power amplifier module in an embodiment;

[0035] Figure 10 Schematic diagram of the sixth structure of the auxiliary control circuit of the power amplifier module in an embodiment;

[0036] Figure 11 Schematic diagram of the structure of the power amplifier current detection circuit part of the communication device in an embodiment. Detailed implementation manners

[0037] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0038] It should be noted that unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific implementation manners and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0039] The power amplifier module mainly consists of two parts: a radio frequency link and an auxiliary control circuit. Among them, the radio frequency link part mainly consists of power amplifier devices such as a gain attenuation circuit, a pre-drive stage low-power amplifier transistor, a drive stage medium-power amplifier transistor, and a final stage high-power amplifier transistor, which are cascaded with isolators. According to the requirement of the gain size of the power amplifier module, the higher the gain requirement, the more two or more pre-drive stages can be cascaded. The auxiliary control circuit generally has any one or several of a power conversion circuit, a detection circuit, an IO external interface circuit, an alarm circuit, a control circuit, and a linearization circuit according to different functions. The radio frequency link block diagram of a common power amplifier module is as Figure 1 shown.

[0040] Generally, the main core device of the power amplifier module is the power amplifier transistor. There are various types of power amplifier transistors, and common ones are power amplifier transistors composed of materials such as LDMOS or GaN. The gain G and saturation power P of the power amplifier transistorsat There are also different grades. The gain of common power amplifier tubes is 17 dB - 22 dB. The saturation power P of the power amplifier tube sat has different grades such as 10 W, 20 W, 50 W, 100 W or 400 W, etc. Engineers can select different power amplifier tubes according to actual application needs to achieve the purpose of power amplification and realize the corresponding link functions.

[0041] In order to amplify the input signal Pin to the gain and power values required for the actual use of the entire communication system, usually, power amplifier tubes of different power grades are cascaded for use to amplify the signal and achieve the purpose of reasonably utilizing the gain and saturation power P of the power amplifier tube sat For power amplifier tubes, there are two relatively important indicators to pay attention to in actual use, namely the quiescent current and the operating current. The quiescent current is the current of the power amplifier tube when no input power enters. The magnitude of the quiescent current is controlled by the gate voltage of the power amplifier tube (i.e., the gate voltages VGS1 and VGS2 as shown Figure 1 in it). The quiescent current reflects the initial working state and the quiescent operating point of the power amplifier tube. The quiescent currents of power amplifier tubes with different saturation powers P sat are different. Generally speaking, the lower the saturation power P sat of the power amplifier tube, the lower the quiescent current. For example, the quiescent current of the 20 W saturation power P sat is about 100 mA - 200 mA, and the quiescent current of the 400 W saturation power P sat is about 1000 mA - 2000 mA.

[0042] The operating current is the dynamic current during the operation compared with the quiescent current. The magnitude of the operating current of the power amplifier tube is related to the signal power entering the power amplifier tube and reflects the efficiency and working state of the power amplifier tube. Through the operating current, it can be judged whether the power amplifier tube is in a normal working state, whether the efficiency is too high or too low. The operating currents of power amplifier tubes with different efficiencies and different output powers are different. Taking the power amplifier module powered by 28 V and outputting 80 W of RF power as an example, the approximate operating current range is 8 A - 10 A.

[0043] In traditional application scenarios, it is usually necessary to use a current detection chip to read the static current of the power amplifier tube in order to automatically adjust and set the gate voltage of the power amplifier tube in the power amplifier module; use a current detection chip to read the working current of the power amplifier tube in order to calculate the efficiency of the power amplifier module and determine whether the power amplifier module is abnormal. Commonly used current detection chips include INA138 and INA168 series chips from Texas Instruments (TI), MAX4173 and MAX4375 chips from MAXIM, and ADM4073 chips from Analog Devices (ADI). The integrated and optimized current detection IC chip has the characteristics of small size, high precision, and good performance, and is widely used in printed circuit boards.

[0044] In the application of integrated current detection chips, no matter what kind of current detection chip it is, it mainly consists of the following three parts: a detection resistor, the detection chip body, and an external detection voltage amplification circuit. The implementation principle is that a detection resistor on the chip detection input terminal is connected to the current path to be measured, and the flowing current will generate a voltage drop on the detection resistor. The detection chip body processes the voltage drop through an internal precision differential amplification circuit, and then the external detection voltage amplification circuit amplifies the detection voltage value corresponding to the voltage drop to an appropriate value and outputs it.

[0045] In actual applications, the inventor found that when traditional current detection chips are used in power amplifier modules, the difference between the static current and the working current of the power amplifier tube is relatively large. For example, the range of the static current is 100 mA to 1200 mA, while the range of the working current is 0 A to 10 A. The detection voltage finally output by the external detection voltage amplification circuit is converted from the detection voltage in the form of an analog signal into a corresponding digital signal by an AD (analog-to-digital conversion) chip and enters the main control chip such as an MCU or other programmable logic circuits, and then processed by the main control chip, or directly converted and processed using the internal AD (analog-to-digital conversion) port of the main control chip. Generally, the maximum detection voltage of the analog input of the AD port cannot exceed 3.3 V or 5 V. Then there will be a problem in actual use. Suppose the maximum analog voltage that the main control chip of the power amplifier module can detect is 5 V, the maximum working current of the power amplifier module is 10 A, the static current of the driver stage is 150 mA, and the static current of the final stage is 600 mA. When using a common current detection chip in cooperation with the main control chip for current detection, the detection voltage Vo output by the current detection chip and the detection current I calculated by the main control chip based on the detection voltage Vo are in a linear proportional relationship, as Figure 2 shown.

[0046] Vo = K * I; where K is the slope, which is the current detection accuracy. The larger K is, it means that when the detected current I changes by the same amount, the detected voltage Vo is larger, and it is easier to be detected by the MCU or AD, etc., that is, the detection accuracy is higher. For example, when the detected current changes by 10 mA, if the detected voltage only changes by 0.5 mV, it is difficult to accurately detect the change of 0.5 mV at this time. However, if the detected current changes by 10 mA and the detected voltage changes by 10 mV. Then, the detected voltage of 10 mV can be accurately detected.

[0047] Taking the example that when the current I in the current path to be detected is 10 A, the detected voltage output by the current detection chip is 5.0 V. When I = 5 A, the detected voltage Vo = 2.5 V, that is, 1 A corresponds to 500 mV, and 10 mA corresponds to a current detection accuracy of 5 mV, and this current detection accuracy is fixed. In the actual use of the power amplifier module, a higher current detection accuracy is required when detecting the static current. For example, it can reach an accuracy of 10 mA corresponding to 10 mV to accurately detect the static current, which is beneficial for accurately controlling the static current of the gate voltage of the power amplification tube on the power amplifier module; when detecting the working current, since the working current is relatively large, therefore, a detection accuracy of 1 A corresponding to 50 mV (10 mA corresponding to 0.5 mV) can also meet the actual use requirements, such as current alarm. That is to say, on the power amplifier module, the current detection chip requires a higher detection accuracy when detecting the static current, while a lower detection accuracy can be required when detecting the working current, which cannot be achieved in the traditional current detection method.

[0048] Please refer to Figure 3 In order to solve the problem of low detection accuracy in the power amplifier current detection method, in one embodiment, an auxiliary control circuit 100 of a power amplifier module is provided, including a main control chip 201, a current detection chip 12, and a precision adjustment unit 14. The precision adjustment unit 14 is connected in parallel with the precision control resistor of the current detection chip 12. The switch control end of the precision adjustment unit 14 is electrically connected to the main control chip 201, and is used to adjust the output voltage amplification factor of the current detection chip 12 when receiving the switch signal output by the main control chip 201. The detection input end of the current detection chip 12 is used to access the voltage to be measured of the power supply path 102 of the power amplifier tube of the power amplifier module. The detection output end of the current detection chip 12 is electrically connected to the main control chip 201. The main control chip 201 is used to calculate the power amplifier current corresponding to the voltage to be measured after receiving the voltage signal output by the current detection chip 12.

[0049] It can be understood that the current detection chip 12 is an existing current detection chip 12 in the art, such as any type of current detection chip 12 shown in the above example. The detection accuracy of the current detection chip 12 is related to the output voltage magnification factor, that is, the greater the magnification factor of the output voltage, the higher the accuracy of the current detection. The magnification factor of the output voltage is determined by the precision control resistor of the current detection chip 12, that is, the resistance value of the current detection resistor R14 and / or the resistor R31 in the external amplifier circuit, and the specific resistance value can be selected according to the detection accuracy required in the actual application. Therefore, by using the precision adjustment unit 14 to adjust the resistance value of the precision control resistor connected to the current detection chip 12, the detection accuracy of the current detection chip 12 when detecting the static current can be made higher than the detection accuracy of the current detection chip 12 when detecting the working current, thereby ensuring the higher accuracy required for static current detection and improving the gate voltage control accuracy of the power amplifier tube of the power amplifier module.

[0050] The power amplifier tube power supply path 102 of the power amplifier module also refers to the path for the power supply 101 of the power amplifier module to supply power to the driving stage power amplifier tube and the final stage power amplifier tube. The current sensing resistor in the detection input end of the current detection chip 12 is connected in a conventional manner in the art and is electrically connected to the power amplifier tube power supply path 102, so that the current in the power amplifier tube power supply path 102 can flow through the current sensing resistor in the detection input end of the current detection chip 12, so that the current detection chip 12 can detect the voltage on its current sensing resistor corresponding to the current flowing through, that is, the detection voltage. The precision adjustment unit 14 is a resistor element or a combination circuit with a switching function, which is used to connect the internal resistor in parallel to the precision control resistor after the internal switch is turned on, so as to adjust the resistance value of the precision control resistor actually connected to the current detection chip 12, so as to achieve the effect of controlling the output voltage amplification factor of the current detection chip 12.

[0051] The main control chip 201 is an MCU or other type of control chip already available on the power amplifier module in the art, and has RF link control function, current measurement function and other control functions required by the power amplifier module. The main control chip 201 can be a control chip that comes with the auxiliary control circuit, or it can be a master control unit provided on the power amplifier module, or it can be an external independently provided auxiliary control chip. The main control chip 201 is used to receive the static voltage output by the current detection chip 12, and then measure the corresponding static current to automatically control the gate voltage adjustment of the power amplifier tube; and to receive the working voltage output by the current detection chip 12, and then measure the corresponding working current to complete the working current monitoring and early warning of the power amplifier module. It should be noted that for ease of explanation, the present specification provides a drawing taking the INA138 series current detection chip 12 as an example, as shown in FIG. Figure 4The circuit structure diagram of the INA138 chip is shown as follows. For other types of current detection chips 12, it can be understood in the same way. It should be noted that Figure 3 is an example when the precision control resistor is used as the current detection resistor R14.

[0052] Specifically, when the power supply 101 of the power amplifier module starts to supply power and drive, the main control chip 201 outputs a switching signal to the precision adjustment unit 14 to control the precision adjustment unit 14 to cut off, so that the precision adjustment unit 14 is open at this time. The current detection resistor in the detection input end of the current detection chip 12 will generate a corresponding voltage drop, that is, the static voltage. The current detection chip 12 differentially amplifies the static voltage to meet the voltage input requirements of the main control chip 201 through its own internal precision differential amplifier circuit, and then outputs it to the main control chip 201. The main control chip 201 automatically reads the static voltage output by the current detection chip 12 with higher detection precision, and thus calculates the static current at the initial state when the power amplifier module starts to work from the static voltage, so as to judge whether the static current conforms to the set static current (or called the standard static current). If not, the main control chip 201 can directly or indirectly control the gate voltage of the power amplification tube of the power amplifier module to adjust the static current to the set value.

[0053] When it is determined that the static current conforms to the set static current, the main control chip 201 outputs another switching signal to the precision adjustment unit 14 to control the precision adjustment unit 14 to conduct, so that the precision adjustment unit 14 is connected in parallel to the current detection chip 12 at this time. The output voltage amplification factor of the current detection chip 12 will decrease due to the parallel connection of the precision adjustment unit 14. Therefore, the main control chip 201 automatically reads the working voltage output by the current detection chip 12, and the detection precision at this time is lower than that of the static current. The main control chip 201 can calculate the corresponding working current in real time based on the working voltage output by the current detection chip 12 during the normal startup and working period of the power amplifier module, so as to judge whether the working current is overcurrent. If so, the power amplifier current alarm function can be automatically completed. If not, the working current size of the power amplifier module can be continuously monitored or the working current size of the power amplifier module can be displayed in real time with the equipped display unit, etc.

[0054] It should be noted that the precision adjustment unit 14 can be connected to one side of the current detection resistor R14 of the current detection chip 12, or can be connected to one side of the resistor R31 in the external amplifier circuit. Two or more precision adjustment units 14 can also be set, so that at least one precision adjustment unit 14 is connected to both sides of the current detection resistor R14 and one side of the resistor R31 respectively. Specifically, it can be determined according to the adjustment requirements of the output voltage amplification factor of the current detection chip 12 in actual applications, as long as the auxiliary control circuit 100 of the power amplifier module can provide at least two different current detection precisions.

[0055] Through the above-mentioned precision adjustment unit 14, when the power amplifier tube power supply path 102 of the power amplifier module has a low current, the precision adjustment unit 14 is controlled to be cut off, so that the output voltage amplification factor of the current detection chip 12 is relatively large. When performing static current detection with the main control chip 201, the detection precision of the static current is higher, which is more conducive to static current control of the gate voltage of the power amplifier tube on the power amplifier module. When the power amplifier tube power supply path 102 of the power amplifier module has a high current, the precision adjustment unit 14 is controlled to be turned on, so that the output voltage amplification factor of the current detection chip 12 is relatively small. When performing working current detection with the main control chip 201, it is more suitable for the low detection precision situation where the working current is relatively large during alarm. In this way, the overall power amplifier current detection can have higher precision at low current (static current) and lower precision at high current (working current), which can meet the actual application requirements of low current and high current. Using the precision adjustment unit 14 to adjust the output voltage amplification factor of the current detection chip 12 to achieve the purpose of variable current detection precision can be applied in different application scenarios. The detection precision of the auxiliary control circuit 100 of the above-mentioned power amplifier module is as Figure 5 shown. 01 represents the detection precision curve of the current detection chip 12 when detecting static current, and 02 represents the detection precision curve of the current detection chip 12 when detecting working current.

[0056] For the auxiliary control circuit 100 of the above-mentioned power amplifier module, by setting the precision adjustment unit 14 on the power amplifier module and cooperating with the main control chip 201 and the current detection chip 12, the precision adjustment unit 14 is turned on under the control of the switch signal of the main control chip 201 and is connected to the current detection chip 12 together with the precision control resistor to adjust the resistance value of the resistor connected to the current detection chip 12, so that the output voltage amplification factor of the current detection chip 12 is variable. Since the static current is usually much lower than the working current and higher measurement precision is required, the switch control of the precision adjustment unit 14 can be used to achieve high voltage output precision of the current detection chip 12 when detecting the static current of the power amplifier tube power supply path 102, and the voltage output precision can be relatively lower than that in the static state when detecting the working current of the power amplifier tube power supply path 102, rather than using a single current detection chip 12 to complete the current detection of the entire process of the power amplifier tube power supply path. This effectively solves the problem of low detection precision in the traditional power amplifier current detection method and achieves the effect of greatly improving the power amplifier current detection precision.

[0057] Please refer to Figure 6, in one embodiment, the precision adjustment unit 14 includes a first programmable switch 142 and a first auxiliary resistor 144. The switch control terminal of the first programmable switch 142 is electrically connected to the main control chip 201. The input terminal of the first programmable switch 142 is electrically connected to the first end of the precision control resistor, and the output terminal of the first programmable switch 142 is electrically connected to the first end of the first auxiliary resistor 144. The second end of the first auxiliary resistor 144 is electrically connected to the second end of the precision control resistor. The precision control resistor is the current detection resistor of the current detection chip 12 or an external amplification resistor.

[0058] It can be understood that the first programmable switch 142 can be various existing programmable switches, and can be specifically selected according to the number of switch paths required by the application. The resistance value of the first auxiliary resistor 144 can be determined according to the adjustment requirement of the output voltage amplification factor of the current detection chip 12. For example, it can be determined based on the parallel resistance principle according to the output voltage amplification factor required for detecting the working current in the actual application scenario and the resistance value of the current detection resistor (or external amplification resistor). The external amplification resistor is the above-mentioned resistor R31. In this embodiment, the series-connected first programmable switch 142 and first auxiliary resistor 144 can be connected to the current detection resistor side of the current detection chip 12 or to the resistor R31 side of the current detection chip 12. By controlling the conduction or cut-off of the first programmable switch 142, the first auxiliary resistor 144 can be opened or connected in parallel, achieving the adjustment effect of the output voltage amplification factor of the current detection chip 12.

[0059] Through the combined application of the first programmable switch 142 and the first auxiliary resistor 144, it can effectively achieve the effect that the current detection chip 12 has a high voltage output precision when detecting the static current of the power amplifier tube power supply path 102, while the voltage output precision can be relatively lower than that in the static state when detecting the working current of the power amplifier tube power supply path 102, and the application cost is relatively low.

[0060] Please refer to Figure 7 , in one embodiment, the precision adjustment unit 14 further includes a second programmable switch 146 and a second auxiliary resistor 148. The switch control terminal of the second programmable switch 146 is electrically connected to the main control chip 201. The input terminal of the second programmable switch 146 is electrically connected to the first end of the precision control resistor. The output terminal of the second programmable switch 146 is electrically connected to the first end of the second auxiliary resistor 148. The second end of the second auxiliary resistor 148 is electrically connected to the second end of the precision control resistor.

[0061] It can be understood that the second programmable switch 146 can be a programmable switch of the same model as the first programmable switch 142, or a programmable switch of a different model from the first programmable switch 142, as long as it can control the connection and disconnection of the second auxiliary resistor 148 under the control of the main control chip 201. The second auxiliary resistor 148 can be the same as or different from the first auxiliary resistor 144, and the resistance value of the second auxiliary resistor 148 can be determined according to the adjustment requirement of the output voltage amplification factor of the current detection chip 12.

[0062] Specifically, in this embodiment, on one side of the current detection chip 12's current detection resistor or on one side of the resistor R31, a design of two precision adjustment units 14 is adopted. The main control chip 201 can respectively control the conduction and cut-off of the two programmable switches, and respectively achieve the highest detection precision adjustment when no auxiliary resistor is connected, the second-highest detection precision adjustment when one auxiliary resistor is connected, and the lowest detection precision adjustment when two auxiliary resistors are connected. Thus, the auxiliary control circuit 100 of the power amplifier module can support three different power amplifier current detection precisions, realizing a more refined detection of the current detection of the power amplifier module.

[0063] By applying two precision adjustment units 14, three different current detection precisions can be supported during the power amplifier current detection process, further improving the power amplifier current detection precision.

[0064] Please refer to Figure 8 , in one embodiment, the precision adjustment unit 14 includes a first programmable switch 142 and a first auxiliary resistor 144 connected in series, and a second programmable switch 146 and a second auxiliary resistor 148 connected in series. The precision control resistors are the current detection resistor R14 of the current detection chip 12 and the external amplification resistor R31. The switch control terminal of the first programmable switch 142 is electrically connected to the main control chip 201. The input terminal of the first programmable switch 142 is electrically connected to the first end of the current detection resistor. The second end of the first auxiliary resistor 144 is electrically connected to the second end of the current detection resistor. The switch control terminal of the second programmable switch 146 is electrically connected to the main control chip 201. The input terminal of the second programmable switch 146 is electrically connected to the first end of the external amplification resistor. The second end of the second auxiliary resistor 148 is electrically connected to the second end of the external amplification resistor.

[0065] It can be understood that in this embodiment, a precision adjustment unit 14 is provided on both the side of the current detection resistor of the current detection chip 12 and the side of the resistor R31. The main control chip 201 can respectively control the conduction and cut-off of the two programmable switches, achieving the effect of three different detection precisions to choose from.

[0066] Specifically, during the static current detection stage of the power amplifier module, the main control chip 201 can output switching signals to the two programmable switches respectively, controlling the two programmable switches to cut off so that the two auxiliary resistors are open. At this time, the output voltage amplification factor of the current detection chip 12 remains the maximum, so the high-precision detection requirement for small currents can be met. During the operating current detection stage of the power amplifier module, the main control chip 201 can output switching signals to the two programmable switches respectively, controlling either one or both of the two programmable switches to conduct, so that either one or both of the two auxiliary resistors are connected to the detection circuit. At this time, the output voltage amplification factor of the current detection chip 12 switches to a medium level or the minimum level, so the requirement for relatively reduced precision detection for large currents can be met.

[0067] By providing a precision adjustment unit 14 on both the current detection resistor side of the current detection chip 12 and the resistor R31 side, three different current detection precisions can also be supported during the power amplifier current detection process, further improving the power amplifier current detection precision.

[0068] In one embodiment, referring to the above design concept, those skilled in the art can also set more precision adjustment units 14 on the current detection resistor side and / or the resistor R31 side of the current detection chip 12 according to the refined detection and control requirements of current detection in actual applications, so as to meet the adjustment requirements of various current detection precisions and achieve a further improvement in current detection precision.

[0069] Please refer to Figure 9 , in one embodiment, the auxiliary control circuit of the above power amplifier module further includes a filter capacitor C1. One end of the filter capacitor C1 is electrically connected between the detection output end of the current detection chip 12 and the main control chip 201. The other end of the filter capacitor C1 is grounded.

[0070] It can be understood that in this embodiment, a filter capacitor C1 can also be connected between the detection output end of the current detection chip 12 and the main control chip 201 to filter out the clutter on the detection output end of the current detection chip 12, making the output DC voltage more stable. The parameter specifications of the filter capacitor C1 can be selected according to the power supply mode of the power amplifier module and the output characteristics of the current detection chip 12 in actual applications, as long as it can effectively provide the required clutter filtering function. By applying the above filter capacitor C1, a filtering effect is provided between the current detection chip 12 and the main control chip 201, making the output voltage of the current detection chip 12 more stable, eliminating the interference of clutter on the power amplifier current detection, and thus further improving the power amplifier current detection precision.

[0071] Please refer to Figure 10, in one embodiment, the auxiliary control circuit 100 of the above power amplifier module further includes a gate voltage automatic adjustment circuit 18. The input end of the gate voltage automatic adjustment circuit 18 is used for electrically connecting to the main control chip 201. The gate voltage automatic adjustment circuit 18 is configured to adjust the gate voltage of the power amplifier transistor of the power amplifier module after receiving the static current adjustment signal output by the main control chip 201.

[0072] It can be understood that the gate voltage automatic adjustment circuit 18 is a power amplifier transistor gate voltage adjustment circuit existing in the art. Specifically, during the operation of the power amplifier module, the static voltage detected by the current detection chip 12 is differentially amplified to an appropriate voltage level, then enters the main control chip 201, such as the MCU processing unit of the power amplifier module, after the noise is filtered by the filter capacitor C1. The MCU processing unit detects the corresponding static current based on the input static voltage, and compares this static current with the set static current to determine whether the current static current is correct. If not, the MCU processing unit automatically generates a corresponding static current adjustment signal and outputs this static current adjustment signal to the gate voltage automatic adjustment circuit 18. After receiving this static current adjustment signal, the gate voltage automatic adjustment circuit 18 adjusts the gate voltage of the corresponding power amplifier transistor according to this static current adjustment signal. In this way, after adjusting the gate voltage, the MCU processing unit detects the static current again based on the static voltage detected by the current detection chip 12 until the static current corresponding to the static voltage detected by the current detection chip 12 is the same as the set static current or within the floating range allowed by the set static current. If so, the MCU processing unit receives and detects the working current based on the working voltage output by the current detection chip 12.

[0073] Through the collaborative application of the current detection chip 12, the main control chip 201, and the gate voltage automatic adjustment circuit 18, it is possible to effectively achieve high-precision static current detection and at the same time achieve high-precision automatic adjustment of the gate voltage of the power amplifier transistor.

[0074] In one embodiment, as Figure 10 shown, the auxiliary control circuit 100 of the above power amplifier module further includes a power amplifier alarm circuit 20. The input end of the power amplifier alarm circuit 20 is electrically connected to the main control chip 201. The power amplifier alarm circuit 20 is configured to perform an over-current alarm on the working current of the power amplifier module after receiving the alarm signal output by the main control chip 201.

[0075] It can be understood that the power amplifier alarm circuit 20 is the power amplifier alarm circuit 20 provided in a traditional auxiliary control circuit in the art. Specifically, during the operation of the power amplifier module, the working voltage detected by the current detection chip 12 is differentially amplified to an appropriate voltage level, then enters the main control chip 201 after the clutter is filtered by the filter capacitor C2. The main control chip 201 detects the corresponding working current based on the input working voltage, and compares this working current with the set working current (or called the standard dynamic current) to determine whether the current working current is too large. If so, the main control chip 201 will automatically generate a corresponding alarm signal and output this alarm signal to the power amplifier alarm circuit 20. After receiving this alarm signal, the power amplifier alarm circuit 20 will perform an over-current alarm on the working current of the power amplifier module according to this alarm signal, for example, uploading the relevant information of the current alarm to the main control unit of the device where the power amplifier module is located or an external total control system. If not, the main control chip 201 will continue to receive and detect the working current based on the working voltage output by the current detection chip 12, or can output the data of the working current to the outside for external devices to perform linkage.

[0076] For easier understanding, on the power amplifier module, both the static current and the working current are the currents on the current path powered by the same power supply 101. Taking the design scheme shown as an example for illustration: Figure 6 As shown:

[0077] When it is necessary to switch to the high-precision current detection mode, the switch signal output by the MCU processing unit controls the first programmable switch 142 to cut off. At this time, the path resistance is the resistance value R1 of the current detection resistor R14. At this time, the voltage Vo output by the current detection chip 12 = K * R1 * I; K is the current detection accuracy (a constant).

[0078] When it is necessary to switch to the low-precision current detection mode, the switch signal output by the MCU processing unit controls the first programmable switch 142 to conduct. At this time, the parallel resistance value R of the current detection resistor R14 and the first auxiliary resistor 144 1b . R 1b < R1 and at the same time R 1b < R b , indicating R b the resistance value of the first auxiliary resistor 144. At this time, the voltage Vo output by the current detection chip 12 = K * R 1b * I. By selecting appropriate R1 and R according to the actual usage requirements bThe size can achieve the control of the current detection accuracy by controlling the conduction of the first programmed switch 142. For example, when setting the gate voltage of the power amplifier module, it is necessary to adjust the gate voltage to the magnitude corresponding to the required static current. Generally, the static current is relatively small (such as 100 mA to 900 mA), so a higher detection accuracy is required. Then, the MCU processing unit can be used to control the first programmed switch 142 to switch to the high-precision detection application mode. After the required static current is set, the detection of the working current will be carried out subsequently. The value of the working current is much larger than the static current (the working current range is, for example, 0 mA to 10 A). To ensure the current detection range of the auxiliary control circuit 100 of the power amplifier module, the detection accuracy can be sacrificed to obtain the required larger current detection range. At this time, the MCU processing unit can be used to control the first programmed switch 142 to switch to the low-precision detection application mode.

[0079] Taking the current detection chip 12 of the INA138 series as an example, assuming that the resistance value R1 of the current detection resistor R14 is 0.5 Ω, the current detection accuracy K = 8, and the resistance value R of the first auxiliary resistor 144 b is 0.05 Ω, with a static current of 800 mA and a working current of 8 A as examples: When detecting the static current, a high detection accuracy is required, so the first programmed switch 142 is controlled to be disconnected. At this time, according to the characteristics of the circuit detection chip INA138, it can be known that Vo = 0.5 * K * I = 4I. When detecting the working current, a large detection dynamic range is required. At this time, the first programmed switch 142 is controlled to be turned on. According to the characteristics of the circuit detection chip INA138, it can be known that Vo = 0.04545 * K * I = 0.3636 * I. The static current is 800 mA, and the output voltage at this time is Vo = 4 * 0.8 = 3.6 V; when the working current is 8 A, the output voltage at this time is Vo = 0.3636 * 8 = 2.9088 V. It can be seen that through the above design, the difference in current detection accuracy can be 10 times, meeting the usage requirements for different current detection accuracies in different application scenarios of power amplifier current detection.

[0080] In one embodiment, a power amplifier module is further provided, including a radio frequency link and the auxiliary control circuit 100 of the above power amplifier module.

[0081] It can be understood that for the explanation of the auxiliary control circuit 100 of the power amplifier module in this embodiment, specific reference can be made to the relevant explanations in the respective embodiments of the auxiliary control circuit 100 of the above power amplifier module for similar understanding, and no further elaboration will be repeated here.

[0082] The above-mentioned power amplifier module, through the combined application of the main control chip 201 and the auxiliary control circuit 100 of the above-mentioned power amplifier module, enables the current detection accuracy to be variable during the power amplifier current detection process, and can achieve high-precision measurement of the static current. At the same time, the measurement accuracy of the working current of the power supply path 102 of the power amplifier tube can also be well satisfied, rather than a single current detection chip 12 completing the current detection of the entire process of the power supply path of the power amplifier tube, effectively solving the problem of low detection accuracy of the traditional power amplifier current detection method and achieving the effect of greatly improving the power amplifier current detection accuracy.

[0083] In one embodiment, a communication device 200 is further provided, including the above-mentioned power amplifier module.

[0084] It can be understood by those skilled in the art that the above-mentioned communication device 200 can be various devices in a communication system that apply the power amplifier module to perform power amplifier current detection and alarm. The above-mentioned communication device may further include other components other than the power amplifier module, such as but not limited to a storage device, a transceiver antenna, and a data conversion circuit, etc.

[0085] The above-mentioned communication device 200, by applying the above-mentioned power amplifier module, can make the current detection accuracy variable during the power amplifier current detection process, and can achieve high-precision measurement of the static current. At the same time, the measurement accuracy of the working current of the power supply path 102 of the power amplifier tube can also be well satisfied, effectively solving the problem of low detection accuracy of the traditional power amplifier current detection method and achieving the effect of greatly improving the power amplifier current detection accuracy.

[0086] Please refer to Figure 11 , in one embodiment, the above-mentioned communication device 200 further includes a current display device 201. The current display device 201 is electrically connected to the main control chip 201 of the power amplifier module. After receiving the working current signal output by the main control chip 201, the current display device 201 is used to display the working current of the power amplifier module. The working current is the current corresponding to the working voltage of the power supply path 102 of the power amplifier tube of the power amplifier module.

[0087] It can be understood that the current display device 201 is a display device with data display or data display and broadcast functions, such as a touch display, a non-touch display, or a common display screen without a control input function. The current display device 201 can be independently set with discrete components on the communication device 200 from the power amplifier module, or can be integrally set in an integrated packaging manner. The specific setting method can be determined according to the size and shape of the current display device 201, and the auxiliary functions it has (such as touch input, button input, or floating operation input, etc.).

[0088] Specifically, during the operation of the power amplifier module, the working voltage output by the current detection chip 12 is differentially amplified to a suitable voltage, and then filtered out by the filter capacitor C1 before entering the MCU processing unit. The MCU processing unit obtains the corresponding working current based on the input working voltage detection, and compares the working current with the set working current (or standard dynamic current) to determine whether the current working current is too large. If so, the MCU processing unit will link the power amplifier alarm circuit 20 to the power amplifier module to issue an overcurrent alarm for the working current. If not, the MCU processing unit will continue to receive and detect the working current based on the working voltage output by the current detection chip 12, and output the real-time working current to the current display device 201. The current display device 201 can display the real-time working current data in the form of numerical values ​​or curves, or numerical values ​​and curves, so that the operation and maintenance personnel can know the working current size of the power amplifier module in the communication device 200 at any time, thereby determining the working state of the power amplifier module.

[0089] Through the combined application of the power amplifier module and the current display device 201, a real-time display function of the working current can be realized during the working current detection process of the power amplifier module.

[0090] In one embodiment, the communication device 200 is any one of a repeater device, a radio frequency remote device, a track power amplifier device, an integrated power amplifier and a receiver.

[0091] It can be understood that the communication device 200 using the above power amplifier module can be any one of the repeater equipment, radio frequency remote equipment, track power amplifier equipment, integrated power amplifier and receiver in the field, so as to improve the power amplifier current detection accuracy of the equipment, thereby more accurately controlling the gate voltage of the power amplifier tube, and completing the functions of power amplifier alarm or current display. It can be understood by those skilled in the art that the above list is only a few common communication devices 200, and the above power amplifier module can also be used in other devices that need to have a power amplifier current detection function.

[0092] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0093] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An auxiliary control circuit for a power amplifier module, characterized in that, It includes a main control chip, a current detection chip, and a precision adjustment unit; The precision adjustment unit is connected in parallel with the precision control resistor of the current detection chip. The switch control end of the precision adjustment unit is electrically connected to the main control chip, and is used to adjust the output voltage amplification factor of the current detection chip when receiving the switch signal output by the main control chip; The current detection resistor in the detection input end of the current detection chip is used to access the voltage to be measured in the power amplifier tube power supply path of the power amplifier module. The detection output end of the current detection chip is electrically connected to the main control chip. After receiving the voltage signal output by the current detection chip, the main control chip is used to calculate the power amplifier current corresponding to the voltage to be measured; The precision adjustment unit includes a first program-controlled switch and a first auxiliary resistor connected in series, and a second program-controlled switch and a second auxiliary resistor connected in series. The precision control resistor is the current detection resistor and the external amplification resistor of the current detection chip; The switch control end of the first program-controlled switch is electrically connected to the main control chip. The input end of the first program-controlled switch is electrically connected to the first end of the current detection resistor. The output end of the first program-controlled switch is electrically connected to the first end of the first auxiliary resistor. The second end of the first auxiliary resistor is electrically connected to the second end of the current detection resistor; The switch control end of the second program-controlled switch is electrically connected to the main control chip. The input end of the second program-controlled switch is electrically connected to the first end of the external amplification resistor. The output end of the second program-controlled switch is electrically connected to the first end of the second auxiliary resistor. The second end of the second auxiliary resistor is electrically connected to the second end of the external amplification resistor. The first end of the external amplification resistor is electrically connected to the output end of the current detection chip, and the second end of the external amplification resistor is grounded.

2. The auxiliary control circuit of the power amplifier module according to claim 1, characterized in that It further includes a grid voltage automatic adjustment circuit, and the input end of the grid voltage automatic adjustment circuit is electrically connected to the main control chip; The grid voltage automatic adjustment circuit is used to adjust the grid voltage of the power amplifier tube of the power amplifier module after receiving the static current adjustment signal output by the main control chip.

3. The auxiliary control circuit of the power amplifier module according to claim 2, characterized in that, It further includes a power amplifier alarm circuit, and the input end of the power amplifier alarm circuit is electrically connected to the main control chip. The power amplifier alarm circuit is used to perform over-current alarm on the working current of the power amplifier module after receiving the alarm signal output by the main control chip.

4. A power amplifier module, characterized in that, It includes a radio frequency link and an auxiliary control circuit of the power amplifier module according to any one of claims 1 to 3.

5. A communication device, characterized in that, It includes the power amplifier module according to claim 4.

6. The communication device according to claim 5, characterized in that, It further includes a current display device, and the current display device is electrically connected to the main control chip of the power amplifier module; After receiving the working current signal output by the main control chip, the current display device is used to display the working current of the power amplifier module. The working current is the current corresponding to the working voltage of the power amplifier tube power supply path of the power amplifier module.

7. The communication device according to claim 5 or 6, characterized in that, The communication device is any one of a repeater device, a radio frequency remote unit, a track power amplifier device, an integrated power amplifier, and a receiver.

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