CN111123772A - Auxiliary control circuit of power amplifier module, power amplifier module and communication equipment - Google Patents

Auxiliary control circuit of power amplifier module, power amplifier module and communication equipment Download PDF

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Publication number
CN111123772A
CN111123772A CN201911289335.9A CN201911289335A CN111123772A CN 111123772 A CN111123772 A CN 111123772A CN 201911289335 A CN201911289335 A CN 201911289335A CN 111123772 A CN111123772 A CN 111123772A
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power amplifier
current
chip
current detection
voltage
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朱金雄
樊奇彦
谢路平
曾晓松
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Comba Network Systems Co Ltd
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Comba Telecom Systems China Ltd
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    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B19/00—Programme-control systems
    • G05B19/02—Programme-control systems electric
    • G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
    • G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
    • G05B19/0423—Input/output
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
    • G05B2219/00—Program-control systems
    • G05B2219/20—Pc systems
    • G05B2219/24—Pc safety
    • G05B2219/24215—Scada supervisory control and data acquisition

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  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Amplifiers (AREA)

Abstract

The invention relates to an auxiliary control circuit of a power amplifier module, the power amplifier module and communication equipment. The auxiliary control circuit of the power amplifier module comprises a main control chip, a first current detection chip and a second current detection chip. The amplification factor of the output voltage of the first current detection chip is larger than that of the output voltage of the second current detection chip. The detection input end of the first current detection chip is used for accessing the static voltage of the power supply channel of the power amplifier tube of the power amplifier module. The detection output end of the first current detection chip is electrically connected with the main control chip. The first current detection chip is used for carrying out differential amplification on the static voltage and then outputting the static voltage to the main control chip. And the detection input end of the second current detection chip is used for accessing the working voltage of the power supply channel of the power amplifier tube. The detection output end of the second current detection chip is electrically connected with the main control chip. The second current detection chip is used for carrying out differential amplification on the working voltage and then outputting the working voltage to the main control chip. The effect of greatly improving the detection precision of the power amplifier current is achieved.

Description

Auxiliary control circuit of power amplifier module, power amplifier module and communication equipment
Technical Field
The invention relates to the technical field of current detection, in particular to an auxiliary control circuit of a power amplifier module, the power amplifier module and communication equipment.
Background
With the continuous development of power electronic technology, in various communication devices of modern communication systems, current detection of a power amplifier module is an essential link, the working current of the power amplifier module in the communication device can be determined through the current detection, and meanwhile, the detected working current can be used as an alarm or power amplifier feedback control quantity of the communication system. The power amplification module is used as an important component in a communication system and mainly plays a role in carrying out power amplification on communication signals so as to achieve the purposes of wider coverage and higher data transmission quantity.
For the current detection of the power amplifier module, the traditional current detection modes include detection resistance and integrated operational amplifier detection, current mutual inductance detection, hall sensing detection, optical coupling isolation current detection, capacitance isolation current detection and the like. However, in the process of implementing the invention, the inventor finds that the traditional power amplifier current detection mode has the problem of low detection precision.
Disclosure of Invention
Therefore, it is necessary to provide an auxiliary control circuit of a power amplifier module, a power amplifier module and a communication device for solving the above problems of the conventional power amplifier current detection method.
In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:
on one hand, the embodiment of the invention provides an auxiliary control circuit of a power amplifier module, which comprises a main control chip, a first current detection chip and a second current detection chip, wherein the amplification factor of the output voltage of the first current detection chip is greater than that of the second current detection chip;
the detection input end of the first current detection chip is used for accessing the static voltage of the power supply channel of the power amplifier tube of the power amplifier module, the detection output end of the first current detection chip is electrically connected with the main control chip, and the first current detection chip is used for differentially amplifying the static voltage and then outputting the amplified voltage to the main control chip;
the detection input end of the second current detection chip is used for accessing the working voltage of the power supply circuit of the power amplifier tube, the detection output end of the second current detection chip is electrically connected with the main control chip, and the second current detection chip is used for carrying out differential amplification on the working voltage and then outputting the working voltage to the main control chip.
In one embodiment, the detection input terminal of the first current detection chip and the detection input terminal of the second current detection chip are connected in series to the power supply path of the power amplifier tube through the same current detection resistor.
In one embodiment, the auxiliary control circuit of the power amplifier module further includes a first voltage stabilizing circuit, and the detection output terminal of the first current detection chip is electrically connected to the main control chip through the first voltage stabilizing circuit.
In one embodiment, the auxiliary control circuit of the power amplifier module further includes a second voltage stabilizing circuit, and the detection output terminal of the second current detection chip is electrically connected to the main control chip through the second voltage stabilizing circuit.
In one embodiment, the first voltage stabilizing circuit is a zener diode D1, and the second voltage stabilizing circuit is a zener diode D2;
the anode of the voltage-stabilizing diode D1 is grounded, and the cathode of the voltage-stabilizing diode D1 is electrically connected between the detection output end of the first current detection chip and the main control chip;
the anode of the zener diode D2 is grounded, and the cathode of the zener diode D2 is electrically connected between the detection output end of the second current detection chip and the main control chip.
In one embodiment, the auxiliary control circuit of the power amplifier module further includes a filter capacitor C1 and a filter capacitor C2;
one end of the filter capacitor C1 is electrically connected between the detection output end of the first current detection chip and the main control chip, and the other end of the filter capacitor C1 is grounded;
one end of the filter capacitor C2 is electrically connected between the detection output end of the second current detection chip and the main control chip, and the other end of the filter capacitor C2 is grounded.
In one embodiment, the auxiliary control circuit of the power amplifier module further includes an automatic gate voltage adjusting circuit, and an input end of the automatic gate voltage adjusting circuit is electrically connected to the main control chip;
the grid voltage automatic adjusting circuit is used for adjusting the grid voltage of the power amplification tube of the power amplification module after receiving the static current adjusting signal output by the main control chip.
In one embodiment, the auxiliary control circuit of the power amplifier module further includes a power amplifier alarm circuit, an input end of the power amplifier alarm circuit is electrically connected to the main control chip, and the power amplifier alarm circuit is configured to perform an overcurrent alarm on the operating current of the power amplifier module after receiving an alarm signal output by the main control chip.
On the other hand, the power amplifier module comprises the auxiliary control circuit of the power amplifier module.
In another aspect, a communication device is also provided, which includes the power amplifier module.
In one embodiment, the communication device further includes a current display device electrically connected to the main control chip of the power amplifier module;
the display device is used for displaying the working current of the power amplification module after receiving the working current signal output by the main control chip; the working current is the current corresponding to the working voltage of the power supply circuit of the power amplifier tube of the power amplifier module.
One of the above technical solutions has the following advantages and beneficial effects:
the auxiliary control circuit of the power amplifier module, the power amplifier module and the communication device apply two current detection chips with different voltage amplification factors on the power amplifier module, wherein the first current detection chip is used for detecting the static voltage of a power supply access of the power amplifier tube, so that the main control chip can calculate the static current of the power amplifier module by the static voltage. The second current detection chip is used for detecting the working voltage of the power supply channel of the power amplifier tube, so that the main control chip can calculate the working current of the power amplifier module according to the working voltage. Because of quiescent current compares operating current low a lot of usually, the required measurement accuracy is higher and the voltage amplification factor of first current detection chip compares the big of second current detection chip, therefore can realize quiescent current's high accuracy measurement, simultaneously, the measurement accuracy of the operating current of power amplifier tube power supply route also can obtain better satisfaction, rather than the current detection of the whole process of power amplifier tube power supply route is accomplished to a current detection chip, the problem that traditional power amplifier current detection mode detection precision is not high has effectively been solved, the effect of power amplifier current detection precision has been reached and has been promoted by a wide margin.
Drawings
Fig. 1 is a block diagram of a radio frequency link of a conventional power amplifier module;
FIG. 2 is a schematic diagram of a relationship curve between voltage and current of a conventional power amplifier current detection;
fig. 3 is a schematic diagram of a first structure of an auxiliary control circuit of a power amplifier module according to an embodiment;
FIG. 4 is a schematic diagram illustrating a voltage-current relationship curve of the power amplifier current detection according to the present application in one embodiment;
fig. 5 is a schematic diagram of a second structure of an auxiliary control circuit of the power amplifier module in an embodiment;
fig. 6 is a schematic diagram of a third structure of an auxiliary control circuit of a power amplifier module according to an embodiment;
fig. 7 is a fourth schematic diagram of an auxiliary control circuit of the power amplifier module according to an embodiment;
fig. 8 is a fifth structural diagram of an auxiliary control circuit of the power amplifier module according to an embodiment;
fig. 9 is a schematic structural diagram of a power amplifier current detection circuit portion of the communication device in an embodiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
It is to be noted that, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
The power amplifier module mainly comprises a radio frequency link and an auxiliary control circuit. The radio frequency link part is mainly composed of gain attenuation circuits, pre-pushing stage low-power amplifier tubes, pushing stage middle-power amplifier tubes, final-stage high-power amplifier tubes and other power amplifier devices, isolators and the like in a cascade mode. According to the requirement of the gain of the power amplifier module, two or more pre-pushing stages can be used for cascading when the gain requirement is higher. The auxiliary control circuit has any one or more 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. Fig. 1 shows a block diagram of a radio frequency link of one common power amplifier module.
Generally, the main core device of the power amplifier module is a power amplifier tube. The power amplifier tube has various types, and the common power amplifier tube is made of materials such as LDMOS or GaN and the like. Gain G and saturation power P of power amplifier tubesatThe gain of the common power amplifier tube is 17dB-22dB in different grades. Saturation power P of power amplifier tubesatThere are different grades of 10W, 20W, 50W, 100W or 400W. Engineers can select different power amplification tubes according to actual application requirements so as to achieve the purpose of power amplification and realize corresponding link functions.
In order to amplify an input signal Pin to a gain and power value required by the actual use of the whole communication system, power amplification tubes with different power levels are generally used in a cascade manner to amplify the signal, and the gain and saturation power P of the power amplification tubes are reasonably utilizedsatThe purpose of (1). For the power amplifier tube, two important indexes need attention in practical use conditions, namely quiescent current and working 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 (i.e. the gate voltages VGS1 and VGS2 shown in fig. 1) of the power amplifier tube, and the quiescent current reflects the initial operating state and the quiescent operating point of the power amplifier tube, and different saturation powers PsatThe quiescent currents of the power amplifier tubes are different. In general, the saturation power PsatThe lower the quiescent current of the power amplifier tube, e.g. 20W saturation power PsatThe quiescent current of (1) is about 100 mA-200 mA, and the saturation power P of 400W issatThe quiescent current of (2) is about 1000 mA-2000 mA.
The operating current is the dynamic current during operation compared to the quiescent current. The working current of the power amplifying tube is related to the signal power entering the power amplifying tube, and the efficiency and the working state of the power amplifying tube are reflected. Whether the power amplifier tube is in a normal working state or not can be judged through the working current, whether the efficiency is higher or lower, and the working currents of the power amplifier tubes with different efficiencies and different output powers are different. Taking the power amplifier module outputting 80W radio frequency power when supplying power at 28V as an example, the approximate working current range is 8A-10A.
In a traditional application occasion, the quiescent current of the power amplifier tube is generally read through a current detection chip so as to automatically adjust and set the grid voltage of the power amplifier tube for the power amplifier module; and reading the working current of the power amplifier tube through the current detection chip so as to calculate the efficiency of the power amplifier module and judge whether the power amplifier module is abnormal. Commonly used current detection chips are the INA138 and INA168 series of Texas Instruments (TI), MAX4173 and MAX4375 series of MAXIM, and ADM4073 series of Analog Devices (ADI). The current detection IC chip after the integration optimization has the characteristics of small volume, high precision, good performance and the like, and is widely applied to printed circuit boards.
In the application of the integrated current detection chip, no matter what kind of current detection chip, the integrated current detection chip mainly comprises the following three parts: the detection device comprises a detection resistor, a detection chip body and a detection voltage external amplifying circuit. The detection chip body processes the voltage drop through an internal precise differential amplification circuit, and then amplifies a detection voltage value obtained by the voltage drop to a proper value through a detection voltage external amplification circuit and outputs the detection voltage value.
In practical application, it is found that when the conventional current detection chip is used in a power amplifier module, the difference between the quiescent current and the operating current of the power amplifier tube is large, for example, the range of the quiescent current is 100mA to 1200mA, and the range of the operating current is 0A to 10A. The detection voltage finally output by the detection voltage external amplifying circuit is converted into a corresponding digital signal by an AD (analog-to-digital conversion) chip, enters a main control chip of an MCU (microprogrammed control unit) or other programmable logic circuits and the like, and is processed by the main control chip, or is directly converted by an AD (analog-to-digital conversion) port arranged in the main control chip. Generally, the maximum detection voltage of the analog input of the AD port cannot exceed 3.3V or 5V, and thus, in practical use, a problem exists, in which it is assumed that the maximum detectable analog voltage of the main control chip of the power amplifier module is 5V, the maximum operating current of the power amplifier module is 10A, the quiescent current of the push stage is 150mA, and the quiescent current of the final stage is 600 mA. When a current detection chip is used to perform current detection in cooperation with a main control chip, a detection voltage Vo output by the current detection chip and a detection current I measured and calculated by the main control chip based on the detection voltage Vo are in a linear proportional relationship, as shown in fig. 2.
When the current I of the current path to be detected is 10A, the detection voltage output by the current detection chip is 5.0V, and when I is 5A, the detection voltage Vo is 2.5V, that is, 1A corresponds to 500mV, and 10mA corresponds to 5mV current detection accuracy, and this current detection accuracy is fixed. In the practical use of the power amplifier module, the current detection precision is required to be higher when the quiescent current is detected, for example, the precision that 10mA corresponds to 10mV can be achieved, so that the quiescent current is accurately detected, and the accurate quiescent current control of the grid voltage of a power amplifier tube on the power amplifier module is facilitated; when the working current is detected, the detection accuracy of 1A corresponding to 50mV (10mA corresponding to 0.5mV) can also meet the actual use requirement, such as current alarm. That is to say, on the power amplifier module, the detection precision that requires is higher when the current detection chip detects quiescent current, and can be on the low side to the required detection precision of working current detection time, and this can't accomplish in traditional current detection mode.
Referring to fig. 3 and 4, in order to solve the problem of low detection precision in the power amplifier current detection mode, in an embodiment, an auxiliary control circuit 100 of a power amplifier module is provided, which includes a main control chip 201, a first current detection chip 12, and a second current detection chip 14. The amplification factor of the output voltage of the first current detection chip 12 is larger than that of the second current detection chip 14. The detection input end of the first current detection chip 12 is used for accessing a static voltage of a power supply path of a power amplifier tube of the power amplifier module. The detection output end of the first current detection chip 12 is electrically connected to the main control chip 201 of the power amplifier module. The first current detection chip 12 is configured to differentially amplify the static voltage and output the amplified voltage to the main control chip 201. The detection input end of the second current detection chip 14 is used for accessing the working voltage of the power supply path of the power amplifier tube. The detection output end of the second current detection chip 14 is electrically connected to the main control chip 201. The second current detection chip 14 is configured to differentially amplify the working voltage and output the amplified working voltage to the main control chip 201.
It is understood that the first current detection chip 12 and the second current detection chip 14 are current detection chips known in the art, and the circuit structures of the chips are shown in fig. 1. The detection accuracy of the first current detection chip 12 and the second current detection chip 14 is related to the amplification factor of the output voltage, that is, the larger the amplification factor of the output voltage is, the higher the accuracy of the current detection chips is. The amplification factor of the output voltage is determined by the resistance of the current detection resistor R14 of the current detection chip and the resistance of the resistor R31 in the external amplification circuit, and the specific resistance can be selected according to the detection precision required in practical application. Therefore, the current detection is carried out on the power amplifier module by adopting two paths of current detection chips, wherein the detection precision of the first current detection chip 12 for detecting the quiescent current is higher than that of the second current detection chip 14 for detecting the working current, so that the higher precision required by the quiescent current detection can be ensured, and the grid voltage control precision of the power amplifier tube of the power amplifier module is improved.
The power supply path of the power amplifier tube of the power amplifier module also refers to a path for a driving source of the power amplifier module to supply power to the push-stage power amplifier tube and the final-stage power amplifier tube. The current detecting resistor in the detection input terminal of the first current detecting chip 12 is electrically connected to the power amplifier tube power supply path in a conventional access manner in the art, so that the current in the power amplifier tube power supply path can flow through the current detecting resistor in the detection input terminal of the first current detecting chip 12, and thus the first current detecting chip 12 can detect the voltage corresponding to the flowing quiescent current, that is, the quiescent voltage, on the current detecting resistor thereof. The circuit connection mode of the detection input end of the second current detection chip 14 connected to the power supply path of the power amplifier tube can be understood in the same way.
The main control chip 201 is an existing MCU or other type of control chip on the power amplifier module in the field, and has a radio frequency link control function, a current measurement function, and a control function required by other power amplifier modules. The main control chip 201 may be a control chip carried by the auxiliary control circuit, a master control unit arranged on the power amplifier module, or an auxiliary control chip independently arranged outside. The main control chip 201 is configured to measure and calculate a corresponding quiescent current after receiving the quiescent voltage output by the first current detection chip 12, so as to automatically control the gate voltage adjustment of the power amplifier tube; and the second current detection chip 14 is used for receiving the working voltage output by the second current detection chip and then calculating the corresponding working current so as to complete the working current monitoring and early warning of the power amplifier module. It should be noted that, for convenience of description, the drawings are given by taking the current detection chip of the INA138 series as an example, and other types of current detection chips can be similarly understood.
Specifically, when the driving source of the power amplifier module starts to supply power for driving, the current sensing resistor in the detection input terminal of the first current detection chip 12 and the current sensing resistor in the detection input terminal of the second current detection chip 14 will generate corresponding voltage drops, that is, static voltages. The first current detection chip 12 differentially amplifies the static voltage to a voltage input requirement suitable for the main control chip 201 through a self internal precise differential amplification circuit, and then outputs the amplified voltage to the main control chip 201. The main control chip 201 automatically reads the static voltage output by the first current detection chip 12 with higher detection accuracy, so that the static voltage is measured and calculated to obtain the static current of the initial state when the power amplifier module starts to work, so as to determine whether the static current is consistent with the set static current (or called standard static current). If the difference is not satisfied, the main control chip 201 may directly or indirectly control the gate voltage of the power amplifier tube of the power amplifier module to adjust the quiescent current to a predetermined value.
When it is determined that the quiescent current matches the set quiescent current, the main control chip 201 automatically reads the working voltage output by the second current detection chip 14 whose detection accuracy is lower than that of the first current detection chip 12, that is, the working voltage is differentially amplified by the second current detection chip 14 through its internal precise differential amplification circuit to a working voltage suitable for the voltage input requirement of the main control chip 201. The main control chip 201 can measure and calculate the corresponding working current based on the working voltage output by the second current detection chip 14 in real time during the working period after the power amplifier module is normally started, so as to determine whether the working current is over-current, if so, the power amplifier current alarm function can be automatically completed, and if not, the working current of the power amplifier module can be continuously monitored or the working current of the power amplifier module can be displayed in real time with a equipped display unit.
Through the two paths of current detection chips, when the power amplifier tube power supply path of the power amplifier module has low current, the first current detection chip 12 and the main control chip 201 are adopted to detect the static current, so that the detection precision of the static current is higher, and the static current control of the grid voltage of the power amplifier tube on the power amplifier module is more facilitated. When the power supply path of the power amplifier tube of the power amplifier module is high current, the second current detection chip 14 and the main control chip 201 are used for detecting the working current, which is more suitable for the situation of low detection precision when the working current is larger during alarming. Therefore, the whole power amplifier current detection has higher precision in low current (quiescent current) and lower precision in high current (working current), and can meet the practical application requirements of low current and high current. Two current detection chips with different amplification factors of detected voltage are used, the first current detection chip 12 with high precision is required to have large amplification factor of the detected voltage, the second current detection chip 14 with low detection precision is required to have small amplification factor of the detected voltage, and the detection processing of power amplifier current is completed in cooperation with the main control chip 201, so that the purpose of variable current detection precision is realized, and the current detection chip can be used in different application scenes. The detection accuracy of the auxiliary control circuit 100 of the power amplifier module is shown in fig. 4, wherein 01 represents a detection accuracy curve of the first current detection chip 12, and 02 represents a detection accuracy curve of the second current detection chip 12.
The auxiliary control circuit 100 of the power amplifier module applies two current detection chips with different voltage amplification factors to the power amplifier module, wherein the first current detection chip 12 is used for detecting the static voltage of the power supply path of the power amplifier tube, so that the main control chip 201 can calculate the static current of the power amplifier module from the static voltage. The second current detection chip 14 is configured to detect a working voltage of a power supply path of the power amplifier, so that the main control chip 201 can calculate a working current of the power amplifier module according to the working voltage. Because quiescent current compares operating current a lot of lowly usually, required measurement accuracy is higher and the voltage amplification factor of first current detection chip 12 compares second current detection chip 14 big, therefore can realize quiescent current's high accuracy measurement, simultaneously, the measurement accuracy of the operating current of power amplifier tube power supply route also can obtain better satisfaction, rather than accomplish the current detection of power amplifier tube power supply route overall process by a current detection chip, the problem that traditional power amplifier current detection mode detection precision is not high has effectively been solved, the effect that has promoted power amplifier current detection precision by a wide margin has been reached.
In one embodiment, the detection input terminal of the first current detection chip 12 and the detection input terminal of the second current detection chip 14 are connected in series to the power supply path of the power amplifier tube through the same current detection resistor.
It is understood that the first current detecting chip 12 and the second current detecting chip 14 in the above embodiments may be respectively connected to the power amplifier supply path through the current detecting resistors in the respective detecting input terminals, while in the present embodiment, the detecting input terminal of the first current detecting chip 12 and the detecting input terminal of the second current detecting chip 14 may share one current detecting resistor, and are not separately connected to the power amplifier supply path.
Specifically, two current detection chips of different resistance values R31 are selected, so that in two current detection chips sharing one current detection resistor, the amplification factor of the output voltage of the first current detection chip 12 is greater than that of the output voltage of the second current detection chip 14. Therefore, when the power amplifier module is in the quiescent current working phase of low current, the quiescent voltage generated by the shared current-detecting resistor is detected with high precision by the first current-detecting chip 12 and amplified and output to the main control chip 201 for processing, so that the main control chip 201 can accurately regulate and control the gate voltage of the power amplifier tube based on the high-precision quiescent current. When the power amplifier module is in the working stage of large current, the working voltage generated on the shared current detecting resistor is detected by the second current detecting chip 14 and amplified and output to the main control chip 201 for processing, so that the main control chip 201 can perform power amplifier current alarm and monitoring based on the relatively low-precision working current.
Through the design that the first current detection chip 12 and the second current detection chip 14 share one current detection resistor, the current design and manufacturing cost and the required PCB layout space can be further saved while the normal detection function of the power amplifier current in two stages is ensured. The current detection resistor belongs to a high-power precision resistor, the cost is high, the design of sharing one current detection resistor can effectively save the cost, and simultaneously, the circuit structure can be simplified, so that the overall reliability of the circuit is improved.
Referring to fig. 5, in an embodiment, the auxiliary control circuit 100 of the power amplifier module further includes a first voltage stabilizing circuit 16. The detection output end of the first current detection chip 12 is electrically connected to the main control chip 201 through the first voltage regulator circuit 16.
It is understood that the first voltage regulating circuit 16 is a circuit element or a circuit module with voltage stabilizing and amplitude limiting functions, and may be, but is not limited to, various types of voltage regulating devices or modules in the art. The voltage-stabilizing voltage of the first voltage-stabilizing circuit 16 can be determined according to the allowable input voltage of the AD device, the main control chip 201, and the like in the practical application scene, as long as it can effectively prevent the damage of the connected AD device, the main control chip 201, and the like caused by the excessively large static voltage correspondingly output by the first current detection chip 12 when the detected power amplifier current is large.
Specifically, since the detection accuracy of the first current detection chip 12 is higher, the quiescent voltage detected and output by the first current detection chip 12 is much larger than the operating voltage detected and output by the second current detection chip 14 under the same detection current, which is more obvious under the condition of large current. Therefore, a first voltage regulator circuit 16 is added at the detection output terminal of the first current detection chip 12 as an output voltage overvoltage protection circuit. For example, if the maximum input voltage of the AD device and the pin of the main control chip 201 is 5V, a 5V first regulator circuit 16 may be selected. When the output voltage is greater than 5V, the voltage regulator device in the first voltage regulator circuit 16 is turned on in the opposite direction, so that the maximum value of the output voltage does not exceed 5V, and the circuit device is protected.
By applying the first voltage stabilizing circuit 16, the circuit device can be effectively prevented from being damaged due to overvoltage generated when large current occurs in the power amplifier current detection process, and the purpose of further improving the circuit reliability is achieved.
Referring to fig. 6, in an embodiment, the auxiliary control circuit 100 of the power amplifier module further includes a second voltage stabilizing circuit 18. The detection output end of the second current detection chip 14 is electrically connected to the main control chip 201 through the second voltage regulator circuit 18.
It is understood that the second voltage regulating circuit 18 is a circuit element or a circuit module with voltage stabilizing and amplitude limiting functions, and may be, but is not limited to, various types of voltage regulating devices or modules in the art. The voltage-stabilizing voltage of the second voltage-stabilizing circuit 18 can be determined according to the allowable input voltage of the AD device, the main control chip 201, and the like in the practical application scene, as long as it can effectively prevent the device, such as the AD device, the main control chip 201, and the like, connected to the second current detection chip 14 from being damaged due to the excessively large output working voltage when the detected power amplifier current is large.
Specifically, in the above embodiment, the second current detection chip 14 with a suitable output voltage amplification factor may be selected according to the maximum current of the power amplifier module, so that the working voltage output by the second current detection chip 14 when the current is large may not exceed the maximum voltage detection range of the main control chip 201. The detection output terminal of the second current detection chip 14 can save the access of the voltage stabilization protection circuit for cost saving. In this embodiment, the second voltage stabilizing circuit 18 is additionally arranged between the detection output end of the second current detection chip 14 and the main control chip 201, so that overvoltage protection during the detection of the working current can be better provided, and damage to the main control chip 201 due to an emergency overvoltage condition is avoided.
By applying the second voltage stabilizing circuit 18, the power amplifier can be more effectively prevented from generating overvoltage to damage circuit devices when large current occurs in the power amplifier current detection process, and the purpose of further improving the circuit reliability is achieved.
In one embodiment, as shown in FIG. 5 or FIG. 6, the first stabilizing circuit 16 is a zener diode D1. The second stabilizing circuit 18 is a zener diode D2. The anode of the zener diode D1 is grounded. The cathode of the zener diode D1 is electrically connected between the detection output terminal of the first current detection chip 12 and the main control chip 201. The anode of the zener diode D2 is grounded. The cathode of the zener diode D2 is electrically connected between the detection output terminal of the second current detection chip 14 and the main control chip 201.
It can be understood that the zener diode D1 and the zener diode D2 may be the same type of zener diode with different models, or the same type of zener diode with the same model, and may be determined according to the peak magnitude of the power amplifier current and the maximum voltage detection range of the main control chip 201 in practical application.
Specifically, a zener diode D1 is added to the detection output terminal of the first current detection chip 12 to serve as an output voltage overvoltage protection circuit. When the voltage output by the first current detection chip 12 exceeds the maximum voltage detection range of the main control chip 201, the zener diode D1 is turned on in the reverse direction, so that the maximum value of the output voltage does not exceed the maximum voltage detection range of the main control chip 201, thereby playing a role of protecting circuit devices.
The output voltage overvoltage protection circuit is formed by adding a voltage stabilizing diode D2 to the detection output end of the second current detection chip 14. When the voltage output by the second current detection chip 14 exceeds the maximum voltage detection range of the main control chip 201, the zener diode D2 is turned on in the reverse direction, so that the maximum voltage output does not exceed the maximum voltage detection range of the main control chip 201, and the circuit device is protected.
By applying the zener diode D1 and the zener diode D2, the circuit reliability of the auxiliary control circuit 100 of the power amplifier module can be effectively improved, and meanwhile, the required circuit protection function can be provided by adding the access of one or two zener diodes, so that the circuit structure is simplified and the cost is low.
Referring to fig. 7, in an embodiment, the auxiliary control circuit of the power amplifier module further includes a filter capacitor C1 and a filter capacitor C2. One end of the filter capacitor C1 is electrically connected between the detection output end of the first current detection chip 12 and the main control chip 201. The other end of the filter capacitor C1 is grounded. One end of the filter capacitor C2 is electrically connected between the detection output end of the second current detection chip 14 and the main control chip 201. The other end of the filter capacitor C2 is grounded.
It can be understood that, in this embodiment, a filter capacitor C1 may be further connected between the detection output terminal of the first current detection chip 12 and the main control chip 201 to filter noise on the detection output terminal of the first current detection chip 12, so that the output dc voltage is more stable. A filter capacitor C2 is connected between the detection output terminal of the second current detection chip 14 and the main control chip 201 to filter noise on the detection output terminal of the second current detection chip 14, so that the output dc voltage is more stable.
The parameter specifications of the filter capacitor C1 and the filter capacitor C2 can be selected according to the power supply mode of the power amplifier module in practical application, the output characteristic of the current detection chip and the like, and only the required clutter filtering function can be effectively provided. Through using foretell filter capacitor C1 and filter capacitor C2, between first current detection chip 12 and main control chip 201 to and provide the filtering action between second current detection chip 14 and main control chip 201, make the output voltage of two current detection chips more steady, eliminate the interference of clutter to power amplifier current detection, thereby can further promote the detection precision of power amplifier current.
Referring to fig. 8, in an embodiment, the auxiliary control circuit 100 of the power amplifier module further includes an automatic gate voltage adjusting circuit 20. The input terminal of the gate voltage automatic adjusting circuit 20 is used for electrically connecting the main control chip 201. The gate voltage automatic adjusting circuit 20 is configured to adjust a gate voltage of a power amplifier tube of the power amplifier module after receiving the quiescent current adjusting signal output by the main control chip 201.
It is understood that the gate voltage automatic adjusting circuit 20 is a power amplifier tube gate voltage adjusting circuit known in the art. Specifically, in the working process of the power amplifier module, after the static voltage detected and output by the first current detection chip 12 is differentially amplified to a proper voltage, the static voltage is subjected to noise filtering and voltage stabilizing processing by the filter capacitor C1 and the voltage stabilizing diode D1, and then enters the main control chip 201, for example, an MCU processing unit of the power amplifier module. The MCU processing unit detects and obtains corresponding quiescent current based on the input quiescent voltage, compares the quiescent current with the set quiescent current and judges whether the current quiescent current is correct or not. If not, the MCU processing unit will automatically generate a corresponding quiescent current adjustment signal and output the quiescent current adjustment signal to the gate voltage automatic adjustment circuit 20. After receiving the quiescent current adjustment signal, the gate voltage automatic adjustment circuit 20 adjusts the gate voltage of the corresponding power amplifier transistor according to the quiescent current adjustment signal. Thus, after the gate voltage is adjusted, the MCU processing unit performs the static current detection again based on the output static voltage detected by the first current detecting chip 12 until the static current corresponding to the output static voltage detected by the first current detecting chip 12 is consistent with the set static current or is within the allowed floating range of the set static current. If yes, the MCU processing unit receives the operating voltage from the second current detecting chip 14 and detects the operating current based on the operating voltage.
Through the cooperative application of the first current detection chip 12, the main control chip 201 and the gate voltage automatic adjustment circuit 20, the high-precision static current detection can be effectively realized, and simultaneously, the high-precision gate voltage automatic adjustment of the power amplifier tube can be realized.
In an embodiment, as shown in fig. 8, the auxiliary control circuit 100 of the power amplifier module further includes a power amplifier alarm circuit 22. The input end of the power amplifier alarm circuit 22 is used for electrically connecting the main control chip 201. The power amplifier warning circuit 22 is configured to perform an overcurrent warning on the working current of the power amplifier module after receiving the warning signal output by the main control chip 201.
It is understood that the power amplifier warning circuit 22 is a power amplifier warning circuit 22 provided in a conventional auxiliary control circuit in the art. Specifically, in the working process of the power amplifier module, the working voltage detected and output by the second current detection chip 14 is subjected to differential amplification to a proper voltage, and then enters the main control chip 201, such as the MCU processing unit of the power amplifier module, after being subjected to clutter filtering and voltage stabilizing processing by the filter capacitor C2 and the zener diode D2. The MCU processing unit detects and obtains corresponding working current based on the input working voltage, compares the working current with the set working current (or called standard dynamic current), and judges whether the current working current is overlarge or not. If yes, the MCU processing unit will automatically generate a corresponding alarm signal and output the alarm signal to the power amplifier alarm circuit 22. After receiving the alarm signal, the power amplifier alarm circuit 22 may perform a working current over-current alarm on the power amplifier module according to the alarm signal, for example, upload 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 master control system. If not, the MCU processing unit will continue to receive and detect the working current based on the working voltage output by the second current detecting chip 14, or output the data of the working current to the outside for the external device to perform linkage.
For easier understanding, in the power amplifier module, the quiescent current and the operating current are both currents in a path powered by the same driving source, and the quiescent current 750mA and the operating current 9.5A are taken as examples for explanation:
the first current detection chip 12 is mainly responsible for detecting the quiescent voltage corresponding to the quiescent current, and the required detection precision is higher, that is, the amplification factor of the detected voltage is larger. The second current detection chip 14 is mainly responsible for detecting the working voltage corresponding to the working current, and the required detection relative precision is low, that is, the amplification factor of the detection voltage is small. The maximum withstand input voltage of the MCU processing unit is 5V, and the current sensing resistor R14 is selected to be 0.05 Ω.
The resistor R31 of the detection voltage external amplification circuit of the first current detection chip 12 is a 400k Ω resistor. Then, the relationship of the output voltage of the first current detection chip 12 to the current: vo1 ═ I0.05 ═ 400k/5k ═ I4. When I is 1A, Vo1 is 4.0V, where I denotes a current flowing through the current detection resistor R14.
The resistor R31 of the detection voltage external amplifier circuit of the second current detection chip 14 is a 40k Ω resistor. Then, the output voltage of the second current detection chip 14 has a relationship with the current: vo2 ═ I0.05 ═ 40k/5k ═ I0.4. When I is 1A, Vo2 is 0.4V.
When the quiescent current is 750mA, Vo1 is 4 × 0.75 — 3.0V; vo2 ═ 0.4 ═ 0.75 ═ 0.3V; at this time, the MCU processing unit selects only the voltage Vo1 for processing, and performs the gate voltage automatic adjustment control on the gate voltage automatic adjustment circuit 20. The Vo2 voltage is not processed.
When the working current is 9.5A, Vo1 ═ 4 × 9.5 ═ 38V; vo2 ═ 0.4 × 9.5 ═ 3.8V. In order to prevent the gate voltage VGS1 from being too large when a large current flows, the first voltage regulator circuit 16 (the main device is a zener diode D1, also called a zener diode D1) electrically connected to the first current detection chip 12 is added, and the gate voltage VGS1 passing through the first voltage regulator circuit 16 does not exceed 5V at most, so that the reliability of the circuit can be improved. In this example, the MCU control unit functions to detect the output voltage values Vo1 and Vo2 by reading the first current detecting chip 12 and the second current detecting chip 14, and to use Vo1 and Vo2 in the different power amplifier detection control processes described above, respectively, according to the comparison results corresponding to the voltage values Vo1 and Vo 2.
Through the cooperative application of the first current detection chip 12, the second current detection chip 14, the main control chip 201 and the power amplifier warning circuit 22, the accurate detection of the working current can be effectively realized, and meanwhile, the overcurrent warning function of the working current of the power amplifier module is reliably realized.
In an embodiment, a power amplifier module is further provided, which includes the auxiliary control circuit 100 of the power amplifier module.
It can be understood that, for the explanation of the auxiliary control circuit 100 of the power amplifier module in this embodiment, the same principle can be understood by referring to the relevant explanations in each embodiment of the auxiliary control circuit 100 of the power amplifier module, and repeated descriptions are not repeated here.
Foretell power amplifier module, the combination through main control chip 201 and above-mentioned power amplifier module's auxiliary control circuit 100 is used, make power amplifier current detection in-process current detection precision variable, can realize quiescent current's high accuracy measurement, simultaneously, power amplifier tube power supply path's operating current's measurement accuracy also can obtain better satisfaction, rather than accomplishing the current detection of power amplifier tube power supply path overall process by a current detection chip, the problem that traditional power amplifier current detection mode detection precision is not high has effectively been solved, the effect that has promoted power amplifier current detection precision by a wide margin has been reached.
In an embodiment, a communication device 300 is further provided, which includes the power amplifier module.
It is understood that the communication device 300 may be various devices applied to a power amplifier module in a communication system for performing power amplifier current detection and alarm, as will be understood by those skilled in the art. The communication device may further include other components besides the power amplifier module, such as, but not limited to, a memory device, a transceiver antenna, a data conversion circuit, and the like.
The communication equipment 300 can enable the current detection precision to be variable in the power amplifier current detection process by applying the power amplifier module, can realize high-precision measurement of quiescent current, and meanwhile, the measurement precision of the working current of the power amplifier tube power supply path can be well met, so that the problem that the detection precision of the traditional power amplifier current detection mode is not high is effectively solved, and the effect of greatly improving the power amplifier current detection precision is achieved.
Referring to fig. 9, in an embodiment, the communication device 300 further includes a current display device 31. The current display device 31 is electrically connected to the main control chip 201 of the power amplifier module. The display device is used for displaying the working current of the power amplifier module after receiving the working current signal output by the main control chip 201. The working current is the current corresponding to the working voltage of the power supply circuit of the power amplifier tube of the power amplifier module.
It is understood that the current display device 31 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 control input function. The current display device 31 and the power amplifier module may be independently disposed on the communication device 300 in the form of discrete components, or may be integrally disposed in an integrated packaging manner, and the specific disposition may be determined according to the size and shape of the current display device 31, and the auxiliary function (for example, touch input, key input, or floating operation input) provided therein.
Specifically, in the working process of the power amplifier module, after the working voltage detected and output by the second current detection chip 14 is differentially amplified to a proper voltage, the working voltage is subjected to clutter filtering and voltage stabilizing processing by the filter capacitor C2 and the voltage stabilizing diode D2 and then enters the MCU processing unit. The MCU processing unit detects and obtains corresponding working current based on the input working voltage, compares the working current with the set working current (or called standard dynamic current), and judges whether the current working current is overlarge or not. If yes, the MCU processing unit can link the power amplifier warning circuit 22 to perform overcurrent warning on the working current of the power amplifier module. If not, the MCU processing unit will continue to receive and detect the operating current based on the operating voltage output by the second current detecting chip 14, and output the real-time operating current to the current display device 31. The current display device 31 may display real-time working current data through a numerical value or a curve graph, or a numerical value and a curve graph, so that an operation and maintenance person can know the working current of the power amplifier module in the communication device 300 at any time, thereby determining the working state of the power amplifier module.
Through the combined application of the power amplifier module and the current display device 31, the real-time display function of the working current in the working current detection process of the power amplifier module can be realized.
In an embodiment, the communication device 300 is any one of a repeater device, a radio remote device, a track power amplifier device, an integrated power amplifier and a receiver.
It can be understood that the communication device 300 using the power amplifier module may be any one of a repeater device, a radio frequency remote device, a track power amplifier device, an integrated power amplifier and a receiver in the field, so as to improve the power amplifier current detection precision of the device, thereby more accurately controlling the gate voltage of the power amplifier tube, and completing the functions of power amplifier alarm or current display, etc. It will be understood by those skilled in the art that the foregoing list is only a few common communication devices 300, and the power amplifier module described above can also be applied to other devices that need to have a power amplifier current detection function.
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above examples only show some embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (11)

1. An auxiliary control circuit of a power amplifier module is characterized by comprising a main control chip, a first current detection chip and a second current detection chip, wherein the amplification factor of the output voltage of the first current detection chip is greater than that of the output voltage of the second current detection chip;
the detection input end of the first current detection chip is used for accessing a static voltage of a power supply channel of a power amplifier tube of a power amplifier module, the detection output end of the first current detection chip is electrically connected with the main control chip, and the first current detection chip is used for performing differential amplification on the static voltage and then outputting the amplified static voltage to the main control chip;
the detection input end of the second current detection chip is used for accessing the working voltage of the power supply passage of the power amplifier tube, the detection output end of the second current detection chip is electrically connected with the main control chip, and the second current detection chip is used for carrying out differential amplification on the working voltage and then outputting the working voltage to the main control chip.
2. The auxiliary control circuit of the power amplifier module according to claim 1, wherein the detection input terminal of the first current detection chip and the detection input terminal of the second current detection chip are connected in series to the power supply path of the power amplifier tube through a same current detection resistor.
3. The auxiliary control circuit of the power amplifier module according to claim 1 or 2, further comprising a first voltage stabilizing circuit, wherein the detection output terminal of the first current detection chip is electrically connected to the main control chip through the first voltage stabilizing circuit.
4. The auxiliary control circuit of the power amplifier module according to claim 3, further comprising a second voltage stabilizing circuit, wherein the detection output terminal of the second current detection chip is electrically connected to the main control chip through the second voltage stabilizing circuit.
5. The auxiliary control circuit of the power amplifier module according to claim 4, wherein the first voltage stabilizing circuit is a zener diode D1, and the second voltage stabilizing circuit is a zener diode D2;
the anode of the zener diode D1 is grounded, and the cathode of the zener diode D1 is electrically connected between the detection output end of the first current detection chip and the main control chip;
the anode of the zener diode D2 is grounded, and the cathode of the zener diode D2 is electrically connected between the detection output end of the second current detection chip and the main control chip.
6. The auxiliary control circuit of the power amplifier module of claim 5, further comprising a filter capacitor C1 and a filter capacitor C2;
one end of the filter capacitor C1 is electrically connected between the detection output end of the first current detection chip and the main control chip, and the other end of the filter capacitor C1 is grounded;
one end of the filter capacitor C2 is electrically connected between the detection output end of the second current detection chip and the main control chip, and the other end of the filter capacitor C2 is grounded.
7. The auxiliary control circuit of the power amplifier module according to any one of claims 4 to 6, further comprising a gate voltage automatic adjusting circuit, wherein an input end of the gate voltage automatic adjusting circuit is electrically connected to the main control chip;
the grid voltage automatic adjusting circuit is used for adjusting the grid voltage of the power amplification tube of the power amplification module after receiving the static current adjusting signal output by the main control chip.
8. The auxiliary control circuit of the power amplifier module according to claim 7, further comprising a power amplifier alarm circuit, wherein an input terminal of the power amplifier alarm circuit is electrically connected to the main control chip, and the power amplifier alarm circuit is configured to perform an overcurrent alarm on the working current of the power amplifier module after receiving the alarm signal output by the main control chip.
9. A power amplifier module comprising the auxiliary control circuit of any one of claims 1 to 6.
10. A communication device comprising the power amplifier module of claim 9.
11. The communication device according to claim 10, further comprising a current display device electrically connected to the main control chip of the power amplifier module;
the display device is used for displaying the working current of the power amplification module after receiving the working current signal output by the main control chip; the working current is the current corresponding to the working voltage of the power supply channel of the power amplifier tube of the power amplifier module.
CN201911289335.9A 2019-12-13 2019-12-13 Auxiliary control circuit of power amplifier module, power amplifier module and communication equipment Pending CN111123772A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911289335.9A CN111123772A (en) 2019-12-13 2019-12-13 Auxiliary control circuit of power amplifier module, power amplifier module and communication equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911289335.9A CN111123772A (en) 2019-12-13 2019-12-13 Auxiliary control circuit of power amplifier module, power amplifier module and communication equipment

Publications (1)

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CN111123772A true CN111123772A (en) 2020-05-08

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