CN211296179U - Voltage clamping circuit and power amplifier protection device - Google Patents
Voltage clamping circuit and power amplifier protection device Download PDFInfo
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- CN211296179U CN211296179U CN201922250824.5U CN201922250824U CN211296179U CN 211296179 U CN211296179 U CN 211296179U CN 201922250824 U CN201922250824 U CN 201922250824U CN 211296179 U CN211296179 U CN 211296179U
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Abstract
The utility model provides a voltage clamping circuit and power amplifier protection device: the circuit comprises a voltage stabilization control module, a first resistor, a second resistor and a first capacitor; one end of the first resistor is used as the input end of the voltage clamping circuit and is used for inputting external voltage into the voltage clamping circuit, and the other end of the first resistor is electrically connected with one end of the first capacitor, one end of the second resistor and the first port of the voltage stabilization control module; the other end of the first capacitor and the other end of the second resistor are grounded; and the second port of the voltage stabilization control module is grounded, and the third port of the voltage stabilization control module is used as the output end of the voltage clamping circuit and used for outputting voltage. The utility model discloses a voltage clamp circuit that voltage stabilization control module constitutes effectively limits the bias voltage who exports power amplifier, avoids power amplifier's bias voltage too high, the electric current too big and lead to power amplifier to burn out; and the circuit design complexity is low, the occupied space is small, software program intervention is not needed, and the actual use and maintenance are convenient.
Description
Technical Field
The utility model relates to the field of communication technology, in particular to voltage clamping circuit and power amplifier protection device.
Background
The power amplifier is called power amplifier for short, and amplifies small signals in the base station, which is an essential part of communication equipment. In practical application, once the power amplifier is damaged, no signal is output from the whole base station system, and the base station system is in a paralysis state, which seriously affects normal communication of users in the coverage area of the base station. Therefore, the power amplifier is one of the key components of the base station system, and is very important for protecting the power amplifier.
For power amplifier protection of a base station system, considerable research has been carried out in the industry, and certain application effects are obtained, for example, a power amplifier protection circuit mentioned in patent CN205509988U, the circuit includes a GP circuit, an over-current detection circuit and a signal compression circuit, which compresses a signal output when detecting an over-current signal through the over-current detection circuit, and if the over-current continues, the power amplifier is muted to realize protection of the power amplifier. However, the existing power amplifier protection circuit has more related circuit modules, so that the setting space of the circuit is increased, and the complexity of the circuit design is increased.
SUMMERY OF THE UTILITY MODEL
The utility model discloses an overcome current power amplifier protection circuit and exist to occupy the technical defect that sets up space, circuit design are complicated, provide a voltage clamping circuit and power amplifier protection device.
In order to achieve the above object, the present application provides a voltage clamp circuit including a voltage stabilization control module U1, a first resistor R1, a second resistor R2, and a first capacitor C1; wherein:
one end of the first resistor R1 is used as an input end of the voltage clamping circuit, and is used for inputting an external voltage into the voltage clamping circuit, and the other end of the first resistor R1 is electrically connected with one end of the first capacitor C1, one end of the second resistor R2, and the first port of the voltage stabilization control module U1;
the other end of the first capacitor C1 and the other end of the second resistor R2 are grounded;
and the second port of the voltage stabilizing control module U1 is grounded, and the third port of the voltage stabilizing control module U1 is used as the output end of the voltage clamping circuit and used for outputting voltage.
In the above scheme, the reference voltage V exists inside the voltage regulation control module U1refWhen the input voltage V of the voltage clamping circuitinLess than a reference voltage VrefThe output voltage of the voltage-clamping circuit, i.e. the bias voltage V of the input power amplifiergsIs directly equal to the input voltage Vin(ii) a When the input voltage V of the voltage clamping circuitinGreater than a reference voltage VrefThe output voltage of the voltage-clamping circuit, i.e. the bias voltage V of the input power amplifiergsComprises the following steps:
Vgs＝Vref(1+R1/R2)+Iref*R1
wherein, IrefRepresenting a reference voltage VrefThe current magnitude of the circuit; thus, for the bias voltage VgsThe clamping is realized, the bias voltage provided for the power amplifier is limited within a certain range, and the power amplifier is ensured not to be burnt out due to overlarge bias voltage; in practical use, only the first resistor R1 and the second resistor R2 need to be selected according to the safety value recommended by the bias voltage of the power amplifier in practical use, and the proper voltage stabilizing control module U1 is selected to provide the proper reference voltage, so as to ensure that the input voltage V is ensuredinThe requirement of the bias voltage of the power amplifier can be met, the power amplifier is prevented from being burnt out due to overlarge bias voltage, and the power amplifier is prevented from being incapable of meeting the requirement due to the fact that other indexes cannot be met due to the fact that the bias voltage is too low.
In order to achieve the above object, the present application further provides a power amplifier protection device, which includes a voltage clamping circuit, an input connection terminal and an output connection terminal; wherein:
the input end of the voltage clamping circuit inputs external voltage through the input wiring terminal;
and the output end of the voltage clamping circuit inputs voltage into the power amplifier through the output wiring terminal.
In the above scheme, for a power amplifier protection device provided for a power amplifier with a specific specification, the bias voltage of the power amplifier is limited within a certain range by a voltage clamping circuit arranged in the power amplifier protection device, so as to protect the power amplifier; meanwhile, the input wiring terminal and the output wiring terminal are arranged to facilitate the circuit connection of an external circuit and the power amplifier protection device.
Compared with the prior art, the utility model discloses technical scheme's beneficial effect is:
the utility model discloses a voltage clamping circuit that voltage stabilization control module constitutes, the bias voltage who restricts effectively to export power amplifier avoids because power amplifier's bias voltage is too high, and the electric current is too big and leads to power amplifier to burn out; and the circuit design complexity is low, the occupied space is small, software program intervention is not needed, and the actual use and maintenance are convenient.
The utility model discloses still constitute a power amplifier protection device through voltage clamp circuit, set up voltage clamp circuit to the power amplifier of certain specific specification effectively, within the certain limit with power amplifier's bias voltage restriction, realize the protection to power amplifier, the simple operation, occupation space is little, can be fine be used for large batch production.
Drawings
FIG. 1 is a schematic block diagram of a voltage clamp circuit in one embodiment;
fig. 2 is a schematic structural diagram of a power amplifier protection device in one embodiment;
FIG. 3 is a first schematic block diagram of an embodiment of a voltage output adjustable circuit;
FIG. 4 is a second schematic block diagram of a voltage output adjustable circuit in one embodiment;
FIG. 5 is a schematic block diagram of an embodiment of a power amplifier bias connection circuit;
wherein: 1. a voltage clamp circuit; 2. an input connecting terminal; 3. an output terminal; 4. a voltage output adjustable circuit; 5. the power amplifier is connected with the circuit in a biased mode.
Detailed Description
The drawings are for illustrative purposes only and are not to be construed as limiting the patent;
for the purpose of better illustrating the embodiments, certain features of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product;
it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
The technical solution of the present invention will be further explained with reference to the accompanying drawings and examples.
Fig. 1 is a schematic structural diagram of a voltage clamp circuit 1 in one embodiment, and as shown in fig. 1, the voltage clamp circuit 1 includes a voltage regulation control module U1, a first resistor R1, a second resistor R2, and a first capacitor C1; wherein:
one end of the first resistor R1 is used as an input end of the voltage clamp circuit 1, and is used for inputting an external voltage into the voltage clamp circuit 1, and the other end of the first resistor R1 is electrically connected with one end of the first capacitor C1, one end of the second resistor R2, and the first port of the voltage stabilization control module U1;
the other end of the first capacitor C1 and the other end of the second resistor R2 are grounded;
the second port of the voltage regulation control module U1 is grounded, and the third port of the voltage regulation control module U1 is used as the output end of the voltage clamp circuit 1 and is used for outputting voltage.
In the specific implementation process, a reference voltage V exists inside the voltage stabilization control module U1refWhen the input voltage V of the voltage clamp circuit 1inLess than a reference voltage VrefThe output voltage of the voltage clamp circuit 1, i.e. the bias voltage V of the input power amplifiergsIs directly equal to the input voltage Vin(ii) a When the input voltage V of the voltage clamp circuit 1inGreater than a reference voltage VrefTime, voltage clampingOutput voltage of circuit 1, i.e. bias voltage V of input power amplifiergsComprises the following steps:
Vgs＝Vref(1+R1/R2)+Iref*R1
wherein, IrefRepresenting a reference voltage VrefThe current magnitude of the circuit; thus, for the bias voltage VgsThe clamping is realized, the bias voltage provided for the power amplifier is limited within a certain range, and the power amplifier is prevented from being burnt due to overlarge bias voltage.
The voltage clamp circuit 1 of the embodiment only needs to select the first resistor R1 and the second resistor R2 according to the safety value recommended by actually using the bias voltage of the power amplifier, and select the proper voltage regulation control module U1 to provide the proper reference voltage, so as to ensure the input voltage VinThe requirement of the bias voltage of the power amplifier can be met, the power amplifier is prevented from being burnt out due to overlarge bias voltage, and the power amplifier is prevented from being incapable of meeting the requirement due to the fact that other indexes cannot be met due to the fact that the bias voltage is too low.
In the specific implementation process, the whole design complexity of the voltage clamping circuit 1 is low, the occupied space is small, software program intervention is not needed in the use process, and the practical use and maintenance are facilitated.
In a specific implementation process, the voltage regulation control module U1 may adopt a TL431 series voltage regulation chip, or may adopt a TL431 class voltage regulation chip.
Fig. 2 is a schematic structural diagram of a power amplifier protection device in an embodiment, and as shown in fig. 2, the power amplifier protection device may include a voltage clamp circuit 1, an input terminal 2 and an output terminal 3; wherein: the input end of the voltage clamping circuit 1 inputs external voltage through the input wiring terminal 2; the output end of the voltage clamping circuit 1 inputs voltage into the power amplifier through the output wiring terminal 3.
In the specific implementation process, the input wiring terminal 2 is connected with input voltage, and the input voltage passes through the voltage clamping circuit 1 and then is output to the power amplifier through the output wiring terminal 3, so that the input voltage is clamped.
In the implementation process, after the safety value recommended by the bias voltage of the power amplifier is determined, the resistance values of the first resistor R1 and the second resistor R2 on the voltage clamp circuit 1 and the reference voltage V can be determinedrefThe model of the regulator control module U1 is determined according to the difference between the value of (a) and the value of the bias voltage in the power amplifier actually used, and thus the specific structure of the voltage clamp circuit 1 is determined. Therefore, the voltage clamping circuit arranged in the power amplifier protection device can protect the power amplifier with a specific specification, and the input wiring terminal and the output wiring terminal are arranged to facilitate the circuit connection of an external circuit and the power amplifier protection device.
The power amplifier protection device also comprises a voltage output adjustable circuit 4; the input end of the voltage output adjustable circuit 4 is electrically connected with the input wiring terminal 2; the output end of the voltage output adjustable circuit 4 is electrically connected with the input end of the voltage clamping circuit 1 and is used for adjusting the input voltage of the voltage clamping circuit 1.
In the specific implementation process, the voltage output adjustable circuit 4 is arranged on the power amplifier protection device, so that on one hand, the input voltage can be controlled, on the other hand, the power amplifier protection device is suitable for power supplies with different working voltages, and the application range of the power amplifier protection device is widened.
FIG. 3 is a first schematic block diagram of a voltage output adjustable circuit 4 according to one embodiment, as shown in FIG. 3, including an adjustable resistor RH1 and a third resistor R3; wherein: one fixed terminal of the adjustable resistor RH1 is electrically connected to the input terminal 2, and the other fixed terminal of the adjustable resistor RH1 is electrically connected to one end of the third resistor R3; the other end of the third resistor R3 is directly grounded; the sliding end voltage of the adjustable resistor RH1 is used as an output voltage VoutAnd the output end of the output adjustable circuit 4 is electrically connected with the input end of the voltage clamping circuit 1.
In the specific implementation process, the power supply is electrically connected with the input wiring terminal 2, and the input voltage can be controlled by the adjustable resistor RH1 sliding end, so that the power amplifier protection device is suitable for power supplies with different working voltages, and the application range of the power amplifier protection device is widened. The implementation mode is suitable for the condition that the working voltage of the power supply cannot be flexibly changed.
FIG. 4 is a second schematic block diagram of the voltage output tunable circuit 4 in one embodiment, and as shown in FIG. 4, the voltage output tunable circuit 4 includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and an operational amplifier U2; wherein: the inverting input end of the operational amplifier U2 is electrically connected with the anode of the input connecting terminal 2 through a fourth resistor R4, and the non-inverting input end of the operational amplifier U2 is electrically connected with the cathode of the input connecting terminal 2 through a fifth resistor R5; the inverting input terminal of the operational amplifier U2 is connected to the output terminal thereof through a sixth resistor R6, the non-inverting input terminal thereof is grounded through a seventh resistor R7, and the output terminal of the operational amplifier U2 is electrically connected to the input terminal of the voltage clamp circuit 1.
In the implementation process, when the positive and negative voltages input from the input terminal 2 of the operational amplifier U2 are V+And V_At an output voltage of VoThe calculation relationship is specifically as follows:
the control of the input voltage can be realized by adjusting the input voltage of the operational amplifier U2, the embodiment is suitable for the test occasion of the adjustable power supply, and the performance test of the power amplifier is carried out by immediately changing the input of the voltage.
In a specific implementation process, the voltage output adjustable circuit 4 may be built by a discrete device, or may also be configured to control the output by using an integrated chip, such as an internal auxiliary DAC of the AD936x series, which may be determined according to an actual application situation.
The power amplifier protection device can further comprise a power amplifier bias connecting circuit 5, wherein the input end of the power amplifier bias connecting circuit 5 is electrically connected with the output end of the voltage clamping circuit 1, and the output end of the power amplifier bias connecting circuit 5 is electrically connected with the output wiring terminal 3 and is electrically connected with a bias part of the power amplifier.
Fig. 5 is a schematic structural diagram of the power amplifier bias connection circuit 5 in an embodiment, and as shown in fig. 5, a second capacitor C2 and a third capacitor C3 which are directly grounded are arranged between the input end and the output end of the power amplifier bias connection circuit 5, and are used for decoupling filtering of the circuit and inputting a clamped voltage to the bias part of the power amplifier PA.
In the specific implementation process, a power amplifier protection device integrates a voltage output adjustable circuit 4, a voltage clamping circuit 1 and a power amplifier bias connecting circuit 5, the voltage clamping circuit is effectively arranged for a power amplifier with a certain specific specification, the bias voltage of the power amplifier is limited within a certain range, the power amplifier is protected, the operation is convenient, the occupied space is small, and the power amplifier protection device can be well used for large-batch production.
It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not limitations to the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (8)
1. A voltage clamp circuit, characterized by: the circuit comprises a voltage stabilization control module, a first resistor, a second resistor and a first capacitor; wherein:
one end of the first resistor is used as the input end of the voltage clamping circuit and is used for inputting external voltage into the voltage clamping circuit, and the other end of the first resistor is electrically connected with one end of the first capacitor, one end of the second resistor and the first port of the voltage stabilization control module;
the other end of the first capacitor and the other end of the second resistor are grounded;
and the second port of the voltage stabilization control module is grounded, and the third port of the voltage stabilization control module is used as the output end of the voltage clamping circuit and used for outputting voltage.
2. The voltage clamping circuit of claim 1, wherein: the voltage stabilization control module adopts TL431 series voltage stabilization chips.
3. A kind of power amplifier protective device, characterized by that: comprising the voltage clamp circuit of claim 2, an input terminal and an output terminal; wherein:
the input end of the voltage clamping circuit inputs external voltage through the input wiring terminal;
and the output end of the voltage clamping circuit inputs voltage into the power amplifier through the output wiring terminal.
4. The power amplifier protection device of claim 3, wherein: the voltage output adjustable circuit is also included; the input end of the voltage output adjustable circuit is electrically connected with the input wiring terminal; the output end of the voltage output adjustable circuit is electrically connected with the input end of the voltage clamping circuit and is used for adjusting the input voltage of the voltage clamping circuit.
5. The power amplifier protection device of claim 4, wherein: the voltage output adjustable circuit comprises an adjustable resistor and a third resistor; wherein:
one fixed terminal of the adjustable resistor is electrically connected with the input connecting terminal, and the other fixed terminal of the adjustable resistor is electrically connected with one end of the third resistor;
the other end of the third resistor is directly grounded;
the sliding end of the adjustable resistor is used as the output end of the voltage output adjustable circuit and is electrically connected with the input end of the voltage clamping circuit.
6. The power amplifier protection device of claim 4, wherein: the voltage output adjustable circuit comprises a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor and an operational amplifier; wherein:
the inverting input end of the operational amplifier is electrically connected with the anode of the input wiring terminal through a fourth resistor, and the non-inverting input end of the operational amplifier is electrically connected with the cathode of the input wiring terminal through a fifth resistor;
the inverting input end of the operational amplifier is connected with the output end of the operational amplifier through a sixth resistor, the non-inverting input end of the operational amplifier is grounded through a seventh resistor, and the output end of the operational amplifier is electrically connected with the input end of the voltage clamping circuit.
7. The power amplifier protection device of claim 4, 5 or 6, wherein: the power amplifier is characterized by further comprising a power amplifier bias connecting circuit, wherein the input end of the power amplifier bias connecting circuit is electrically connected with the output end of the voltage clamping circuit, and the output end of the power amplifier bias connecting circuit is electrically connected with the output wiring terminal and is used for being electrically connected with a bias part of the power amplifier.
8. The power amplifier protection device of claim 7, wherein: and a second capacitor and a third capacitor which are directly grounded are arranged between the input end and the output end of the power amplifier bias connection circuit and are used for decoupling and filtering of the circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922250824.5U CN211296179U (en) | 2019-12-13 | 2019-12-13 | Voltage clamping circuit and power amplifier protection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922250824.5U CN211296179U (en) | 2019-12-13 | 2019-12-13 | Voltage clamping circuit and power amplifier protection device |
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| Publication Number | Publication Date |
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| CN211296179U true CN211296179U (en) | 2020-08-18 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201922250824.5U Expired - Fee Related CN211296179U (en) | 2019-12-13 | 2019-12-13 | Voltage clamping circuit and power amplifier protection device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112146776A (en) * | 2020-09-30 | 2020-12-29 | 中车大连电力牵引研发中心有限公司 | Energy-saving high accuracy temperature detects integrated circuit board |
-
2019
- 2019-12-13 CN CN201922250824.5U patent/CN211296179U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112146776A (en) * | 2020-09-30 | 2020-12-29 | 中车大连电力牵引研发中心有限公司 | Energy-saving high accuracy temperature detects integrated circuit board |
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Address after: 510730 No.10, Shenzhou Road, Guangzhou Science City, economic and Technological Development Zone, Huangpu District, Guangzhou City, Guangdong Province Patentee after: Jingxin Network System Co.,Ltd. Address before: 510730 No.10, Shenzhou Road, Guangzhou Science City, economic and Technological Development Zone, Huangpu District, Guangzhou City, Guangdong Province Patentee before: COMBA TELECOM SYSTEMS (CHINA) Ltd. |
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| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20200818 |