CN208209518U - Surge restraint circuit in parallel - Google Patents
Surge restraint circuit in parallel Download PDFInfo
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- CN208209518U CN208209518U CN201820513677.9U CN201820513677U CN208209518U CN 208209518 U CN208209518 U CN 208209518U CN 201820513677 U CN201820513677 U CN 201820513677U CN 208209518 U CN208209518 U CN 208209518U
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Abstract
A kind of surge restraint circuit in parallel provided by the utility model, including controller, first switch tube and second switch, the control terminal of first switch tube and second switch is electrically connected with the controller, with on or off under the control of the controller, the conduction impedance of second switch is less than first switch tube, the single avalanche energy of first switch tube is higher than second switch, and when the voltage of input signal is in the first preset range, controller control first switch tube and second switch are both turned on；When the voltage of input signal is in the second preset range; controller controls first switch tube conducting, second switch shutdown; pass through setting two switching tubes in parallel; it is selected to use different switching tubes according to electrical signal intensity size; the intensity for limiting output signal, is effectively protected late-class circuit, while can reduce the conducting transmission loss of the energy under normal operating conditions; be conducive to power MOS pipe type selecting, realize High-current output surge module.
Description
Technical field
The utility model relates to direct current surge suppressor technical fields, in particular to a kind of Surge suppression electricity in parallel
Road.
Background technique
Surge Suppressors (surge suppressor), is also Surge Protector, lightning protection device, is a kind of for various electricity
Sub- equipment, instrument and meter, communication line provide the electronic device of security protection.When in electric loop or communication line because outer
When the interference on boundary generates peak current or voltage suddenly, shunting can be connected in Surge Protector in a very short period of time, to keep away
Exempt from damage of the surge to other equipment in circuit.
The inside metal-oxide-semiconductor of direct current surge suppressor requires to have higher single avalanche energy (EAS single avalanche energy), but
Its conduction impedance (Rds) is lost greatly, under normal working voltage big；It is not easy to manufacture high current surge suppressor.Therefore it is badly in need of design
It is a kind of that small high current surge restraint circuit is lost.
Utility model content
The purpose of this utility model is to provide a kind of surge restraint circuits in parallel, are reduced inside surge suppressor with realizing
The purpose of the conduction loss of metal-oxide-semiconductor.
The utility model is realized in this way:
A kind of parallel connection surge restraint circuit, the surge restraint circuit includes controller, first switch tube and second switch
Pipe, the first switch tube and the second switch are in parallel, the control terminal of the first switch tube and the second switch
It is electrically connected with the controller, with the on or off under the control of the controller, the conducting of the second switch hinders
The anti-impedance less than first switch tube, the single that the single avalanche energy of the first switch tube is higher than the second switch are avenged
Energy is collapsed, when the voltage of input signal is in the first preset range, the controller controls the first switch tube and described
Second switch is both turned on；When the voltage of input signal is in the second preset range, the controller control described first is opened
Close pipe conducting, second switch shutdown.
Further, the surge restraint circuit in parallel includes signal output end and output signal sample circuit, and described the
One switching tube and the output end of the second switch are electrically connected with the signal output end, the output signal sample circuit
It is electrically connected with the signal output end, the output signal sample circuit is also electrically connected with the controller, the output signal
Sample circuit is used to detect the voltage of the output signal of surge restraint circuit in parallel, and the voltage for the output signal that will test is sent
To controller, the controller controls the working condition of first switch tube according to the voltage of output signal.
Further, the surge restraint circuit in parallel includes signal input part and input signal sample circuit, the letter
Number input terminal is all connected with the input terminal of the first switch tube, the input terminal of second switch, the input signal sampling electricity
Road is electrically connected with the signal input part, and the input signal sample circuit is also electrically connected with the controller, the input letter
Number sample circuit is used to detect the voltage of the input signal of surge restraint circuit in parallel, the voltage hair for the input signal that will test
It send to controller, the controller controls conducting or the pass of first switch tube and second switch according to the voltage of input signal
It is disconnected.
Further, the grid of the first switch tube is electrically connected with the controller, the drain electrode of the first switch tube
It is electrically connected with the signal input part, the source electrode of the first switch tube is electrically connected with the signal output end.
Further, the grid of the second switch is electrically connected with the controller, the drain electrode of the second switch
It is electrically connected with the signal input part, the source electrode of the second switch is electrically connected with the signal output end.
Further, first preset range is 8~36V.
Further, second preset range is 36~80V.
Further, when the input signal is greater than the second preset range, controller control first switch tube and
Second switch is turned off.
Further, the output signal sample circuit includes first resistor and second resistance, and the of the first resistor
One end is electrically connected with the signal output end, and the second end of the first resistor and the first port I/O of the controller are electrically connected
It connects, the first end of the second resistance is electrically connected with the second end of the first resistor, the second end ground connection of the second resistance.
Further, the input signal sample circuit includes 3rd resistor and the 4th resistance, and the of the 3rd resistor
One end is electrically connected with the signal input part, and the second end of the 3rd resistor and the 2nd port I/O of the controller are electrically connected
It connects, the first end of the 4th resistance is electrically connected with the second end of the 3rd resistor, the second end ground connection of the 4th resistance.
Compared with the prior art, the utility model has the following beneficial effects:
A kind of surge restraint circuit in parallel provided by the utility model, including controller, first switch tube and second switch
Pipe, the first switch tube and the second switch are in parallel, the control terminal of the first switch tube and the second switch
It is electrically connected with the controller, with the on or off under the control of the controller, the conducting of the second switch hinders
The anti-impedance less than first switch tube, the single that the single avalanche energy of the first switch tube is higher than the second switch are avenged
Energy is collapsed, when the voltage of input signal is in the first preset range, the controller controls the first switch tube and described
Second switch is both turned on；When the voltage of input signal is in the second preset range, the controller control described first is opened
Pipe conducting, second switch shutdown are closed, by setting two switching tubes in parallel, according to the selection of electrical signal intensity size using not
Same switching tube, limits the intensity of output signal, is effectively protected late-class circuit, while can reduce under normal operating conditions
Transmission loss is connected in energy, is conducive to power MOS pipe type selecting, realizes High-current output surge module.
To enable the above objects, features, and advantages of the utility model to be clearer and more comprehensible, preferred embodiment is cited below particularly, and
Cooperate appended attached drawing, is described in detail below.
Detailed description of the invention
It, below will be to required in embodiment in order to illustrate more clearly of the technical solution of the utility model embodiment
The attached drawing used is briefly described, it should be understood that the following drawings illustrates only some embodiments of the utility model, therefore not
It should be considered as the restriction to range, for those of ordinary skill in the art, without creative efforts,
It can also be obtained according to these attached drawings other relevant attached drawings.
Fig. 1 shows a kind of schematic block diagram of surge restraint circuit in parallel provided by the utility model.
Fig. 2 shows the circuit connection diagrams of surge restraint circuit in parallel.
Icon: 100- parallel connection surge restraint circuit；110- controller 111；MA- first switch tube；MB- second switch；
P1- signal input part；P2- signal output end；151- input signal sample circuit；R3- 3rd resistor；The 4th resistance of R4-；153-
Output signal sample circuit；R1- first resistor；R2- second resistance.
Specific embodiment
Below in conjunction with attached drawing in the utility model embodiment, the technical scheme in the embodiment of the utility model is carried out clear
Chu is fully described by, it is clear that the described embodiments are only a part of the embodiments of the utility model, rather than whole realities
Apply example.The component of the utility model embodiment being usually described and illustrated herein in the accompanying drawings can be come with a variety of different configurations
Arrangement and design.Therefore, the detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit below
The range of claimed invention, but it is merely representative of the selected embodiment of the utility model.Based on the utility model
Embodiment, those skilled in the art's every other embodiment obtained without making creative work, all
Belong to the range of the utility model protection.
It should also be noted that similar label and letter indicate similar terms in following attached drawing, therefore, once a certain Xiang Yi
It is defined in a attached drawing, does not then need that it is further defined and explained in subsequent attached drawing.
In the description of the present invention, it should be noted that term " on ", "lower", "left", "right", "inner", "outside" etc.
The orientation or positional relationship of instruction be based on the orientation or positional relationship shown in the drawings or the utility model product use when
The orientation or positional relationship usually put, is merely for convenience of describing the present invention and simplifying the description, rather than instruction or dark
Show that signified device or element must have a particular orientation, be constructed and operated in a specific orientation, therefore should not be understood as pair
The limitation of the utility model.
In the description of the present invention, it should also be noted that, unless otherwise clearly defined and limited, term " is set
Set ", " installation ", " connected ", " connection " shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection,
Or it is integrally connected；It can be mechanical connection, be also possible to be electrically connected；It can be directly connected, intermediary can also be passed through
It is indirectly connected, can be the connection inside two elements.
It is in the description of the present invention, it should also be noted that, herein, such as first and second or the like pass
It is that term is only used to distinguish one entity or operation from another entity or operation, and not necessarily requires or secretly
Show that there are any actual relationship or orders between these entities or operation.Term "horizontal", "vertical", " pendency " etc.
Term is not offered as requiring component abswolute level or pendency, but can be slightly tilted.As "horizontal" only refers to its direction phase
It is more horizontal for "vertical", it is not to indicate that the structure is had to fully horizontally, but can be slightly tilted.Term " packet
Include ", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion so that including the mistake of a series of elements
Journey, method, article or equipment not only include those elements, but also including other elements that are not explicitly listed, either
It further include for elements inherent to such a process, method, article, or device.In the absence of more restrictions, by sentence
The element that "including a ..." limits, it is not excluded that also deposit in the process, method, article or apparatus that includes the element
In other identical element.For the ordinary skill in the art, above-mentioned term can be understood in this reality with concrete condition
With the concrete meaning in novel.
With reference to the accompanying drawing, it elaborates to some embodiments of the utility model.In the absence of conflict, under
The feature in embodiment and embodiment stated can be combined with each other.
Embodiment
Present embodiments provide a kind of surge restraint circuit 100 in parallel, referring to Fig. 1, Fig. 1 show the present embodiment provides
Surge restraint circuit in parallel 100 schematic diagram.
Surge restraint circuit 100 in parallel includes controller, first switch tube MA and second switch MB, first switch tube MA
It is electrically connected with the controller with the control terminal of second switch MB, on or off under the control of the controller, by signal
It carries out being processed and transmitted to late-class circuit.
Surge restraint circuit 100 in parallel further includes input signal sample circuit 151 and output signal sample circuit 153, defeated
Enter signal sample circuit 151 for sampled input signal, the input signal of sampling is transmitted to controller；Output signal sampling electricity
Road 153 is used for sampled output signal, and the output signal of sampling is transmitted to controller, controller according to sampling input signal and
The working condition of output signal control the first switch tube MA and second switch MB of sampling.
For example, referring to Fig. 2, in this present embodiment, first switch tube MA and second switch MB are in parallel, and surge in parallel presses down
Circuit 100 processed further includes signal input part P1 and signal output end P2, the input terminal of signal input part P1 and first switch tube MA,
The input terminal of second switch MB is all connected with, and signal output end P2 and the output end of first switch tube MA and second switch MB are equal
Connection, signal input part P1 import first switch tube MA or second switch MB for accessing input signal, by input signal,
First switch tube MA or second switch MB, which conducts after handling input signal to signal output end P2, to be exported.
It should be noted that in this present embodiment, the parallel connection surge restraint circuit 100 further includes protection circuit, described
Circuit and signal input part P1 is protected to be electrically connected, the protection circuit prevents the signal that voltage is excessive for filtering out high current
Or signal corruption first switch tube MA and/or second switch MB that electric current is excessive.
In this present embodiment, first switch tube MA and second switch MB can be metal-oxide-semiconductor, but not limited to this.First opens
The grid for closing pipe MA is electrically connected with the controller, and the drain electrode of first switch tube MA is electrically connected with signal input part P1, first switch tube
The source electrode of MA is electrically connected with signal output end P2.The grid of second switch MB is electrically connected with the controller, second switch MB's
Drain electrode is electrically connected with signal input part P1, and the source electrode of second switch MB is electrically connected with signal output end P2.In this present embodiment,
The grid and the grid of second switch MB and the control terminal of controller of first switch tube MA is electrically connected, for the control in controller
Make lower on or off.
The input signal sample circuit 151 is sent for sampling to input signal, and by the input signal of sampling
To controller, the output signal sample circuit 153 is sent for sampling to output signal, and by the output signal of sampling
To controller, the controller is opened according to the input signal of sampling and the output signal control first switch tube MA or second of sampling
Close pipe MB on or off.
Input signal sample circuit 151 is electrically connected with signal input part P1, and input signal sample circuit 151 is gone back and controller
Electrical connection, input signal sample circuit 151 are used to detect the input signal of surge restraint circuit 100 in parallel, for example, detection input
The voltage of signal, the voltage for the input signal that will test are sent to controller, and controller is controlled according to the voltage of input signal
The on or off of first switch tube MA and second switch MB.
In this present embodiment, input signal sample circuit 151 includes 3rd resistor R3 and the 4th resistance R4,3rd resistor R3
First end be electrically connected with signal input part P1, the second end of 3rd resistor R3 is electrically connected with the 2nd port I/O of controller,
The first end of four resistance R4 is electrically connected with the second end of 3rd resistor R3, the second end ground connection of the 4th resistance R4.
The output end of first switch tube MA and second switch MB are electrically connected with signal output end P2, output signal sampling
Circuit 153 is electrically connected with signal output end P2, and output signal sample circuit 153 is for detecting surge restraint circuit 100 in parallel
The voltage of output signal, and the voltage for the output signal that will test is sent to controller, controller is according to the electricity of output signal
The working condition of voltage-controlled first switch tube MA processed.
In this present embodiment, output signal sample circuit 153 includes first resistor R1 and second resistance R2, first resistor R1
First end be electrically connected with signal output end P2, the second end of first resistor R1 is electrically connected with the first port I/O of controller,
The first end of two resistance R2 is electrically connected with the second end of first resistor R1, the second end ground connection of second resistance R2.
It should be noted that the input signal sample circuit 151 and output signal sample circuit 153 turn including digital-to-analogue
The Subcircuits modules such as circuit are changed, convert digital data transmission to controller for the analog signal of sampling.In this present embodiment,
The controller can be the processing chips with same or similar function such as DSP control chip, single-chip microcontroller, fpga chip.
In this present embodiment, first switch tube MA is the function of high EAS (single avalanche energy), low Rdson (conduction impedance)
Rate device, the second switch MB are the power device of low EAS, low Rdson.The Rdson of second switch MB is less than first
The EAS of the Rdson of switching tube MA, first switch tube MA are higher than the EAS of second switch MB, when the voltage of input signal is in the
When one preset range, for example, first preset range is that can be 8~36V.Controller controls first switch tube MA and second
Switching tube MB is both turned on；At this point, since the conduction impedance of second switch MB is small, so electric current is upper from second switch MB
It crosses, so that energy loss when normally is small.
When there is overvoltage condition in the voltage of input signal, i.e., when the voltage of input signal is in the second preset range, control
Device controls first switch tube MA conducting, second switch MB shutdown.In this present embodiment, second preset range can be 36
~80V.First switch tube MA conducting, second switch MB shutdown, then electric signal is by first switch tube MA through signal output end
P2 is transmitted to late-class circuit.First switch tube MA is the power device of high EAS (single avalanche energy), low Rdson (conduction impedance)
Part, electric signal is by that can limit the energy of signal.Controller is opened according to the output signal of sampling control first
The working condition of pipe MA is closed, for example, output signal of the controller according to sampling, controls the driving voltage of first switch tube MA, make
First switch tube MA works in linear condition, so that output signal is limited in the value of setting, the electricity consumption of effective protection late-class circuit is set
It is standby.
When the voltage of the input signal of the received sampling of controller tends to normally, that is, is in the first preset range, control
Device controls second switch MB opening herein, and electric signal recovery is transmitted by second switch MB.
When input signal is greater than the second preset range, controller control first switch tube MA and second switch MB is closed
It is disconnected, to prevent protection late-class circuit.
In conclusion the utility model provides a kind of surge restraint circuit 100 in parallel, including controller, first switch
Pipe MA and second switch MB, the first switch tube MA and the second switch MB is in parallel, the first switch tube MA and
The control terminal of the second switch MB is electrically connected with the controller, to be connected or close under the control of the controller
Disconnected, the conduction impedance of the second switch MB is less than the impedance of first switch tube MA, the single snow of the first switch tube MA
The single avalanche energy that energy is higher than the second switch MB is collapsed, when the voltage of input signal is in the first preset range,
The controller controls the first switch tube MA and second switch MB and is both turned on；When the voltage of input signal is in the
When two preset ranges, the controller controls the first switch tube MA conducting, second switch MB shutdown, in parallel by setting
Two switching tubes, according to electrical signal intensity size select use different switching tubes, limit the intensity of output signal, effectively
Late-class circuit is protected, while the conducting transmission loss of the energy under normal operating conditions can be reduced, is conducive to power MOS pipe choosing
Type realizes High-current output surge module.
The above descriptions are merely preferred embodiments of the present invention, is not intended to limit the utility model, for this
For the technical staff in field, various modifications and changes may be made to the present invention.It is all in the spirit and principles of the utility model
Within, any modification, equivalent replacement, improvement and so on should be included within the scope of protection of this utility model.
Claims (10)
1. a kind of parallel connection surge restraint circuit, which is characterized in that the parallel connection surge restraint circuit includes controller, first switch
Pipe and second switch, the first switch tube and the second switch are in parallel, and the first switch tube and described second is opened
The control terminal for closing pipe is electrically connected with the controller, and with the on or off under the control of the controller, described second is opened
The conduction impedance for closing pipe is less than the impedance of first switch tube, and the single avalanche energy of the first switch tube is higher than described second and opens
The single avalanche energy for closing pipe, when the voltage of input signal is in the first preset range, the controller control described first
Switching tube and the second switch are both turned on；When the voltage of input signal is in the second preset range, the controller control
Make the first switch tube conducting, second switch shutdown.
2. parallel connection surge restraint circuit as described in claim 1, which is characterized in that the parallel connection surge restraint circuit includes letter
The output end of number output end and output signal sample circuit, the first switch tube and the second switch with the signal
Output end electrical connection, the output signal sample circuit are electrically connected with the signal output end, the output signal sample circuit
It is also electrically connected with the controller, the output signal sample circuit is used to detect the output signal of surge restraint circuit in parallel
Voltage, the voltage for the output signal that will test are sent to controller, and the controller is according to the voltage of output signal control the
The working condition of one switching tube.
3. parallel connection surge restraint circuit as claimed in claim 2, which is characterized in that the parallel connection surge restraint circuit includes letter
The input terminal of number input terminal and input signal sample circuit, the signal input part and the first switch tube, second switch
Input terminal be all connected with, the input signal sample circuit is electrically connected with the signal input part, input signal sampling electricity
Road is also electrically connected with the controller, and the input signal sample circuit is used to detect the input signal of surge restraint circuit in parallel
Voltage, the voltage for the input signal that will test is sent to controller, and the controller is controlled according to the voltage of input signal
The on or off of first switch tube and second switch.
4. parallel connection surge restraint circuit as claimed in claim 3, which is characterized in that the grid of the first switch tube with it is described
Controller electrical connection, the drain electrode of the first switch tube are electrically connected with the signal input part, the source electrode of the first switch tube
It is electrically connected with the signal output end.
5. parallel connection surge restraint circuit as claimed in claim 4, which is characterized in that the grid of the second switch with it is described
Controller electrical connection, the drain electrode of the second switch are electrically connected with the signal input part, the source electrode of the second switch
It is electrically connected with the signal output end.
6. parallel connection surge restraint circuit as described in claim 1, which is characterized in that first preset range is 8~36V.
7. parallel connection surge restraint circuit as described in claim 1, which is characterized in that second preset range is 36~80V.
8. parallel connection surge restraint circuit as described in claim 1, which is characterized in that preset when the input signal is greater than second
When range, the controller control first switch tube and second switch are turned off.
9. parallel connection surge restraint circuit as claimed in claim 2, which is characterized in that the output signal sample circuit includes the
One resistance and second resistance, the first end of the first resistor are electrically connected with the signal output end, and the of the first resistor
Two ends are electrically connected with the first port I/O of the controller, and the second of the first end of the second resistance and the first resistor
End electrical connection, the second end ground connection of the second resistance.
10. parallel connection surge restraint circuit as claimed in claim 4, which is characterized in that the input signal sample circuit includes
3rd resistor and the 4th resistance, the first end of the 3rd resistor are electrically connected with the signal input part, the 3rd resistor
Second end is electrically connected with the 2nd port I/O of the controller, and the of the first end of the 4th resistance and the 3rd resistor
The electrical connection of two ends, the second end ground connection of the 4th resistance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820513677.9U CN208209518U (en) | 2018-04-11 | 2018-04-11 | Surge restraint circuit in parallel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820513677.9U CN208209518U (en) | 2018-04-11 | 2018-04-11 | Surge restraint circuit in parallel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208209518U true CN208209518U (en) | 2018-12-07 |
Family
ID=64523861
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201820513677.9U Active CN208209518U (en) | 2018-04-11 | 2018-04-11 | Surge restraint circuit in parallel |
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| Country | Link |
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| CN (1) | CN208209518U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108336722A (en) * | 2018-04-11 | 2018-07-27 | 四川升华电源科技有限公司 | Surge restraint circuit in parallel |
-
2018
- 2018-04-11 CN CN201820513677.9U patent/CN208209518U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108336722A (en) * | 2018-04-11 | 2018-07-27 | 四川升华电源科技有限公司 | Surge restraint circuit in parallel |
| CN108336722B (en) * | 2018-04-11 | 2024-01-16 | 四川升华电源科技有限公司 | Parallel surge suppression circuit |
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