CN205160047U - Overvoltage crowbar and device - Google Patents
Overvoltage crowbar and device Download PDFInfo
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- CN205160047U CN205160047U CN201520956854.7U CN201520956854U CN205160047U CN 205160047 U CN205160047 U CN 205160047U CN 201520956854 U CN201520956854 U CN 201520956854U CN 205160047 U CN205160047 U CN 205160047U
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Abstract
The utility model provides a pair of overvoltage crowbar and device, overvoltage crowbar electric connection is between input circuit and switching power supply circuit. Overvoltage crowbar includes that voltage input end, the 2nd voltage input end, voltage output end, input voltage listen the circuit, reference voltage provides circuit and switch tube. Voltage input end provides circuit electric connection with reference voltage for receive reference voltage. Circuit electric connection is listened with input voltage to the 2nd voltage input end for the comparative voltage is treated in the receipt. The voltage output end is connected with the under -voltage shutoff pin of switching power supply circuit's power control chip's input through the switch tube. When the comparative voltage excessive pressure was treated in the input, overvoltage crowbar's voltage output end out put voltage control signal made the switching power supply circuit stop work. The utility model provides an overvoltage protector. The technical problem that no overvoltage protection probably damaged switching power supply circuit has effectively been solved among the current switching power supply circuit.
Description
Technical field
The utility model relates to circuit protection technical field, in particular to a kind of overvoltage crowbar and device.
Background technology
Alternating current being converted to direct current is power consumption equipment when powering, and generally needs to provide the constant voltage Switching Power Supply of a DC-DC to export to power consumption equipment to provide stable constant voltage DC.In prior art, a conventional power supply control chip realizes a flyback constant voltage DC output switch power source.
But realize at power supply control chip, in the circuit of a flyback constant voltage DC output switch power source, not inputting the function of overvoltage protection, when input voltage is too high, Switching Power Supply may be caused to damage.How providing a kind of protective circuit that can control Switching Power Supply when input voltage is too high and automatically shut down, is the anxious technical issues that need to address for a person skilled in the art.
Utility model content
In view of this, the utility model provides a kind of overvoltage crowbar, to improve the technical problem that Switching Power Supply may be caused to damage when input voltage is too high in prior art.
For achieving the above object, the utility model provides following technical scheme:
A kind of overvoltage crowbar, described overvoltage crowbar is electrically connected between input circuit and switching power circuit.Overvoltage crowbar described in overvoltage crowbar comprises the first voltage input end, the second voltage input end, voltage output end, input voltage circuit for detecting, reference voltage provide circuit and switching tube.Described reference voltage provides circuit for providing a reference voltage, and described first voltage input end and described reference voltage provide circuit to be electrically connected, for receiving described reference voltage.Described input voltage circuit for detecting is used for the input voltage of described input circuit to be converted to voltage to be compared, and described second voltage input end and described input voltage circuit for detecting are electrically connected, for receiving described voltage to be compared.Described overvoltage crowbar by more described reference voltage and described voltage to be compared, and exports a voltage control signal according to comparative result from described voltage output end.Described voltage output end turns off pin by described switching tube with the input undervoltage of the power supply control chip of described switching power circuit and is connected.When inputting described electric voltage over press to be compared, the voltage output end of described overvoltage crowbar exports described voltage control signal makes described switching power circuit quit work.
Further, reference voltage described in above-mentioned overvoltage crowbar provides circuit to comprise the first voltage stabilizing didoe and the first resistance.The plus earth of described first voltage stabilizing didoe; the negative electrode of described first voltage stabilizing didoe is connected with the positive pole of described input circuit via described first resistance, and the first voltage input end of described overvoltage crowbar is connected between described voltage stabilizing didoe and described first resistance.
Further; above-mentioned overvoltage crowbar also comprises: an operational amplification circuit; the homophase input pin of described operational amplification circuit forms the first voltage input end of described overvoltage crowbar; the out-phase input pin of described operational amplification circuit forms the second voltage input end of described overvoltage crowbar, and the output pin of described operational amplification circuit forms the voltage output end of described overvoltage crowbar.
Further, described in above-mentioned overvoltage crowbar, input voltage circuit for detecting comprises: the second resistance and the 3rd resistance.One end of described second resistance is connected with the positive pole of described input circuit, and the other end of described second resistance is via described 3rd grounding through resistance, and the out-phase input pin of described operational amplification circuit is connected between described second resistance and described 3rd resistance.
Further; switching tube described in above-mentioned overvoltage crowbar is the first diode; the output pin of described operational amplification circuit connects the negative electrode with described first diode, and the anode of described first diode turns off pin with the input undervoltage of the power supply control chip of described switching power circuit and is connected.
Further, above-mentioned overvoltage crowbar also comprises one the 4th resistance, and described 4th resistance is connected between the homophase input pin of described operational amplification circuit and the out-phase input pin of described operational amplification circuit.
Meanwhile, the utility model also provides a kind of over-pressure safety device, comprising: overvoltage crowbar, input circuit and switching power circuit, and described overvoltage crowbar is electrically connected between input circuit and switching power circuit.Described overvoltage crowbar comprises the first voltage input end, the second voltage input end, voltage output end, input voltage circuit for detecting, reference voltage provide circuit and switching tube.Described reference voltage provides circuit for providing a reference voltage, and described first voltage input end and described reference voltage provide circuit to be electrically connected, for receiving described reference voltage.Described input voltage circuit for detecting is used for the input voltage of described input circuit to be converted to voltage to be compared, and described second voltage input end and described input voltage circuit for detecting are electrically connected, for receiving described voltage to be compared.Described overvoltage crowbar by more described reference voltage and described voltage to be compared, and exports a voltage control signal according to comparative result from described voltage output end.Described voltage output end turns off pin by described switching tube with the input undervoltage of the power supply control chip of described switching power circuit and is connected.When inputting described electric voltage over press to be compared, the voltage output end of described overvoltage crowbar exports described voltage control signal makes described switching power circuit quit work.
Hinge structure, a kind of overvoltage crowbar that the utility model provides, described overvoltage crowbar is electrically connected between input circuit and switching power circuit.Described overvoltage crowbar comprises the first voltage input end, the second voltage input end, voltage output end, input voltage circuit for detecting, reference voltage provide circuit and switching tube.Described reference voltage provides circuit for providing a reference voltage, and described first voltage input end and described reference voltage provide circuit to be electrically connected, for receiving described reference voltage.Described input voltage circuit for detecting is used for the input voltage of described input circuit to be converted to voltage to be compared, and described second voltage input end and described input voltage circuit for detecting are electrically connected, for receiving described voltage to be compared.Described overvoltage crowbar by more described reference voltage and described voltage to be compared, and exports a voltage control signal according to comparative result from described voltage output end.Described voltage output end turns off pin by described switching tube with the input undervoltage of the power supply control chip of described switching power circuit and is connected.When inputting described electric voltage over press to be compared, the voltage output end of described overvoltage crowbar exports described voltage control signal makes described switching power circuit quit work.
Above-mentioned overvoltage crowbar can, when input voltage overvoltage, produces voltage control signal control switch power circuit and close, thus protective circuit be from damage at the output of described overvoltage crowbar.Efficiently solve the technical problem may damaging switching power circuit in existing switching power circuit without overvoltage protection.
Accompanying drawing explanation
In order to clearer explanation the utility model embodiment or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only embodiments more of the present utility model, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
Fig. 1 is the schematic diagram of the overvoltage crowbar that the utility model specific embodiment provides.
Fig. 2 is a kind of physical circuit figure of the overvoltage crowbar that the utility model specific embodiment provides.
Embodiment
Also by reference to the accompanying drawings the utility model is described in further detail below by specific embodiment.
With reference to Fig. 1, the overvoltage crowbar 200 that the utility model provides, described overvoltage crowbar 200 is electrically connected between input circuit 100 and switching power circuit 300.Described overvoltage crowbar 200, input circuit 100 form over-pressure safety device jointly with switching power circuit 300.
With reference to Fig. 1, described overvoltage crowbar 200 can comprise the first voltage input end, the second voltage input end, voltage output end, input voltage circuit for detecting 220, reference voltage provide circuit 210 and switching tube 230.
Described reference voltage provides circuit 210 for providing a reference voltage, and described first voltage input end and described reference voltage provide circuit 210 to be electrically connected, for receiving described reference voltage.Described input voltage circuit for detecting 220 is for being converted to voltage to be compared by the input voltage of described input circuit 100, and described second voltage input end and described input voltage circuit for detecting 220 are electrically connected, for receiving described voltage to be compared.Described overvoltage crowbar 200 by more described reference voltage and described voltage to be compared, and exports a voltage control signal according to comparative result from described voltage output end.Described voltage output end turns off pin by described switching tube 230 with the input undervoltage of the power supply control chip 310 of described switching power circuit 300 and is connected.
When inputting described electric voltage over press to be compared, the voltage output end of described overvoltage crowbar 220 exports described voltage control signal makes described switching power circuit 300 quit work.
Please also refer to Fig. 2; overvoltage crowbar 200 can comprise one or eight pin operational amplification circuit U3; wherein; the homophase input pin AP of operational amplification circuit U3 forms the first voltage input end of overvoltage crowbar 200; the out-phase input pin AN of operational amplification circuit U3 forms the second voltage input end of overvoltage crowbar 200, and the output pin AO of operational amplification circuit U3 forms the voltage output end of overvoltage crowbar 200.By contrasting the input voltage of homophase input pin AP and out-phase input pin AN, be used for the operating state of control switch power circuit 300 from output pin AO output voltage control signal.
Be understandable that, in other execution mode of the present utility model, operational amplification circuit U3 also can adopt comparator to realize.
The homophase input pin AP that reference voltage provides circuit 210 and computing to discharge road U3 is connected, and in specific embodiment of the utility model, reference voltage provides circuit 210 can comprise the first voltage stabilizing didoe Z1 and the first resistance R1.The plus earth of the first voltage stabilizing didoe Z1, the negative electrode of the first voltage stabilizing didoe Z1 is connected with the positive pole of input circuit via the first resistance R1, the positive pole of input circuit is connected with the operating voltage input pin VCC of operational amplification circuit, for powering for computing electric discharge road U3, operational amplification circuit operating voltage input pin VCC with can also be connected one first electric capacity C1 between ground, the first electric capacity C1 be used for filtering.The homophase input pin AP of operational amplification circuit U3 is connected between the first voltage stabilizing didoe Z1 and the first resistance R1, and the first voltage stabilizing didoe Z1 provides reference voltage to the homophase input pin AP of operational amplification circuit U3.
Be understandable that, in other execution mode of the present utility model, the first voltage-stabiliser tube Z1 also can adopt other voltage stabilizing element or voltage stabilizing circuit to realize.
Input voltage circuit for detecting 220 for obtaining voltage to be compared from input circuit 100, and particularly, input voltage circuit for detecting 220 obtains voltage to be compared from the positive pole of input circuit 100.In this specific embodiment, input voltage circuit for detecting 220 can comprise the second resistance R2 and the 3rd resistance R3.One end of second resistance R2 is connected with the positive pole of input circuit 100, and the other end of the second resistance R2 is by the 3rd resistance R3 ground connection.The out-phase input pin AN of operational amplification circuit U3 is connected between the second resistance R2 and the 3rd resistance R3, supposes that input voltage is V1, and the voltage to be compared that the out-phase input pin AN of operational amplification circuit U3 obtains is V1*R3/ (R2+R3).The magnitude of voltage to be compared that the out-phase input pin AN of operational amplification circuit U3 obtains can be adjusted by the resistance value adjusting the second resistance R2 and the 3rd resistance R3.Input voltage circuit for detecting 220 can also comprise the second electric capacity C2, and the second electric capacity C2 is used for filtering, and the second electric capacity C2 positive pole is connected with the out-phase input pin AN of operational amplification circuit U3, and the negative pole of the second electric capacity C2 is connected to the ground.
Be understandable that, in other execution mode of the present utility model, two resistant series dividing potential drop modes also can adopt other element with point compression functions or circuit to substitute.
Further, between operational amplification circuit U3 homophase input pin AP and out-phase input pin AN, be connected with the 4th resistance R4, form a negative feedback hysteresis comparator.4th resistance R4 realizes lag function, can strengthen the antijamming capability to signal fluctuation.
Switching tube 230 is for ending when the input voltage not overvoltage of input circuit 100, the output pin AO voltage control signal of operational amplification circuit U3 cannot act on power switch circuit 300, switching tube 216 conducting when the input voltage overvoltage of input circuit 100, make the output pin AO voltage control signal effect power switch circuit 300 of operational amplification circuit U3, power switch circuit 300 is quit work.In this specific embodiment, particularly, switching tube 230 is the first diode D1, and the negative electrode of the first diode D1 is connected with the output pin A0 of operational amplification circuit U3, and the anode of the first diode D1 turns off pin UVLO with the input undervoltage of the power supply control chip 310 of power switch circuit 300 and is connected.When the output pin AO of operational amplification circuit U3 exports high level, the first diode D1 ends, when the output pin AO output low level of operational amplification circuit U3, and the first diode D1 conducting.The low level of the output pin AO output of operational amplification circuit U3 drags down the voltage of the input undervoltage shutoff pin UVLO of power supply control chip 310, and power supply control chip 310 is quit work.
Be understandable that, in other execution mode of the present utility model, diode also can adopt other element with one-way conduction or circuit realiration, such as triode, is connected by circuit and makes triode conducting when operational amplification circuit U3 output low level, end when exporting high level.
Show the circuit structure of switching circuit 300 with reference to Fig. 2, input voltage positive pole is connected with the voltage input pin VIN of power supply control chip by the 5th resistance R5, and power supply control chip starts and starts working.The voltage input pin VIN of power supply control chip is connected to ground via the 3rd electric capacity C3, and the 3rd electric capacity C3 plays High frequency filter effect.The feed back input pin VFB of power supply control chip detects output voltage by the 6th resistance R6 and the 7th resistance R7, wherein, 6th resistance R6 one end connects output voltage positive pole, the other end of the 6th resistance R6 is via the 7th resistance R7 ground connection, the feed back input pin VFB of power supply control chip is connected between the 6th resistance R6 and the 7th resistance R7, realizes the detection of power supply control chip to output voltage.4th electric capacity C4, the 5th electric capacity C5 and the 8th resistance R8 form loop compensation networks, and loop compensation networks is connected between the compensation pin COMP of power supply control chip and feed back input pin VFB.
One end of 9th resistance R9 is connected to the operating voltage pin VCC of power supply control chip, winding is assisted in the power supply that the other end of the 9th resistance R9 is connected to transformer T1 via the second diode D2, realize powering to the normal work of power supply control chip, the positive pole of the 6th electric capacity C6 is connected to the operating voltage pin VCC of power supply control chip, the other end is connected to ground, and the 6th electric capacity C6 plays energy storage filter action.The output pin OUT of power supply control chip via the grid of the tenth resistance R10 and N-channel MOS FET, to control the normal switch of N-channel MOS FET.When N-channel MOS FET opens, electric current flows through transformer T1 armature winding from input, and power storage is in transformer T1.After N-channel MOS FET closes, the electric energy stored in transformer T1 is by secondary winding, and the 3rd diode D3, and output the 7th electric capacity C7, electrical energy transfer in the 7th electric capacity C7.The direct voltage at the 7th electric capacity C7 two ends, is output dc voltage.
One end of 11 resistance R11 is connected to input voltage positive pole; the other end of the 11 resistance R11 is via the 12 resistance R12 ground connection, and the input undervoltage of power supply control chip turns off pin UVLO and is connected between the 11 resistance R11 and the 12 resistance R20 for realizing input undervoltage protection.As long as when the voltage of input undervoltage shutoff pin is lower than fixed voltage (such as: 1.25V), power supply control chip will quit work, and realizes input undervoltage defencive function.13 resistance R13 is used for detecting transformer T1 primary winding current; current signal is converted to voltage signal; this voltage signal is passed to the current detecting pin CS of power supply control chip by the 14 resistance R14; realize power supply control chip detection of primary winding current and when exist input over-current phenomenon avoidance time; control power supply control chip quits work; play the function of protection switch unit, wherein, the 8th electric capacity C8 plays High frequency filter effect.Power supply control chip switching frequency pin RT connects the 15 resistance R15 to ground, realizes the effect of configuration switch frequency.The soft start pin SS of power supply control chip via the 9th electric capacity C9 ground connection, to realize the function of soft start.
Switching circuit 300 can also comprise: the tenth electric capacity C10, the 11 electric capacity C11, the second voltage-stabiliser tube Z2 and the 4th diode D4.The positive pole of the tenth electric capacity C10 is connected to the positive pole of input circuit 100, the minus earth of the tenth electric capacity C10.11 electric capacity C11 connects and the input undervoltage of power supply control chip 310 turns off between pin UVLO and ground.The anode of the second voltage-stabiliser tube Z2 connects the positive pole of input circuit 100, and the drain electrode that the negative pole of the second voltage-stabiliser tube Z2 is connected to N-channel MOS FET via the 4th diode connects, and wherein, the negative pole of the second voltage-stabiliser tube Z2 is connected with the negative pole of the 4th diode.
Give one example the specific works state describing above-mentioned overvoltage crowbar below.Suppose, reference voltage provides in-phase input end that circuit 210 is operational amplification circuit U3 to provide the reference voltage of 2.5V.And need the magnitude of voltage inputting overvoltage protection to be 25V, so in order to make V1*R3/ (R2+R3)=2.5V, the resistance of wherein V1=25V, the second resistance R2 can be set to 18K Ω, and the resistance of the 3rd resistance R3 can be set to 2K Ω.
When the input cathode voltage of input circuit 100 is less than 25V (not overvoltage), after now the second resistance R2 and the 3rd resistance R3 carries out series connection dividing potential drop, dividing potential drop on the 3rd resistance R3 is less than 2.5V, namely the voltage of the homophase input pin AP of operational amplification circuit U3 is 2.5V, and the voltage of the out-phase input pin AN of operational amplification circuit U3 is less than 2.5V, now the output pin AO of operational amplification circuit U3 exports high level.The negative electrode of the first diode D1 is connected with the output pin AO of operational amplification circuit U3; now the first diode D1 ends; the voltage control signal of the output pin AO output of operational amplification circuit U3 cannot act on the input undervoltage shutoff pin UVLO of power supply control chip 310, can not affect the normal input undervoltage defencive function of power supply control chip 310.
When the input cathode voltage of input circuit 100 is greater than 25V (overvoltage), after now the second resistance R2 and the 3rd resistance R3 carries out series connection dividing potential drop, dividing potential drop on the second resistance R2 is greater than 2.5V, namely the voltage of the homophase input pin AP of operational amplification circuit U3 is 2.5V, and the voltage of the out-phase input pin AN of operational amplification circuit U3 is greater than 2.5V, the now output pin AO output low level of operational amplification circuit U3.The negative electrode of the first diode D1 is connected with the output pin AO of operational amplification circuit U3, now the first diode D1 conducting, the input undervoltage of the voltage control signal effect power supply control chip 310 of the output pin AO output of operational amplification circuit U3 turns off pin UVLO, and the voltage control signal of the output pin AO output of operation amplifier U3 can drag down the voltage of the input undervoltage shutoff pin UVLO of power supply control chip 310.Make power supply control chip 310 cannot normally realize input undervoltage defencive function, power supply control chip 310 quits work, and whole switching power circuit 300 quits work, and quits work to realize overvoltage protection by making switching power circuit 300 in time.
In sum, above-mentioned overvoltage crowbar can, when input voltage is higher, produces voltage control signal control switch power circuit and close, thus protective circuit is from damage at the output of described overvoltage crowbar.Efficiently solve the technical problem may damaging switching power circuit in existing switching power circuit without overvoltage protection.
It should be noted that, in this article, the such as relational terms of first and second grades and so on is only used for an entity or operation to separate with another entity or operating space, and not necessarily requires or imply the relation that there is any this reality between these entities or operation or sequentially.And term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thus make to comprise the article of a series of key element or equipment not only comprises those key elements, but also comprise other key elements clearly do not listed.When not more restrictions, the key element limited by statement " comprising ... ", and be not precluded within the article or equipment comprising described key element and also there is other identical element.
The foregoing is only preferred embodiment of the present utility model, be not limited to the utility model, for a person skilled in the art, the utility model can have various modifications and variations.All within spirit of the present utility model and principle, any amendment done, equivalent replacement, improvement etc., all should be included within protection range of the present utility model.It should be noted that: represent similar terms in similar label and letter accompanying drawing below, therefore, once be defined in an a certain Xiang Yi accompanying drawing, then do not need to define further it and explain in accompanying drawing subsequently.
Claims (10)
1. an overvoltage crowbar, it is characterized in that: described overvoltage crowbar is electrically connected between input circuit and switching power circuit, overvoltage crowbar described in overvoltage crowbar comprises the first voltage input end, second voltage input end, voltage output end, input voltage circuit for detecting, reference voltage provides circuit and switching tube, described reference voltage provides circuit for providing a reference voltage, described first voltage input end and described reference voltage provide circuit to be electrically connected, for receiving described reference voltage, described input voltage circuit for detecting is used for the input voltage of described input circuit to be converted to voltage to be compared, described second voltage input end and described input voltage circuit for detecting are electrically connected, for receiving described voltage to be compared, described overvoltage crowbar is by more described reference voltage and described voltage to be compared, and export a voltage control signal according to comparative result from described voltage output end, described voltage output end turns off pin by described switching tube with the input undervoltage of the power supply control chip of described switching power circuit and is connected,
When inputting described electric voltage over press to be compared, the voltage output end of described overvoltage crowbar exports described voltage control signal makes described switching power circuit quit work.
2. overvoltage crowbar as claimed in claim 1; it is characterized in that: described reference voltage provides circuit to comprise the first voltage stabilizing didoe and the first resistance; the plus earth of described first voltage stabilizing didoe; the negative electrode of described first voltage stabilizing didoe is connected with the positive pole of described input circuit via described first resistance, and the first voltage input end of described overvoltage crowbar is connected between described voltage stabilizing didoe and described first resistance.
3. overvoltage crowbar as claimed in claim 1; it is characterized in that: described overvoltage crowbar also comprises an operational amplification circuit; the homophase input pin of described operational amplification circuit forms the first voltage input end of described overvoltage crowbar; the out-phase input pin of described operational amplification circuit forms the second voltage input end of described overvoltage crowbar, and the output pin of described operational amplification circuit forms the voltage output end of described overvoltage crowbar.
4. overvoltage crowbar as claimed in claim 3; it is characterized in that; described input voltage circuit for detecting comprises: the second resistance and the 3rd resistance; one end of described second resistance is connected with the positive pole of described input circuit; the other end of described second resistance is via described 3rd grounding through resistance, and the out-phase input pin of described operational amplification circuit is connected between described second resistance and described 3rd resistance.
5. overvoltage crowbar as claimed in claim 3; it is characterized in that: described switching tube is the first diode; the output pin of described operational amplification circuit connects the negative electrode with described first diode, and the anode of described first diode turns off pin with the input undervoltage of the power supply control chip of described switching power circuit and is connected.
6. overvoltage crowbar as claimed in claim 3, it is characterized in that, also comprise one the 4th resistance, described 4th resistance is connected between the homophase input pin of described operational amplification circuit and the out-phase input pin of described operational amplification circuit.
7. an over-pressure safety device, it is characterized in that, comprise: overvoltage crowbar, input circuit and switching power circuit, described overvoltage crowbar is electrically connected between input circuit and switching power circuit, described overvoltage crowbar comprises the first voltage input end, second voltage input end, voltage output end, input voltage circuit for detecting, reference voltage provides circuit and switching tube, described reference voltage provides circuit for providing a reference voltage, described first voltage input end and described reference voltage provide circuit to be electrically connected, for receiving described reference voltage, described input voltage circuit for detecting is used for the input voltage of described input circuit to be converted to voltage to be compared, described second voltage input end and described input voltage circuit for detecting are electrically connected, for receiving described voltage to be compared, described overvoltage crowbar is by more described reference voltage and described voltage to be compared, and export a voltage control signal according to comparative result from described voltage output end, described voltage output end turns off pin by described switching tube with the input undervoltage of the power supply control chip of described switching power circuit and is connected,
When inputting described electric voltage over press to be compared, the voltage output end of described overvoltage crowbar exports described voltage control signal makes described switching power circuit quit work.
8. over-pressure safety device as claimed in claim 7; it is characterized in that: described reference voltage provides circuit to comprise the first voltage stabilizing didoe and the first resistance; the plus earth of described first voltage stabilizing didoe; the negative electrode of described first voltage stabilizing didoe is connected with the positive pole of described input circuit via described first resistance, and the first voltage input end of described overvoltage crowbar is connected between described voltage stabilizing didoe and described first resistance.
9. over-pressure safety device as claimed in claim 7; it is characterized in that: described overvoltage crowbar also comprises an operational amplification circuit; the homophase input pin of described operational amplification circuit forms the first voltage input end of described overvoltage crowbar; the out-phase input pin of described operational amplification circuit forms the second voltage input end of described overvoltage crowbar, and the output pin of described operational amplification circuit forms the voltage output end of described overvoltage crowbar.
10. over-pressure safety device as claimed in claim 9; it is characterized in that: described input voltage circuit for detecting comprises: the second resistance and the 3rd resistance; one end of described second resistance is connected with the positive pole of described input circuit; the other end of described second resistance is via described 3rd grounding through resistance, and the out-phase input pin of described operational amplification circuit is connected between described second resistance and described 3rd resistance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520956854.7U CN205160047U (en) | 2015-11-26 | 2015-11-26 | Overvoltage crowbar and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520956854.7U CN205160047U (en) | 2015-11-26 | 2015-11-26 | Overvoltage crowbar and device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN205160047U true CN205160047U (en) | 2016-04-13 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201520956854.7U Withdrawn - After Issue CN205160047U (en) | 2015-11-26 | 2015-11-26 | Overvoltage crowbar and device |
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| CN (1) | CN205160047U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105262054A (en) * | 2015-11-26 | 2016-01-20 | 四川汇源光通信有限公司 | Overvoltage protection circuit and device |
| CN109004359A (en) * | 2018-07-27 | 2018-12-14 | 北京小米移动软件有限公司 | Electronic equipment and its antenna structure, the adjusting method of aerial voltage, device |
-
2015
- 2015-11-26 CN CN201520956854.7U patent/CN205160047U/en not_active Withdrawn - After Issue
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105262054A (en) * | 2015-11-26 | 2016-01-20 | 四川汇源光通信有限公司 | Overvoltage protection circuit and device |
| CN105262054B (en) * | 2015-11-26 | 2017-12-12 | 四川汇源光通信有限公司 | Overvoltage crowbar and device |
| CN109004359A (en) * | 2018-07-27 | 2018-12-14 | 北京小米移动软件有限公司 | Electronic equipment and its antenna structure, the adjusting method of aerial voltage, device |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20160413 Effective date of abandoning: 20171212 |
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| AV01 | Patent right actively abandoned |