CN204302368U - Over-current detection circuit and overcurrent detecting device - Google Patents
Over-current detection circuit and overcurrent detecting device Download PDFInfo
- Publication number
- CN204302368U CN204302368U CN201420834402.7U CN201420834402U CN204302368U CN 204302368 U CN204302368 U CN 204302368U CN 201420834402 U CN201420834402 U CN 201420834402U CN 204302368 U CN204302368 U CN 204302368U
- Authority
- CN
- China
- Prior art keywords
- circuit
- input
- over
- battery
- overcurrent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
- Secondary Cells (AREA)
- Protection Of Static Devices (AREA)
Abstract
The utility model provides a kind of over-current detection circuit and overcurrent detecting device, solves in over-current detection of the prior art and there is delayed technical problem.Circuit comprises battery, comparison circuit, bleeder circuit and the first electric capacity; Anode one tunnel of battery connects the input of bleeder circuit, and the output of bleeder circuit connects the first input end of comparison circuit; Another road of the anode of battery connects the second input of comparison circuit; First electric capacity one end is connected between the anode of battery and the second input of comparison circuit, other end ground connection.Based on the feature that the internal resistance of cell is constant, when not having overcurrent to occur, the first input end input of comparison circuit changes with the comparison inputted when there is overcurrent with the input comparison of the second input, thus the output of comparison circuit also changes, circuit can be characterized based on this change and occur overcurrent, and not powered tolerance limit system generation detects delayed, realizes detecting overcurrent in real time, effectively avoids the infringement of overcurrent to circuit.
Description
Technical field
The utility model relates to current detection technology field, particularly relates to the overcurrent detecting device of a kind of over-current detection circuit and this over-current detection circuit of use.
Background technology
The factor producing over-current phenomenon avoidance in the circuit of electronic equipment is a lot, typically occurs short circuit phenomenon in such as circuit, causes circuitous resistance too small, and thus operating current increases generation over-current phenomenon avoidance.When circuit produces over-current phenomenon avoidance, can damage circuit and components and parts, therefore over-current detection is the important content in circuit design.
Current over-current detection is all series resistance on power circuit, realizes over-current detection by the change detecting resistance; But, power circuit all can exist the electric capacity of large capacitance, due to the energy storage characteristic of electric capacity, even if when having big current to occur in circuit, also the hysteresis quality of detection can be caused because of the existence of bulky capacitor, that is, when there being over-current phenomenon avoidance to occur, due to the energy storage of bulky capacitor, voltage can not immediately along with the change of electric current changes greatly, cause detection delayed, within the delayed time period, overcurrent has probably had an impact to circuit and has caused circuit to damage.
Summary of the invention
By providing a kind of crossing detector circuit and overcurrent detecting device, there is delayed technical problem to solve in over-current detection of the prior art in the embodiment of the present application.
For solving the problems of the technologies described above, the embodiment of the present application is achieved by the following technical solutions:
Propose a kind of over-current detection circuit, comprise battery, comparison circuit, bleeder circuit and the first electric capacity; Anode one tunnel of described battery connects the input of described bleeder circuit, and the output of described bleeder circuit connects the first input end of described comparison circuit, and described bleeder circuit also has earth terminal; Another road of the anode of described battery connects the second input of described comparison circuit; Described first electric capacity one end is connected between the anode of described battery and the second input of comparison circuit, other end ground connection.
Further, described comparison circuit is comparator; The first input end of described comparison circuit is the in-phase input end of described comparator, and the second input of described comparison circuit is the inverting input of described comparator.
Further, described bleeder circuit is made up of the first resistance and the second resistance; The first end of described first resistance connects the anode of described battery, and the second end of described first resistance connects the first end of described second resistance, and the second end of described second resistance connects described earth terminal; The input of described bleeder circuit is the first end of described first resistance, and the output of described bleeder circuit is the second end of described first resistance.
Further, described battery is dry cell, lithium battery or Ni-MH battery.
Further, the joint number of described battery is at least one joint.
Also propose a kind of overcurrent detecting device, comprise control circuit and above-mentioned over-current detection circuit; The output of the comparison circuit in described over-current detection circuit connects the input of described control circuit; Described control circuit receives the output signal of the output of described comparison circuit, and according to described output signal output overcurrent index signal.
Compared with prior art, the technical scheme that the embodiment of the present application provides, the technique effect had or advantage are: the embodiment of the present application propose over-current detection circuit and overcurrent detecting device in, utilize the feature that the internal resistance of cell is constant, bleeder circuit is connected at the anode of battery, voltage after dividing potential drop is as the first input of comparison circuit, and the voltage of battery positive is as the second input of comparison circuit, and the anode of this battery is connected with the first electric capacity over the ground; When there is over-current phenomenon avoidance in circuit, because the internal resistance of battery is constant, the voltage instantaneous that then battery positive exports increases, voltage after dividing potential drop is also increased, then the first input of comparison circuit increases instantaneously, and because there is the existence of electric capacity, based on the energy storage characteristic of electric capacity, the voltage that battery positive increases instantaneously can not be embodied in the second input of comparison circuit, makes second of comparison circuit the input still remain on battery normal output voltage; Therefore, when occurring over-current phenomenon avoidance, the first input of comparison circuit is greater than the second input, and this inputs just in time contrary with the second state inputted with first when not there is over-current phenomenon avoidance; When there is not over-current phenomenon avoidance, due to the dividing potential drop of bleeder circuit, the first input is less than the second input; First input changes with the second magnitude relationship inputted, cause the change that comparison circuit exports, based on the change of this output, an over-current signal can be produced immediately characterize and occur over-current phenomenon avoidance, this sign is real-time, hysteresis quality can not be there is because of electric capacity, effectively avoid the infringement of overcurrent to circuit.
Accompanying drawing explanation
Fig. 1 is the circuit framework figure of the over-current detection circuit that the embodiment of the present application proposes;
Fig. 2 is the circuit diagram of the over-current detection circuit that the embodiment of the present application proposes.
Detailed description of the invention
The embodiment of the present application, by providing a kind of over-current detection circuit, device and over-current detecting method, solves in over-current detection of the prior art and there is delayed technical problem; Based on the feature that the internal resistance of cell is constant, can over-current signal be produced in the moment of circuit overcurrent, effectively avoid the circuit damage caused because detection is delayed.
In order to better understand technique scheme, below in conjunction with Figure of description and concrete embodiment, technique scheme is described in detail.
As shown in Figure 1, be the circuit structure diagram of the over-current detection circuit that the embodiment of the present application proposes, comprise battery Bat, comparison circuit U1, bleeder circuit D1 and the first electric capacity C1; Anode one tunnel of battery connects the input of bleeder circuit, and the output of bleeder circuit connects the first input end of comparison circuit, and bleeder circuit also has earth terminal; Another road of the anode of TV connects the second input of comparison circuit 12; First electric capacity one end is connected between the anode of battery and the second input of comparison circuit, other end ground connection.
When circuit normally works, battery positive voltage V is directly added in the second input of comparison circuit, and in bleeder circuit dividing potential drop, the dividing potential drop of output is V1; V1 is added on the first input end of comparison circuit, V1<V, then export at the output of comparison circuit the non-over-current signal that a sign do not have overcurrent to produce; When there is short circuit in circuit or other faults produce over-current phenomenon avoidance, constant due to the internal resistance of cell, it is increased to V2 instantaneously at the output voltage of battery positive, then V1 also increases, the V1 increased is added on the first input end of comparison circuit, and at the second input of comparison circuit, due to the energy storage characteristic of the first electric capacity, make the voltage of the second input can not increase to V2 instantaneously along with the increase of electric current, but want delayed a period of time, during this period of time, the second input terminal voltage of comparison circuit is still V.
By rationally arranging the dividing ratios relation of bleeder circuit, can make when producing overcurrent, the transient voltage V2 being added in comparison circuit first input end is greater than normal battery operation output voltage V, when then there is overcurrent, the comparative voltage relation of comparison circuit two inputs changes, namely, the second input terminal voltage is less than by first input end voltage, be changed to first input end voltage and be greater than the second input terminal voltage, this change makes the output signal of the output of comparison circuit change, and the output signal after change is the over-current signal characterizing overcurrent and occur.
The change of the output signal of above-mentioned comparison circuit output occurs at once producing along with overcurrent, can not produce to detect delayed because of the existence of electric capacity, can effectively avoid overcurrent to the infringement of circuit.
As shown in Figure 2, be the specific embodiment that the embodiment of the present application proposes, in this over-current detection circuit, bleeder circuit U1 is made up of the first resistance R1 and the second resistance R2; The first end of the first resistance R1 connects the anode of battery, and the second end of the first resistance connects the first end of the second resistance R2, the second end ground connection of the second resistance; The input of bleeder circuit is the first end of the first resistance, and the output of bleeder circuit is the second end of the first resistance.In figure, power conversion chip U2 is for generation of stable operating voltage VCC.
When circuit normally works, battery positive voltage V is directly added in the second input of comparison circuit, and dividing potential drop in the bleeder circuit that the first resistance R1 and the second resistance R2 forms, be V1=V*R2/ (R1+R2) at the voltage of the first resistance R1 second end, V1 is added on the first input end of comparison circuit, V1<V, then export at the output of comparison circuit the non-over-current signal that a sign do not have overcurrent to produce; When there is short circuit in circuit or other faults produce over-current phenomenon avoidance, constant due to the internal resistance of cell, it is increased to V2 instantaneously at the output voltage of battery positive, now, V1=V2*R2/ (R1+R2), the V1 increased is added on the first input end of comparison circuit, and at the second input of comparison circuit, due to the energy storage characteristic of the first electric capacity, make the voltage of the second input can not increase to V2 instantaneously along with the increase of electric current, but want delayed a period of time, during this period of time, the second input terminal voltage of comparison circuit is still V.
By rationally arranging the proportionate relationship of the first resistance R1 and the second resistance R2, can make when producing overcurrent, the transient voltage V2 being added in comparison circuit first input end is greater than normal battery operation output voltage V, when then there is overcurrent, the comparative voltage relation of comparison circuit two inputs changes, namely, the second input terminal voltage is less than by first input end voltage, be changed to first input end voltage and be greater than the second input terminal voltage, this change makes the output signal of the output of comparison circuit change, output signal after change is the over-current signal characterizing overcurrent and occur.
As shown in Figure 2, comparison circuit adopts comparator u1 to realize, then the first input end of comparison circuit is the in-phase input end of comparator, and the second input of comparison circuit is the inverting input of comparator; When not having overcurrent to produce, in-phase input end voltage is less than anti-phase input terminal voltage, comparator output low level signal, characterizes in circuit and does not occur overcurrent; When producing overcurrent in circuit, in-phase input end voltage is greater than anti-phase input terminal voltage, and comparator output terminal exports high level signal, and this high level signal or variable signal are from low to high the over-current signal characterizing overcurrent and produce.
The over-current detection that the embodiment of the present application proposes is based on the constant feature of the internal resistance of cell, and therefore this battery generally adopts dry cell, lithium battery or Ni-MH battery etc. to possess the battery of the constant feature of internal resistance.
Battery can be single-unit, also can be the battery pack of multiple batteries composition.
Based on above-mentioned over-current detection circuit, the embodiment of the present application also proposes a kind of overcurrent detecting device, and this device comprises control circuit and over-current detection circuit; The input of the output connection control circuit of the comparison circuit in over-current detection circuit; Control circuit receives the output signal of the output of comparison circuit from its input, and according to this output signal output overcurrent index signal.
The output signal that control circuit receives from the output of comparison circuit, or for characterizing the non-over-current signal not having overcurrent, or for characterizing the over-current signal that overcurrent occurs, based on these two kinds of signals, control circuit produces and exports an overcurrent index signal, receives MCU or other circuit of this overcurrent index signal, can adopt an effective measure, timely process, avoids because detecting the delayed impact on circuit and damage.
The embodiment of the present application propose over-current detection circuit and overcurrent detecting device in, when there is not overcurrent in circuit, battery positive voltage by export after bleeder circuit dividing potential drop first input be less than the second input; And when overcurrent appears in circuit, battery positive voltage instantaneous increases, first input is increased instantaneously, and the second input is due to the energy storage characteristic of electric capacity, it increases process lag, and in the delayed time period, the first input is greater than the second input, then when detecting that the first input is greater than the second input, producing and exporting an overcurrent index signal.
Or when overcurrent does not appear in circuit, battery positive voltage is less than the second input by the first input exported after bleeder circuit dividing potential drop; And when overcurrent appears in circuit, battery positive voltage instantaneous increases, the first input is increased instantaneously, and the second input is due to the energy storage characteristic of electric capacity, it increases process lag, and in the delayed time period, the first input is greater than the second input.
So, before circuit generation overcurrent and when there is overcurrent, first input there occurs change with the second comparison inputted, the second input is less than by the first input, become the first input and be greater than the second input, then comparative result also can change, such as, become high level from low level, or becomes low level from high level; Then when change comparative result being detected, produce and export an overcurrent index signal.
The over-current detection circuit proposed by the embodiment of the present application and overcurrent detecting device, can realize adopting simple circuit design to realize the real-time detection of overcurrent, avoid the circuit damage caused because detection is delayed, effectively solve over-current detection in prior art and there is delayed technical problem.
It should be noted that; above-mentioned explanation is not to restriction of the present utility model; the utility model is also not limited in above-mentioned citing; the change that those skilled in the art make in essential scope of the present utility model, modification, interpolation or replacement, also should belong to protection domain of the present utility model.
Claims (6)
1. over-current detection circuit, comprises battery, it is characterized in that, described over-current detection circuit also comprises comparison circuit, bleeder circuit and the first electric capacity; Anode one tunnel of described battery connects the input of described bleeder circuit, and the output of described bleeder circuit connects the first input end of described comparison circuit, and described bleeder circuit also has earth terminal; Another road of the anode of described battery connects the second input of described comparison circuit; Described first electric capacity one end is connected between the anode of described battery and the second input of comparison circuit, other end ground connection.
2. over-current detection circuit according to claim 1, is characterized in that, described comparison circuit is comparator; The first input end of described comparison circuit is the in-phase input end of described comparator, and the second input of described comparison circuit is the inverting input of described comparator.
3. over-current detection circuit according to claim 1, is characterized in that, described bleeder circuit is made up of the first resistance and the second resistance; The first end of described first resistance connects the anode of described battery, and the second end of described first resistance connects the first end of described second resistance, and the second end of described second resistance connects described earth terminal; The input of described bleeder circuit is the first end of described first resistance, and the output of described bleeder circuit is the second end of described first resistance.
4. testing circuit according to claim 1, is characterized in that, described battery is dry cell, lithium battery or Ni-MH battery.
5. the over-current detection circuit according to claim 1 or 4, is characterized in that, the joint number of described battery is at least one joint.
6. overcurrent detecting device, is characterized in that, comprises control circuit and the over-current detection circuit as described in any one of claim 1-5 claim; The output of the comparison circuit in described over-current detection circuit connects the input of described control circuit; Described control circuit receives the output signal of the output of described comparison circuit, and according to described output signal output overcurrent index signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420834402.7U CN204302368U (en) | 2014-12-25 | 2014-12-25 | Over-current detection circuit and overcurrent detecting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420834402.7U CN204302368U (en) | 2014-12-25 | 2014-12-25 | Over-current detection circuit and overcurrent detecting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204302368U true CN204302368U (en) | 2015-04-29 |
Family
ID=53107899
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420834402.7U Active CN204302368U (en) | 2014-12-25 | 2014-12-25 | Over-current detection circuit and overcurrent detecting device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204302368U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104459290A (en) * | 2014-12-25 | 2015-03-25 | 青岛歌尔声学科技有限公司 | Overcurrent detection circuit, device and method |
| CN109613327A (en) * | 2019-01-09 | 2019-04-12 | 成都秦川物联网科技股份有限公司 | Circuit board overcurrent detecting device and method |
-
2014
- 2014-12-25 CN CN201420834402.7U patent/CN204302368U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104459290A (en) * | 2014-12-25 | 2015-03-25 | 青岛歌尔声学科技有限公司 | Overcurrent detection circuit, device and method |
| CN109613327A (en) * | 2019-01-09 | 2019-04-12 | 成都秦川物联网科技股份有限公司 | Circuit board overcurrent detecting device and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105372480A (en) | Over voltage, under voltage and phase failure detection circuit for charging pile | |
| CN106501611A (en) | Insulation resistance detection method and device | |
| CN202931282U (en) | General telecommand acquisition module for distribution network terminal | |
| CN102777665B (en) | Solenoid valve control circuit and solenoid valve switch-in self-checking method thereof | |
| CN103872667A (en) | Circuit current differential protection method preventing abnormal large number of combination unit | |
| CN105680520A (en) | Discharging current hardware protection circuit for vehicle-mounted lithium battery pack of electric vehicle | |
| CN102662121A (en) | System and method for detecting failure of super capacitor module | |
| CN105514932A (en) | Short circuit protection circuit of power supply | |
| CN105044555A (en) | High voltage direct current power transmission line fault pole discrimination method by utilization of single pole electric quantity | |
| CN204302368U (en) | Over-current detection circuit and overcurrent detecting device | |
| CN103683266B (en) | Rechargeable battery protection circuit | |
| CN202997539U (en) | A super capacitor voltage balance protection circuit | |
| CN205489684U (en) | Intelligence power battery | |
| CN203707754U (en) | PFC current protection and control circuit, and electrical equipment | |
| CN104078950B (en) | Ultra-high voltage transmission line relay protection method based on positive-sequence break variable differential coefficient matrix | |
| CN202708270U (en) | Electromagnetic valve control circuit | |
| CN204012767U (en) | A kind of charging and discharging lithium battery management circuit and lithium battery management system | |
| CN203607846U (en) | Rechargeable battery protection circuit | |
| CN204925291U (en) | Circuit board falls electrical detection circuitry | |
| CN201828602U (en) | Power failure detection circuit with low power consumption | |
| CN104459290A (en) | Overcurrent detection circuit, device and method | |
| CN203595772U (en) | Inverter short circuit overload detection circuit and vehicle inverter | |
| CN204758768U (en) | IGBT overflows failure detector circuit | |
| CN204131110U (en) | Based on the battery system anti-surge circuit of discrete elements | |
| CN207007931U (en) | The overvoltage undervoltage detection circuit and Switching Power Supply of Switching Power Supply |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |