CN209913490U - Battery protection chip and battery system - Google Patents
Battery protection chip and battery system Download PDFInfo
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- CN209913490U CN209913490U CN201920886336.0U CN201920886336U CN209913490U CN 209913490 U CN209913490 U CN 209913490U CN 201920886336 U CN201920886336 U CN 201920886336U CN 209913490 U CN209913490 U CN 209913490U
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Abstract
The utility model discloses a battery protection chip, include: first pin, second pin, third pin and fourth pin for carry out charge-discharge protection to the battery, still including integrated inside the chip: the protection circuit is connected with the third pin; the drive circuit is connected with the protection circuit; the first switch tube is connected between the second pin and the fourth pin and used for connecting or disconnecting a charge and discharge path of the battery; and the substrate selection circuit is used for connecting the substrate of the first switch tube to one of the first path end and the second path end of the first switch tube according to the control signal. The utility model also discloses a battery system. Therefore, the external switch can be integrated into the chip, external elements are reduced, the space of a PCB (printed circuit board) is saved, and the surge tolerance of the chip is improved.
Description
Technical Field
The utility model relates to a battery protection field, concretely relates to battery protection chip and battery system.
Background
With the development of society and the continuous consumption of petrochemical energy, people are actively searching for new energy to replace the petrochemical energy which is exhausted in the whole day. Electric energy is one of ideal substitutes for petrochemical energy, so the demand of people for electric energy is higher and higher in recent years. With the development and popularization of unmanned electronic equipment, portable digital equipment, electric tools, electric vehicles and the like, the power core, namely a storage battery, is receiving more and more attention. The lithium battery is favored by manufacturers due to the advantages of high specific energy, long cycle life, small self-discharge, no memory effect, environmental protection and the like, and is one of the hot spots of power battery research. However, the lithium battery has a complicated internal structure and a complicated charge-discharge chemical reaction, and thus has many problems when used as a power source. First, lithium batteries cannot withstand overcharge and overdischarge; secondly, when the number of the series-parallel connection of the lithium batteries is large, the problems of unbalanced battery discharge and the like occur in the battery pack, and the battery pack needs to be subjected to balanced charge and discharge management; meanwhile, the lithium battery can only work within a certain range of current and a certain temperature range. When the lithium battery works under unsuitable conditions, such as conditions of overhigh temperature, overcharge, overdischarge, overlarge working current, short circuit of an external circuit and the like, the working efficiency of the lithium battery is reduced, the service life of the lithium battery is shortened, and the lithium battery is directly damaged if the working is serious. Therefore, in order to ensure the normal operation of the lithium battery, a protection circuit needs to be designed in the battery pack to protect the lithium battery.
At present, the single lithium battery protection chip of mainstream all is the structure of control chip plus discrete MOS switch tube, and more external devices are adopted to this kind of structure, and the cost is higher, occupies a large amount of PCB board spaces simultaneously, is unfavorable for the application in wearable equipment.
Therefore, there is a need to provide an improved solution to the above problems.
SUMMERY OF THE UTILITY MODEL
In order to solve the technical problem, the utility model provides a battery protection chip and battery system can be with inside the external switch is integrated to the chip, has reduced external element, has saved the PCB board space, has also improved the tolerance of chip to the surge simultaneously.
According to the utility model provides a pair of battery protection chip for carry out charge-discharge protection to the battery, include: the chip comprises a first pin, a second pin, a third pin and a fourth pin, wherein the first pin and the second pin are respectively used for connecting the positive electrode and the negative electrode of an external charging power supply or connecting the positive input port and the negative input port of an external load, and the chip is characterized by further comprising a first pin, a second pin, a third pin and a fourth pin which are integrated inside the chip: the protection circuit is connected with the third pin and used for outputting a corresponding control signal according to the charging and discharging voltage and/or current of the battery; the driving circuit is connected with the protection circuit and used for outputting a driving signal according to the control signal; the first switch tube is connected between the second pin and the fourth pin, and the control end receives the driving signal to connect or disconnect a charge and discharge passage of the battery; and the substrate selection circuit is respectively connected with the protection circuit and the first switch tube and is used for connecting the substrate of the first switch tube to one of a first path end and a second path end of the first switch tube according to the control signal, wherein the second path end is connected with the second pin.
Preferably, the battery protection chip further includes therein: a second resistor; and the second switching tube and the first switching tube are connected in series between the fourth pin and the second pin, and the control end of the second switching tube is connected with the first pin through the second resistor.
Preferably, the first switch tube and the second switch tube are NMOS transistors.
Preferably, the battery protection chip further includes therein: and the clamping circuit is connected with the second pin at one end, is connected with the first pin through the second resistor at the other end, and is used for clamping the voltage between the first pin and the second pin at the threshold when the voltage exceeds the threshold.
Preferably, the battery protection chip further includes therein: and the anode of the voltage stabilizing diode is connected with the second pin, and the cathode of the voltage stabilizing diode is connected with the first pin through the second resistor and is used for clamping the voltage between the first pin and the second pin at a threshold value when the voltage exceeds the threshold value.
Preferably, when the charging is over-voltage and/or over-current, the first switch tube is turned off, the substrate of the first switch tube is connected with the second path end, and the charging path of the battery is disconnected.
Preferably, when the discharging undervoltage and/or the discharging overcurrent occur, the first switching tube is turned off, the substrate of the first switching tube is connected with the first path end, and the discharging path of the battery is disconnected.
According to the utility model provides a pair of battery system, a serial communication port, include: a battery; a low-pass filter; and the battery protection chip, wherein the low-pass filter is connected in series with the positive and negative electrodes of the battery, the first pin of the battery protection chip is connected with the positive electrode of the battery, the fourth pin of the battery protection chip is connected with the negative electrode of the battery, and the third pin of the battery protection chip is connected with the low-pass filter.
Preferably, the low-pass filter includes a first resistor and a first capacitor connected in series, and the third pin of the battery protection chip is connected to the positive electrode of the battery through the first resistor and connected to the negative electrode of the battery through the first capacitor.
The utility model has the advantages that: the utility model discloses inside having integrateed the chip with external switch, reduced external component, saved the space of PCB board.
Meanwhile, the withstand voltage NMOS tube stack with small area and low voltage (such as 5V) is adopted to realize the withstand voltage of high voltage (such as 10V), the area of the chip is reduced, and the cost of the chip is reduced.
The chip is internally provided with a protection circuit and a substrate selection circuit, so that a charging and discharging passage of the battery can be cut off when the over-current or under-voltage of the charging/discharging of the battery is detected; the clamping circuit is arranged, so that after a charging path of the battery is cut off, the voltage of each port of the switching tube in the chip cannot exceed breakdown voltage, a current path is provided for a battery system, surge currents at the positive end and the negative end of the battery are absorbed, and the surge tolerance of the chip is improved.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.
Drawings
The above and other objects, features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings.
Fig. 1 is a schematic structural diagram of a battery system according to a first embodiment of the present invention;
fig. 2 shows a schematic structural diagram of a battery system according to a second embodiment of the present invention.
Detailed Description
In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. The preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
The present invention will be described in detail below with reference to the accompanying drawings.
Fig. 1 shows a schematic structural diagram of a battery system according to a first embodiment of the present invention.
As shown in fig. 1, in the present embodiment, the battery system 100 includes: the battery protection chip 110, the first resistor R1 and the first capacitor C1.
The battery protection chip 110 includes: a first lead 1, a second lead 2, a third lead 3 and a fourth lead 4. The first pin 1 of the battery protection chip 110 is a power VCC pin, the second pin 2 is a power VEE pin, the third pin 3 is a power VDD pin, and the fourth pin 4 is a power VSS.
In this embodiment, the third pin 3 and the fourth pin 4 may be used as detection pins for detecting the battery voltage. And meanwhile, a current monitoring point is also arranged in the chip to judge whether the battery Bat is charged in an overvoltage manner, charged in an overcurrent manner, discharged in an undervoltage manner or discharged in an overcurrent manner, so that the battery Bat is subjected to charge and discharge protection.
In this embodiment, the first pin 1 of the battery protection chip 110 is connected to the positive electrode P + of the battery pack, the second pin 2 is connected to the negative electrode P-of the battery pack, and the positive electrode P +/P-of the battery pack is connected to the positive electrode of the external charging power supply during charging or to the positive and negative input ports of the external load during discharging; meanwhile, the first pin 1 is also connected with the positive electrode of the battery Bat. The third pin 3 of the battery protection chip 110 is a power supply pin, and is connected to the positive electrode of the battery Bat through the first resistor R1, and is connected to the negative electrode of the battery Bat through the first capacitor C1. The fourth pin of the battery protected chip 110 is a ground pin and is connected to the negative electrode of the battery Bat.
Furthermore, a first resistor R1 and a first capacitor C1 are connected in series between the positive and negative ends of the battery Bat to form a low-pass filter to filter out high-frequency noise in the battery. The negative terminal of the battery Bat is connected to the fourth pin 4 of the battery protection chip 110 and then grounded.
The battery protection chip 110 further includes: the second resistor R2, the protection circuit 111, the driving circuit 112, the substrate selection circuit 113, the clamping circuit 114, the first switch tube MN1 and the second switch tube MN2 are integrated inside the chip.
The protection circuit 111 is connected with a third pin 3 of the battery protection chip 110, and is used for monitoring whether voltage of the battery Bat is abnormal during charging and discharging, and meanwhile, the protection circuit 111 is also connected with a point on a charging and discharging path of the battery in the chip, and is used for monitoring whether current of the battery Bat is abnormal during charging and discharging (such as whether charging overvoltage, charging overcurrent, discharging undervoltage, discharging overcurrent, short circuit and the like occur or not), and outputting a first control signal when the battery Bat is detected to be abnormal; outputting a second control signal when detecting that the battery Bat is abnormally charged; or outputs a third control signal when detecting that the battery Bat has abnormal discharge.
The driving circuit 112 is connected to the protection circuit 111 and the control end of the first switch tube MN1, receives the first control signal output by the protection circuit 111, and controls the first switch tube MN1 to be turned on; or receive the second control signal or the third control signal output by the protection circuit 111, and control the first switch tube MN1 to turn off.
The substrate selection circuit 113 is respectively connected to the first path terminal, the second path terminal and the substrate of the first switch tube MN1, and is also connected to the protection circuit 111, so as to receive the first control signal output by the protection circuit 111, and connect the substrate of the first switch tube MN1 to any path terminal of the first switch tube MN 1; receiving a second control signal output by the protection circuit 111, and connecting the substrate of the first switch tube MN1 to the second path end of the first switch tube MN 1; or receive the third control signal outputted by the protection circuit 111, and connect the substrate of the first switch tube MN1 to the first path end of the first switch tube MN 1.
Further, the first path terminal of the first switch tube MN1 is connected to the fourth pin 4 of the battery protection chip 110 through the second switch tube MN2, and the second path terminal thereof is connected to the second pin 2 of the battery protection chip 110.
One end of the clamp circuit 114 is connected to the second pin 2 of the battery protection chip 110, and the other end is connected to the first pin 1 of the battery protection chip 110 through the second resistor R2, and the clamp circuit 114 is activated when a voltage difference between the first pin 1 and the second pin 2 of the battery protection chip 110 (i.e., a voltage difference between the positive and negative ends of the battery pack) exceeds a certain threshold (e.g., 6.2V), so as to generate a clamp voltage, so as to maintain a voltage between the control end of the second switch MN2 in the battery protection chip 110 and the second pin 2 at a substantially constant state (e.g., at 6.2V).
The second switch tube MN2 and the first switch tube MN1 are connected in series between the fourth pin 4 and the second pin 2 of the battery protection chip 110 (the first path end of the second switch tube MN2 is connected to the fourth pin 4 of the battery protection chip 110, the second path end is connected to the first path end of the first switch tube MN 1), the control end of the second switch tube MN2 is connected to the first pin 1 of the battery protection chip 110 through the second resistor R2 and the clamp circuit, and is connected to the second pin 2 of the battery protection chip 110 through the clamp circuit 114. Therefore, the second switch MN2 is in a substantially constant on state in the chip 110, and the drive circuit 112 controls the on/off of the charge/discharge path of the battery Bat by controlling the on/off of the first switch MN 1.
Furthermore, the connection point of the second switch tube MN2 and the first switch tube MN1 is the current monitoring point of the battery, and is connected to the protection circuit 111.
In this embodiment, the first switch tube MN1 and the second switch tube MN2 are both low-voltage (e.g., 5V) withstand voltage NMOS transistors with small areas, and the withstand voltages of the first switch tube MN1 and the second switch tube MN2 are overlapped by connecting the first switch tube MN1 and the second switch tube MN2 in series, so that a high-voltage (e.g., 10V) withstand voltage can be realized, the area of the chip itself can be reduced, and the cost of the chip itself can be reduced. Furthermore, the withstand voltage of the battery protection chip is distributed to the two NMOS transistors, so that a single chip cannot bear too much withstand voltage, and the service life of the chip is prolonged.
In this embodiment, in a normal state, the driving circuit 112 turns on the first switch tube MN1 to connect the charge/discharge path of the battery Bat; in the protection state, the drive circuit 112 cooperates with the substrate selection circuit 113 to shut off the charge/discharge path of the battery Bat.
Specifically, when the charging or discharging process of the battery Bat is not abnormal, the protection circuit 111 sends a first control signal, and the driving circuit 112 receives the first control signal and outputs a first driving signal to drive the first switch tube MN1 to open, so as to communicate with the charging/discharging path of the battery Bat.
When the condition of over-voltage charging or over-current charging of the battery Bat is triggered, the protection circuit 111 sends a second control signal, the driving circuit 112 receives the second control signal and outputs a second driving signal to drive the first switch tube MN1 to be turned off, and the substrate selection circuit 113 connects the substrate of the first switch tube MN1 to the negative terminal of the battery pack according to the second control signal (at this time, the anode of the parasitic diode of the first switch tube MN1 is connected to the second pin 2 of the battery protection chip 110, and the cathode is connected to the fourth pin 4 of the battery protection chip 110), so as to cut off the charging path of the battery Bat.
When the conditions of undervoltage, discharge overcurrent or short circuit of the battery Bat are triggered, the protection circuit 111 sends a third control signal, the driving circuit 112 receives the third control signal and outputs a second driving signal to drive the first switching tube MN1 to be turned off, and the substrate selection circuit 113 connects the substrate of the first switching tube MN1 to the middle point of the first switching tube MN1 and the second switching tube MN2 according to the third control signal (at this time, the anode of the parasitic diode of the first switching tube MN1 is connected to the fourth pin 4 of the battery protection chip 110, and the cathode is connected to the second pin 2 of the battery protection chip 110), so as to cut off the discharge path of the battery Bat.
Further, when the battery Bat voltage is triggered to be over-voltage or the charging current is over-current to cut off the charging path of the battery Bat, the charger connected to the positive and negative terminals of the battery pack may raise the voltage of the positive and negative ports of the battery board to a high voltage (e.g., 10V), and at this time, the clamping circuit 114 may be activated to keep the clamping voltage at a substantially constant state (e.g., 6.2V), so as to ensure that the voltage difference between the ports of the first switch tube MN1 and the second switch tube MN2 does not exceed the breakdown voltage. Meanwhile, the clamping circuit 114 can also provide a current path, so that the surge current at the positive end and the negative end of the battery pack can be absorbed, and the surge tolerance of the battery system is provided.
The embodiment reduces the external elements of the battery system and saves the space of the PCB; meanwhile, the area of the chip is reduced, the cost of the chip is reduced, and the surge tolerance of the chip is improved, so that the voltage of each port of a plurality of switching tubes in the chip cannot exceed the breakdown voltage.
Fig. 2 shows a schematic structural diagram of a battery system according to a second embodiment of the present invention.
As shown in fig. 2, in the second embodiment of the present invention, the structure of the battery system 200 is substantially the same as that of the battery system 100 in the first embodiment, and the same parts can be referred to fig. 1 and will not be described again.
In contrast, in the second embodiment, the clamp circuit 114 in the first embodiment is replaced with a zener diode ZD 1. In the battery system 200, the anode of the zener diode ZD1 is connected to the second pin 2 of the battery protection chip 210, and the cathode thereof is connected to the first pin 1 of the battery protection chip 210 through the second resistor R2. The zener diode ZD1 is used to maintain the voltage between the control terminal of the second switching tube MN2 and the second pin 2 in a substantially constant state when the voltage between the first pin and the second pin of the battery protection chip 210 exceeds a threshold value.
In this embodiment, the zener diode ZD1 is used to make the response speed of the battery system faster, but the corresponding process cost is increased.
It should be noted that, the voltage clamping schemes for the positive electrode and the negative electrode of the battery pack of the present invention include, but are not limited to, the schemes disclosed in the two embodiments, and all the alternatives that can be conceived by those skilled in the art without creative efforts are within the scope of the present invention.
It should be noted that, in this document, the contained terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element. Also, the terms "connected," "connecting," and the like are used herein to denote electrical connection, either direct or indirect, unless otherwise indicated.
Finally, it should be noted that: it should be understood that the above examples are only for clearly illustrating the present invention and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious changes and modifications may be made without departing from the scope of the present invention.
Claims (9)
1. A battery protection chip for charging and discharging protection of a battery, comprising: a first lead, a second lead, a third lead and a fourth lead,
the first pin and the second pin are respectively used for connecting the positive pole and the negative pole of an external charging power supply or connecting the positive input port and the negative input port of an external load,
it is characterized in that the chip also comprises:
the protection circuit is connected with the third pin and used for outputting a corresponding control signal according to the charging and discharging voltage and/or current of the battery;
the driving circuit is connected with the protection circuit and used for outputting a driving signal according to the control signal;
the first switch tube is connected between the second pin and the fourth pin, and the control end receives the driving signal to connect or disconnect a charge and discharge passage of the battery;
a substrate selection circuit respectively connected with the protection circuit and the first switch tube and used for connecting the substrate of the first switch tube to one of the first path end and the second path end of the first switch tube according to the control signal,
wherein the second via end is connected to the second pin.
2. The battery protection chip of claim 1, further comprising:
a second resistor; and
and the second switching tube and the first switching tube are connected in series between the fourth pin and the second pin, and the control end of the second switching tube is connected with the first pin through the second resistor.
3. The battery protection chip of claim 2, wherein the first and second switching transistors are NMOS transistors.
4. The battery protection chip of claim 2, further comprising:
and the clamping circuit is connected with the second pin at one end, is connected with the first pin through the second resistor at the other end, and is used for clamping the voltage between the first pin and the second pin at the threshold when the voltage exceeds the threshold.
5. The battery protection chip of claim 2, further comprising:
and the anode of the voltage stabilizing diode is connected with the second pin, and the cathode of the voltage stabilizing diode is connected with the first pin through the second resistor and is used for clamping the voltage between the first pin and the second pin at a threshold value when the voltage exceeds the threshold value.
6. The battery protection chip of claim 1,
when the charging is over-voltage and/or over-current, the first switch tube is turned off, the substrate of the first switch tube is connected with the second path end, and the charging path of the battery is disconnected.
7. The battery protection chip of claim 1,
when the discharging undervoltage and/or the discharging current is over-current, the first switch tube is turned off, the substrate of the first switch tube is connected with the first path end, and the discharging path of the battery is disconnected.
8. A battery system, comprising:
a battery;
a low-pass filter; and
the battery protection chip of any one of claims 1 to 7,
wherein the low-pass filter is connected in series with the anode and the cathode of the battery,
the first pin of the battery protection chip is connected with the anode of the battery, the fourth pin of the battery protection chip is connected with the cathode of the battery,
and a third pin of the battery protection chip is connected with the low-pass filter.
9. The battery system of claim 8, wherein the low pass filter comprises a first resistor and a first capacitor connected in series, and the third pin of the battery protection chip is connected to the positive pole of the battery through the first resistor and connected to the negative pole of the battery through the first capacitor.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920886336.0U CN209913490U (en) | 2019-06-13 | 2019-06-13 | Battery protection chip and battery system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201920886336.0U CN209913490U (en) | 2019-06-13 | 2019-06-13 | Battery protection chip and battery system |
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| CN209913490U true CN209913490U (en) | 2020-01-07 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114487761A (en) * | 2020-10-27 | 2022-05-13 | 圣邦微电子（北京）股份有限公司 | Polling detection circuit and method based on battery protection chip and battery protection chip |
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2019
- 2019-06-13 CN CN201920886336.0U patent/CN209913490U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114487761A (en) * | 2020-10-27 | 2022-05-13 | 圣邦微电子（北京）股份有限公司 | Polling detection circuit and method based on battery protection chip and battery protection chip |
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