Battery protection circuit, battery protection board, electronic device, and control method

Abstract

The application provides a battery protection circuit, comprising a power supply end, a power ground end, a main control unit and a main switch unit; the battery protection circuit further comprises a power-on detection module and an anti-disassembly storage unit; the power-on detection module is used for detecting whether the battery protection circuit is powered on; the main control unit is connected with the power-on detection module and the anti-disassembly storage unit respectively; when the power-on detection module detects that the battery protection circuit is powered on, it outputs a power-on signal to the main control unit; the main control unit reads first information stored in the anti-disassembly storage unit, compares the first information with first preset information, and outputs battery replacement information if the comparison result meets first preset conditions; if the comparison result does not meet the first preset conditions, the main control unit outputs the first preset information to the anti-disassembly storage unit. The application further provides a battery protection board, an electronic device and a control method.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of battery protection, in particular to a battery protection circuit, a battery protection board, an electronic device and a control method. BACKGROUND

[0002] Battery packs are widely used in electronic devices, such as mobile phones, tablet computers, Bluetooth earphones, electronic toys, etc., to provide a more flexible use environment for electronic devices without being limited by the range of sockets and power supply wires. Generally speaking, a battery pack includes a battery and a battery protection board, the battery is used to provide energy for the electronic device, and the battery protection board is generally wrapped together with the battery pack, the battery protection board includes a printed circuit board, a battery protection circuit and related components mounted on the printed circuit board, and the battery protection circuit is used to protect the battery from overcharging or overdischarging and other abnormal situations. The electronic device also includes a system circuit, and the battery supplies power to the system circuit through the battery protection circuit.

[0003] In order to prevent the replacement of the battery in the electronic device that has passed official certification with a poor performance fake battery (not passed official certification), which can easily cause safety problems, the battery protection circuit of the prior art includes a first authentication unit, and the system circuit includes a second authentication unit, the first authentication unit and the second authentication unit communicate with each other to verify whether the battery in the battery pack is an officially certified battery. However, there are now battery packs for electronic devices that are disassembled and the battery of the battery pack is separated from the battery protection board, and the officially certified battery is replaced with a fake battery, and the fake battery and the genuine battery protection board are assembled and installed on the electronic device. Since the first authentication unit is located on the battery protection board and the second authentication unit is located on the system circuit, the authentication of the battery pack and the system circuit can pass, but since the fake battery is replaced, the electronic device is prone to safety problems during use, and users are not easy to detect that the certified battery has been replaced, which can also affect the manufacturer's brand. SUMMARY

[0004] The technical problem to be solved by the embodiments of the present application is to provide a battery protection circuit, a battery protection board, a battery pack, an electronic device and a control method in view of the deficiencies of the prior art. The situation that the battery is replaced can be reminded.

[0005] To solve the above technical problems, the first aspect of the embodiment of the present application provides a battery protection circuit, comprising: a power supply end, a power ground end, an overcharge protection unit, an overdischarge protection unit, a main control unit, and a main switch unit, wherein the power supply end and the power ground end are used to be connected with a battery, a control end of the main switch unit is electrically connected with the main control unit, one end of the main switch unit is used to be electrically connected with the power supply end or the power ground end, and the other end of the main switch unit is used to be electrically connected with a system circuit, and the main switch unit is used to control the battery to supply power to the system circuit.

[0006] The battery protection circuit further comprises a power-on detection module and an anti-disassembly storage unit, the power-on detection module is connected with the power supply end and the power ground end respectively, the power-on detection module is used to detect whether the battery protection circuit is powered on, the main control unit is connected with the power-on detection module and the anti-disassembly storage unit respectively, when the power-on detection module detects that the battery protection circuit is powered on, the power-on detection module outputs a power-on signal to the main control unit, the main control unit reads first information stored in the anti-disassembly storage unit, compares the first information with first preset information, if a comparison result meets a first preset condition, the main control unit outputs battery replacement information, and the battery replacement information is used to indicate that the battery is replaced, if the comparison result does not meet the first preset condition, the main control unit outputs the first preset information to the anti-disassembly storage unit, and the anti-disassembly storage unit stores the first preset information as the first information.

[0007] Optionally, the first preset condition comprises that the first information is the same as the first preset information.

[0008] Optionally, the battery protection circuit further comprises a battery information storage unit and a battery information acquisition unit, the battery information acquisition unit and the battery information storage unit are connected with the main control unit, and the battery information storage unit is used to store battery information before power-off.

[0009] If the comparison result meets the first preset condition, the main control unit obtains current battery information via the battery information acquisition unit, compares the current battery information with battery information stored in the battery information storage unit, and outputs the battery replacement information if a comparison result meets a second preset condition.

[0010] Optionally, the second preset condition is that a difference between the current battery information and the stored battery information is greater than or equal to a preset value.

[0011] Optionally, when the power-on detection module detects that a time length during which the power-on detection module is connected with the battery is greater than or equal to a first preset time length, the power-on detection module outputs the power-on signal to the main control unit.

[0012] Optionally, the battery protection circuit comprises a first authentication unit, and the first authentication unit is configured to communicate with a second authentication unit of a system circuit to verify whether the battery is an original battery.

[0013] Optionally, the battery protection circuit is located on the same chip; or,

[0014] The elements of the battery protection circuit except the main switch unit are located on one chip, and the main switch unit is located on another chip; or,

[0015] The elements of the battery protection circuit except the first authentication unit are located on one chip; or,

[0016] The elements of the battery protection circuit except the main switch unit and the first authentication unit are located on one chip; or,

[0017] The battery protection circuit verifies whether the battery is replaced after verifying that the battery is an original battery.

[0018] The second aspect of the embodiment of the present application provides a battery protection board, comprising:

[0019] A printed circuit board;

[0020] The battery protection circuit described above is mounted on the printed circuit board.

[0021] The third aspect of the embodiment of the present application provides a battery pack, comprising:

[0022] A battery;

[0023] The battery protection circuit described above, or the battery protection board described above, wherein a power supply end of the battery protection circuit is connected to a positive electrode of the battery, and a power supply ground end of the battery protection circuit is connected to a negative electrode of the battery.

[0024] The fourth aspect of the embodiment of the present application provides an electronic device, comprising:

[0025] A system circuit;

[0026] The battery protection circuit described above, or the battery protection board described above, or the battery pack described above, wherein the system circuit is configured to be connected to the battery via the battery protection circuit.

[0027] The fifth aspect of the embodiment of the present application provides a control method of a battery protection circuit, comprising:

[0028] Obtaining a power-on signal;

[0029] Reading first information in an anti-disassembly storage unit;

[0030] Comparing the first information with first preset information;

[0031] If the comparison result meets the first preset condition, battery replacement information is output, the battery replacement information being used to indicate that the battery is replaced;

[0032] If the comparison result does not meet the first preset condition, first preset information is output to the anti-disassembly storage unit, and the anti-disassembly storage unit stores the first preset information as the first information.

[0033] The battery protection circuit of the embodiment includes a power-on detection module and an anti-disassembly storage unit. When the power-on detection module detects that the battery protection circuit is powered on, it outputs a power-on signal to the main control unit. The main control unit reads the first information stored in the anti-disassembly storage unit and compares the first information with the first preset information. If the comparison result meets the first preset condition, the main control unit outputs battery replacement information, which is used to indicate that the battery is replaced. If the comparison result does not meet the first preset condition, the main control unit outputs the first preset information to the anti-disassembly storage unit, and the anti-disassembly storage unit stores the first preset information as the first information. Through such processing, when the battery protection circuit is powered on for the first time, the first information stored in the anti-disassembly storage unit is empty information or non-first preset information. The main control unit determines that the comparison result does not meet the first preset condition. The main control unit outputs the first preset information to the anti-disassembly storage unit, and the anti-disassembly storage unit stores the first preset information as the first information. When the battery protection board is disassembled from the original battery and the battery protection circuit is powered on again, this is the second time or more times of power-on. At this time, it is very likely that the original battery is replaced with a poor-quality battery. At this time, the first information stored in the anti-disassembly storage unit is the first preset information. The main control unit determines that the comparison result meets the first preset condition. At this time, the main control unit outputs the battery replacement information. Through the battery replacement information, the user can know that the battery may be replaced / stolen with a poor-quality battery. This can prevent the battery of the electronic device from being maliciously replaced, is conducive to improving the safety of the user using the electronic device, reducing the probability of a safety accident of the battery, and reducing the user's confusion. Moreover, through the battery replacement information, the factory end can also know that the battery may be replaced. This is also convenient for the manufacturer to maintain the electronic device in the future and can prevent damage to their own brand. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application. Those skilled in the art can also obtain other drawings according to these drawings without creating any inventive labor.

[0035] Figure 1 is a circuit module diagram of the electronic device of the first embodiment of the present application;

[0036] Figure 2 is a detailed circuit module diagram of the battery protection circuit of the first embodiment of the present application;

[0037] Figure 3a is Figure 2 is a circuit module diagram of the power-on detection module;

[0038] Figure 3b is Figure 2 is another circuit module diagram of the power-on detection module;

[0039] Figure 4 is a detailed circuit module diagram of the battery protection circuit of the second embodiment of the present application;

[0040] Figure 5 is a flow chart of the control method of the battery protection circuit of an embodiment of the present application. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0042] The terms “comprise” and “have” and any variations thereof that appear in the specification, claims and drawings of the present application are intended to cover not exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or modules is not limited to the listed steps or units, but can optionally include steps or units that are not listed, or can optionally include other steps or units inherent to the process, method, product or device. In addition, the terms “first”, “second” and “third” and the like are used to distinguish different objects, but not to describe a specific order. The connection of the present application includes direct connection and indirect connection, and indirect connection means that there can be other electronic components, pins and the like between the two connected components. The XX pin mentioned in the present application may or may not be an actual pin, for example, it may be only one pin of a component or one pin of a wire. The present application refers to and / or includes three cases, for example, A and / or B, including A, B, A and B.

[0043] First Embodiment

[0044] The embodiments of the present application provide an electronic device, for example, a mobile phone, a tablet computer, a notebook computer, a Bluetooth headset, an electronic toy, a wearable device, a mobile power supply, a drone, etc. Please refer to Figure 1, the electronic device includes a battery pack and a system circuit 300, the system circuit 300 includes a second authentication unit 310, the second authentication unit 310 is used for verifying whether the battery pack is an officially authenticated battery pack, the officially authenticated battery pack refers to a battery pack that is authenticated by the manufacturer of the electronic device. The system circuit 300 is connected with the battery pack, and the battery pack is used for powering the system circuit 300.

[0045] In the embodiment, the battery pack includes a battery 100 and a battery protection board ( Figure 1 The dashed area), the battery protection board includes a battery protection circuit 200, the battery protection circuit 200 is electrically connected with the positive and negative poles of the battery 100, the system circuit 300 is electrically connected with the battery protection circuit 200, the battery 100 powers the battery protection circuit 200, the battery protection circuit 200 protects the battery 100, for example, when the battery 100 is overcharged or overdischarged, because how the battery protection circuit 200 protects the battery 100 from overcharging and overdischarging is a common technical means in the art, which will not be repeated here. In the embodiment, the number of the battery 100 is one or more, preferably one, when it is multiple, the multiple batteries 100 can be connected in parallel, or connected in series, or connected in parallel and series. The battery 100 is preferably a lithium battery, and the capacity of the battery 100 is, for example, 1000mAH-15000mAH, such as 1000mAH, 0mAH, 0mAH, 4000mAH, 5000mAH, 6000mAH, 7000mAH, 8000mAH, 9000mAH, 10000mAH, 00mAH, 10mAH, 10mAH, 14000mAH, 15000mAH, etc. In the embodiment, the battery pack further includes a first resistor R1 and a first capacitor C1, the first resistor R1 and the first capacitor C1 are arranged for filtering, and the specific connection relationship is shown in Figure 1 . In addition, in other embodiments of the present application, the battery pack can further include other circuits or electronic elements. In addition, in other embodiments of the present application, the battery pack can not include the first resistor and the first capacitor.

[0046] In the embodiment, please refer to Figure 1 and Figure 2 , the battery protection circuit 200 includes a power supply end VDD, a power ground end GND, an abnormal protection unit 220, a main control unit 230, and a main switch unit 240.

[0047] In the embodiment, the power supply end VDD and the power ground end GND are used for corresponding electrical connection with the positive and negative poles of the battery 100, so that the battery 100 can power the battery protection circuit 200, and at the same time, the battery 100 forms a loop via the battery protection circuit 200 and the system circuit 300 to power the system circuit 300.

[0048] In the embodiment, the abnormality protection unit 220 is configured to control the battery 100 to stop charging or discharging when an abnormality of charging or discharging of the battery 100 is detected, so as to protect the battery 100. In the embodiment, the battery protection circuit 200 is configured to protect the battery 100 from overcharging, over-discharging, over-current charging / discharging and the like, so as to prevent permanent damage to the battery 100. In the embodiment, the abnormality protection unit 220 comprises an overcharging protection unit 221, an over-discharging protection unit 222 and an over-current protection unit (not shown in the figure). In other embodiments of the application, the abnormality protection unit 220 comprises one or two of the overcharging protection unit 221, the over-discharging protection unit 222 and the over-current protection unit.

[0049] The overcharging protection unit 221 is configured to protect the battery 100 from overvoltage during charging of the battery 100, for example, by stopping charging of the battery 100, so as to prevent damage or safety problems of the battery 100.

[0050] The over-discharging protection unit 222 is configured to protect the battery 100 from overvoltage during discharging of the battery 100, for example, by controlling the battery 100 to perform minimum discharging, generally stopping power supply to the system circuit 300, so as to prevent over-discharging of the battery 100 and permanent damage to the battery 100.

[0051] The over-current protection unit is configured to protect the battery 100 from over-current during discharging or charging of the battery 100, for example, by stopping discharging or charging of the battery 100, so as to prevent permanent damage or safety problems of the battery 100 caused by over-current.

[0052] In the embodiment, one end of the main switch unit 240 is connected with the negative electrode (as an example in the figure) or the positive electrode of the battery 100, the other end of the main switch unit 240 is connected with the system circuit 300 via the system terminal VM, the control end of the main switch unit 240 is connected with the main control unit 230, the main control unit 230 is connected with the abnormal protection unit 220, and the main control unit 230 controls the conduction or the turn-off of the main switch unit 240 to control the battery 100 to supply power to the system circuit 300 or stop supplying power to the system circuit 300. In the embodiment, the main switch unit 240 includes a switch tube and a substrate control circuit, the switch tube is a MOS tube, the control end of the switch tube is electrically connected with the main control unit 230, and the substrate control circuit is electrically connected with the main control unit 230, and the substrate control circuit is used to realize the correct biasing of the substrate of the switch tube. However, the application is not limited to this, and in other embodiments of the application, the main switch unit 240 can also include a charging switch and a discharging switch, the charging switch and the discharging switch are connected in series, the charging switch and the discharging switch are both MOS tubes, and the control end of the charging switch and the control end of the discharging switch are respectively electrically connected with the main control unit 230. In addition, in other embodiments of the application, the main switch unit 240 can also be other implementation forms, for example, only including a switch tube. In the embodiment, the main switch unit 240 is used to control the battery 100 to supply power to the system circuit 300, and specifically, a loop is formed by the battery 100, the system circuit 300 and the main switch unit 240 of the battery protection circuit 200 to supply power to the battery protection circuit 200. Specifically, the control end of the main switch unit 240 is electrically connected with the main control unit 230, one end of the main switch unit 240 is used to be electrically connected with the battery 100, for example, directly or indirectly connected with the negative electrode or the positive electrode of the battery 100, and the other end of the main switch unit 240 is electrically connected with the system circuit 300 via the system terminal VM, so that the battery 100, the system circuit 300 and the main switch unit 240 form a power supply loop, and the battery protection circuit 200 can control whether the battery 100 supplies power to the system circuit 300 by controlling the main switch unit 240.

[0053] In order to prevent the electronic device from replacing the battery pack without official authentication to cause a safety accident, in the embodiment, the battery protection circuit 200 further comprises a first authentication unit 252, the system circuit 300 comprises a second authentication unit 310, the first authentication unit 252 is in communication connection with the second authentication unit 310, the authentication modes of the first authentication unit 252 and the second authentication unit 310 are various, in the embodiment, the first authentication unit 252 stores a first encryption key and a second encryption key, the second authentication unit 310 also stores the first encryption key and the second encryption key, after the electronic device enters the authentication stage, the first authentication unit 252 generates a random number (a randomly generated number), and encrypts the random number by using the first encryption key, and sends the encrypted random number to the second authentication unit 310 of the system circuit 300, after receiving the encrypted random number, the second authentication unit 310 decrypts by using the first encryption key, then encrypts the decrypted random number by using the second encryption key and sends it to the first authentication unit 252, after receiving the encrypted random number, the first authentication unit 252 decrypts by using the second encryption key, compares the decrypted random number with the original random number, if they are the same, it means that the authentication is passed, it is a true battery pack, if they are not the same, it means that the authentication is not passed, it is a false battery pack. In addition, in other embodiments of the application, the authentication of the first authentication unit 252 and the second authentication unit 310 can also be realized by other authentication modes, for example, the first authentication unit 252 stores a first encryption key, the second authentication unit 310 also stores the first encryption key, which can also realize authentication; for another example, the first authentication unit 252 stores a second encryption key, the second authentication unit 310 also stores the second encryption key, which can also realize authentication. In the embodiment, when the first authentication unit 252 and the second authentication unit 310 do not pass the authentication, at this time the first authentication unit 252 outputs an authentication failure signal to the main control unit 230, the main control unit 230 controls the main control switch to be completely disconnected or partially disconnected, for example, the switch of the charging loop is disconnected, and the discharging loop remains conductive. In the embodiment, when the first authentication unit 252 and the second authentication unit 310 do not pass the authentication, at this time the first authentication unit 252 outputs an authentication failure signal to the main control unit 230, the main control unit 230 outputs a verification failure signal to the system circuit 300, and the system circuit 300 prompts.In addition, in other embodiments of the present application, the order of the first authentication unit 252 and the second authentication unit 310 can also be exchanged, that is, after the electronic device enters the authentication stage, the second authentication unit 310 of the system circuit 300 generates a random number (a randomly generated number), and encrypts the random number using the first encryption key, and sends the encrypted random number to the first authentication unit 252 of the battery protection circuit 200. After receiving the encrypted random number, the first authentication unit 252 decrypts it by the first encryption key, and then encrypts the decrypted random number by the second encryption key and sends it to the second authentication unit 310. After receiving the encrypted random number, the second authentication unit 310 decrypts it by the second encryption key, and compares the decrypted random number with the original random number. If they are the same, it means that the authentication is passed, and it is a true battery pack. If they are not the same, it means that the authentication is not passed, and it is a false battery pack. If it is a false battery pack, the system circuit 300 prompts at this time.

[0054] In order to prevent the battery protection board from being disassembled and assembled with a false battery 100 to form a battery pack, and the assembled battery pack can pass the above authentication, however, the electronic device will have security problems as easily as using a false battery 100, and will cause trouble to the user's use, and will also have an adverse effect on the brand of the electronic device. In the present embodiment, the battery protection circuit 200 further comprises a power-on detection module 210 and a tamper-proof storage unit 251. The power-on detection module 210 is connected to the power supply end VDD and the power ground end GND, respectively. The power-on detection module 210 is used to detect whether the battery protection circuit 200 is powered on, that is, the power-on detection module 210 is used to detect whether the power supply end VDD of the battery protection circuit 200 is connected to the positive electrode of the battery 100, and whether the power ground end GND of the battery protection circuit 200 is connected to the negative electrode of the battery 100. When the power supply end VDD is connected to the positive electrode of the battery 100 and the power ground end GND is connected to the negative electrode of the battery 100, the power-on detection module 210 confirms that the battery protection circuit 200 is powered on. In the present embodiment, the tamper-proof storage unit 251 does not store data by default, or stores non-first preset information. At this time, the first information stored in the tamper-proof storage unit 251 is NULL or other information other than the non-first preset information. When the battery protection circuit 200 is powered on for the first time, the first preset information is input to the tamper-proof storage unit 251 and stored. Thereafter, the first information stored in the tamper-proof storage unit 251 is the first preset information, and the first information in the tamper-proof storage unit 251 cannot be changed or the first preset information is stored again thereafter.

[0055] In the embodiment, the main control unit 230 is connected with the power-on detection module 210 and the anti-disassembly storage unit 251 respectively. When the power-on detection module 210 detects that the battery protection circuit 200 is powered on, the power-on detection module 210 outputs a power-on signal to the main control unit 230. The main control unit 230 reads the first information stored in the anti-disassembly storage unit 251, and compares the first information with the first preset information. If the main control unit 230 judges that the comparison result meets the first preset condition, the main control unit 230 outputs the battery 100 replacement information to the system circuit 300. The battery 100 replacement information is used to indicate that the battery 100 is replaced. At this time, it is indicated that the battery protection circuit 200 is not powered on for the first time, but for the second time or more. If the main control unit 230 judges that the comparison result does not meet the first preset condition, the main control unit 230 outputs the first preset information to the anti-disassembly storage unit 251. The anti-disassembly storage unit stores the first preset information as the first information. At this time, the power-on is for the first time, that is, the battery 100 is connected with the battery protection circuit 200 for the first time. In addition, in other embodiments of the application, the battery 100 replacement information is not limited to being output to the system circuit 300, but can also be output to other units of the battery protection circuit 200, and can also be output to a remote server.

[0056] In the embodiment, the first preset condition is that the first information is the same as the first preset information. For example, the first preset information is a number, a character, etc. The first preset information is, for example, non-empty information such as 10, "a", "A", "0xAA", etc.

[0057] Please refer to Figure 2 、 Figure 3a 、 Figure 3b In the embodiment, the power-on detection module 210 includes a charging unit and a threshold judgment unit 212. The first end of the charging unit is connected with the power supply end VDD, the second end of the charging unit is connected with the power ground end GND, the third end of the charging unit is connected with the input end of the threshold judgment unit 212, and the output end of the threshold judgment unit 212 is connected with the main control unit 230.

[0058] In the embodiment, the threshold judgment unit 212 outputs a first level signal when the input voltage thereof meets a first condition, and the signal output by the threshold judgment unit 212 changes from the first level signal to a second level signal when the input voltage thereof meets a second condition. Correspondingly, the power-on signal is the second level signal or the edge signal changing from the first level signal to the second level signal, and is preferably the edge signal, for example, a rising edge signal or a falling edge signal.

[0059] In the embodiment, the threshold judging unit 212 can detect the size of the input voltage in real time, and determine the output signal according to the size of the input voltage. For example, when the battery protection circuit 200 is connected with the battery 100, the charging unit is charged. In the first stage of charging the charging unit, the input voltage of the threshold judging unit 212 satisfies the first condition, at this time, the threshold judging unit 212 outputs the first level signal. With the charging unit continuing to be charged, the input voltage of the threshold judging unit 212 satisfies the second condition (the time length from starting charging to satisfying the second condition is the first preset time length), the charging unit enters the second stage of being charged, that is, when the input voltage of the threshold judging unit 212 reaches the first voltage threshold, the signal output by the threshold judging unit 212 changes from the first level signal to the second level signal.

[0060] Optionally, as shown in Figure 3a , Figure 3b , the charging unit can include the charging element 211 and the second capacitor C2, wherein the charging element 211 can be a resistor, a depletion mode switch tube, a current source or a capacitor. In actual application, when the positions of the charging element 211 and the second capacitor C2 are different, the change trend of the input voltage of the threshold judging unit 212 is different, which is explained and described below. Figure 3a , Figure 3b

[0061] As an example, as shown in Figure 3a , the first end of the charging element 211 is connected with the power supply end VDD, the second end of the charging element 211 and the first end of the second capacitor C2 are connected, and the connection point of the charging element 211 and the second capacitor C2 is connected with the input end of the threshold judging unit 212, and the second end of the second capacitor C2 is connected with the power ground end GND.

[0062] In the embodiment of the application, the charging element 211 is connected between the power supply end VDD and the second capacitor C2. When the battery protection circuit 200 starts to be connected with the battery 100, the battery 100 can charge the second capacitor C2 through the power supply end VDD and the charging element 211, so as to gradually increase the input voltage of the threshold judging unit 212. That is, the charging element 211 can be turned on when there is a voltage difference between the two ends, so as to charge the second capacitor C2. Thus, in the example, the threshold judging unit 212 outputs the first level signal when the input voltage is less than the first voltage threshold, and the signal output by the threshold judging unit 212 changes from the first level signal to the second level signal when the input voltage reaches the first voltage threshold.

[0063] As another example, as shown in Figure 3b ​As shown, the first terminal of the second capacitor C2 is connected to the power supply terminal VDD, the second terminal of the second capacitor C2 is connected to the first terminal of the charging element 211, and the connecting point of the second capacitor C2 and the charging element 211 is connected to the input terminal of the threshold judging unit 212, and the second terminal of the charging element 211 is connected to the power ground terminal GND.

[0064] In the embodiment of the present application, the charging element 211 is connected between the second capacitor C2 and the power ground terminal GND. When the battery protection circuit 200 is just connected to the battery 100, the voltage between the two electrode plates of the second capacitor C2 is equal, the voltage drop is 0, and the input voltage of the threshold judging unit 212 is approximately equal to the voltage of the battery 100. Thereafter, the battery 100 gradually charges the second capacitor C2, and the voltage drop between the two electrode plates of the second capacitor C2 becomes larger and larger. Since the input voltage of the threshold judging unit 212 is equal to the voltage of the battery 100 minus the voltage drop of the second capacitor C2, the input voltage of the threshold judging unit 212 gradually becomes smaller. Thus, the threshold judging unit 212 outputs the first level signal when the input voltage thereof is greater than the first voltage threshold, and outputs the second level signal when the input voltage thereof drops to less than or equal to the first voltage threshold.

[0065] In the embodiment, the first voltage threshold is the threshold voltage of the threshold judging unit 212, which can be a set voltage value, and the embodiment does not limit the specific value of the first voltage threshold. Illustratively, the charging element 211 can be implemented by a resistor, a depletion mode switch tube or a current source, and the specific connection manner is a routine technique in the art, which is not described herein. It can be understood that the charging element 211 can also be implemented by other elements, as long as it can satisfy the above-mentioned electric signal transmission principle, and the embodiment does not limit it. In the embodiment, the threshold judging unit 212 can be an inverter with threshold, for example, a Schmitt trigger. In addition, in other embodiments of the present application, the threshold judging unit 212 can be other conventional voltage comparators.

[0066] Figure 3a 、 Figure 3bThe provided scheme is not to output the power-on signal immediately when the battery protection circuit 200 is connected to the battery 100, but to output the power-on signal after a period of stable connection (the time required to charge to the first voltage threshold, that is, the first preset time length). This processing is beneficial to prevent the power-on detection module 210 from misjudging the power-on, and can especially improve the anti-interference capability. The period of time can be 5 minutes, 10 minutes, 30 minutes, 60 minutes, 120 minutes, etc., and can be set as needed. In addition, in other embodiments of the present application, the power-on signal can also be output without a delay period, that is, the power-on signal is output as soon as the battery 100 is connected to the battery protection circuit 200. This scheme has weaker anti-interference capability. In addition, in other embodiments of the present application, the power-on signal can also be output after the battery 100 is continuously connected to the battery protection circuit 200 for a period of time through other ways.

[0067] In addition, the power-on detection module 210 of the present application is not limited to the above-mentioned circuit, but can also be other conventional power-on detection modules 210, which will not be described here.

[0068] In the present embodiment, the anti-disassembly storage unit 251 is a non-volatile memory (NVM) that can still save data after power failure. In the present embodiment, the anti-disassembly storage unit 251 includes a read-only memory (ROM), such as a programmable read-only memory (PROM), a one-time programmable memory (OTP), or other read-only memories. This type of memory cannot be changed after the first preset information is written at power-on, and has good security and reliability. In addition, in other embodiments of the present application, the anti-disassembly storage unit 251 can also be a flash memory, a magnetic storage, or other erasable and programmable non-volatile memories. This type of memory can be erased and re-input with non-first preset information, and has better flexibility than the read-only memory, but the security is not as good.

[0069] The battery protection circuit 200 of the embodiment comprises a power-on detection module 210 and an anti-disassembly storage unit 251. When the power-on detection module 210 detects power-on of the battery protection circuit 200, it outputs a power-on signal to a main control unit 230. The main control unit 230 reads first information stored in the anti-disassembly storage unit 251, compares the first information with first preset information, and outputs battery 100 replacement information if the comparison result meets first preset conditions. The battery 100 replacement information is used to indicate that the battery 100 is replaced. If the comparison result does not meet the first preset conditions, the main control unit 230 outputs the first preset information to the anti-disassembly storage unit 251, and the anti-disassembly storage unit 251 stores the first preset information as the first information. Through such processing, when the battery protection circuit 200 is powered on for the first time, the first information stored in the anti-disassembly storage unit 251 is empty (NULL) or is not the first preset information. The main control unit 230 determines that the comparison result does not meet the first preset conditions, indicating that the battery 100 and the battery protection board are assembled together for the first time to form a battery pack at the factory end, and the main control unit 230 outputs the first preset information to the anti-disassembly storage unit 251. The anti-disassembly storage unit 251 stores the first preset information as the first information. When the battery protection board is disassembled from the original battery 100, the battery protection circuit 200 on the battery protection board will be powered off. When the battery protection circuit 200 is powered on again, it is powered on for the second time or more. At this time, it is very likely that the original battery 100 is replaced with a poor-quality battery 100. At this time, the first information stored in the anti-disassembly storage unit 251 is the first preset information (stored for the first time), and the main control unit 230 determines that the comparison result meets the first preset conditions, indicating that the battery 100 and the battery protection board are not assembled for the first time at the factory end, and it is very likely that the original battery 100 is replaced with a poor-quality battery 100. At this time, the main control unit 230 outputs the battery 100 replacement information. Through the battery 100 replacement information, the user can know that the battery 100 may be replaced / stolen with a poor-quality battery 100, preventing the battery 100 of the electronic device from being maliciously replaced, improving the safety of the user using the electronic device, reducing the probability of safety accidents of the battery 100, and reducing the user's confusion. Moreover, through the battery 100 replacement information, the factory end can also know that the battery 100 may be replaced, which is convenient for subsequent maintenance of the electronic device by the manufacturer and can also prevent damage to their own brand.

[0070] In the embodiment, when the authentication stage is completed, the first authentication unit 252 or the second authentication unit 310 judges the true battery pack, and the first authentication unit 252 or the second authentication unit 310 outputs a signal of passing the authentication to the main control unit 230, and the main control unit 230 further verifies whether the battery 100 is replaced; if the first authentication unit 252 or the second authentication unit 310 outputs a signal of failing the authentication to the main control unit 230, it indicates that the battery pack is an unauthenticated battery pack, and it is not necessary to verify whether the battery 100 is replaced.

[0071] Please continue to see Figure 1 、 Figure 2 In the embodiment, the battery 100 replacement information is output to the system circuit 300, the system circuit 300 comprises a first indicating element, for example, an indicating lamp, a display screen, a digital tube, a buzzer, etc., and the first indicating element is connected with the main control unit 230 of the battery protection circuit 200; when the first indicating element receives the battery 100 replacement information, the first indicating element indicates, for example, the indication of the battery 100 being replaced on the display screen, which is convenient for the user to know. In the embodiment, the battery protection circuit 200 is connected with a second indicating element (not shown in the figure), and the second indicating element is also connected with the main control unit 230; the second indicating element is, for example, an indicating lamp, a display screen, a digital tube, a buzzer, etc., and when the second indicating element receives the battery 100 replacement information, the second indicating element indicates, which is convenient for the user to know. In the embodiment, the battery protection circuit 200 is further connected with a sending device, for example, a wireless sending device or a wired sending device, and the sending device is used to connect with a remote server, for example, a server located in the factory of the manufacturer; when the main control unit 230 outputs the battery 100 replacement information, the battery 100 replacement information and the unique code information of the electronic device are output to the server through the sending device, and the server knows which electronic device has the battery 100 possibly replaced. In addition, in other embodiments of the present application, the first indicating element, the second indicating element and the sending device can have one or two of them. In addition, in other embodiments of the present application, the battery 100 replacement information can also be used to control the main switch unit 240, for example, to control the disconnection of the discharge circuit, so as to prevent the safety problem caused by the discharge of the battery 100.

[0072] Please continue to see Figure 1In the embodiment, the battery protection circuit 200 comprises a first communication terminal TX1, the system circuit 300 comprises a second communication terminal TX2, the first communication terminal TX1 is connected with the second communication terminal TX2, the battery 100 replacement information and the encrypted random number are output to the system circuit 300 via the first communication terminal TX1 and the second communication terminal TX2, and the decrypted and re-encrypted random number is output to the battery protection circuit 200 via the second communication terminal TX2 and the first communication terminal TX1.

[0073] In the embodiment, the battery protection circuit 200 is made on the same semiconductor substrate, that is, on the same chip, at this time, the power supply terminal VDD is a power supply pin, the power ground terminal GND is a power ground pin, and the first communication terminal TX1 is a first communication pin. However, the application is not limited to this, in other embodiments of the application, the elements of the battery protection circuit 200 except the main switch unit 240 are located on the first integrated circuit chip, and the main switch unit 240 is located on the second integrated circuit chip, that is, the first integrated circuit chip is made on one semiconductor substrate, and the second integrated circuit chip is made on another semiconductor substrate, at this time, the first integrated circuit chip and the second integrated circuit chip are packaged into one product. In addition, in other embodiments of the application, the elements of the battery protection circuit 200 except the first authentication unit 252 are located on the first integrated circuit chip, and the first authentication unit 252 is located on the third integrated circuit chip. In addition, in other embodiments of the application, the elements of the battery protection circuit 200 except the first authentication unit 252 and the main switch unit 240 are located on the first integrated circuit chip, and the first authentication unit 252 and the main switch unit 240 are located on the fourth integrated circuit chip or on two independent chips.

[0074] In the factory assembly process or in the daily use process of the user, there may be some scenarios: after the battery 100 and the battery protection board are installed together, that is, after the battery protection circuit 200 is powered on for a period of time, the battery 100 and the battery protection board may need to be disconnected or the battery 100 and the battery protection board are disconnected, for example, the battery 100 and the battery protection board are installed incorrectly due to specifications, or the battery 100 and the battery protection board are not connected firmly and are automatically disconnected after being used for a period of time, are firmly connected after being repaired, or the battery protection board and the battery 100 of the assembled battery pack are disconnected due to the mistake of the factory or the user, or the battery protection board is powered off due to the depletion of the battery 100, etc. At this time, after the battery 100 and the battery protection board are normally connected and powered on again, the actual battery 100 is still the original battery 100, but according to the previous description, the battery protection circuit 200 will judge that it is not the first power-on, will output the battery 100 replacement information, and will cause false indication, which is not expected. In order to solve the problem, the application provides a second embodiment.

[0075] Second embodiment

[0076] Please refer to Figure 4 , Figure 4 is a partial circuit module diagram of the battery protection circuit 200 of the second embodiment of the present application, the present embodiment is similar to the first embodiment, therefore the parts not described in the present embodiment can refer to the first embodiment, the main difference between the present embodiment and the first embodiment is that the battery protection circuit 200 is improved.

[0077] Please refer to Figure 1 and Figure 4 In the present embodiment, the battery protection circuit 200 further comprises a battery information acquisition unit 261 and a battery information storage unit 262, the battery information acquisition unit 261 is used to obtain the information of the voltage of the battery 100 and the current flowing through the main switch unit 240 in real time or at regular intervals, this information is the battery 100 sampling information, the main control unit 230 is connected with the battery information acquisition unit 261 and the battery information storage unit 262 respectively, the main control unit 230 of the present embodiment has the functions of calculation, operation, etc., the main control unit 230 obtains the battery 100 sampling information at regular intervals or in real time, and performs calculation and evaluation according to the obtained battery 100 sampling information, so as to obtain the battery information, or directly obtains the battery information (such as the current battery voltage), the battery information includes the number of charge / discharge times, the charge / discharge rate, the power consumption law, the remaining battery capacity, the battery attenuation degree, the current battery voltage, the battery resistance size and other indicators of the battery 100, the main control unit 230 outputs the battery information to the battery information storage unit 262 in real time or at regular intervals, the battery information storage unit 262 stores the battery information, the battery information storage unit 262 is a non-volatile memory, even if the battery protection circuit 200 is powered off, the battery information storage unit 262 can also retain the battery information stored last time. In the present embodiment, the battery information storage unit 262 and the anti-disassembly storage unit 251 are two different storage elements, but the present application is not limited to this, in other embodiments of the present application, the battery information storage unit 262 and the anti-disassembly storage unit 251 are the same storage element, but they are stored in different storage addresses.

[0078] In the embodiment, after receiving the power-on signal, the main control unit 230 compares the first information with the first preset information. If the comparison result meets the first preset condition, the main control unit 230 further obtains the current battery 100 sampling information via the battery information acquisition unit 261. The main control unit 230 obtains the current battery information based on the current battery 100 sampling information. The main control unit 230 reads the battery information stored in the battery information storage unit 262 (at this time, the stored information is still the battery information stored before power-off). The main control unit 230 compares the current battery information with the battery information stored before power-off. If the comparison result meets the second preset condition, the main control unit 230 outputs the battery 100 replacement information. At this time, it indicates that the current information of the battery 100 is greatly different from the battery information stored before power-off, which means that the battery 100 has been replaced. If the comparison result does not meet the second preset condition, it indicates that the current information of the battery 100 is less different from the battery information stored before power-off, which means that the battery 100 has not been replaced. At this time, even if the first preset condition is met, the main control unit 230 does not output the battery 100 replacement information.

[0079] In the embodiment, the second preset condition is that the difference between the current battery information and the stored battery information is greater than or equal to a preset value, which is for example a preset percentage, such as 10%, 8%, 5%, etc. For example, the battery information is the battery 100 attenuation degree of the battery 100. When the battery protection circuit 200 is not powered on for the first time, the main control unit 230 determines that the comparison result meets the first preset condition. The battery protection circuit 200 further obtains the current battery 100 attenuation degree through calculation. For example, the current battery 100 attenuation degree is 1%, and the main control unit 230 reads the battery 100 attenuation degree of 12% from the battery information storage unit 262. The difference between them is 11%, which is relatively large. The main control unit 230 considers that the comparison result meets the second preset condition. For another example, the battery information is the battery voltage. When the battery protection circuit 200 is not powered on for the first time, the main control unit 230 determines that the comparison result meets the first preset condition. The battery protection circuit 200 further obtains the current battery voltage. For example, the current battery voltage is 2V (after voltage division), and the main control unit 230 reads the battery voltage of 2.05V from the battery information storage unit 262. The voltage difference between them is 0.05V, and the difference percentage is about 2.5%. The difference between them is relatively small. The main control unit 230 considers that the comparison result does not meet the second preset condition. In addition, in other embodiments of the present application, the preset value is not limited to the preset percentage, but can also be a preset numerical value, etc.

[0080] In the embodiment, the battery information acquisition unit 261 is used to obtain the information of the voltage of the battery 100 and the current flowing through the main switch unit 240, which is a conventional technique in the art, and the specific details are not described herein, for example, by connecting with the power supply end VDD to obtain the information of the voltage of the battery 100, by connecting with both sides of the main switch unit 240 to obtain the information of the current flowing through the main switch unit 240, or by connecting with both ends of a sampling resistor connected in series with the main switch unit 240 to obtain the information of the current flowing through the main switch unit 240.

[0081] When the battery protection circuit 200 of the embodiment is powered on, the main control unit 230 compares the first information with the first preset information, and if the comparison result meets the first preset condition, the main control unit 230 does not immediately output the battery 100 replacement information, so that the problem of false indication does not occur. The main control unit 230 further obtains the current battery information through the battery information acquisition unit 261 and reads the battery information stored in the battery information storage unit 262. The main control unit 230 compares the current battery information with the read battery information, and if the comparison result meets the second preset condition, it indicates that the battery 100 has been replaced, and the main control unit 230 outputs the battery 100 replacement information. Through such processing, the problem of false indication caused by the battery 100 being powered off for a short time and then immediately powered on can be further prevented, the use of the battery 100 can be further reduced, and the cost can be reduced.

[0082] Based on the above embodiment, the application further provides a corresponding control method, which is described in detail in combination with Figure 1 、 Figure 2 and Figure 5 . The embodiment of the application provides a control method of the battery protection circuit 200, which comprises the following steps:

[0083] S110: obtaining a power-on signal;

[0084] S120: reading the first information in the anti-disassembly storage unit 251;

[0085] S130: comparing the first information with the first preset information;

[0086] S141: if the comparison result meets the first preset condition, outputting the battery 100 replacement information;

[0087] S142: if the comparison result does not meet the first preset condition, outputting the first preset information to the anti-disassembly storage unit 251, and the anti-disassembly storage unit 251 stores the first preset information as the first information.

[0088] The above method of the embodiment can be understood in combination with the foregoing description, and will not be described herein.

[0089] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above functional units and modules is taken as an example, and in actual application, the above functions can be completed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit, and the integrated unit can be realized in the form of hardware or in the form of software functional unit. In addition, the specific names of each functional unit and module are only for easy distinction, and do not limit the protection scope of the application. The specific working process of the units and modules in the system can refer to the corresponding process in the foregoing method embodiments, which will not be repeated here.

[0090] It should be understood that "a plurality of" as referred to herein means two or more. Other embodiments of the application will be apparent to those of ordinary skill in the art having the benefit of this disclosure upon consideration of the specification and practice of the application disclosed herein. The application is intended to cover any variations, uses or adaptations of the application including equivalents thereof following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice in the art to which the application pertains. The specification and examples are to be construed as merely illustrative of the present application and not limitative of the true scope and spirit of the application, which is measured by the claims.

[0091] It should be noted that each of the embodiments in the specification adopts a progressive description manner, and each embodiment focuses on the difference from other embodiments. The same and similar parts between embodiments can be referred to each other. For the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the part of the method embodiment.

[0092] The above disclosure is only the preferred embodiment of the application, and of course cannot limit the scope of the application, so the equivalent changes made according to the claims of the application still fall within the scope of the application.

Claims

1. A battery protection circuit for use in an electronic device, said battery protection circuit being contained in a battery protection board, said battery protection board being assembled with a battery to form a battery pack, said battery pack being connected with a system circuit to form an electronic device, wherein, The battery protection circuit comprises a power supply end, a power ground end, an overcharge protection unit, an overdischarge protection unit, a main control unit, and a main switch unit, wherein the power supply end and the power ground end are used to be connected with a battery, a control end of the main switch unit is electrically connected with the main control unit, one end of the main switch unit is used to be electrically connected with the power supply end or the power ground end, and the other end of the main switch unit is used to be electrically connected with a system circuit, and the main switch unit is used to control the battery to supply power to the system circuit. The battery protection circuit further comprises a power-on detection module and an anti-disassembly storage unit, the power-on detection module is connected with the power supply end and the power ground end respectively, the power-on detection module is used to detect whether the battery protection circuit is powered on, the main control unit is connected with the power-on detection module and the anti-disassembly storage unit respectively, when the power-on detection module detects that the battery protection circuit is powered on, the power-on detection module outputs a power-on signal to the main control unit, the main control unit reads first information stored in the anti-disassembly storage unit, and compares the first information with first preset information, if a comparison result meets a first preset condition, the main control unit outputs battery replacement information, the battery replacement information is used to indicate that the battery is not powered on for the first time, power-on refers to electrical connection between the battery and the battery protection board, if the comparison result does not meet the first preset condition, the main control unit outputs the first preset information to the anti-disassembly storage unit, and the anti-disassembly storage unit stores the first preset information as the first information. The battery protection circuit comprises a first authentication unit, and the first authentication unit is used to communicate with a second authentication unit of the system circuit to verify whether the battery protection board is an original battery protection board. After receiving a signal of passing authentication, verification of whether the battery is replaced is performed. The first preset condition comprises that the first information is the same as the first preset information.

2. The battery protection circuit of claim 1, wherein, The battery protection circuit further comprises a battery information storage unit and a battery information acquisition unit, the battery information acquisition unit and the battery information storage unit are connected with the main control unit, and the battery information storage unit is used to store battery information before power-off.

3. The battery protection circuit of claim 1, wherein, If the comparison result meets the first preset condition, the main control unit obtains current battery information via the battery information acquisition unit, compares the current battery information with battery information stored in the battery information storage unit, and outputs battery replacement information if a comparison result meets a second preset condition. The second preset condition is that a difference between the current battery information and the stored battery information is greater than or equal to a preset value.

4. The battery protection circuit of claim 3, wherein, When the power-on detection module detects that a time length during which the power-on detection module is connected with the battery is greater than or equal to a first preset time length, the power-on detection module outputs a power-on signal to the main control unit.

5. The battery protection circuit of claim 1, wherein, The battery protection circuit is located on the same chip; or 6. The battery protection circuit of claim 1, wherein, Elements of the battery protection circuit except the main switch unit are located on one chip, and the main switch unit is located on another chip. Or Elements of the battery protection circuit except the first authentication unit are located on one chip; or Elements of the battery protection circuit except the main switch unit and the first authentication unit are located on one chip; or ​ The battery protection circuit verifies whether the battery is replaced after verifying that the battery is an original battery.

7. A battery protection plate characterized by, The battery protection circuit comprises: a printed circuit board; The battery protection circuit according to any one of claims 1-6 is mounted on the printed circuit board.

8. A battery pack, characterized by, The battery protection circuit comprises: a battery; The battery protection circuit according to any one of claims 1-6 or the battery protection board according to claim 7, wherein a power supply end of the battery protection circuit is connected to a positive pole of the battery, and a power supply ground end of the battery protection circuit is connected to a negative pole of the battery.

9. An electronic device, comprising: The battery protection circuit comprises: a system circuit; The battery protection circuit according to any one of claims 1-6 or the battery protection board according to claim 7 or the battery pack according to claim 8, wherein the system circuit is connected to the battery via the battery protection circuit.

10. A control method of a battery protection circuit, applied to an electronic device, the battery protection circuit being included in a battery protection board, the battery protection board being assembled with a battery to form a battery pack, the battery pack being connected with a system circuit to constitute the electronic device, characterized in that, The battery protection circuit comprises: authentication of the authenticity of the battery protection board, wherein the battery protection circuit comprises a first authentication unit configured to communicate with a second authentication unit of a system circuit to verify whether the battery protection board is an original battery protection board; output of a signal indicating that the authentication is passed or a signal indicating that the authentication is not passed; acquisition of a power-on signal, wherein the power-on refers to electrical connection of the battery to the battery protection board; reading of stored first information, wherein the first information is stored in the battery protection circuit; comparison of the first information with first preset information after the signal indicating that the authentication is passed is obtained; if the comparison result meets a first preset condition, output of battery replacement information, wherein the battery replacement information is used to indicate that the battery is replaced; if the comparison result does not meet the first preset condition, output of the first preset information and storage of the first preset information as the first information.

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