Battery protection control circuit and method and electronic equipment

Abstract

The invention provides a battery protection control circuit and method and electronic equipment, and the circuit comprises a battery cell, a comparator, a voltameter, a control chip, and a switching circuit. The positive electrode of the battery cell is coupled to the in-phase input end of the comparator; the inverting input end of the comparator is coupled with the charging forbidding voltage; the cathode of the battery cell is connected with reference ground; the output end of the comparator is coupled with the input end of the voltameter; the output end of the voltameter is coupled to the input end of the control chip, the first end of the switching circuit is coupled to the positive electrode of the battery cell, the second end of the switching circuit is coupled to external equipment, and the third end of the switching circuit is coupled to the output end of the control chip; wherein the control chip obtains the state information of the voltameter, and under the condition that the state information of the voltameter is a first state, the control chip controls the switching circuit to be switched off, so that the external equipment is forbidden to charge the battery cell.

Description

Technical Field

[0001] This application belongs to the field of energy storage, specifically relating to a battery protection control circuit, method, and electronic device. Background Technology

[0002] A battery protection control circuit is a circuit used to monitor, control, and protect a battery. Its main function is to ensure that the battery is in a safe operating state during charging and discharging. For devices that use batteries, prolonged storage can cause the battery to be over-discharged to extremely low voltage, resulting in irreversible chemical reactions inside the battery, posing a safety risk if it continues to be used. Therefore, how to prevent battery failure when it is left idle for a long time or in an over-discharged state is a technical problem that urgently needs to be solved. Summary of the Invention

[0003] The purpose of this application is to provide a battery protection control circuit, method, and electronic device that can automatically protect the energy storage battery when the battery voltage is too low at a lower cost and improve control flexibility.

[0004] In a first aspect, embodiments of this application provide a battery protection control circuit, including: a battery cell, a comparator, a fuel gauge, a control chip, and a switching circuit; the positive terminal of the battery cell is coupled to the non-inverting input terminal of the comparator; the inverting input terminal of the comparator is coupled to a charge-disable voltage; the negative terminal of the battery cell is connected to a reference ground; the output terminal of the comparator is coupled to the input terminal of the fuel gauge; the output terminal of the fuel gauge is coupled to the input terminal of the control chip; a first terminal of the switching circuit is coupled to the positive terminal of the battery cell; a second terminal of the switching circuit is coupled to an external device; and a third terminal of the switching circuit is coupled to the output terminal of the control chip; wherein, the control chip acquires the status information of the fuel gauge, and when the status information of the fuel gauge is in a first state, the control chip controls the switching circuit to disconnect, so as to prevent the external device from charging the battery cell.

[0005] Secondly, embodiments of this application provide a battery protection control method for the battery protection control circuit in any of the above embodiments, comprising: inputting the output voltage of the battery cell to the non-inverting input terminal of a comparator, and inputting the charging disable voltage to the inverting input terminal of the comparator to obtain the state information of the fuel gauge; acquiring the state information of the fuel gauge through a control chip; and, when the state information of the fuel gauge is in a first state, controlling the switching circuit to disconnect through the control chip to prevent external devices from charging the battery cell.

[0006] Thirdly, embodiments of this application provide an electronic device that includes the battery protection control circuit of the first aspect of this application.

[0007] In this embodiment, a combination of hardware and software is used. The output voltage of the battery cell is input to the non-inverting input of the comparator, and the charging-restricted voltage is input to the inverting input of the comparator to obtain the state information of the fuel gauge. The state information of the fuel gauge reflects whether the output voltage of the battery cell is lower than the charging-restricted voltage. If the battery cell is in normal use, its output voltage is higher than the charging-restricted voltage, and the state information of the fuel gauge is in the second state. If the battery cell is over-discharged to an extremely low voltage, or has been disassembled and used to counterfeit genuine batteries, the output voltage is not higher than the charging-restricted voltage, and the state information of the fuel gauge is in the first state. The state information of the fuel gauge is obtained by the control chip. When the state information of the fuel gauge is in the first state, the control chip controls the switching circuit to disconnect, thereby preventing external devices from charging the battery cell. By using a comparator to detect whether the cell's output voltage is lower than the charging prohibition voltage, and controlling the switching circuit's on and off via a control chip, this approach avoids the high cost of implementing 0V charging prohibition through a hardware protection IC, which requires integrating an additional 0V charging prohibition hardware circuit on top of over-discharge protection, and also avoids the high cost of adding a control unit and corresponding voltage sampling circuit at the battery end when implementing 0V charging prohibition through software programming. This allows for a lower cost and higher flexibility in preventing charging in cases of over-discharge to extremely low voltage or battery hard failure, thus improving the safety of energy storage batteries.

[0008] Additional aspects and advantages of the technical solutions of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description

[0009] Figure 1 A schematic diagram of the implementation framework of a battery protection control circuit according to an embodiment of this application is shown;

[0010] Figure 2 A schematic diagram of the logic flow of an implementation scheme in a battery protection control circuit according to an embodiment of this application is shown.

[0011] Figure 3 A schematic diagram of the composition of a battery protection control circuit according to an embodiment of this application is shown;

[0012] Figure 4 One of the schematic flowcharts of a battery protection control method according to an embodiment of this application is shown;

[0013] Figure 5 A second schematic flowchart of a battery protection control method according to an embodiment of this application is shown;

[0014] Figure 6 A third schematic flowchart of a battery protection control method according to an embodiment of this application is shown;

[0015] Figure 7 A schematic diagram of the composition of an electronic device according to an embodiment of this application is shown;

[0016] Component markings:

[0017] Vcell battery cell, U1 comparator, U2 fuel gauge, U4 control chip, R1 first resistor, R2 second resistor, R3 third resistor, U3 path management chip, Q1 first MOSFET, Q2 second MOSFET, 102 switch circuit, 20 external devices, 10 electronic devices, 100 battery protection control circuit, V1 non-inverting input, V2 inverting input, VDD2 fuel gauge input, SWI1 fuel gauge output, SWI2 control chip input, SWI3 control chip output, VREG feedback voltage, VDD1 comparator operating voltage, VSS comparator ground reference, VBAT path management chip input, DSG path management chip first output, CHG path management chip second output, GND1 fuel gauge ground, GND2 control chip ground, GND3 path management chip ground, SWI4 path management chip third terminal, VBUS path management chip second terminal, VOUT comparator output. Detailed Implementation

[0018] To better understand the above-mentioned objectives, features, and advantages of the embodiments of this application, the embodiments of this application will be further described in detail below with reference to the accompanying drawings and specific implementation methods. It should be noted that, unless otherwise specified, the embodiments of this application and the features within them can be combined with each other.

[0019] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, embodiments of this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0020] Figure 1 This illustrates a basic framework for an implementation of the battery protection control circuit 100 of this application.

[0021] In related technologies, battery protection control circuits typically include:

[0022] Battery cell: The battery cell is the core component of a battery that supplies power to an external load. It is used to store electrical energy and discharge it to the external load, as well as to supply power to the fuel gauge in the battery protection control circuit 100.

[0023] The battery protection circuit is an integrated circuit used in the battery protection control circuit 100 to protect the battery from damage caused by overcharging, over-discharging, or internal circuit problems.

[0024] The protection MOSFET is a metal oxide semiconductor (MOS) used in the battery protection control circuit 100 as a controlled device to protect the battery during the charging and discharging process.

[0025] A path management chip is an integrated circuit used in the battery protection control circuit 100 to manage the electrical energy path for charging and discharging.

[0026] The control unit, also known as the MCU, can communicate with the fuel gauge in the battery protection control circuit 100 and send and receive data. Based on the data, it can control the path management IC to prevent charging.

[0027] In addition to the aforementioned technologies, this application also includes a control circuit. This control circuit controls the power supply to the fuel gauge by acquiring the voltage of the battery cell. For example, when the control circuit detects that the acquired voltage of the battery cell is lower than a preset charging threshold, it can stop supplying power to the fuel gauge, thereby powering off the fuel gauge, disconnecting the power supply path, and thus blocking the battery cell from supplying power to the outside world.

[0028] It should be understood that the charging prohibition mentioned in this application refers to a state of the electronic device in which the energy storage battery cannot be charged even if the charger is correctly plugged in to power the electronic device, or if the electronic device is powered by other possible power supply methods.

[0029] Figure 2 A schematic diagram of the execution scheme of the battery protection control circuit 100 provided in this application is shown.

[0030] The execution logic of the battery protection control circuit 100 provided in this application is mainly divided into two parts: hardware logic and software logic. Regarding the hardware, it should be understood that the battery protection control circuit 100 is located within the Battery Management System (BMS) that is integrated with the energy storage battery. Since the BMS is integrated with the energy storage battery, even if the energy storage battery is placed on a charger, the charging path controlled by the battery protection control circuit 100 to charge the cells in the energy storage battery remains disconnected, and the cells cannot be charged, even if the energy storage battery is placed on a charger.

[0031] Figure 2 The detection of cell voltage and the determination of whether the cell voltage is below the charging prohibition threshold are performed by... Figure 1The control circuit executes this. It receives the cell voltage and compares it to the charging lockout voltage. If the cell voltage is greater than the charging lockout voltage, the control circuit outputs a high level. If the cell voltage is less than or equal to the charging lockout voltage, the control circuit outputs a low level.

[0032] Figure 2 The setting of the flag position to 0 or 1 is determined by... Figure 1 The fuel gauge operates on this principle. When the fuel gauge receives a high level from the control circuit, it sets its internal flag to 1. When it receives a low level from the control circuit, it sets its internal flag to 0.

[0033] Figure 1 When the control chip in the device senses that the charger is plugged in, it attempts to read the value of a flag bit in the fuel gauge. When the value of this flag bit is 1, it controls the charging path for charging the battery cell to close, allowing the charger to supply power to this electronic device. When the value of this flag bit is 0, it controls the charging path for charging the battery cell to open, preventing the charger from supplying power to this electronic device.

[0034] In other words, in this application, the battery cell voltage is detected at the hardware level. After the battery cell voltage is compared with the 0V charging-prohibited power supply, the flag bit of the fuel gauge is determined. Then, the updated flag bit is read at the software level, and corresponding logical judgments and executions are performed based on the value of the flag bit. Finally, the charging-prohibited function is realized through the battery protection control circuit 100.

[0035] Figure 1 The path management chip plays a role in over-discharge protection when the voltage of cell Vcell is less than or equal to the over-discharge protection voltage UVP of cell Vcell. This will be described in detail later. Figure 1 The battery protection circuit and protection MOSFET are part of the BMS's routine battery protection functions. Figure 2 Not yet covered.

[0036] In one embodiment of this application, a battery protection control circuit 100 is provided, such as... Figure 3 As shown, the battery protection control circuit 100 of this embodiment includes: a battery cell Vcell, a comparator U1, a fuel gauge U2, a control chip U4, and a switching circuit 102; the positive terminal of the battery cell Vcell is coupled to the non-inverting input terminal V1 of the comparator U1; the inverting input terminal V2 of the comparator U1 is coupled to the charge-disable voltage; the negative terminal of the battery cell Vcell is connected to reference ground; the output terminal VOUT of the comparator U1 is coupled to the input terminal VDD2 of the fuel gauge U2; the output terminal SWI1 of the fuel gauge U2 is coupled to the input terminal SWI2 of the control chip U4; the first terminal of the switching circuit 102 is coupled to the positive terminal of the battery cell Vcell; the second terminal of the switching circuit 102 is coupled to the external device 20; and the third terminal of the switching circuit 102 is coupled to the output terminal SWI3 of the control chip U4.

[0037] Among them, the control chip U4 obtains the status information of the fuel meter U2. When the status information of the fuel meter U2 is in the first state, the control chip U4 controls the switch circuit 102 to disconnect, so as to prevent the external device 20 from charging the battery cell Vcell.

[0038] The following provides further explanation of the components involved in this embodiment:

[0039] The battery cell Vcell is a component that supplies power to the battery protection control circuit 100 provided in this embodiment, thereby providing power to the battery protection control circuit 100.

[0040] Comparator U1 is an electronic component used to compare two voltage signals.

[0041] In this embodiment, comparator U1 includes a total of five ports, and their functions are as follows:

[0042] The non-inverting input V1 and the inverting input V2, as follows Figure 3 As shown, the non-inverting input V1 of comparator U1 is connected to the positive terminal of cell Vcell to obtain the real-time voltage of cell Vcell; the inverting input V2 is input to the reference voltage of the current battery protection control circuit 100, which is also the charging disable voltage. How the charging disable voltage is obtained is described below.

[0043] The output terminal VOUT of comparator U1 is coupled to the fuel meter U2, so that comparator U1 can output the comparison result of the data at the non-inverting input terminal V1 and the inverting input terminal V2 as a level signal to the fuel meter U2.

[0044] The operating voltage terminal VDD1 of comparator U1 is connected to the power supply to power comparator U1. It should be noted that in this embodiment, the power supply that powers the comparator is also the source cell Vcell from which the non-inverting input terminal V1 obtains data.

[0045] The ground reference terminal VSS of comparator U1 is used to connect to the reference ground.

[0046] Fuel meter U2 is a device used to record whether the cell voltage is lower than the charging threshold voltage. When the cell voltage is higher than the charging threshold voltage, fuel meter U2 receives a high level and the state information of fuel meter U2 is in the second state; when the cell voltage is less than or equal to the charging threshold voltage, fuel meter U2 receives a low level and the state information of fuel meter U2 is in the first state. After the state of fuel meter U2 switches to the first state, it cannot switch back to the second state.

[0047] The input terminal VDD2 of the fuel meter U2 is connected to the output terminal VOUT of the comparator U1, so that it can receive the level signal provided by the output terminal VOUT of the comparator U1.

[0048] The control chip U4 is used to control the entire battery protection control circuit 100. In this embodiment, the control chip U4 can be a microcontroller unit (MCU).

[0049] The switching circuit 102 is located between the external device 20 and the battery cell. When the switching circuit 102 is in the on state, the external device 20 can charge the battery cell. When the switching circuit 102 is in the off state, the external device 20 is prohibited from charging the battery cell. The external device 20 can be a charger.

[0050] Figure 3 Devices and Figure 1 The relationship is formed by comparator U1, first resistor R1, second resistor R2, and third resistor R3 (the three resistors will be described in detail later). Figure 1 The control circuit, the fuel gauge U2 is... Figure 1 The power meter, the control chip U4 is Figure 1 The control chip, path management chip U3 is... Figure 1 The path management chip has the following components: the grounding terminal GND1 of the power meter U2 is grounded, the grounding terminal GND2 of the control chip U4 is grounded, and the grounding terminal GND3 of the path management chip U3 is grounded. Figure 1 The battery protection circuit in Figure 3 Not shown in the image. The first metal-oxide-semiconductor transistor Q1 and the second metal-oxide-semiconductor transistor Q2 are equivalent to... Figure 1 The protection MOSFET.

[0051] In this scenario, the phone initially has a preset charging-off voltage, for example, 0.2 volts (Volt, V). In this case, comparator U1 reads the charging-off voltage and the value of the non-inverting input V1 of the battery cell (e.g., 0.1V), and compares the two. If the battery cell voltage obtained at the non-inverting input V1 is already lower than the charging-off voltage, comparator U1 outputs a low-level signal to the fuel gauge U2 through its output VOUT.

[0052] In this situation, the fuel gauge U2 receives a low-level signal at the output terminal VOUT of the comparator U1, meaning the fuel gauge U2 is powered off. At this time, the status information of the fuel gauge U2 is in the first state.

[0053] Then, the control chip U4 obtains the status information of the fuel gauge U2. When it is determined that the status information of the fuel gauge U2 is in the first state, it determines that the voltage of the battery cell Vcell is too low, that is, the remaining power is too low. Therefore, it uses a control command to prevent the power supply to the mobile phone through the charger, thereby achieving charging disabling.

[0054] It should be understood that the charging-stop voltage mentioned in this application does not actually mean that the cell voltage is 0 at this moment, but rather that the current cell voltage is at a very low level relative to the voltage of a normally functioning device, or even close to 0. This application does not make any special limitation on the specific value of the charging-stop voltage.

[0055] Additionally, in some scenarios, the original battery cells in the battery protection control circuit 100 may be removed or replaced, such as the situation described above where the protection board was removed to imitate an energy storage battery. The instant the battery cell is removed from the protection board, the voltage received at the non-inverting input of comparator U1 becomes 0, naturally less than the charging disable voltage. Comparator U1 outputs a low level, and the state information of the fuel gauge U2 is in the first state. When the control chip U4 determines that the fuel gauge U2 is in the first state, it disables the charging of the energy storage battery.

[0056] It is understandable that in this scenario, even if a new battery cell Vcell is reinstalled on the battery protection control circuit 100, the status information of the fuel gauge U2 cannot be changed. That is, through this setting, the battery protection control circuit 100 provided in this embodiment can permanently disable charging of the battery protection control circuit 100 that has had its battery cell removed.

[0057] In this embodiment, by setting up a battery cell Vcell, a comparator U1, a fuel gauge U2, a control chip U4, and a switching circuit 102, and by using the status information of the fuel gauge U2 to determine the status of the circuit and the battery cell, the charging protection of the battery cell is realized.

[0058] In some embodiments of this application, the fuel meter U2 stores a flag bit, which is consistent with the level value of the input terminal VDD2 of the fuel meter U2. When the flag bit is the first value, the state information of the fuel meter U2 is the first state.

[0059] In this embodiment, the fuel meter U2 stores a flag bit, which is consistent with the voltage level of the input terminal VDD2 of the fuel meter U2. When the flag bit is a first value, the state information of the fuel meter U2 is a first state, and when the flag bit is a second value, the state information of the fuel meter U2 is a second state. The first value can be 0 and the second value can be 1.

[0060] In other words, when the cell voltage is higher than the charging restriction voltage, the fuel gauge U2 receives a high level and sets the flag to 1; when the cell voltage is not higher than the charging restriction voltage, the fuel gauge U2 receives a low level and sets the flag to 0. Then, the control chip U4 can read the flag bit in the fuel gauge U2, and when the flag bit is at its first value, it controls the charging of the cell Vcell to be prohibited.

[0061] It should be understood that the flag is set to 0, and even if the input of the fuel gauge U2 goes high, it cannot be pulled back. Therefore, even if the battery is placed back on the charger, charging will not continue.

[0062] In some embodiments of this application, such as Figure 3 As shown, the battery protection control circuit 100 also includes a first resistor R1.

[0063] The first resistor R1 is set between the input terminal VDD2 of the fuel meter U2 and the positive terminal of the battery cell Vcell.

[0064] It should be understood that in this embodiment, the first resistor R1 is actually a pull-up resistor.

[0065] As a pull-up resistor, the first resistor R1 can ensure the stability of the voltage input from the battery cell Vcell to the fuel gauge U2, so that when the battery protection control circuit 100 in this embodiment is in normal condition, the input voltage fluctuation is avoided and noise interference is reduced.

[0066] On the other hand, when in normal state, the battery cell Vcell supplies power to the fuel gauge U2 through the circuit containing the first resistor R1; when in the disabled state, the comparator U1 outputs a low level, which pulls the power supply of the input terminal VDD2 of the fuel gauge U2 low through the first resistor R1, so that the low level signal is normally sent to the fuel gauge U2, causing the value of the stored flag bit to change to the first value.

[0067] In this embodiment, by setting a first resistor R1 between the input terminal VDD2 of the fuel gauge U2 and the battery cell Vcell, the logic control of the battery protection circuit and the power supply management of the fuel gauge U2 are effectively realized, thereby reducing the circuit cost.

[0068] In some embodiments of this application, such as Figure 3 As shown, the battery protection control circuit 100 also includes a second resistor R2 and a third resistor R3; the fuel gauge U2 includes a feedback voltage terminal VREG; the feedback voltage terminal VREG is connected to the reference ground through the second resistor R2 and the third resistor R3 connected in series; the series connection point between the second resistor R2 and the third resistor R3 is coupled to the inverting input terminal V2 of the comparator U1.

[0069] In this embodiment, a second resistor R2 and a third resistor R3 are provided between the comparator U1, the fuel meter U2 and the ground terminal, and the series connection point between the second resistor R2 and the third resistor R3 is coupled to the inverting input terminal V2 of the comparator U1 to provide a charge-disable voltage.

[0070] In this embodiment, the charging voltage value can be set to V0, the voltage value set at the feedback voltage terminal VREG is VREG, the resistance value of the second resistor is R2, and the resistance value of the third resistor is R3.

[0071] from Figure 3 It can be seen that the second resistor R2 and the third resistor R3 actually act as a voltage divider here. Therefore, the method for calculating the charge-discharge voltage value input to the inverting input terminal V2 of comparator U1 is as follows:

[0072] V0 = VREG × [R3 / (R2+R3)];

[0073] Using the above formula, the charging prohibition voltage set on the current battery protection control circuit 100 can be easily calculated based on the voltage value set at the feedback voltage terminal VREG and the resistance values ​​of the second resistor R2 and the third resistor R3.

[0074] For example, in one of the application scenarios mentioned above, the battery protection control circuit 100 provided in this embodiment is installed in a mobile phone.

[0075] In a certain model of mobile phone, the value of the feedback voltage terminal VREG is set to 3V, the second resistor R2 is set to 1000 ohms (Ω), and the third resistor R3 is set to 2kΩ. Then, the charging prohibition voltage set on the battery protection control circuit 100 should be 2V.

[0076] In another model of mobile phone, the value of the feedback voltage terminal VREG is set to 3V, the second resistor R2 is set to 2kΩ, and the third resistor R3 is set to 4kΩ. Then, the charging prohibition voltage set on the battery protection control circuit 100 should be 2V.

[0077] In another model of mobile phone, the value of the feedback voltage terminal VREG is set to 3V, the second resistor R2 is set to 2kΩ, and the third resistor R3 is set to 1kΩ. Then, the charging prohibition voltage set on the battery protection control circuit 100 should be 1V.

[0078] Therefore, for the battery protection control circuit 100 provided in this embodiment, the actual factor determining the charging-stop voltage is the ratio of the resistance values ​​of the second resistor R2 and the third resistor R3. Provided that the battery protection control circuit 100 can operate normally, the resistance values ​​of the second resistor R2 and the third resistor R3 can be arbitrarily set.

[0079] Additionally, it can be understood that in this scenario, if the resistance value of the second resistor R2 is set to 0, that is, the second resistor is directly removed, then under the premise of ensuring the circuit is normal, no matter how the resistance value of the second resistor R2 is modified, the final output and feedback to the inverting input terminal V2 of the comparator U1 will be the same as the set value of the feedback voltage terminal VREG of the fuel gauge U2. That is, under this condition, the charging voltage of the battery protection control circuit 100 can no longer be adjusted.

[0080] Furthermore, in this scenario, if the resistance of the third resistor R3 is set to 0, i.e., directly removed, the inverting input V2 of comparator U1 will actually receive the same value as ground. In this case, the charge-disable voltage will be completely set to 0. The value input from the cell Vcell to the non-inverting input V1 will be higher than the value at the inverting input V2 at any given time during normal operation of the cell Vcell. Therefore, comparator U1 will always output a high level to the fuel gauge U2, keeping the flag bit at the second value.

[0081] It is understandable that in some scenarios, R2 and R3 can be replaced by a sliding rheostat or a similar structure. In this case, the two sections of resistance separated by the sliding rheostat actually serve the same function as the second resistor R2 and the third resistor R3.

[0082] In this embodiment, by setting the second resistor R2 and the third resistor R3, the charging voltage on the battery protection control circuit 100 can be flexibly adjusted, so that the battery protection control circuit 100 can be better adapted to a variety of different devices, effectively improving the versatility and flexibility of the devices.

[0083] In some embodiments of this application, the operating voltage terminal VDD1 of comparator U1 is coupled to the positive terminal of cell Vcell; the ground reference terminal VSS of comparator U1 is grounded.

[0084] In this embodiment, the operating voltage terminal VDD1 of comparator U1 is coupled to the battery cell Vcell, thereby ensuring that the battery cell Vcell directly supplies power to comparator U1 and preventing other devices from affecting the power supply to comparator U1. Based on this, continuous monitoring of the battery cell voltage by comparator U1 is further guaranteed.

[0085] In some embodiments of this application, the switching circuit 102 further includes: a path management chip U3 and a first metal-oxide-semiconductor transistor Q1; the source of the first metal-oxide-semiconductor transistor Q1 is coupled to the negative terminal of the battery cell Vcell, and the drain of the first metal-oxide-semiconductor transistor Q1 is connected to a reference ground; the input terminal VBAT of the path management chip U3 is coupled to the positive terminal of the battery cell Vcell; the first output terminal DSG of the path management chip U3 is coupled to the gate of the first metal-oxide-semiconductor transistor Q1 to control the discharge of the battery cell Vcell.

[0086] This embodiment includes a path management chip U3. It is a processing unit controlled by a control chip U4. The input terminal VBAT of the path management chip serves as the first terminal of the switching circuit 102, the second terminal VBUS of the path management chip serves as the second terminal of the switching circuit 102, and the third terminal SWI4 of the path management chip serves as the third terminal of the switching circuit 102.

[0087] In this embodiment, the path management chip U3 has a switch Q3. In response to an external attempt to charge the battery cell Vcell, the control chip U4 reads the flag bit in the fuel gauge U2. When the flag bit is read as low, the control chip U4 connects the circuit through the path management chip U3, thus charging the battery cell Vcell normally. When the flag bit is read as high, the control chip U4 disconnects the circuit through the path management chip U3, thereby prohibiting the charging operation and setting the circuit to a charging-disabled state.

[0088] In this embodiment, a first metal-oxide-semiconductor transistor Q1 is provided.

[0089] The first metal-oxide-semiconductor (MOS) transistor, Q1, is a field-effect transistor based on a metal-oxide-semiconductor structure. This device has three terminals: source, drain, and gate.

[0090] In this embodiment, the first metal-oxide-semiconductor (MOSFET) Q1 is an N-type MOSFET. This is one type of MOSFET, characterized in that when its gate is set to a low level, the gate is off, resulting in an open circuit between the source and drain; when its gate is set to a high level, the gate is on, resulting in a conduction circuit between the source and drain.

[0091] Specifically, the path management chip U3 controls the connection or disconnection of the circuit through the first metal-oxide-semiconductor (MOSFET) Q1. It can be understood that the path management chip U3 establishes a connection with the gate of the first MOSFET Q1. Therefore, when circuit connection is required, the path management chip U3 controls the gate of the first MOSFET Q1 to open, connecting the source and drain, thus enabling the entire battery protection management circuit to connect; when circuit disconnection is required, the path management chip U3 controls the gate of the first MOSFET Q1 to close, disconnecting the source and drain, thus enabling the entire battery protection management circuit to disconnect.

[0092] For example, in one of the application scenarios mentioned above, the battery protection control circuit 100 provided in this embodiment is installed in a mobile phone. When the phone is plugged into a charger and an attempt is made to charge the battery cell Vcell, the comparator U1 first outputs a comparison result of the battery cell voltage and the charging-prohibited voltage to the fuel gauge U2. Based on the comparison result, the fuel gauge U2 sets the stored flag bit to low or high. After that, the control chip U4 reads the value of the flag bit. When the value is low, it is determined that the phone is not in a charging-prohibited state, and the control loop is turned on through the path management chip U3. When the value is high, it is determined that the phone is in a charging-prohibited state, and the control loop is turned off through the path management chip U3, prohibiting this charging.

[0093] In some embodiments of this application, the following situations also exist:

[0094] When the voltage at the input terminal VBAT of the path management chip U3 is greater than the over-discharge protection voltage UVP of the cell Vcell, the first output terminal DSG of the path management chip U3 outputs a second value, controlling the first metal oxide semiconductor transistor Q1 to turn on, so as to allow the cell Vcell to discharge.

[0095] When the voltage at the input terminal VBAT of the path management chip U3 is less than or equal to the over-discharge protection voltage UVP of the cell Vcell, the first output terminal DSG of the path management chip U3 outputs a first value to control the first metal-oxide-semiconductor transistor Q1 to be turned off, thereby preventing the discharge of the cell Vcell.

[0096] The over-discharge protection voltage UVP is greater than the charging prohibition voltage.

[0097] In this embodiment, the battery protection control circuit 100 provided in this application further implements protection measures for the over-discharge scenario of the battery cell Vcell.

[0098] Specifically, in this embodiment, an undervoltage protection (UVP) voltage is set. The undervoltage protection (UVP) voltage is a voltage value used to indicate that the cell voltage of the battery protection control circuit 100 is low, but has not yet reached the charging prohibition voltage.

[0099] like Figure 3 As shown, the battery cell Vcell transmits its output voltage to the input terminal VBAT of the path management chip U3. Subsequently, when charging of the battery cell Vcell is required, the path management chip U3 controls the charging of the battery protection control circuit 100 based on a comparison between the voltage value at the input terminal VBAT and the preset over-discharge protection voltage UVP.

[0100] When the voltage at the input terminal VBAT of the path management chip U3 is greater than the over-discharge protection voltage UVP of the cell Vcell, the first output terminal DSG of the path management chip U3 outputs a second value, which is a high-level signal. After the gate of the first metal-oxide-semiconductor transistor Q1 receives the second value, the gate opens, thereby connecting the drain and source to each other, thus forming a complete circuit and causing the cell Vcell to discharge.

[0101] When the voltage at the input terminal VBAT of the path management chip U3 is less than or equal to the over-discharge protection voltage UVP of the cell Vcell, the first output terminal DSG of the path management chip U3 outputs a first value, which is a low-level signal. After the gate of the first metal-oxide-semiconductor transistor Q1 receives the first value, the gate is turned off, thereby disconnecting the drain and source terminals, making it impossible to form a complete circuit, and thus prohibiting the discharge of the cell Vcell.

[0102] In this embodiment, the gate of the first metal-oxide-semiconductor transistor Q1 is connected to the path management chip U3. Specifically, the first output terminal DSG of the path management chip U3 is connected to the gate of the first metal-oxide-semiconductor transistor Q1.

[0103] In one of the application scenarios mentioned above, the battery protection control circuit 100 provided in this embodiment is installed in a mobile phone.

[0104] In this scenario, the over-discharge protection voltage UVP is set to 2V, and the charge-stop voltage is set to 1V.

[0105] In one scenario, a phone charger is plugged in to charge the battery cell Vcell, which outputs 3.3V. At this time, the voltage VBAT input to the path management chip U3 is also 3.3V, exceeding the preset over-discharge protection voltage UVP. Therefore, the first output terminal DSG of the path management chip U3 outputs a high-level signal, controlling the gate of the first metal-oxide-semiconductor transistor Q1 to open, making the source and drain conduct, thus completing the circuit and allowing the phone to charge normally.

[0106] In another scenario, a phone charger is plugged in to charge the battery cell Vcell, which outputs 1.3V. At this point, the voltage VBAT input to the path management chip U3 is also 1.3V, lower than the preset over-discharge protection voltage UVP but higher than the charging restriction voltage. Therefore, the first output terminal DSG of the path management chip U3 outputs a low-level signal, controlling the gate of the first metal-oxide-semiconductor transistor Q1 to turn off, disconnecting the source and drain, thus no longer forming a complete circuit. While Vcell can be charged at this point, the phone cannot power on normally due to the lack of a complete circuit. In this case, the charger needs to be connected again to continue charging Vcell until its output voltage exceeds the preset over-discharge protection voltage UVP before the phone can power on normally.

[0107] In this embodiment, by setting the over-discharge protection voltage UVP, the protection mechanism of the battery protection control circuit 100 is further improved. On the basis of prohibiting charging, over-discharge protection is introduced to effectively prevent the cell voltage from being too low, which can effectively extend the cell life and reduce the risk of circuit damage.

[0108] In some embodiments of this application, such as Figure 3 As shown, the switching circuit 102 also includes a second metal-oxide-semiconductor transistor Q2.

[0109] The drain of the second metal-oxide-semiconductor transistor Q2 is coupled to the drain of the first metal-oxide-semiconductor transistor Q1, and the source of the second metal-oxide-semiconductor transistor Q2 is coupled to reference ground; the second output terminal CHG of the path management chip U3 is coupled to the gate of the second metal-oxide-semiconductor transistor Q2 to control the charging of the battery cell Vcell.

[0110] In this embodiment, a second metal-oxide-semiconductor transistor Q2 is provided and coupled to the second output terminal CHG of the path management chip U3.

[0111] Similar to the first metal-oxide-semiconductor (MOSFET) Q1, the second MOSFET Q2 is also an N-type MOSFET. When its gate is set to a low level, the gate is off, resulting in an open circuit between the source and drain; when its gate is set to a high level, the gate is on, resulting in a conductive circuit between the source and drain.

[0112] In this embodiment, the second metal-oxide-semiconductor transistor Q2 is used to implement the charging control of the battery protection control circuit 100. When the voltage of the battery cell Vcell is too high or the circuit current is significantly too high, the path management chip U3 can control the gate of the second metal-oxide-semiconductor transistor Q2 to turn off, thereby disconnecting the complete circuit and preventing charging of the battery cell Vcell.

[0113] In one embodiment of this application, a battery protection control method is provided.

[0114] like Figure 4 As shown, the battery protection control method provided in this embodiment includes:

[0115] S102, input the output voltage of the battery cell to the non-inverting input terminal of the comparator, and input the charging disable voltage to the inverting input terminal of the comparator to obtain the status information of the fuel meter;

[0116] S104 obtains the status information of the fuel gauge through the control chip;

[0117] S106, when the status information of the fuel gauge is in the first state, the control chip controls the switch circuit to disconnect, so as to prevent external devices from charging the battery cell.

[0118] The steps of the battery protection control method in this embodiment will be further explained below.

[0119] When the external circuit charges the battery cell Vcell, the comparator U1 obtains the voltage value of the battery cell Vcell and the charging-disable voltage value provided by the fuel gauge U2 through the positive and negative input terminals, respectively. The two are compared in the comparator, and the comparator U1 will output different level signals according to the comparison result.

[0120] Specifically, when the voltage of the battery cell Vcell is greater than the charging disable voltage, the comparator U1 will output a high level to the fuel gauge U2. In response to this high level signal, the fuel gauge U2 will be in the second state.

[0121] When the voltage value of the battery cell Vcell is less than or equal to the charging disable voltage, the comparator U1 outputs a low level to the fuel gauge U2. In response to this low level signal, the fuel gauge U2 switches its state information to the first state.

[0122] After the state of the fuel gauge U2 is switched to the first state, it cannot be switched back to the second state.

[0123] The fuel meter U2 is equipped with a non-volatile memory, which is powered by the fuel meter and is used to store the value of the flag bit. When the flag bit is the first value, the status information of the fuel meter U2 is the first state, and when the flag bit is the second value, the status information of the fuel meter U2 is the second state. The first value can be 0 and the second value can be 1.

[0124] It should be noted that after the state of the fuel gauge U2 is switched to the first state, it cannot be switched back to the second state. In other words, the non-volatile memory will set the stored value to a low bit when the power is off, and it cannot be modified again after power is restored.

[0125] After this, when the status information of the fuel gauge is in the first state, that is, when the flag bit is set to low (first value), the control chip U4 controls the switch circuit to disconnect, so as to prevent charging of the battery cell Vcell.

[0126] Specifically, the control chip U4 controls the path management chip U3. The path management chip U3 controls the gate of the first metal-oxide-semiconductor transistor Q1 to turn off through the first output terminal, thereby disconnecting the source and drain, thus breaking the circuit and preventing charging of the battery cell Vcell.

[0127] The battery protection control method provided in this embodiment is applied to the battery protection control circuit 100 provided in the first aspect of this application. The comparator generates a level signal based on the real-time voltage and the charging prohibition voltage, which causes the flag bit in the fuel gauge to change. Then, the control chip controls the circuit to connect charging or disconnect charging prohibition, effectively improving the safety and flexibility of the entire battery protection management circuit.

[0128] like Figure 5 As shown, the battery protection control method provided in this embodiment further includes:

[0129] S202, obtain the comparison result between the voltage at the input terminal of the path management chip and the over-discharge protection voltage of the battery cell;

[0130] S204: When the voltage at the input terminal of the path management chip is greater than the over-discharge protection voltage of the battery cell, the first output terminal is controlled to output a second value to control the first metal-oxide-semiconductor transistor to conduct, so as to allow the battery cell to discharge, wherein the over-discharge protection voltage is greater than the charging prohibition voltage.

[0131] In this embodiment, after the battery cell Vcell transmits its output voltage to the input terminal VBAT of the path management chip U3, when it is necessary to charge the battery cell Vcell, the path management chip U3 controls the charging of the battery protection control circuit 100 based on the comparison result between the voltage value of the input terminal VBAT and the preset over-discharge protection voltage UVP.

[0132] When the voltage at the input terminal VBAT of the path management chip U3 is greater than the over-discharge protection voltage UVP of the cell Vcell, the first output terminal DSG of the path management chip U3 outputs a second value, which is a high-level signal. After the gate of the first metal-oxide-semiconductor transistor Q1 receives the second value, the gate opens, thereby connecting the drain and source to each other, thus forming a complete circuit and causing the cell Vcell to discharge.

[0133] like Figure 6 As shown, the battery protection control method provided in this embodiment further includes:

[0134] S302, obtain the comparison result between the voltage at the input terminal of the path management chip and the over-discharge protection voltage of the battery cell;

[0135] S304, when the voltage at the input terminal of the path management chip is less than or equal to the over-discharge protection voltage of the battery cell, controls the first output terminal to output a first value to control the first metal-oxide-semiconductor transistor to be turned off, so as to prevent the battery cell from discharging, wherein the over-discharge protection voltage is greater than the charging-off voltage.

[0136] In this embodiment, after the battery cell Vcell transmits its output voltage to the input terminal VBAT of the path management chip U3, when it is necessary to charge the battery cell Vcell, the path management chip U3 controls the charging of the battery protection control circuit 100 based on the comparison result between the voltage value of the input terminal VBAT and the preset over-discharge protection voltage UVP.

[0137] When the voltage at the input terminal VBAT of the path management chip U3 is less than or equal to the over-discharge protection voltage UVP of the cell Vcell, the first output terminal DSG of the path management chip U3 outputs a first value, which is a low-level signal. After the gate of the first metal-oxide-semiconductor transistor Q1 receives the first value, the gate is turned off, thereby disconnecting the drain and source terminals, making it impossible to form a complete circuit, and thus prohibiting the discharge of the cell Vcell.

[0138] In one embodiment of this application, an electronic device 10 is provided.

[0139] like Figure 7As shown, the electronic device 10 provided in this embodiment is equipped with a battery protection control circuit 100 as provided in the first aspect of this application. When the electronic device 10 needs to be charged, the battery protection control circuit 100 determines whether it can be charged based on the current cell voltage of the system power supply. If the cell voltage is less than a preset charging prohibition voltage, the charging of the cell is prohibited, thereby playing a role in preventing charging of the electronic device 10.

[0140] It should be noted that the electronic device 10 in this embodiment can be a home electronic device that powers mobile phones, laptops, etc., or an outdoor electronic device that powers outdoor live streaming equipment, large outdoor facilities, etc.

[0141] It should be understood that the device provided in this embodiment is equipped with the battery protection control circuit 100 as provided in the first aspect of this application, and therefore has all the beneficial technical effects of the battery management system shutdown control circuit in any of the above embodiments.

[0142] In this application, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise expressly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can mean a fixed connection, a detachable connection, or an integral connection; "link" can mean a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0143] In the description of this application, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0144] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to specific features, structures, materials, or characteristics described in connection with an embodiment or example that are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0145] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery protection control circuit, characterized in that, The device includes a battery cell, a comparator, a fuel gauge, a control chip, and a switching circuit. The positive terminal of the battery cell is coupled to the non-inverting input of the comparator, the inverting input of the comparator is coupled to a charge-disabled voltage, the negative terminal of the battery cell is connected to a reference ground, the output of the comparator is coupled to the input of the fuel gauge, the output of the fuel gauge is coupled to the input of the control chip, the first terminal of the switching circuit is coupled to the positive terminal of the battery cell, the second terminal of the switching circuit is coupled to an external device, and the third terminal of the switching circuit is coupled to the output of the control chip. The control chip acquires the status information of the fuel gauge. When the status information of the fuel gauge is in a first state, the control chip controls the switching circuit to disconnect, thereby preventing the external device from charging the battery cell.

2. The battery protection control circuit according to claim 1, characterized in that, The fuel gauge stores a flag bit, which is consistent with the voltage level of the input terminal of the fuel gauge. When the flag bit is a first value, the status information of the fuel gauge is the first state.

3. The battery protection control circuit according to claim 1, characterized in that, The battery protection control circuit further includes a first resistor, wherein the input terminal of the fuel gauge is coupled to the positive terminal of the battery cell through the first resistor.

4. The battery protection control circuit according to claim 1, characterized in that, The battery protection control circuit further includes a second resistor and a third resistor. The fuel gauge includes a feedback voltage terminal, which is connected to a reference ground via the second resistor and the third resistor connected in series. The series connection point between the second resistor and the third resistor is coupled to the inverting input terminal of the comparator.

5. The battery protection control circuit according to claim 1, characterized in that, The operating voltage terminal of the comparator is coupled to the positive terminal of the battery cell; The ground reference terminal of the comparator is grounded.

6. The battery protection control circuit according to claim 1, characterized in that, The switching circuit includes: The circuit includes a path management chip and a first metal-oxide-semiconductor (MOSFET), wherein the source of the first MOSFET is coupled to the negative terminal of the battery cell, and the drain of the first MOSFET is connected to a reference ground; the input terminal of the path management chip is coupled to the positive terminal of the battery cell; and the first output terminal of the path management chip is coupled to the gate of the first MOSFET to control the discharge of the battery cell.

7. The battery protection control circuit according to claim 6, characterized in that, When the voltage at the input terminal of the path management chip is greater than the over-discharge protection voltage of the battery cell, the first output terminal of the path management chip outputs a second value to control the first metal-oxide-semiconductor transistor to turn on, thereby allowing the battery cell to discharge, wherein the over-discharge protection voltage is greater than the charging-disable voltage.

8. The battery protection control circuit according to claim 6, characterized in that, When the voltage at the input terminal of the path management chip is less than or equal to the over-discharge protection voltage of the battery cell, the first output terminal of the path management chip outputs a first value to control the first metal-oxide-semiconductor transistor to be turned off, thereby prohibiting the discharge of the battery cell, wherein the over-discharge protection voltage is greater than the charge-stop voltage.

9. The battery protection control circuit according to claim 6, characterized in that, The switching circuit further includes a second metal-oxide-semiconductor (MOSFET), wherein the drain of the second MOSFET is coupled to the drain of the first MOSFET, and the source of the second MOSFET is coupled to a reference ground; the second output terminal of the path management chip is coupled to the gate of the second MOSFET to control the charging of the battery cell.

10. A battery protection control method, used in a battery protection control circuit as described in any one of claims 1 to 9, characterized in that, include: The output voltage of the battery cell is input to the non-inverting input of the comparator, and the charging disable voltage is input to the inverting input of the comparator to obtain the status information of the fuel meter. The status information of the fuel gauge is obtained through the control chip; When the status information of the fuel gauge is in the first state, the control chip controls the switching circuit to disconnect, thereby preventing external devices from charging the battery cell.

11. An electronic device, characterized in that, It includes a battery protection control circuit according to any one of claims 1 to 9.

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