Battery protection circuit of controllable ship evacuation mode, battery assembly and electronic device

Abstract

The application provides a battery protection circuit with controllable de-shipping mode, a battery assembly and an electronic device. The working mode of the battery protection circuit includes a shipping mode and a normal mode. The battery protection circuit further includes a de-shipping end and a first processing unit. The de-shipping end is connected with the first processing unit. The first processing unit is connected with a main control unit. Therefore, when the battery protection circuit is in the shipping mode and the first processing unit detects that the de-shipping end meets a preset condition, the first processing unit outputs a de-shipping enable signal to make the main control unit control the battery protection circuit to enter the normal mode. In the normal mode, a main switch unit is turned on to make the battery supply power to a system circuit. Further, the de-shipping end and a system end are connected with two ends of a switch control key. A user triggers the battery protection circuit to enter the normal mode from the shipping mode by operating the switch control key. The user does not need to connect a charger, and the use experience of the user is improved.

Description

Technical Field

[0001] This application relates to the field of battery protection technology, and in particular to a battery protection circuit, battery assembly, and electronic device for a controllable return shipping mode. Background Technology

[0002] Battery modules are widely used in electronic devices such as Bluetooth headsets, mobile phones, tablets, and smart glasses to provide a more flexible operating environment, freeing them from the constraints of sockets and power supply cables. Generally speaking, a battery module includes a bare battery and a battery protection circuit electrically connected to the bare battery to prevent overcharging or over-discharging.

[0003] After electronic devices with battery components are manufactured in the factory, the battery components are charged to a preset power level and the electronic devices are turned off. After a long period of transportation and storage, when the end user finally receives the electronic device for the first time, due to the long transportation and storage, the electronic device may be completely discharged due to the consumption of internal current. Therefore, the end user must charge the electronic device to restore its power before the first use, resulting in a poor user experience.

[0004] The applicant of this application filed a prior Chinese patent application, CN202010881223.9, entitled "A Battery Protection Circuit, Battery Component, and Electronic Device," which proposed to improve the above-mentioned technical problem by adding a shipping mode. When the battery protection circuit enters the shipping mode, at least some units of the battery protection circuit are de-energized, and the battery stops supplying power to the system circuit, thereby reducing the current consumption of the battery during transportation and storage and improving the battery's charge retention time. However, when exiting the shipping mode, a charger needs to be connected to the battery protection circuit. That is, the battery protection circuit will only exit the shipping mode when it detects that a charger is connected.

[0005] However, in some scenarios, users may not have a charger with them and may not be able to trigger the battery protection circuit to exit shipping mode by charging, resulting in the electronic device not working properly and thus a poor user experience. Summary of the Invention

[0006] This application addresses the poor user experience caused by the requirement of connecting a charger to the return shipping mode in existing battery protection circuits. It provides a battery protection circuit, battery component, and electronic device with a controllable return shipping mode, which is simple to implement and provides a good user experience.

[0007] To address the aforementioned technical problems, the first aspect of this application provides a battery protection circuit for a controllable return shipping mode, comprising:

[0008] The system includes a power supply terminal, a power ground terminal, a system terminal, a main control unit, and a main switch unit. The power supply terminal is used to connect to the positive terminal of the battery, and the power ground terminal is used to connect to the negative terminal of the battery. The main control unit is electrically connected to the control terminal of the main switch unit. The first terminal of the main switch unit is connected to the power supply terminal or the power ground terminal, and its second terminal is connected to the system circuit via the system terminal.

[0009] The system includes a return shipping terminal and a first processing unit, wherein the return shipping terminal is connected to the first processing unit, and the first processing unit is also connected to the main control unit.

[0010] The battery protection circuit operates in two modes: a shipping mode and a normal mode. In the shipping mode, the main switch unit is disconnected to stop the battery from supplying power to the system circuit. When the battery protection circuit is in the shipping mode and the first processing unit detects that the return shipping end meets the preset conditions, the first processing unit outputs a return shipping enable signal to enable the main control unit to control the battery protection circuit to enter the normal mode. In the normal mode, the main switch unit is turned on to allow the battery to supply power to the system circuit.

[0011] Optionally, in shipping mode, if the voltage at the return shipping terminal meets a preset threshold condition, the first processing unit detects that the return shipping terminal meets the preset condition.

[0012] Optionally, the first processing unit includes a threshold detection branch and a first voltage comparison unit;

[0013] The threshold detection branch has its first end connected to the power supply terminal, its second end connected to the power ground terminal, its input terminal connected to the ship return terminal, its output terminal connected to the input terminal of the first voltage comparison unit, and the output terminal of the first voltage comparison unit connected to the main control unit.

[0014] In shipping mode, if the voltage at the return shipping end meets the first preset threshold, the threshold detection branch outputs the first voltage value, and the first processing unit determines whether to output the return shipping enable signal based on the comparison result of the first voltage value by the first voltage comparison unit.

[0015] Optionally, the threshold detection branch includes a first current source and a branch switch connected in series. The control terminal of the branch switch is connected to the ship return end, and the first connection point of the first current source and the branch switch is connected to the input terminal of the first voltage comparison unit.

[0016] When the voltage at the return shipping end meets a preset threshold, the state of the branch switch tube changes from a first switch state to a second switch state, and the threshold detection branch outputs a first voltage value through the first connection point.

[0017] Optionally, the first processing unit includes a second voltage comparison unit; the second voltage comparison unit has its input terminal connected to the return shipping end and its output terminal electrically connected to the main control unit;

[0018] In shipping mode, the first processing unit determines whether to output a shipping return enable signal based on the comparison result of the voltage of the return shipping terminal by the second voltage comparison unit.

[0019] Optionally, the first processing unit is also connected to the system terminal. In shipping mode, when the first processing unit detects that the voltage at the return shipping terminal and the voltage at the system terminal meet preset conditions, the first processing unit outputs a return shipping enable signal so that the main control unit controls the battery protection circuit to enter normal mode.

[0020] Optionally, the preset condition includes that the absolute value of the difference between the voltage at the return shipping end and the voltage at the system end is less than or equal to a first voltage threshold; or,

[0021] The absolute value of the difference between the voltage at the return shipping end and the voltage at the system end is a first intermediate value. The preset condition includes the ratio of the first intermediate value to the voltage at the return shipping end or to the voltage at the system end being less than or equal to a first ratio threshold; or,

[0022] The preset conditions include the ratio of the voltage at the return shipping end to the voltage at the system end being greater than or equal to a second ratio threshold, or the ratio of the voltage at the return shipping end to the voltage at the system end being less than or equal to a third ratio threshold.

[0023] Optionally, the first processing unit includes a third voltage comparison unit, wherein the first input terminal of the third voltage comparison unit is electrically connected to the ship return end, the second input terminal is electrically connected to the system end, and the output terminal is connected to the main control unit.

[0024] In shipping mode, when the absolute value of the difference between the voltage at the return shipping end and the voltage at the system end is less than or equal to a first voltage threshold, the third voltage comparison unit outputs a first comparison signal, and the first processing unit determines whether to output a return shipping enable signal based on the first comparison signal; when the absolute value of the difference between the voltage at the return shipping end and the voltage at the system end is greater than the first voltage threshold, the third voltage comparison unit outputs a second comparison signal, and the first comparison signal is different from the second comparison signal.

[0025] Optionally, the first processing unit includes a delay branch, which is used to time the duration for which the return shipping end meets the preset conditions. When the return shipping end meets the preset conditions and the duration of the delay branch is greater than a first preset duration, the first processing unit outputs a return shipping enable signal so that the main control unit controls the battery protection circuit to enter the normal mode.

[0026] Optionally, the return shipping end is used to connect to the first end of the switch control key, and the system end is used to connect to the second end of the switch control key;

[0027] When the battery protection circuit is in shipping mode and the switch control key changes from the off state to the on state, the first processing unit detects that the return shipping end meets the preset conditions.

[0028] Optionally, if the main switch unit is electrically connected between the power supply ground terminal and the system terminal, then the system terminal is connected to the power supply terminal via the first switch, and the ship retraction terminal is connected to the power supply ground terminal via the first resistor; or, if the main switch unit is electrically connected between the power supply terminal and the system terminal, then the system terminal is connected to the power supply ground terminal via the first switch, and the ship retraction terminal is connected to the power supply terminal via the first resistor.

[0029] In shipping mode, the first switch is turned on, and the return shipping end and the system end are disconnected. When the return shipping end and the system end are electrically connected, the first processing unit detects that the return shipping end meets the preset conditions.

[0030] Optionally, the battery protection circuit further includes a shipping terminal, a shipping identification unit, and an over-discharge voltage protection unit. The main control unit includes a first logic unit and a main logic unit. The first input terminal of the first logic unit is connected to the system terminal, its second input terminal is connected to the shipping identification unit, its third input terminal is connected to the over-discharge voltage protection unit, the shipping terminal is connected to the shipping identification unit, and the output terminal of the first logic unit is connected to the main logic unit.

[0031] In shipping mode, the first input terminal of the first logic unit is a first level signal, its second input terminal is a second level signal, its third input terminal is a third level signal, and the main logic unit receives a fourth level signal. When the first processing unit outputs a shipping reversal enable signal, at least one of the first level signal, the second level signal, the third level signal, and the fourth level signal changes, and the main control unit controls the battery protection circuit to enter normal mode.

[0032] Optionally, the battery protection circuit further includes a second logic unit, wherein the first input terminal of the second logic unit is connected to the output terminal of the first processing unit, the second input terminal is connected to the system terminal, and the output terminal is connected to the first input terminal of the first logic unit.

[0033] When the first processing unit outputs a ship return enable signal to the first input terminal of the second logic unit, the second logic unit outputs a fifth level signal, which is different from the first level signal, to change the first level signal received by the first input terminal of the first logic unit, thereby changing the fourth level signal received by the main logic unit, so as to trigger the main control unit to control the battery protection circuit to enter the normal mode.

[0034] Optionally, the battery protection circuit further includes a third logic unit, wherein the first input terminal of the third logic unit is connected to the output terminal of the first processing unit, the second input terminal is connected to the output terminal of the shipping identification unit, and the output terminal is connected to the second input terminal of the first logic unit.

[0035] When the first processing unit outputs a ship return enable signal to the first input terminal of the third logic unit, the third logic unit outputs a sixth level signal, which is different from the second level signal, to change the second level signal received by the second input terminal of the first logic unit, thereby changing the fourth level signal received by the main logic unit, so as to trigger the main control unit to control the battery protection circuit to enter the normal mode.

[0036] Optionally, the battery protection circuit further includes a fourth logic unit, wherein the first input terminal of the fourth logic unit is connected to the output terminal of the first processing unit, the second input terminal is connected to the output terminal of the over-discharge voltage protection unit, and the output terminal is connected to the third input terminal of the first logic unit.

[0037] When the first processing unit outputs a ship return enable signal to the first input terminal of the fourth logic unit, the fourth logic unit outputs a seventh level signal, which is different from the third level signal, to change the third level signal received by the third input terminal of the first logic unit, thereby changing the fourth level signal received by the main logic unit, so as to trigger the main control unit to control the battery protection circuit to enter the normal mode.

[0038] Optionally, the first logic unit further includes a fourth input terminal, which is connected to the output terminal of the first processing unit.

[0039] When the first processing unit outputs a return-to-ship enable signal to the fourth input terminal of the first logic unit, the level signal at the output terminal of the first logic unit changes, thereby changing the fourth level signal received by the main logic unit, which in turn triggers the main control unit to control the battery protection circuit to enter normal mode.

[0040] Optionally, the main control unit further includes a fifth logic unit, wherein the first input terminal of the fifth logic unit is connected to the output terminal of the first processing unit, the second input terminal is connected to the output terminal of the first logic unit, and the output terminal is connected to the main logic unit;

[0041] When the first processing unit outputs a ship return enable signal to the first input terminal of the fifth logic unit, the fifth logic unit outputs an eighth level signal to change the fourth level signal received by the main logic unit, thereby triggering the main control unit to control the battery protection circuit to enter normal mode.

[0042] Optionally, the battery protection circuit further includes an over-discharge voltage protection unit, and the main control unit includes a sixth logic unit and a main logic unit. The first input terminal of the sixth logic unit is connected to the system terminal, its second input terminal is connected to the over-discharge voltage protection unit, and the output terminal of the sixth logic unit is connected to the main logic unit.

[0043] In shipping mode, the first input of the sixth logic unit is a first-level signal, its second input is a third-level signal, and the main logic unit receives a fourth-level signal. When the first processing unit outputs a shipping reversal enable signal, at least one of the first-level signal, the third-level signal, and the fourth-level signal changes, and the main control unit controls the battery protection circuit to enter normal mode.

[0044] Optionally, the battery protection circuit is located on the same chip; or,

[0045] The battery protection circuit, excluding the main switch unit, has its components located on one chip, while the main switch unit is located on another chip.

[0046] Secondly, embodiments of this application provide a battery assembly, including:

[0047] Battery;

[0048] The battery protection circuit as described in the first aspect is connected to the battery.

[0049] Thirdly, embodiments of this application provide an electronic device, including:

[0050] The battery protection circuit as described in the first aspect or the battery assembly as described in the second aspect;

[0051] The system circuit is connected to the battery via the main switching unit of the battery protection circuit;

[0052] A switch control key, the two ends of which are electrically connected to the return end and the system end of the battery protection circuit, respectively.

[0053] In the shipping mode, if the switch control key changes from the off state to the on state, the battery protection circuit enters the normal mode, and in the normal mode, the battery supplies power to the system circuit.

[0054] Optionally, the system circuit includes a processor and a load circuit. The processor is used to detect the operating state of the load circuit. When it detects that the load circuit has stopped working and the duration of the stop working is longer than a preset duration, it outputs a shipping entry signal to the battery protection circuit so that the battery protection circuit enters the shipping mode.

[0055] Optionally, the switch key is a function control key of the electronic device.

[0056] In the embodiments of this application, the battery protection circuit operates in two modes: a shipping mode and a normal mode. In shipping mode, the main switch unit is disconnected to stop the battery from supplying power to the system circuit. Furthermore, the battery protection circuit includes a return-to-ship terminal and a first processing unit. The return-to-ship terminal is connected to the first processing unit, which is connected to the main control unit. Therefore, when the battery protection circuit is in shipping mode and the first processing unit detects that the return-to-ship terminal meets preset conditions, the first processing unit outputs a return-to-ship enable signal, causing the main control unit to control the battery protection circuit to enter normal mode. In normal mode, the main switch unit is turned on to supply power to the system circuit. Further, a switch control key is connected between the return-to-ship terminal and the system terminal. This key can be an existing function button on the electronic device. The user can change the signal of the return-to-ship terminal by operating this switch control key, thereby triggering the battery protection circuit to switch from shipping mode to normal mode. This eliminates the need for a charger connection, improving the user experience. Attached Figure Description

[0057] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1a and Figure 1bThese are schematic diagrams illustrating two structural configurations of the electronic device provided in the embodiments of this application;

[0059] Figure 2 This is a schematic diagram of the battery protection circuit module in the electronic device shown in Figure 1;

[0060] Figures 3a to 3d This is a schematic diagram illustrating the working principle of the battery protection circuit provided in the first embodiment of this application;

[0061] Figure 4 This is a schematic diagram of a battery protection circuit provided in the first embodiment of this application;

[0062] Figures 5a to 5e This is a schematic diagram of the structure when the first processing unit acts on different components of the battery protection circuit;

[0063] Figure 6 This is another schematic diagram of the battery protection circuit provided in the first embodiment of this application;

[0064] Figure 7a and Figure 7b This is a schematic diagram illustrating the working principle of the battery protection circuit provided in the second embodiment of this application;

[0065] Figure 8a and Figure 8b This is a schematic diagram illustrating the working principle of the battery protection circuit provided in the third embodiment of this application. Detailed Implementation

[0066] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0067] The terms "comprising" and "having," and any variations thereof, appearing in this application specification, claims, and drawings, are intended to cover a non-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 may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices. Furthermore, the terms "first," "second," and "third," etc., are used to distinguish different objects and are not used to describe a specific order. Connections in this application include direct connections and indirect connections; an indirect connection refers to the presence of other electronic components, pins, etc., between the two connected components. Terminals mentioned in this application may or may not be actual terminals, such as simply one end of a component or one end of a wire. The application mentions and / or includes three cases, such as A and / or B, including cases A, B, and A and B.

[0068] First Embodiment

[0069] This application provides an electronic device, such as a Bluetooth headset, mobile phone, tablet computer, smart glasses, smartwatch, smart bracelet, or other device with a power switch. Figure 1a and Figure 1b These are schematic diagrams illustrating two structural configurations of the electronic device provided in the embodiments of this application. Please refer to... Figure 1a and Figure 1bThe electronic device includes a battery assembly, a system circuit 200, and a power switch K0. The system circuit 200 includes at least one of the following: a microprocessor, a camera driver circuit, an image processor, an audio processing circuit, or a Bluetooth processing circuit. The system circuit 200 is electrically connected to the battery assembly, which supplies power to the system circuit 200. The power switch K0 is typically a function control key for the electronic device, such as a power button, which controls functions like turning the device on / off or waking it up. The battery assembly includes a battery 100 and a battery protection circuit 300. The battery protection circuit 300 is electrically connected to the positive and negative terminals of the battery 100. The system circuit 200 is electrically connected to the battery protection circuit 300. The battery 100 supplies power to the battery protection circuit 300, which protects the battery 100, for example, by overcharging or over-discharging it. In this embodiment, the number of batteries 100 is one or more. When there are multiple batteries, they can be connected in parallel, in series, or in a combination of series and parallel. The electronic device can be configured according to actual needs. The battery 100 is preferably a lithium battery with a capacity of, for example, 10mAh-5000mAh, such as 10mAh, 20mAh, 30mAh, 40mAh, 50mAh, 60mAh, 70mAh, 80mAh, 100mAh, 500mAh, 1000mAh, 2000mAh, 3000mAh, 4000mAh, 5000mAh, etc. Preferably, the capacity of the battery 100 is 20mAh-80mAh. In this case, the battery 100 is small in size and can be easily configured in small electronic devices, such as smartwatches, smart bracelets, smart glasses, and Bluetooth headsets. In this embodiment, a resistor R0 and a capacitor C1 are provided between the battery protection circuit 300 and the battery 100, and the resistor R0 and capacitor C1 are used for filtering. In other embodiments of this application, the resistor R0 and capacitor C1 may not be provided between the battery protection circuit 300 and the battery 100, and other circuits or electronic components may also be provided.

[0070] Figure 2 This is a schematic diagram of the battery protection circuit module in the electronic device shown in Figure 1. Please refer to [the diagram for further details]. Figure 1a and Figure 2In this embodiment, the battery protection circuit 300 is used to protect the battery 100 from damage caused by over-discharge voltage, over-charge voltage, over-current charging, over-discharge, over-temperature, etc., thus preventing damage to the battery 100 itself. In this application, the battery protection circuit 300 includes a power supply terminal VDD, a power ground terminal GND, a system terminal VM, a battery protection module, and a main switch unit 400. The battery protection module includes a reference voltage generation unit 301 (i.e., BG 301), a discharge overcurrent protection unit 302 (i.e., ODC 302), an overcharge voltage protection unit 303 (i.e., OCV 303), a charging overcurrent protection unit 304 (i.e., OCC 304), and an over-discharge voltage protection unit 306 (i.e., ODV 306). 306), voltage sampling unit 308, main control unit 320, etc. The power supply terminal VDD and power ground terminal GND are electrically connected to the positive and negative terminals of the battery 100, respectively, so that the battery 100 can supply power to the battery protection circuit 300. The system terminal VM is used to connect to the system circuit 200. The output terminals of the discharge overcurrent protection unit 302, overcharge voltage protection unit 303, charging overcurrent protection unit 304, and overdischarge voltage protection unit 306 are respectively connected to the main control unit 320. The main control unit 320 is electrically connected to the control terminal of the main switch unit 400. The first terminal of the main switch unit 400 is connected to the power supply terminal VDD or the power ground terminal GND, and its second terminal is connected to the system circuit via the system terminal VM.

[0071] In this embodiment, the reference voltage generating unit 301 is connected to the discharge overcurrent protection unit 302, the overcharge voltage protection unit 303, the charging overcurrent protection unit 304, and the over-discharge voltage protection unit 306, respectively. Thus, the reference voltage generating unit 301 provides reference thresholds for the overcharge voltage protection unit 303, the discharge overcurrent protection unit 302, the charging overcurrent protection unit 304, and the over-discharge voltage protection unit 306, thereby determining whether the battery 100 is in an overcharge voltage state, a discharge overcurrent state, a charging overcurrent state, or an over-discharge voltage state.

[0072] In this embodiment, the input terminal of the voltage sampling unit 308 is connected to the power supply terminal VDD, and its output terminal is connected to an input terminal of the overcharge voltage protection unit 303 and an input terminal of the over-discharge voltage protection unit 306, respectively, for collecting the battery voltage and outputting it to the overcharge voltage protection unit 303 and the over-discharge voltage protection unit 306.

[0073] In this embodiment, the overcharge voltage protection unit 303 is used to protect the battery 100 when it detects that the voltage of the battery 100 is too high and exceeds the overcharge threshold during the charging process, such as stopping the charging of the battery 100, to prevent the battery 100 from being damaged by overcharging or causing safety problems.

[0074] In this embodiment, the discharge overcurrent protection unit 302 is used to protect the battery 100 when the discharge current is detected to be too large and exceeds the discharge current threshold during the discharge process of the battery 100, such as by stopping the battery 100 from discharging, to prevent the excessive discharge current from causing permanent damage to the battery 100 or causing safety problems.

[0075] In this embodiment, the charging overcurrent protection unit 304 is used to protect the battery 100 when it detects that the charging current is too large and exceeds the charging current threshold during the charging process of the battery 100, such as by stopping the charging of the battery 100, to prevent the excessive charging current from causing permanent damage to the battery 100 or causing safety problems.

[0076] In this embodiment, the over-discharge voltage protection unit 306 is used to protect the battery 100 when the battery 100 voltage is detected to be lower than the over-discharge threshold during the discharge process. For example, it controls the battery 100 to stop supplying power to the system circuit 200 to prevent the battery 100 from being over-discharged and causing permanent damage to the battery 100. That is, the battery protection circuit 300 enters the over-discharge mode.

[0077] In addition, in other embodiments of this application, the discharge overcurrent protection unit 302, overcharge voltage protection unit 303, charging overcurrent protection unit 304, overdischarge voltage protection unit 306, etc., can be set or not set as needed.

[0078] In this embodiment, the main control unit 320 is used to control the working state and control logic of each unit of the battery protection circuit 300, and to control whether the battery 100 discharges or is charged. The main control unit 320 can control the entire battery protection circuit 300 to be in a zero power consumption mode, that is, the entire battery protection circuit 300 consumes almost no power.

[0079] In this embodiment, the control terminal of the main switch unit 400 is connected to the main control unit 320. The connection between the main switch unit 400 and the battery 100 generally has the following two methods. Of course, those skilled in the art can also make simple modifications to the circuit described below as needed, which is also within the scope of this application.

[0080] 1. Please continue reading Figure 1a(This embodiment is described using this as an example.) The first terminal of the main switch unit 400 is connected to the negative terminal of the battery 100 (the main switch unit 400 is located below and externally, or the battery protection circuit 300 is referred to as the negative terminal lithium protection circuit). The second terminal of the main switch unit 400 is connected to the system circuit 200 and the system terminal VM. The control terminal of the main switch unit 400 is connected to the main control unit 320 of the battery protection circuit 300. Specifically, the battery protection circuit 300 also includes a switch control terminal CO / DO, which is electrically connected to the main control unit 320. The control terminal of the main switch unit 400 is also electrically connected to the switch control terminal CO / DO. In this embodiment, the main control unit 320 controls the main switch unit 400 to turn on or off via the switch control terminal CO / DO. Thus, when the main control unit 320 controls the main switch unit 400 to turn on, the battery 100 can supply power to the system circuit 200 through the main switch unit 400, and the system circuit 200 can work normally. When the main control unit 320 controls the main switch unit 400 to turn off, the battery 100 stops supplying power to the system circuit 200, the system circuit 200 is in a zero-power consumption mode (not considering leakage current), and the system circuit 200 does not work.

[0081] 2. Please see Figure 1b The first terminal of the main switch unit 400 is connected to the positive terminal of the battery 100 (the main switch unit 400 is located on top, or the battery protection circuit 300 is referred to as the positive lithium protection circuit). The second terminal of the main switch unit 400 is connected to the system circuit 200 and the system terminal VM. The control terminal of the main switch unit 400 is connected to the battery protection circuit 300. Specifically, the battery protection circuit 300 includes a switch control terminal CO / DO, which is electrically connected to the main control unit 320. The control terminal of the main switch unit 400 is electrically connected to the switch control terminal CO / DO. In this embodiment, the main control unit 320 controls the main switch unit 400 to turn on or off via the switch control terminal CO / DO. Thus, when the main control unit 320 controls the main switch unit 400 to turn on, the battery 100 can supply power to the system circuit 200 through the main switch unit 400, and the system circuit 200 can work normally. When the main control unit 320 controls the main switch unit 400 to turn off, the battery 100 stops supplying power to the system circuit 200, the system circuit 200 is in a zero-power consumption mode (not considering leakage current), and the system circuit 200 does not work.

[0082] In one of the two connection methods described above, the main switch unit 400 includes a charging switch and a discharging switch connected in series. The charging switch and discharging switch are MOS transistors or other suitable field-effect transistors, such as NMOS or PMOS. The charging switch and discharging switch are electrically connected to the main control unit 320, for example... Figure 1a and Figure 1b In one implementation, the battery protection circuit 300 has two switch control terminals, CO / DO, including a charging switch control terminal CO and a discharging switch control terminal DO. The charging switch control terminal CO is electrically connected to the control terminal of the charging switch, and the discharging switch control terminal DO is electrically connected to the control terminal of the discharging switch. Both the charging switch control terminal CO and the discharging switch control terminal DO are electrically connected to the main control unit 320, enabling the main control unit 320 to control the charging switch and the discharging switch separately. In another implementation, the main switch unit 400 includes a switching transistor, and the battery protection circuit 300 includes a substrate control circuit. The switching transistor is connected in series with the load. The switching transistor is a MOSFET or other field-effect transistor, etc. The control terminal of the switching transistor is electrically connected to the switch control terminals CO / DO. The substrate control circuit is electrically connected to the main control unit 320 and connected to the substrate of the switching transistor. The substrate control circuit is used to achieve correct biasing of the substrate of the switching transistor. The connection between the substrate control circuit and the switching transistor, and the relationship between the substrate control circuit and the main control unit 320, are conventional techniques in this field and will not be elaborated further. In another implementation, the main switch unit 400 can also be implemented in other ways, such as including only one switch transistor. The control terminal of the switch transistor is electrically connected to the main control unit 320 via the switch control terminal CO / DO. In this case, the switch transistor controls the discharge.

[0083] It is understood that in other embodiments of this application, the main switch unit 400 may be integrated within the battery protection circuit 300. As one example, the first terminal of the main switch unit 400 is connected to the power ground terminal GND, and the second terminal of the main switch unit 400 is connected to the system terminal VM (the main switch unit 400 is located below and built-in), with the system terminal VM connected to the system circuit 200. As another example, the first terminal of the main switch unit 400 is connected to the power supply terminal GND, and the second terminal of the main switch unit 400 is connected to the system terminal VM (the main switch unit 400 is located above and built-in), with the system terminal VM connected to the system circuit 200. In both examples, the battery protection circuit 300 may not include a switch control terminal CO / DO, and the control terminal of the main switch unit 400 is connected to the main control unit 320. The main control unit 320 can control the main switch unit 400 to turn on or off, thereby controlling whether the battery 100 supplies power to the system circuit 200.

[0084] To reduce standby power consumption during long-distance transportation, the applicant of this application previously proposed that the battery protection circuit 300 actively enter a shipping mode. That is, the battery protection circuit 300 operates in two modes: shipping mode and normal mode. In shipping mode, the main switch unit 400 is disconnected, causing the battery 100 to stop supplying power to the system circuit 200. As an example, one implementation of the battery protection circuit 300 entering shipping mode is to have the main control unit 320 receive an over-discharge signal. Using the existing over-discharge protection control circuit and logic, the main switch unit 400 is disconnected, and most or all of the circuit units in the battery protection circuit 300 cease power consumption. This significantly reduces the discharge of the battery 100, greatly extending its standby time. This method of enabling the battery protection circuit to enter shipping mode can reduce costs. As another example, see [reference needed]. Figure 2 As shown, the battery protection circuit 300 may further include a shipping terminal CTL and a shipping identification unit 307. In this case, the battery protection circuit 300 enters the shipping mode by connecting the output terminal of the shipping identification unit 370 to the over-discharge voltage protection unit 306 and the main control unit 320 respectively, and connecting the input terminal of the shipping identification unit 307 to the shipping terminal CTL. The shipping identification unit 307 is used to identify whether the signal received by the shipping terminal CTL is a shipping entry signal. When the shipping identification unit 307 confirms that the signal received by the shipping terminal CTL is a shipping entry signal, the shipping identification unit 370 outputs a shipping signal to enable the battery protection circuit to enter the shipping mode.

[0085] Optionally, the inbound shipping terminal CTL can be connected to the system circuit 200. The system circuit 200 can be connected to external devices via wired or wireless means, such as directly or indirectly connected to the central controller at the factory. Based on signals from the central controller, the system circuit can control whether the battery protection circuit 300 enters shipping mode. For example, when it is necessary to control the battery protection circuit 300 to enter shipping mode, the system circuit 200 can send a shipping entry signal to the inbound shipping terminal CTL. The shipping identification unit 307 identifies whether the signal received by the inbound shipping terminal CTL is a shipping entry signal. The shipping entry signal is an analog signal, a digital signal, or a mixed analog-digital signal pre-protocoled by the battery protection circuit 300 and the system circuit 200 during design. For the specific form of the shipping entry signal and the specific implementation of the shipping identification unit 307, please refer to the applicant's prior applications, which will not be elaborated here.

[0086] In this embodiment, during the shipping mode, the battery 100 stops supplying power to the system circuit 200, and at least some units of the battery protection circuit 300 are also de-energized. For example, at least one of the following units of the battery protection circuit 300—the reference voltage generation unit 301, the discharge overcurrent protection unit 302, the overcharge voltage protection unit 303, the charging overcurrent protection unit 304, and the over-discharge voltage protection unit 306—is de-energized. This can further reduce the power consumption of the battery 100 and improve its power retention time, especially for small-capacity batteries. Furthermore, in other embodiments of this application, the battery protection circuit 300 may also include other units, such as a temperature protection unit. During the shipping mode, the temperature protection unit may or may not be energized; this embodiment does not limit its operation.

[0087] Accordingly, in order to exit the shipping model, refer to Figure 2 As shown, the battery protection circuit 300 also includes a wake-up unit 305, which is a charging detection unit used to detect whether the electronic device is connected to the power source via a charger to charge the battery 300. When the electronic device is connected to the power source via a charger, the level of the system terminal VM changes, the charging detection unit detects a charging signal to charge the battery 300, and the battery protection circuit 300 automatically exits the shipping mode. In this embodiment, if the battery protection circuit 300 enters the shipping mode based on the over-discharge voltage protection unit 306 for over-discharge voltage protection of the battery 300, then when the charging detection unit detects a charging signal, the battery protection circuit 300 exits the over-discharge voltage protection of the battery 300, thereby also triggering the battery protection circuit 300 to exit the shipping mode. The charging detection circuit is an integral part of the battery protection circuit 300, and this design saves costs.

[0088] However, in some application scenarios, users may not have a charger with them. In this case, they cannot trigger the battery protection circuit to exit the shipping mode by charging, which will cause the electronic device to malfunction and result in a poor user experience.

[0089] To address the issue of the battery protection circuit failing to exit shipping mode in a timely manner due to users not carrying chargers for their electronic devices, according to... Figure 1a , Figure 1b , Figure 2As shown, the battery protection circuit 300 also includes a return shipping terminal (DTL) and a first processing unit 310. The return shipping terminal (DTL) is connected to the first processing unit 310, which is also connected to the main control unit 320. In this embodiment, when the battery protection circuit 300 is in shipping mode, the main switch unit 400 is controlled to disconnect, and the system circuit 200 is powered off. When the first processing unit 310 detects that the return shipping terminal (DTL) meets preset conditions, the first processing unit 310 outputs a return shipping enable signal, so that the main control unit 320 controls the battery protection circuit 300 to enter normal mode. In normal mode, the main switch unit 400 is turned on again, and the battery 100 resumes power supply to the system circuit 200.

[0090] Specifically, when the battery protection circuit 300 is in shipping mode, it can be triggered to enter normal mode via the return shipping terminal DTL, the main switch unit 400 resumes conduction, and the system circuit 200 is restored to power. That is, even when the electronic device is not connected to a charger, the battery protection circuit 300 can be automatically triggered to return to normal mode if the return shipping terminal DTL meets preset conditions, thus improving the user experience.

[0091] In the embodiments of this application, reference is made to Figure 1a and Figure 1b As shown, to facilitate user operation of the electronic device and change the signal of the return shipping terminal DTL, a user-controllable switch K0 can be connected between the return shipping terminal DTL of the battery protection circuit 300 and the system terminal VM. Specifically, the return shipping terminal DTL is connected to the first terminal of the switch K0, and the system terminal VM is connected to the second terminal of the switch K0. The switch K0 is an external switching element of the battery protection circuit 300. This switch K0 can be an exposed on / off switch on the outer surface of the electronic device, allowing the user to operate the switch K0 as needed to control its on / off state, thereby changing the state of the return shipping terminal DTL. As an example, when the battery protection circuit 300 is in shipping mode and the switch K0 changes from an off state to a conducting state, the first processing unit 310 can detect that the return shipping terminal DTL meets a preset condition.

[0092] Optionally, when the battery protection circuit 300 is in shipping mode, the switch control key K0 is in the off state. When the switch control key K0 is operated, changing it from the off state to the on state, the state of the return shipping terminal DTL will change, thereby triggering the first processing unit 310 to detect that the return shipping terminal DTL meets the preset conditions. At this time, the first processing unit 310 will output a return shipping enable signal, so that when the main control unit 320 receives the return shipping enable signal, it controls the battery protection circuit 300 to exit the shipping mode and enter the normal mode, restoring the power supply of the battery 100 to the system circuit 200, and the system circuit 200 returns to the normal working state.

[0093] In one embodiment of this application, when the switch control key K0 is turned on, the voltage change of the system terminal VM is small, and the voltage change of the system terminal VM alone is insufficient to cause the battery protection circuit 300 to exit the shipping mode.

[0094] For example, in this embodiment, in order to change the signal of the DTL terminal without changing the shape of the electronic device, the switch key K0 can be a function key of the electronic device, that is, reuse the original function key of the electronic device. For example, the switch key K0 is the power key of the electronic device. When the battery protection circuit 300 is in the shipping mode, the battery 100 stops supplying power to the system circuit 200, the system circuit 200 is in a power-off state, and the switch key K0 is in the off state. When the user wants to use the various functions of the electronic device, the system circuit 200 needs to be powered on first. Therefore, it is necessary to control the battery protection circuit 300 to exit the shipping mode.

[0095] When the user operates the switch control key K0, for example by pressing the switch control key K0, causing the switch control key K0 to change from the off state to the on state, the return-ship terminal DTL of the battery protection circuit 300 can be triggered to meet the preset conditions, thereby causing the first processing unit 310 to output the return-ship enable signal. Correspondingly, the main control unit 320 controls the battery protection circuit 300 to enter the normal mode according to the received return-ship enable signal, the main switch unit 400 becomes the on and on state, the system circuit 200 is restored to power supply, and the electronic device enters the normal working state.

[0096] For example, the switch control key K0 is a normally open tactile switch, which is naturally popped up in its natural state. When it is not pressed, the two ends of the key are in an open state. When the switch control key K0 is pressed and the two ends of the key become in a closed state, the first processing unit 310 detects that the return ship terminal DTL meets the preset conditions, thereby enabling the battery protection circuit 300 to enter the normal mode.

[0097] In this embodiment, in order to better understand that when the switch control key K0 changes from the off state to the on state, the first processing unit 310 will detect that the return ship terminal DTL meets the preset conditions, the following explanation is combined with the internal composition and connection relationship of the battery protection circuit 300.

[0098] Optional, Figures 3a to 3d This is a schematic diagram illustrating the working principle of the battery protection circuit provided in the first embodiment of this application. Please refer to... Figure 3a and Figure 3b As shown, when the battery protection circuit 300 is a negative lithium protection circuit, i.e., the main switch unit 400 is electrically connected between the power supply ground terminal GND and the system terminal VM, within the battery protection circuit 300, the system terminal VM is connected to the power supply terminal VDD via the first switch k1, and the reverse terminal DTL is connected to the power supply ground terminal GND via the first resistor R1. Please refer to... Figure 3c and Figure 3d As shown, when the battery protection circuit 300 is a positive lithium protection circuit, that is, when the main switch unit 400 is electrically connected between the power supply terminal VDD and the system terminal VM, inside the battery protection circuit 300, the system terminal VM is connected to the power ground terminal GND via the first switch k1, and the power supply terminal DTL is connected to the power supply terminal VDD via the first resistor R1.

[0099] In the shipping mode, the first switch k1 is turned on, and the return shipping terminal DTL and the system terminal VM are disconnected. When the return shipping terminal DTL and the system terminal VM are electrically connected, the first processing unit 310 detects that the return shipping terminal DTL meets the preset conditions.

[0100] In the embodiments of this application, to prevent the battery protection circuit 300 from automatically exiting the shipping mode after entering it, the first switch k1 is in the on state during shipping mode, and the out-of-shipment terminal DTL and the system terminal VM are disconnected. At this time, in Figure 3a and Figure 3b In the schematic diagram shown, the voltage of the system terminal VM is pulled up to the voltage of the power supply terminal VDD, and the voltage of the ship return terminal DTL is pulled down to the voltage of the power supply ground terminal GND. Figure 3c and Figure 3d In the schematic diagram shown, the voltage of the system-side VM is pulled down to the voltage of the power supply ground terminal GND, and the voltage of the ship-side DTL is pulled up to the voltage of the power supply terminal VDD.

[0101] Optionally, in order to change the state of the return shipping terminal DTL, in the embodiments of this application, during shipping mode, the return shipping terminal DTL and the system-side VM are disconnected, for example, referring to... Figures 3a to 3dAs shown, a switch K0 is connected between the return shipping terminal DTL and the system terminal VM, and the switch K0 is in the off state. Correspondingly, if the battery protection circuit 300 is to be triggered to exit the shipping mode and enter the normal mode, the return shipping terminal DTL and the system terminal VM can be electrically connected, for example, by controlling the switch K0 to be turned on, so that the branch where the return shipping terminal DTL and the system terminal VM are located can form a current path, thereby triggering a change in the signal of the return shipping terminal DTL, so that the first processing unit 310 can detect that the return shipping terminal DTL meets the preset conditions.

[0102] Optionally, in other embodiments of this application, a second resistor R2 is further connected between the system-side VM and the power supply terminal VDD or the power ground terminal GND, and the second resistor R2 is connected in series with the first switch k1. For example, in order to significantly change the signal of the return-shipping terminal DTL by electrically connecting it to the return-shipping terminal DTL, the ratio of the first resistor R1 to the second resistor R2 can be less than a preset value. For example, the preset value can be any value from 1 to 10, such as 2, 3, 4, 8, etc. This application does not limit the specific magnitude relationship between the two resistors.

[0103] As an example, in shipping mode, if the voltage of the return shipping terminal DTL meets a preset threshold condition, the first processing unit 310 detects that the return shipping terminal DTL meets the preset condition.

[0104] Continue to refer to Figures 3a to 3d As shown, in this embodiment, the first processing unit 310 includes a threshold detection branch 31A and a first voltage comparison unit CP1; wherein, the threshold detection branch 31A has its first end connected to the power supply terminal VDD, its second end connected to the power ground terminal GND, its input end connected to the ship return terminal DTL, its output end connected to the input end of the first voltage comparison unit CP1, and the output end of the first voltage comparison unit CP1 connected to the main control unit 320.

[0105] In shipping mode, if the voltage of the return shipping terminal DTL meets the first preset threshold, the threshold detection branch 31A outputs the first voltage value, and the first processing unit 310 determines whether to output the return shipping enable signal based on the comparison result of the first voltage comparison unit CP1 on the first voltage value.

[0106] It is understood that in this embodiment, the condition that the voltage of the return shipping terminal DTL meets the preset threshold includes the threshold detection branch 31A outputting a first voltage value and the first voltage comparison unit CP1 determining that the first voltage value it receives also meets the threshold requirement. That is, the first processing unit 310 outputs the return shipping enable signal only when the voltage of the return shipping terminal DTL meets the first preset threshold and the first voltage value output by the threshold detection branch 31A also meets the threshold requirement.

[0107] In one possible design, refer to Figures 3a to 3d As shown, the threshold detection branch 31A includes a first current source I0 and a branch switch transistor connected in series. The control terminal of the branch switch transistor is connected to the ship return terminal DTL, and the first connection point Pot of the first current source I0 and the branch switch transistor is connected to the input terminal of the first voltage comparison unit CP1. Accordingly, in this embodiment, when the voltage of the ship return terminal DTL meets the preset threshold, the state of the branch switch transistor changes from the first switching state to the second switching state, and the threshold detection branch 31A outputs a first voltage value through the first connection point Pot.

[0108] Understandably, based on the positional relationship between the first current source I0 and the branch switch transistor between the power supply terminal VDD and the power ground terminal GND, a suitable type of branch switch transistor can be selected to detect whether the voltage of the DTL at the return-to-ship end meets the preset threshold. Correspondingly, the first voltage value output by the threshold detection branch 31A may differ. In this case, by reasonably setting the threshold of the first voltage comparison unit CP1, it can be determined whether the DTL at the return-to-ship end meets the preset threshold condition. Optionally, the first voltage comparison unit CP1 can be implemented using a Schmitt comparator, which has a built-in first upper threshold and a first lower threshold. Optionally, based on the type of battery protection circuit 300 (positive or negative lithium protection) and the positional relationship between the first current source I0 and the branch switch transistor in the threshold detection branch 31A, the specific cases can be divided into the following four categories:

[0109] The first type: Reference Figure 3aAs shown, the battery protection circuit 300 is connected as a negative lithium protection circuit. Therefore, in shipping mode, the voltage of the system terminal VM is pulled up to the voltage of the power supply terminal VDD, and the voltage of the return shipping terminal DTL is pulled down to the voltage of the power supply ground terminal GND. In this example, the branch switch is an N-type switch N1. Its first terminal is connected to the power supply terminal VDD through the first current source I0, its second terminal is connected to the power supply ground terminal GND, and its control terminal is connected to the return shipping terminal DTL. In shipping mode, when the return shipping terminal DTL is disconnected from the system terminal VM, the voltage of the return shipping terminal DTL is low, which is less than the turn-on threshold of the branch switch. The branch switch is in the off state. Therefore, the output terminal of the threshold detection branch 31A is pulled up to the voltage of the power supply terminal VDD. At this time, the first voltage comparison unit CP1 determines that the first voltage value output by the threshold detection branch 31A does not meet the requirements. Due to the threshold condition, the first processing unit 310 does not output the ship return enable signal. When the ship return terminal DTL is electrically connected to the system terminal VM, if the second resistor R2 is not set or the set second resistor R2 is much smaller than the resistance value of the first resistor R1, a current path is formed between the power supply terminal VDD and the power ground terminal GND through the system terminal VM and the ship return terminal DTL. The voltage of the ship return terminal DTL is pulled up. When the voltage of the ship return terminal DTL is pulled up to a value greater than or equal to the opening threshold of the branch switch, the branch switch is turned on. At this time, the voltage of the first connection point Pot is pulled down (for example, pulled down to the voltage of the power ground terminal GND). That is, the threshold detection branch 31A outputs a first voltage value with a smaller value. When the first voltage comparison unit CP1 determines that the first voltage value is less than the first lower limit threshold set internally, the first processing unit 310 outputs the ship return enable signal.

[0110] The second method: Reference Figure 3b As shown, the battery protection circuit 300 is also connected as a negative lithium protection circuit, which is related to... Figure 3a The only difference lies in the connection positions of the branch switch transistor and the first current source I0. For example... Figure 3bAs shown, the branch switch is an N-type switch N1. Its first terminal is connected to the power supply terminal VDD, and its second terminal is connected to the power supply ground terminal GND through the first current source I0. Its control terminal is connected to the return shipping terminal DTL. In shipping mode, the voltage of the return shipping terminal DTL is low, which is less than the turn-on threshold of the branch switch, so the branch switch is in the off state. At this time, the output terminal of the threshold detection branch 31A is pulled down to the voltage of the power supply ground terminal GND. Correspondingly, the first voltage comparison unit CP1 determines that the first voltage value output by the threshold detection branch 31A does not meet the threshold condition, and the first processing unit 3... 10. No return shipping enable signal is output; When the return shipping terminal DTL is electrically connected to the system terminal VM, the voltage of the return shipping terminal DTL is pulled up. When the voltage of the return shipping terminal DTL is pulled up to a value greater than or equal to the opening threshold of the branch switch, the branch switch is turned on. At this time, the voltage of the first connection point Pot is pulled up (for example, pulled up to the voltage of the power supply terminal VDD). That is, the threshold detection branch 31A outputs a first voltage value with a higher value. When the first voltage comparison unit CP1 determines that the first voltage value is greater than the first upper limit threshold set internally, the first processing unit 310 outputs the return shipping enable signal.

[0111] The third type: Reference Figure 3cAs shown, the battery protection circuit 300 is connected as a positive lithium protection circuit. Therefore, in shipping mode, the voltage of the system terminal VM is pulled down to the voltage of the power supply ground terminal GND, and the voltage of the return shipping terminal DTL is pulled up to the voltage of the power supply terminal VDD. In this example, the branch switch is a P-type switch P1, whose first terminal is connected to the power supply terminal VDD through the first current source I0, its second terminal is connected to the power supply ground terminal GND, and its control terminal is connected to the return shipping terminal DTL. In shipping mode, when the return shipping terminal DTL is disconnected from the system terminal VM, the voltage of the return shipping terminal DTL is high, causing the gate-source voltage of the branch switch to be greater than the turn-on threshold of the branch switch. The branch switch is in the off-state. Therefore, the output of the threshold detection branch 31A is pulled up to the voltage of the power supply terminal VDD. Correspondingly, the first voltage comparison unit CP1 determines the first voltage output of the threshold detection branch 31A. If the voltage value does not meet the threshold condition, the first processing unit 310 will not output the ship return enable signal. When the ship return terminal DTL is electrically connected to the system terminal VM, if the second resistor R2 is not set or the set second resistor R2 is much smaller than the resistance value of the first resistor R1, a current path is formed between the power supply terminal VDD and the power ground terminal GND through the system terminal VM and the ship return terminal DTL. The voltage of the ship return terminal DTL is pulled down. When the voltage of the ship return terminal DTL is pulled down to less than or equal to the opening threshold of the branch switch, the branch switch is turned on. At this time, the voltage of the first connection point Pot is pulled down (for example, pulled down to the voltage of the power ground terminal GND). That is, the threshold detection branch 31A outputs a first voltage value with a smaller value. When the first voltage comparison unit CP1 determines that the first voltage value is less than the first lower limit threshold set internally, the first processing unit 310 outputs the ship return enable signal.

[0112] The fourth type: reference Figure 3d As shown, the battery protection circuit 300 is connected as the positive lithium protection circuit, which is connected to... Figure 3c The only difference lies in the connection positions of the branch switch transistor and the first current source I0. For example... Figure 3dAs shown, the branch switch is a P-type switch P1. Its first terminal is connected to the power supply terminal VDD, and its second terminal is connected to the power supply ground terminal GND through the first current source I0. Its control terminal is connected to the return shipping terminal DTL. In shipping mode, the voltage of the return shipping terminal DTL is high, causing the gate-source voltage of the branch switch to exceed the turn-on threshold. The branch switch is in the off-state. At this time, the output of the threshold detection branch 31A is pulled down to the voltage of the power supply ground terminal GND. Correspondingly, the first voltage comparison unit CP1 determines that the first voltage value does not meet the threshold condition, and the first processing unit 310 does not output... Output a return shipping enable signal; when the return shipping terminal DTL is electrically connected to the system terminal VM, the voltage of the return shipping terminal DTL is pulled down. When the voltage of the return shipping terminal DTL is pulled down to less than or equal to the opening threshold of the branch switch, the branch switch is turned on. At this time, the voltage of the first connection point Pot is pulled up (for example, pulled up to the voltage of the power supply terminal VDD), that is, the threshold detection branch 31A outputs a first voltage value with a higher value. When the first voltage comparison unit CP1 determines that the first voltage value is greater than the first upper limit threshold set internally, the first processing unit 310 outputs a return shipping enable signal.

[0113] In practical applications, after the battery protection circuit 300 enters the normal mode, the battery 100 resumes power supply to the system circuit 200. At the same time, the battery protection circuit 300 protects the battery 100, which will greatly increase power consumption. Therefore, if the user accidentally touches the device or external interference causes the voltage of the return terminal DTL to suddenly rise, the battery protection circuit 300 will erroneously exit the return mode, which will greatly shorten the battery 100's runtime.

[0114] To address this issue, in this embodiment, in order to reduce the problem of accidental return of the shipping mode caused by accidental touches, external interference, etc., refer to Figures 3a to 3d As shown, the first processing unit 310 includes a delay branch 31B, which is used to time the duration for which the return shipping terminal DTL meets the preset conditions. When the return shipping terminal DTL meets the preset conditions and the duration of the delay branch 31B exceeds the first preset duration, the first processing unit 310 outputs a return shipping enable signal so that the main control unit 320 controls the battery protection circuit 300 to enter the normal mode.

[0115] For example, in this embodiment, the delay branch 31B includes a timing unit 311 and a first gate logic 312. The second input terminals of the timing unit 311 and the first gate logic 312 are both connected to the output terminal of the first voltage comparison unit CP1. The second input terminal of the first gate logic 312 is connected to the output terminal of the timing unit 311. The output terminal of the first gate logic 312 is connected to the main control unit 320. The first voltage comparison unit CP1 outputs a first signal when the first voltage value output by the threshold detection branch 31A meets the threshold condition. The timing unit 311 counts the duration of the first signal, that is, it starts counting when the first voltage comparison unit CP1 outputs the first signal and stops counting when the first voltage comparison unit CP1 stops outputting the first signal. When the duration of its continuous counting reaches the preset duration threshold, the timing unit 311 outputs a timing arrival signal. When the first gate logic unit 312 receives both the timing arrival signal and the first signal at the same time, it outputs a ship unloading enable signal, that is, the first processing unit 310 outputs a ship unloading enable signal so that the main control unit 320 controls the battery protection circuit 300 to enter the normal mode, the battery 100 resumes power supply to the system circuit 200 and the battery protection circuit 300 resumes protection of the battery 100.

[0116] Optionally, the preset duration threshold set in the timing unit 311 can be determined based on the user's response time. For example, the value range of the preset duration threshold can be 30-300ms, such as 128ms. This application embodiment does not limit the specific value of the preset duration threshold, which can be set according to actual needs.

[0117] In this embodiment, by adding a delay function, the return-to-ship enable signal output by the first processing unit 310 is more accurate, avoiding the possibility of the battery protection circuit 300 mistakenly returning to ship, and effectively ensuring the battery life while ensuring the normal use of the electronic device.

[0118] Optionally, in the embodiments of this application, in the shipping mode, as long as the user operates the electronic device, causing the voltage of the return shipping terminal DTL to change to meet the first preset threshold and the first voltage value output by the threshold detection branch 31A meets the comparison threshold set in the first voltage comparison unit CP1, the first processing unit 310 can output the return shipping enable signal, thereby triggering the battery protection circuit 300 to enter the normal mode. This implementation has high detection sensitivity, and the first processing unit 310 does not need to be additionally powered, making it easy to implement. Moreover, it does not require changes to the peripheral structure of the electronic device, which can improve the user's acceptance and thus enhance the user experience.

[0119] In this embodiment, to clearly explain the specific implementation of the return-to-ship enable signal output by the first processing unit 310 triggering the main control unit 320 to control the battery protection circuit 300 to enter normal mode, the following description, in conjunction with the composition structure of the main control unit 320, explains... Figure 4 The battery protection circuit 300 shown and Figures 5a to 5e The connection position of the first processing unit 310 in the battery protection circuit 300 is shown to explain the working principle of the main control unit 320 controlling the battery protection circuit 300 to enter the normal mode.

[0120] Figure 4 This is a schematic diagram of a battery protection circuit provided in the first embodiment of this application. Figures 5a to 5e This is a schematic diagram showing the structure of the first processing unit acting on different components of the battery protection circuit. (Refer to...) Figure 4 , Figures 5a to 5e As shown in the diagram, only the components related to the shipping function are illustrated, such as the shipping terminal CTL, shipping identification unit 307, and over-discharge voltage protection unit 306. In other embodiments, the battery protection circuit 300 may also include other components, such as... Figure 2 The voltage sampling unit 308, OCV 303, OCC 304, ODC 302, wake-up unit 305, etc. shown are, for example, Figure 2 Temperature detection units, etc., not shown in the embodiments, are not limited in this application.

[0121] In this embodiment, refer to Figure 4 As shown, the main control unit 320 includes a first logic unit OR1 and a main logic unit 321. The first input terminal of the first logic unit OR1 is connected to the system terminal VM, its second input terminal is connected to the shipping identification unit 307, and its third input terminal is connected to the over-discharge voltage protection unit 306. The shipping terminal CTL is connected to the shipping identification unit 307, and the output terminal of the first logic unit OR1 is connected to the main logic unit 321. Optionally, a logic gate can also be connected between the system terminal VM and the first input terminal of the first logic unit OR1, which can be determined according to the actual scenario, and this application does not limit it.

[0122] In the shipping mode, the first input of the first logic unit OR1 is the first level signal Le1, the second input is the second level signal Le2, the third input is the third level signal Le3, and the main logic unit 321 receives the fourth level signal Le4. When the first processing unit 310 outputs the shipping reversal enable signal, at least one of the first level signal Le1, the second level signal Le2, the third level signal Le3, and the fourth level signal Le4 changes, and the main control unit 320 controls the battery protection circuit 300 to enter the normal mode.

[0123] In this embodiment, the first logic unit OR1 can be implemented by an OR gate. In other embodiments, the first logic unit OR1 can also be implemented by a NOR gate. In this case, the signal output by the first logic unit OR1 will also change accordingly. Therefore, in practical applications, it is necessary to reasonably set the signal logic relationship between the first logic unit OR1 and the main logic unit 321.

[0124] For example, when the first logic unit OR1 is implemented through an OR gate, in shipping mode, the first logic unit OR1 outputs a fourth level signal Le4=0 based on the received first level signal Le1=0, second level signal Le2=0, and third level signal Le3=0. On one hand, the fourth level signal Le4=0 can trigger the main logic unit 321 to control the main switch unit 400 to remain in the off state. On the other hand, the fourth level signal Le4=0 also acts on the shipping identification unit 307 and ODV 306, causing the shipping identification unit 307 to lock the output of the second level signal Le2=0 and the ODV 306 to lock the output of the third level signal Le3=0. In this way, when the level of VM at the system end does not change, the main control unit 320 can lock the battery protection circuit 300 in shipping mode. In this embodiment, by setting a return-to-ship terminal DTL and a first processing unit 310 for the battery protection circuit 300, the output terminal of the first processing unit 310 is connected to the main control unit 320. When the first processing unit 310 outputs a return-to-ship enable signal, it can trigger at least one of the above-mentioned first level signal Le1, second level signal Le2, third level signal Le3, and fourth level signal Le4 to change, thereby triggering the main control unit 320 to control the battery protection circuit 300 to enter the normal mode.

[0125] As an example, refer to Figure 5a As shown, the battery protection circuit 300 also includes a second logic unit OR2. The second logic unit OR2 has its first input connected to the output of the first processing unit 310, its second input connected to the system terminal VM, and its output connected to the first input of the first logic unit OR1. In this example, when the first processing unit 310 outputs a return-to-ship enable signal to the first input of the second logic unit OR2, the second logic unit OR2 outputs a fifth-level signal Le5. This fifth-level signal Le5 is different from the first-level signal Le1, thereby changing the first-level signal received by the first input of the first logic unit OR1, and consequently changing the fourth-level signal received by the main logic unit 321, thus triggering the main control unit 320 to control the battery protection circuit 300 to enter normal mode.

[0126] In this embodiment, the second logic unit OR2 is implemented through an OR gate. When the ship return enable signal (e.g., 1) output by the first processing unit 310 acts on the first input terminal of the second logic unit OR2, even if the level of the system terminal VM does not change, the second logic unit OR2 can output a fifth level signal Le5 (e.g., 1) that is different from the first level signal Le1, thereby changing the first level signal received by the first input terminal of the first logic unit OR1, and thus making the output level signal of the first logic unit OR1 become 1, that is, changing the fourth level signal received by the main logic unit 321. It can trigger the main logic unit 321 to control the main switch unit 400 to turn on and conduct. At the same time, it can also act on the ship identification unit 307 and ODV 306, thereby activating the ship identification unit 307 and ODV 306, and the battery protection circuit 300 enters the normal mode.

[0127] As another example, see Figure 5b As shown, the battery protection circuit 300 also includes a third logic unit OR3. The first input of the third logic unit OR3 is connected to the output of the first processing unit 310, its second input is connected to the output of the shipping identification unit 307, and its output is connected to the second input of the first logic unit OR1. In this example, when the first processing unit 310 outputs a shipping reversal enable signal to the first input of the third logic unit OR3, the third logic unit OR3 outputs a sixth-level signal Le6. The sixth-level signal Le6 is different from the second-level signal Le2, thereby changing the second-level signal received by the second input of the first logic unit OR1, and consequently changing the fourth-level signal received by the main logic unit 321, thus triggering the main control unit 320 to control the battery protection circuit 300 to enter normal mode.

[0128] In this embodiment, the third logic unit OR3 is implemented through an OR gate. When the shipping enable signal (e.g., 1) output by the first processing unit 310 acts on the first input terminal of the third logic unit OR3, even if the output level signal of the shipping identification unit 307 does not change, the third logic unit OR3 can output a sixth level signal Le6 (e.g., 1) that is different from the second level signal Le2, thereby changing the second level signal of the second input terminal of the first logic unit OR1, and thus making the output level signal of the first logic unit OR1 become 1. That is, it changes the fourth level signal received by the main logic unit 321, which can trigger the main logic unit 321 to control the main switch unit 400 to turn on. At the same time, it can also act on the shipping identification unit 307 and ODV 306, thereby activating the shipping identification unit 307 and ODV 306, and the battery protection circuit 300 enters the normal mode.

[0129] As another example, see Figure 5cAs shown, the battery protection circuit 300 also includes a fourth logic unit OR4. The first input terminal of the fourth logic unit OR4 is connected to the output terminal of the first processing unit 310, its second input terminal is connected to the output terminal of the over-discharge voltage protection unit 306, and its output terminal is connected to the third input terminal of the first logic unit OR1. In this example, when the first processing unit 310 outputs a reversal enable signal to the first input terminal of the fourth logic unit OR4, the fourth logic unit OR4 outputs a seventh-level signal Le7. The seventh-level signal Le7 is different from the third-level signal Le3, thereby changing the third-level signal received by the third input terminal of the first logic unit OR1, and thus changing the fourth-level signal received by the main logic unit 321, thereby triggering the main control unit 320 to control the battery protection circuit 300 to enter normal mode.

[0130] In this embodiment, the fourth logic unit OR4 is implemented through an OR gate. When the ship return enable signal (e.g., 1) output by the first processing unit 310 acts on the first input terminal of the fourth logic unit OR4, even if the output level of ODV 306 does not change, the fourth logic unit OR4 can output a seventh level signal Le7 (e.g., 1) that is different from the third level signal Le3, thereby changing the third level signal at the third input terminal of the first logic unit OR1, and thus making the output level signal of the first logic unit OR1 become 1, that is, changing the fourth level signal received by the main logic unit 321. It can trigger the main logic unit 321 to control the main switch unit 400 to turn on and conduct. At the same time, it can also act on the ship identification unit 307 and ODV 306, thereby activating the ship identification unit 307 and ODV 306, and the battery protection circuit 300 enters the normal mode.

[0131] As yet another example, see reference Figure 5d As shown, the first logic unit OR1 also includes a fourth input terminal, which is connected to the output terminal of the first processing unit 310. Therefore, when the first processing unit 310 outputs a ship return enable signal to the fourth input terminal of the first logic unit OR1, the level signal of the output terminal of the first logic unit OR1 changes, so that the fourth level signal received by the main logic unit 321 changes, thereby triggering the main control unit 320 to control the battery protection circuit 300 to enter the normal mode.

[0132] In this embodiment, the first logic unit OR1 can be implemented using an OR gate with four inputs. Thus, when the shipping enable signal (e.g., 1) output by the first processing unit 310 acts on the fourth input of the first logic unit OR1, even if the level signals of the other three inputs of the first logic unit OR1 do not change, the output level signal of the first logic unit OR1 will change, for example, become 1. This can also change the fourth level signal received by the main logic unit 321. Therefore, it can also trigger the main logic unit 321 to control the main switch unit 400 to turn on. The level signal received by the main logic unit 321 can also act on the shipping identification unit 307 and ODV 306, thereby activating the shipping identification unit 307 and ODV 306, and the battery protection circuit 300 enters the normal mode.

[0133] As another example, see [reference] Figure 5e As shown, in the battery protection circuit 300, the main control unit 320 also includes a fifth logic unit OR5. The first input terminal of the fifth logic unit OR5 is connected to the output terminal of the first processing unit 310, the second input terminal is connected to the output terminal of the first logic unit OR1, and the output terminal is connected to the main logic unit 321. In this example, when the first processing unit 310 outputs a return-to-ship enable signal to the first input terminal of the fifth logic unit OR5, the fifth logic unit OR5 outputs an eighth level signal Le8. The eighth level signal Le8 is different from the fourth level signal Le4, so that the fourth level signal received by the main logic unit 321 changes, thereby triggering the main control unit 320 to control the battery protection circuit 300 to enter the normal mode.

[0134] In this embodiment, the fifth logic unit OR5 is implemented through an OR gate. When the ship return enable signal (e.g., 1) output by the first processing unit 310 acts on the first input terminal of the fifth logic unit OR5, even if the output level signal of the first logic unit OR1 does not change, the fifth logic unit OR5 can output an eighth level signal Le8 (e.g., 1) that is different from the fourth level signal Le4. This also changes the fourth level signal received by the main logic unit 321. Therefore, it can trigger the main logic unit 321 to control the main switch unit 400 to turn on. At the same time, it can also act on the ship identification unit 307 and ODV 306, thereby activating the ship identification unit 307 and ODV 306, and the battery protection circuit 300 enters the normal mode.

[0135] In the embodiments of this application, when the first processing unit 310 can act on any node of the battery protection circuit 300 related to the return shipping mode, causing the level signal output to the main logic unit 321 to change, the main control unit 320 can be triggered to control the battery protection circuit 300 to enter the normal mode. This implementation method is simple to design, requires little modification to the battery protection circuit 300, and has low cost.

[0136] It is understood that in other embodiments of this application, the battery protection circuit 300 may not include the shipping terminal CTL and the shipping identification unit 307. In this case, the explanation will be based on the battery protection circuit 300 also including an over-discharge voltage protection unit 306. That is... Figure 6 This is a schematic diagram of another structure of the battery protection circuit provided in the first embodiment of this application. (Refer to...) Figure 6 As shown, in this embodiment, the main control unit 320 includes a sixth logic unit OR6 and a main logic unit 321. The first input terminal of the sixth logic unit OR6 is connected to the system terminal VM, its second input terminal is connected to the over-discharge voltage protection unit 306, and the output terminal of the sixth logic unit OR6 is connected to the main logic unit 321. In the shipping mode, the first input terminal of the sixth logic unit OR6 is a first level signal Le1, its second input terminal is a third level signal Le3, and the main logic unit 321 receives a fourth level signal Le4. When the first processing unit 310 outputs a shipping reversal enable signal, at least one of the first level signal Le1, the third level signal Le3, and the fourth level signal Le4 changes, and the main control unit 320 controls the battery protection circuit 300 to enter the normal mode.

[0137] In this implementation, the sixth logic unit OR6 can be an OR gate with two inputs, which are connected to the system terminal VM and the over-discharge voltage protection unit 306, respectively. Therefore, in this embodiment, when the over-discharge voltage protection unit 306 determines that the voltage of the battery 100 is lower than the over-discharge voltage protection threshold, the over-discharge voltage protection unit 306 will output an over-discharge voltage protection signal, causing the second input of the sixth logic unit OR6 to receive a second level signal. At the same time, when the first input of the sixth logic unit OR6 receives a first level signal based on the level signal of the system terminal VM, the sixth logic unit OR6 will output a fourth level signal, triggering the battery protection circuit 300 to enter the shipping mode.

[0138] Correspondingly, when the first processing unit 310 outputs the ship departure enable signal, it can also act on any one of the following: the output of the system VM, the output of the over-discharge voltage protection unit 306, the output of the sixth logic unit OR6, and the third input of the sixth logic unit OR6. Ultimately, this causes the fourth level signal received by the main logic unit 321 to change, thereby triggering the battery protection circuit 300 to exit the ship departure mode and enter the normal mode.

[0139] For details on the specific implementation of this scheme, please refer to [link / reference]. Figure 5a , Figures 5c to 5e The Chinese solution is described in detail here, and will not be repeated.

[0140] In this embodiment, the battery protection circuit 300 is fabricated on the same semiconductor substrate, i.e., on the same chip. At this time, the power supply terminal VDD is the power supply pin, the power ground terminal GND is the power ground pin, the system terminal VM is the system pin, the inbound transport terminal CTL is the inbound transport pin, and the outbound transport terminal DTL is the outbound transport pin. However, this application is not limited to this. In other embodiments of this application, the components of the battery protection circuit 300, except for the main switch unit 400, are located on the first integrated circuit chip, and the main switch unit 400 is located on the second integrated circuit chip. That is, the first integrated circuit chip is fabricated on one semiconductor substrate, and the second integrated circuit chip is fabricated on another semiconductor substrate. The first integrated circuit chip and the second integrated circuit chip can be packaged into a single product, or they can be separated; those skilled in the art can configure them according to actual needs.

[0141] In the above Figures 3a to 3d The first processing unit 310 is described in one specific implementation. It determines whether the voltage value of the DTL at the ship return end meets the preset threshold condition through the threshold detection branch 31A and the first voltage comparison unit CP1. Although this method has high sensitivity, the circuit structure is relatively complex and requires the first current source I0 and the branch switch tube, which is costly. In view of this, the embodiments of this application also provide two other implementations of the first processing unit 310, which are specifically referred to in the second and third embodiments.

[0142] Second Embodiment

[0143] Figure 7a and Figure 7b This is a schematic diagram illustrating the working principle of the battery protection circuit provided in the second embodiment of this application. This embodiment is similar to... Figures 3a to 3d The difference lies in the composition and working principle of the first processing unit 310. For details, please refer to... Figure 7a and Figure 7bIn this embodiment, the first processing unit 310 includes a second voltage comparison unit CP2; the second voltage comparison unit CP2 has its input terminal connected to the return ship transport terminal DTL, and its output terminal electrically connected to the main control unit 320.

[0144] In shipping mode, the first processing unit 310 determines whether to output a shipping enable signal based on the comparison result of the voltage of the shipping return terminal DTL by the second voltage comparison unit CP2.

[0145] In one possible design of this embodiment, the second voltage comparison unit CP2 can be implemented using a Schmitt comparator, which internally has an upper threshold and a lower threshold. Its input terminal is connected to the return shipping terminal DTL. The Schmitt comparator compares the voltage of the return shipping terminal DTL with the internal upper or lower threshold. The first processing unit 310 can determine whether to output a return shipping enable signal based on the comparison result. In this embodiment, the upper and lower thresholds set internally by the Schmitt comparator can be set or adjusted according to the resistance values ​​of the second resistor R2 connected between the system terminal VM and the power supply terminal VDD, and the first resistor R1 connected between the return shipping terminal DTL and the power ground terminal GND, so that when the switch control key K0 is turned on, the Schmitt comparator can identify the voltage change of the return shipping terminal DTL and output the comparison result.

[0146] In another possible design of this embodiment, the second voltage comparison unit CP2 is a voltage comparator with two input terminals. Its first input terminal is connected to the return shipping terminal DTL, its second input terminal is used to input the reference voltage Vref, and its output terminal is electrically connected to the main control unit 320. In this case, in shipping mode, the second voltage comparison unit CP2 determines whether the voltage of the return shipping terminal DTL and the reference voltage Vref satisfy a preset relationship. The first processing unit 310 determines whether to output a return shipping enable signal based on the comparison result of the second voltage comparison unit CP2. In this embodiment... Figure 7a and Figure 7b The following explanation uses the second voltage comparison unit CP2 as a voltage comparator with two input terminals.

[0147] As an example, in Figure 7a In the middle, the battery protection circuit 300 is a negative lithium protection circuit, that is, the main switch unit 400 is connected between the system terminal VM and the power ground terminal GND. Correspondingly, the system terminal VM is connected to the power supply terminal VDD through the first switch k1 (or the first switch k1 and the second resistor R2), and the return terminal DTL is connected to the power ground terminal GND through the first resistor R1.

[0148] Optionally, the second voltage comparison unit CP2 has a first input terminal that is inverting and a second input terminal that is outverting. Therefore, in shipping mode, the system terminal VM is disconnected from the return shipping terminal DTL, and the voltage of the return shipping terminal DTL is pulled down to the power supply ground terminal GND voltage, which is less than the reference voltage Vref. Therefore, the second voltage comparison unit CP2 outputs a low-level comparison signal. When the system terminal VM is electrically connected to the return shipping terminal DTL, the voltage of the return shipping terminal DTL is the voltage divided across the first resistor R1. If only the first switch k1 or the system terminal VM is connected to the power supply terminal VDD, the voltage will be lower than the reference voltage Vref. When the second resistor R2 connected between the two is much smaller than the first resistor R1, the voltage of the DTL terminal will be pulled up to be greater than the reference voltage Vref. Correspondingly, the second voltage comparison unit CP2 will output a high-level comparison signal. If the output terminal of the second voltage comparison unit CP2 is also connected to the main control unit 320, the delay branch 31B will determine whether the duration of the high-level comparison signal is greater than or equal to the first preset duration. If so, the first processing unit 310 will output a reversal enable signal so that the main control unit 320 controls the battery protection circuit 300 to enter the normal mode.

[0149] Optional, refer to Figure 7a As shown, the return shipping terminal DTL is also connected to the power supply terminal of the second voltage comparison unit CP2. The ground terminal of the second voltage comparison unit CP2 is connected to the power supply ground terminal GND. Therefore, when the system terminal VM and the return shipping terminal DTL are disconnected, the voltage of the return shipping terminal DTL is low, and the second voltage comparison unit CP2 does not work. When the system terminal VM and the return shipping terminal DTL are electrically connected, the voltage of the return shipping terminal DTL will be pulled up to the operating voltage of the second voltage comparison unit CP2, and the second voltage comparison unit CP2 will start working to compare the voltage of the return shipping terminal DTL with the reference voltage Vref. When it is determined that the voltage is greater than the reference voltage Vref, the corresponding comparison signal is output.

[0150] As another example, in Figure 7b In the middle, the battery protection circuit 300 is a positive lithium protection circuit, that is, the main switch unit 400 is connected between the system terminal VM and the power supply terminal VDD. Correspondingly, the system terminal VM is connected to the power ground terminal GND through the first switch k1 (or the first switch k1 and the second resistor R2), and the return terminal DTL is connected to the power supply terminal VDD through the first resistor R1.

[0151] In this example, the second voltage comparator CP2 has an inverting input at its first input and a non-inverting input at its second input. Therefore, in shipping mode, the system terminal VM is disconnected from the return shipping terminal DTL, and the voltage of the return shipping terminal DTL is pulled up to the power supply terminal VDD, which is greater than the reference voltage Vref. Thus, the second voltage comparator CP2 outputs a low-level comparison signal. When the system terminal VM is electrically connected to the return shipping terminal DTL, if only the first switch is connected between the system terminal VM and the power supply terminal VDD, or if the second resistor R2 connecting the system terminal VM and the power supply terminal VDD is far from the first switch, then... When the voltage is less than the first resistor R1, the voltage of the return terminal DTL will be pulled down to less than the reference voltage Vref. Correspondingly, the second voltage comparison unit CP2 will output a high-level comparison signal. If the output terminal of the second voltage comparison unit CP2 is connected to the main control unit 320, the delay branch 31B will determine whether the duration of the high-level comparison signal is greater than or equal to the first preset duration. If so, the first processing unit 310 will output a return enable signal so that the main control unit 320 controls the battery protection circuit 300 to enter the normal mode.

[0152] Optionally, to ensure that the second voltage comparison unit CP2 does not operate when the system-side VM and the return-to-ship transport DTL are disconnected, and that the second voltage comparison unit CP2 starts operating after the system-side VM and the return-to-ship transport DTL are electrically connected, refer to... Figure 7b As shown, a second switch k2 is connected between the power supply terminal VDD and the power supply terminal of the second voltage comparison unit CP2. The retraction terminal DTL is connected to the control terminal of the second switch k2, and the ground terminal of the second voltage comparison unit CP2 is connected to the power supply ground terminal GND. Optionally, the second switch k2 can be implemented using a P-type switching transistor. Therefore, when the system terminal VM and the retraction terminal DTL are disconnected, the voltage of the retraction terminal DTL is pulled up to the power supply terminal VDD, which acts on the control terminal of the second switch k2, putting it in the off state. The second voltage comparison unit CP2 is not powered and therefore does not work at this time. When the system terminal VM and the retraction terminal DTL are electrically connected, the voltage of the retraction terminal DTL is pulled down, the second switch k2 becomes the on state, and the power supply terminal VDD supplies power to the second voltage comparison unit CP2 through the second switch k2. The second voltage comparison unit CP2 starts working to compare the voltage of the retraction terminal DTL with the reference voltage Vref. When it is determined that the voltage is less than the reference voltage Vref, the corresponding comparison signal is output.

[0153] In this embodiment, other aspects of the battery protection circuit 300 that are not detailed here, such as the composition and implementation principle of the delay branch 31B, the main control unit 320, and the main switch unit 400 included in the first processing unit 310, can be referred to the description in the first embodiment, and will not be repeated here.

[0154] In this embodiment, the first processing unit detects whether the voltage at the return shipping end meets the preset voltage threshold through the second voltage comparison unit, and the voltage at the return shipping end is used to power the circuit, which simplifies the circuit implementation and reduces the cost.

[0155] Third Embodiment

[0156] Figure 8a and Figure 8b This is a schematic diagram illustrating the working principle of the battery protection circuit provided in the third embodiment of this application. This embodiment is similar to... Figures 3a to 3d The difference lies in the composition and working principle of the first processing unit 310. For details, please refer to... Figure 8a and Figure 8b In this embodiment, the first processing unit 310 is also connected to the system VM. In the shipping mode, when the first processing unit 310 detects that the voltage of the return shipping terminal DTL and the voltage of the system VM meet the preset conditions, the first processing unit 310 outputs the return shipping enable signal so that the main control unit 320 controls the battery protection circuit 300 to enter the normal mode.

[0157] In this embodiment, the first processing unit 310 is simultaneously connected to both the return shipping terminal DTL and the system terminal VM. In shipping mode, the first processing unit 310 simultaneously detects the voltage of the return shipping terminal DTL and the voltage of the system terminal VM, determines whether the voltage of the return shipping terminal DTL and the voltage of the system terminal VM meet a preset condition, and then determines whether to output a return shipping enable signal based on the comparison result. It can be understood that when the system terminal VM and the return shipping terminal DTL are disconnected, the voltage of the return shipping terminal DTL and the voltage of the system terminal VM do not meet the preset condition. However, when the system terminal VM and the return shipping terminal DTL are electrically connected, the voltage of the return shipping terminal DTL and the voltage of the system terminal VM will meet the preset condition, thereby causing the first processing unit 310 to output a return shipping enable signal.

[0158] Optionally, refer to the above. Figure 8a and Figure 8b As shown, the above preset conditions may include any of the following:

[0159] First: The preset conditions include that the absolute value of the difference between the voltage of the DTL at the return shipping end and the voltage of the VM at the system end is less than or equal to the first voltage threshold.

[0160] In this embodiment, referring to the description in the first embodiment, a switch control key K0 is connected between the return shipping terminal DTL and the system terminal VM. The on / off state of the switch control key K0 is used to determine whether there is an electrical connection between the return shipping terminal DTL and the system terminal VM. (Refer to...) Figure 8a and Figure 8bAs shown, when switch K0 is in the open state, the absolute value of the difference between the voltage of the return terminal DTL and the voltage of the system terminal VM is close to the battery voltage. When switch K0 is in the closed state, the absolute value of the difference between the voltage of the return terminal DTL and the voltage of the system terminal VM is the voltage drop across switch K0. Ideally, if the voltage drop across switch K0 is ignored, the absolute value of the difference between the voltage of the return terminal DTL and the voltage of the system terminal VM is close to 0. Therefore, in this embodiment, the first voltage threshold is usually less than 1V. For example, the first voltage threshold can be a value between 0.2V and 0.8V, such as 0.2V.

[0161] When the absolute value of the difference between the voltage of the return shipping terminal DTL and the voltage of the system terminal VM is less than the first voltage threshold, it is considered that the return shipping terminal DTL and the system terminal VM are electrically connected, and the first processing unit 310 outputs the return shipping enable signal according to the judgment result.

[0162] Second: The absolute value of the difference between the voltage of the DTL at the return shipping end and the voltage of the VM at the system end is the first intermediate value. The preset conditions include the ratio of the first intermediate value to the voltage of the DTL at the return shipping end or the ratio to the voltage of the VM at the system end being less than or equal to the first ratio threshold.

[0163] In this embodiment, the first processing unit 310 can calculate the absolute value of the difference between the voltage of the return shipping end DTL and the voltage of the system end VM in real time, and use it as the first intermediate value. That is, regardless of whether the battery protection circuit 300 is a negative lithium protection circuit or a positive lithium protection circuit, when only the switch control key K0 is connected between the return shipping end DTL and the system end VM and the switch control key K0 changes from the open state to the on state, the value of the first intermediate value is relatively small. Optionally, the first processing unit 310 may calculate a first ratio of the first intermediate value to the voltage of the return shipping terminal DTL, and determine whether the first ratio is less than or equal to a first ratio threshold. Alternatively, the first processing unit 310 may calculate a second ratio of the first intermediate value to the voltage of the system terminal VM, and determine whether the second ratio is less than or equal to the first ratio threshold. If it is determined that the first ratio is less than or equal to the first ratio threshold or the second ratio is less than or equal to the first ratio threshold, the first processing unit 310 determines that the voltage of the return shipping terminal DTL and the voltage of the system terminal VM meet a preset condition. Otherwise, the first processing unit 310 determines that the voltage of the return shipping terminal DTL and the voltage of the system terminal VM do not meet the preset condition.

[0164] Third: The preset conditions include the ratio of the voltage of the DTL at the return shipping end to the voltage of the VM at the system end being greater than or equal to the second ratio threshold, or the ratio of the voltage of the DTL at the return shipping end to the voltage of the VM at the system end being less than or equal to the third ratio threshold.

[0165] In this embodiment, refer to Figure 8aAs shown, when the battery protection circuit 300 is a negative lithium protection circuit, in shipping mode, the voltage of the return shipping terminal DTL is close to 0, and the voltage of the system terminal VM is close to VDD. Therefore, the ratio of the voltage of the return shipping terminal DTL to the voltage of the system terminal VM is approximately 0. When the return shipping terminal DTL is electrically connected to the system terminal VM, the voltage of the return shipping terminal DTL can be pulled up to be close to the voltage of VM, so that the ratio of the voltage of the return shipping terminal DTL to the voltage of the system terminal VM gradually increases and gradually approaches 1. Therefore, it can be assumed that the second ratio threshold is a value greater than or equal to 0.8 and less than or equal to 1. Therefore, in this embodiment, when the ratio of the voltage of the return shipping terminal DTL to the voltage of the system terminal VM is greater than or equal to the second ratio threshold, the first processing unit 310 can determine that the voltage of the return shipping terminal DTL and the voltage of the system terminal VM meet the preset conditions.

[0166] Reference Figure 8b As shown, when the battery protection circuit 300 is a positive lithium protection circuit, in shipping mode, the voltage of the return shipping terminal DTL is close to equal to VDD, and the voltage of the system terminal VM is close to equal to 0. Therefore, the ratio of the voltage of the return shipping terminal DTL to the voltage of the system terminal VM is very large. When the return shipping terminal DTL is electrically connected to the system terminal VM, the voltage of the return shipping terminal DTL can be pulled down to close to the voltage of VM, so that the ratio of the voltage of the return shipping terminal DTL to the voltage of the system terminal VM gradually decreases and gradually approaches 1. Therefore, it can be assumed that the third ratio threshold is a value greater than or equal to 1 and less than or equal to 5. Therefore, in this embodiment, when the ratio of the voltage of the return shipping terminal DTL to the voltage of the system terminal VM is less than or equal to the third ratio threshold, the first processing unit 310 can determine that the voltage of the return shipping terminal DTL and the voltage of the system terminal VM meet the preset conditions.

[0167] Optionally, the following can be implemented using the first possible method based on the aforementioned preset conditions. Figure 8a and Figure 8b The schematic diagram illustrates the working principle of the first processing unit 310. For details, please refer to... Figure 8a and Figure 8b As shown, the first processing unit 310 includes a third voltage comparison unit CP3. The first input terminal of the third voltage comparison unit CP3 is electrically connected to the return shipping end DTL, the second input terminal is electrically connected to the system end VM, and the output terminal is connected to the main control unit 320.

[0168] In the shipping mode, when the absolute value of the difference between the voltage of the return shipping terminal DTL and the voltage of the system terminal VM is less than or equal to the first voltage threshold, the third voltage comparison unit CP3 outputs the first comparison signal, and the first processing unit 310 determines whether to output the return shipping enable signal based on the first comparison signal; when the absolute value of the difference between the voltage of the return shipping terminal DTL and the voltage of the system terminal VM is greater than the first voltage threshold, the third voltage comparison unit CP3 outputs the second comparison signal, and the first comparison signal is different from the second comparison signal.

[0169] As an example, in Figure 8a In the middle, the battery protection circuit 300 is a negative lithium protection circuit. The third voltage comparison unit CP3 has a first input terminal as the positive input terminal and a second input terminal as the inverting input terminal. Therefore, in the shipping mode, the system terminal VM is disconnected from the return shipping terminal DTL. The voltage of the return shipping terminal DTL is pulled down to the power ground terminal GND voltage, while the voltage of the system terminal VM is pulled up to the power supply terminal VDD voltage. The absolute value of the difference between the voltage of the return shipping terminal DTL and the voltage of the system terminal VM is greater than the first voltage threshold. That is, the sum of the voltage of the return shipping terminal DTL and the first voltage threshold Ve is still less than the voltage of the system terminal VM. Therefore, the third voltage comparison unit CP3 outputs a second comparison signal (low level signal), and the first processing unit 310 does not output a return shipping enable signal. When the system terminal VM is electrically connected to the return shipping terminal DTL, the voltage of the return shipping terminal DTL will be pulled up to be close to the voltage of the system terminal VM. This makes the absolute value of the difference between the voltage of the return shipping terminal DTL and the voltage of the system terminal VM less than or equal to the first voltage threshold Ve, and the sum of the voltage of the return shipping terminal DTL and the first voltage threshold Ve is greater than or equal to the voltage of the system terminal VM. At this time, the third voltage comparison unit CP3 will output the first comparison signal (high level signal). Furthermore, in order to avoid the battery protection circuit 300 from accidentally returning to the shipping mode, the output terminal of the third voltage comparison unit CP3 can also be connected to the main control unit 320 via a delay branch 31B. The delay branch 31B will determine whether the duration of the first comparison signal is greater than or equal to the first preset duration. If so, the first processing unit 310 will output the return shipping enable signal so that the main control unit 320 controls the battery protection circuit 300 to enter the normal mode.

[0170] Optional, refer to Figure 8aAs shown, the return shipping terminal DTL is also connected to the power supply terminal of the third voltage comparison unit CP3. The ground terminal of the third voltage comparison unit CP3 is connected to the power supply ground terminal GND. Therefore, when the system terminal VM and the return shipping terminal DTL are disconnected, the voltage of the return shipping terminal DTL is low, and the third voltage comparison unit CP3 does not work. When the system terminal VM and the return shipping terminal DTL are electrically connected, the voltage of the return shipping terminal DTL will be pulled up to the operating voltage of the third voltage comparison unit CP3, and the third voltage comparison unit CP3 will start working to compare the absolute value of the difference between the voltage of the return shipping terminal DTL and the voltage of the system terminal VM with the first voltage threshold Ve.

[0171] As another example, in Figure 8b In this example, the battery protection circuit 300 is a positive lithium battery protection circuit. The third voltage comparison unit CP3 has an inverting input and a non-inverting input. Therefore, in the shipping mode, the voltage of the shipping terminal DTL is pulled up to the power supply terminal VDD voltage, and the voltage of the system terminal VM is pulled down to the power supply ground terminal GND voltage. The difference between the voltage of the shipping terminal DTL and the voltage of the system terminal VM is greater than the first voltage threshold Ve. That is, the difference between the voltage of the shipping terminal DTL and the first voltage threshold Ve is still greater than the voltage of the system terminal VM. Therefore, the third voltage comparison unit CP3 outputs a second comparison signal (low level signal), and the first processing unit 310 does not output a shipping enable signal. When the system terminal VM is electrically connected to the return shipping terminal DTL, the voltage of the return shipping terminal DTL will be pulled down to be close to the voltage of the system terminal VM. This makes the absolute value of the difference between the voltage of the return shipping terminal DTL and the voltage of the system terminal VM less than or equal to the first voltage threshold Ve. At this time, the third voltage comparison unit CP3 will output the first comparison signal (high level signal). Similarly, a delay branch 31B can also be connected between the output terminal of the third voltage comparison unit CP3 and the main control unit 320. The first processing unit 310 will output the return shipping enable signal only when the time for which the voltage of the return shipping terminal DTL and the voltage of the system terminal VM meet the preset conditions reaches the first preset time, so that the main control unit 320 controls the battery protection circuit 300 to enter the normal mode.

[0172] Optionally, to ensure that the third voltage comparison unit CP3 does not operate when the system-side VM and the return-to-ship transport DTL are disconnected, and that the third voltage comparison unit CP3 starts operating after the system-side VM and the return-to-ship transport DTL are electrically connected, refer to... Figure 8bAs shown, a second switch k2 is connected between the power supply terminal VDD and the power supply terminal of the third voltage comparison unit CP3. The return shipping terminal DTL is connected to the control terminal of the second switch k2, and the ground terminal of the third voltage comparison unit CP3 is connected to the power supply ground terminal GND. Optionally, the second switch k2 can be implemented using a P-type switching transistor. Therefore, when the system terminal VM and the return shipping terminal DTL are disconnected, the voltage of the return shipping terminal DTL is pulled up to the power supply terminal VDD, the second switch k2 is in the off state, and the third voltage comparison unit CP3 is not powered, so it does not work at this time. When the system terminal VM and the return shipping terminal DTL are electrically connected, the voltage of the return shipping terminal DTL is pulled down, the second switch k2 becomes the on state, and the power supply terminal VDD supplies power to the third voltage comparison unit CP3 through the second switch k2. The third voltage comparison unit CP3 starts to work to compare the absolute value of the difference between the voltage of the return shipping terminal DTL and the voltage of the system terminal VM with the first voltage threshold Ve.

[0173] In this embodiment, other aspects of the battery protection circuit 300 that are not detailed here, such as the composition and implementation principle of the delay branch 31B, the main control unit 320, and the main switch unit 400 included in the first processing unit 310, can be referred to the description in the first embodiment, and will not be repeated here.

[0174] In this embodiment, the first processing unit uses a third voltage comparison unit to detect whether the voltage at the return shipping end and the voltage at the system end meet preset conditions. Furthermore, the operating state of the third voltage comparison unit is controlled based on the voltage at the return shipping end, which simplifies the circuit implementation and reduces costs.

[0175] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. Furthermore, the specific names of each functional unit and module are only for easy distinction and are not intended to limit the scope of protection of this application.

[0176] It should be understood that "a plurality of" as used herein refers to two or more. Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0177] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0178] The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Therefore, any equivalent variations made in accordance with the claims of this application shall still fall within the scope of this application.

Claims

1. A battery protection circuit for a controllable return shipping mode, characterized in that, include: The system includes a power supply terminal, a power ground terminal, a system terminal, a main control unit, and a main switch unit. The power supply terminal is used to connect to the positive terminal of the battery, and the power ground terminal is used to connect to the negative terminal of the battery. The main control unit is electrically connected to the control terminal of the main switch unit. The first terminal of the main switch unit is connected to the power supply terminal or the power ground terminal, and its second terminal is connected to the system circuit via the system terminal. The system includes a return shipping terminal and a first processing unit, wherein the return shipping terminal is connected to the first processing unit, and the first processing unit is also connected to the main control unit. The battery protection circuit operates in two modes: a shipping mode and a normal mode. In the shipping mode, the main switch unit is disconnected to stop the battery from supplying power to the system circuit. When the battery protection circuit is in the shipping mode and the first processing unit detects that the return shipping end meets the preset conditions, the first processing unit outputs a return shipping enable signal to enable the main control unit to control the battery protection circuit to enter the normal mode. In the normal mode, the main switch unit is turned on to allow the battery to supply power to the system circuit.

2. The battery protection circuit according to claim 1, characterized in that, In shipping mode, if the voltage at the return shipping terminal meets a preset threshold condition, the first processing unit detects that the return shipping terminal meets the preset condition.

3. The battery protection circuit according to claim 2, characterized in that, The first processing unit includes a threshold detection branch and a first voltage comparison unit; The threshold detection branch has its first end connected to the power supply terminal, its second end connected to the power ground terminal, its input terminal connected to the ship return terminal, its output terminal connected to the input terminal of the first voltage comparison unit, and the output terminal of the first voltage comparison unit connected to the main control unit. In shipping mode, if the voltage at the return shipping end meets the first preset threshold, the threshold detection branch outputs the first voltage value, and the first processing unit determines whether to output the return shipping enable signal based on the comparison result of the first voltage value by the first voltage comparison unit.

4. The battery protection circuit according to claim 3, characterized in that, The threshold detection branch includes a first current source and a branch switch connected in series. The control terminal of the branch switch is connected to the ship return end, and the first connection point of the first current source and the branch switch is connected to the input terminal of the first voltage comparison unit. When the voltage at the return shipping end meets a preset threshold, the state of the branch switch tube changes from a first switch state to a second switch state, and the threshold detection branch outputs a first voltage value through the first connection point.

5. The battery protection circuit according to claim 2, characterized in that, The first processing unit includes a second voltage comparison unit; the second voltage comparison unit has its input terminal connected to the return shipping end and its output terminal electrically connected to the main control unit. In shipping mode, the first processing unit determines whether to output a shipping return enable signal based on the comparison result of the voltage of the return shipping terminal by the second voltage comparison unit.

6. The battery protection circuit according to claim 1, characterized in that, The first processing unit is also connected to the system terminal. In shipping mode, when the first processing unit detects that the voltage of the return shipping terminal and the voltage of the system terminal meet preset conditions, the first processing unit outputs a return shipping enable signal so that the main control unit controls the battery protection circuit to enter normal mode.

7. The battery protection circuit according to claim 6, characterized in that, The preset conditions include that the absolute value of the difference between the voltage at the return shipping end and the voltage at the system end is less than or equal to a first voltage threshold; or, The absolute value of the difference between the voltage at the return shipping end and the voltage at the system end is a first intermediate value. The preset condition includes the ratio of the first intermediate value to the voltage at the return shipping end or to the voltage at the system end being less than or equal to a first ratio threshold; or, The preset conditions include the ratio of the voltage at the return shipping end to the voltage at the system end being greater than or equal to a second ratio threshold, or the ratio of the voltage at the return shipping end to the voltage at the system end being less than or equal to a third ratio threshold.

8. The battery protection circuit according to claim 6, characterized in that, The first processing unit includes a third voltage comparison unit, wherein the first input terminal of the third voltage comparison unit is electrically connected to the ship return terminal, the second input terminal is electrically connected to the system terminal, and the output terminal is connected to the main control unit. In shipping mode, when the absolute value of the difference between the voltage at the return shipping end and the voltage at the system end is less than or equal to a first voltage threshold, the third voltage comparison unit outputs a first comparison signal, and the first processing unit determines whether to output a return shipping enable signal based on the first comparison signal. When the absolute value of the difference between the voltage at the return shipping end and the voltage at the system end is greater than the first voltage threshold, the third voltage comparison unit outputs a second comparison signal, wherein the first comparison signal is different from the second comparison signal.

9. The battery protection circuit according to any one of claims 1-8, characterized in that, The first processing unit includes a delay branch, which is used to time the duration for which the return shipping end meets the preset conditions. When the return shipping end meets the preset conditions and the duration of the delay branch is greater than a first preset duration, the first processing unit outputs a return shipping enable signal so that the main control unit controls the battery protection circuit to enter the normal mode.

10. The battery protection circuit according to any one of claims 1-8, characterized in that, The return shipping end is used to connect to the first end of the switch control key, and the system end is used to connect to the second end of the switch control key; When the battery protection circuit is in shipping mode and the switch control key changes from the off state to the on state, the first processing unit detects that the return shipping end meets the preset conditions.

11. The battery protection circuit according to any one of claims 1-8, characterized in that, If the main switch unit is electrically connected between the power supply ground terminal and the system terminal, then the system terminal is connected to the power supply terminal via the first switch, and the ship retraction terminal is connected to the power supply ground terminal via the first resistor; or, if the main switch unit is electrically connected between the power supply terminal and the system terminal, then the system terminal is connected to the power supply ground terminal via the first switch, and the ship retraction terminal is connected to the power supply terminal via the first resistor. In shipping mode, the first switch is turned on, and the return shipping end and the system end are disconnected. When the return shipping end and the system end are electrically connected, the first processing unit detects that the return shipping end meets the preset conditions.

12. The battery protection circuit according to any one of claims 1-8, characterized in that, The battery protection circuit also includes a shipping terminal, a shipping identification unit, and an over-discharge voltage protection unit. The main control unit includes a first logic unit and a main logic unit. The first input terminal of the first logic unit is connected to the system terminal, its second input terminal is connected to the shipping identification unit, and its third input terminal is connected to the over-discharge voltage protection unit. The shipping terminal is connected to the shipping identification unit, and the output terminal of the first logic unit is connected to the main logic unit. In shipping mode, the first input terminal of the first logic unit is a first level signal, its second input terminal is a second level signal, its third input terminal is a third level signal, and the main logic unit receives a fourth level signal. When the first processing unit outputs a ship return enable signal, at least one of the first level signal, the second level signal, the third level signal, and the fourth level signal changes, and the main control unit controls the battery protection circuit to enter normal mode.

13. The battery protection circuit according to claim 12, characterized in that, It also includes a second logic unit, wherein the first input terminal of the second logic unit is connected to the output terminal of the first processing unit, the second input terminal is connected to the system terminal, and the output terminal is connected to the first input terminal of the first logic unit; When the first processing unit outputs a ship return enable signal to the first input terminal of the second logic unit, the second logic unit outputs a fifth level signal, which is different from the first level signal, to change the first level signal received by the first input terminal of the first logic unit, thereby changing the fourth level signal received by the main logic unit, so as to trigger the main control unit to control the battery protection circuit to enter the normal mode.

14. The battery protection circuit according to claim 12, characterized in that, It also includes a third logic unit, wherein the first input terminal of the third logic unit is connected to the output terminal of the first processing unit, the second input terminal is connected to the output terminal of the shipping identification unit, and the output terminal is connected to the second input terminal of the first logic unit; When the first processing unit outputs a ship return enable signal to the first input terminal of the third logic unit, the third logic unit outputs a sixth level signal, which is different from the second level signal, to change the second level signal received by the second input terminal of the first logic unit, thereby changing the fourth level signal received by the main logic unit, so as to trigger the main control unit to control the battery protection circuit to enter the normal mode.

15. The battery protection circuit according to claim 12, characterized in that, It also includes a fourth logic unit, wherein the first input terminal of the fourth logic unit is connected to the output terminal of the first processing unit, the second input terminal is connected to the output terminal of the over-discharge voltage protection unit, and the output terminal is connected to the third input terminal of the first logic unit. When the first processing unit outputs a ship return enable signal to the first input terminal of the fourth logic unit, the fourth logic unit outputs a seventh level signal, which is different from the third level signal, to change the third level signal received by the third input terminal of the first logic unit, thereby changing the fourth level signal received by the main logic unit, so as to trigger the main control unit to control the battery protection circuit to enter the normal mode.

16. The battery protection circuit according to claim 12, characterized in that, The first logic unit further includes a fourth input terminal, which is connected to the output terminal of the first processing unit; When the first processing unit outputs a return-to-ship enable signal to the fourth input terminal of the first logic unit, the level signal at the output terminal of the first logic unit changes, thereby changing the fourth level signal received by the main logic unit, which in turn triggers the main control unit to control the battery protection circuit to enter normal mode.

17. The battery protection circuit according to claim 12, characterized in that, The main control unit further includes a fifth logic unit, wherein the first input terminal of the fifth logic unit is connected to the output terminal of the first processing unit, the second input terminal is connected to the output terminal of the first logic unit, and the output terminal is connected to the main logic unit. When the first processing unit outputs a ship return enable signal to the first input terminal of the fifth logic unit, the fifth logic unit outputs an eighth level signal to change the fourth level signal received by the main logic unit, thereby triggering the main control unit to control the battery protection circuit to enter normal mode.

18. The battery protection circuit according to any one of claims 1-8, characterized in that, The battery protection circuit also includes an over-discharge voltage protection unit. The main control unit includes a sixth logic unit and a main logic unit. The first input terminal of the sixth logic unit is connected to the system terminal, its second input terminal is connected to the over-discharge voltage protection unit, and the output terminal of the sixth logic unit is connected to the main logic unit. In shipping mode, the first input of the sixth logic unit is a first-level signal, its second input is a third-level signal, and the main logic unit receives a fourth-level signal. When the first processing unit outputs a shipping reversal enable signal, at least one of the first-level signal, the third-level signal, and the fourth-level signal changes, and the main control unit controls the battery protection circuit to enter normal mode.

19. The battery protection circuit according to any one of claims 1-8, characterized in that, The battery protection circuit is located on the same chip; or... The battery protection circuit, excluding the main switch unit, has its components located on one chip, while the main switch unit is located on another chip.

20. A battery assembly, characterized in that, include: Battery; The battery protection circuit as described in any one of claims 1-19, wherein the battery protection circuit is connected to the battery.

21. An electronic device, characterized in that, include: The battery protection circuit as described in any one of claims 1-19 or the battery assembly as described in claim 20; The system circuit is connected to the battery via the main switching unit of the battery protection circuit; A switch control key, the two ends of which are electrically connected to the return end and the system end of the battery protection circuit, respectively. In the shipping mode, if the switch control key changes from the off state to the on state, the battery protection circuit enters the normal mode, and in the normal mode, the battery supplies power to the system circuit.

22. The electronic device according to claim 21, characterized in that, The system circuit includes a processor and a load circuit. The processor is used to detect the working status of the load circuit. When it detects that the load circuit has stopped working and the duration of the stop working is longer than a preset duration, it outputs a shipping entry signal to the battery protection circuit so that the battery protection circuit enters the shipping mode.

23. The electronic device according to claim 21 or 22, characterized in that, The switch control key is the function control key of the electronic device.

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