Overvoltage protection circuit and intelligent device

Abstract

The application provides an overvoltage protection circuit and a smart device, wherein the overvoltage protection circuit comprises: a control switch, a first end of the control switch is connected with a battery for transmitting voltage; a control chip is arranged between the control switch and the battery, the control chip acquires a battery voltage signal, and generates a control signal according to the battery voltage; and a protection chip, an output end of the protection chip is connected with the control switch, an input end of the protection chip is connected with the control chip and receives the control signal, and the protection chip outputs voltage according to the control signal for controlling the on-off state of the control switch. In the above manner, the charging speed is ensured, the voltage of the battery is monitored, the protection chip can timely control the control switch connected to be turned on or turned off to close the loop, the battery is prevented from being damaged due to overvoltage, the safety of the battery is ensured, problems such as battery bulging, overshooting or power shortage are avoided, and the endurance and service life of the battery are improved.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and in particular to an overvoltage protection circuit and a smart device. Background Technology

[0002] With the advancement of technology, electricity is widely used in fields such as smart devices and electric vehicles. In today's fast-paced life, in order to meet users' demands for charging speed, especially by increasing charging power or optimizing charging protocols, while making our lives more convenient, some hidden dangers have also arisen that deserve our consideration. Problems such as battery bulging and explosions inevitably occur from time to time, posing threats to our lives and property.

[0003] Battery safety is of paramount importance in today's society. To ensure the safe and stable operation of batteries, implementing certain protective measures is of great significance in improving battery reliability and safety. Summary of the Invention

[0004] This application provides an overvoltage protection circuit and a smart device to achieve overvoltage protection of the battery, thereby ensuring battery safety.

[0005] To solve the above-mentioned technical problems, the first aspect of this application provides an overvoltage protection circuit.

[0006] The overvoltage protection circuit includes: a control switch, the first end of which is connected to the battery for transmitting voltage; a control chip, which is located between the control switch and the battery, and acquires the battery voltage signal to generate a control signal based on the battery voltage; and a protection chip, the output end of which is connected to the control switch, and the input end of which is connected to the control chip and receives the control signal. The protection chip outputs a voltage based on the control signal to control the conduction state of its control switch.

[0007] The second terminal of the control switch is connected to a voltage source, transmitting the voltage from the voltage source to the control chip; the control chip then transmits the voltage from the voltage source to the battery to charge it.

[0008] The control chip converts the voltage source voltage into a charging voltage, transmits the charging voltage to charge the battery, and generates a first control signal based on the battery voltage and / or the charging voltage. The protection chip receives the first control signal from the control chip and outputs a voltage based on the first control signal to control the conduction state of its control switch.

[0009] The control chip confirms that the battery voltage is greater than the rated battery voltage, and / or confirms that the battery voltage is greater than the rated charging voltage, and outputs a low-level first control signal; the protection chip outputs a low-level voltage based on the low-level first control signal to turn off the control switch.

[0010] The control chip converts the voltage source voltage into a charging voltage with a constant magnitude.

[0011] The control chip confirms that the charging voltage is greater than the rated charging voltage and outputs a low-level first control signal; the protection chip outputs a low-level voltage based on the low-level first control signal to turn off the control switch.

[0012] The control chip is connected to the voltage source and generates a first control signal and a second control signal based on the voltage of the voltage source. The protection chip outputs a high-level voltage based on the first and second control signals, which are both high-level voltages, and turns on the control switch.

[0013] The control chip includes a charging chip and a processing chip that are interconnected. The charging chip is connected to a control switch, and the processing chip is connected to a protection chip. The charging chip converts the voltage source voltage into a charging voltage, transmits the charging voltage to charge the battery, and generates a first control signal based on the battery voltage and / or the charging voltage. The processing chip receives the first control signal from the charging chip and generates a third control signal based on the first control signal. The protection chip receives the third control signal from the processing chip and outputs a voltage based on the third control signal to control the conduction state of its control switch.

[0014] The control switch has a first terminal connected to an external device; the control chip transmits battery voltage to the control switch, which then powers the external device; the control chip connects to the external device and generates a first control signal and a second control signal based on the device signal from the external device; the protection chip outputs a high-level voltage based on the first and second control signals, which are both high-level voltages, to turn on the control switch.

[0015] To address the aforementioned technical problems, a second aspect of this application provides an intelligent device, comprising: a battery; an overvoltage protection circuit, the overvoltage protection circuit including a control switch, a control chip, and a protection chip; a first terminal of the control switch connected to the battery for transmitting voltage; a control chip disposed between the control switch and the battery, the control chip acquiring the battery voltage signal and generating a control signal based on the battery voltage; an output terminal of the protection chip connected to the control switch, an input terminal connected to the control chip and receiving the control signal, and the protection chip outputting a voltage based on the control signal to control the conduction state of its control switch.

[0016] Unlike existing technologies, this application provides an overvoltage protection circuit and intelligent device that, while ensuring charging speed, monitors the battery voltage through a control chip. The protection chip can promptly control the connected control switch to turn the circuit on or off, preventing battery damage due to overvoltage, ensuring battery safety, avoiding problems such as battery bulging, overcharging, or depletion, and improving battery range and lifespan. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the first embodiment of the overvoltage protection circuit of this application;

[0018] Figure 2 This is the second embodiment of the overvoltage protection circuit of this application.

[0019] Figure 3 This is a schematic diagram of another specific embodiment of the overvoltage protection circuit of this application;

[0020] Figure 4 This is a schematic diagram of another specific embodiment of the overvoltage protection circuit of this application;

[0021] Figure 5 This is a schematic diagram of the third embodiment of the overvoltage protection circuit of this application;

[0022] Figure 6 This is a schematic diagram of the structure of the fourth embodiment of the overvoltage protection circuit of this application;

[0023] Figure 7 This is a schematic diagram of the structure of one embodiment of a smart device according to this application;

[0024] Figure 8 This is a schematic diagram of another embodiment of a smart device according to this application. Detailed Implementation

[0025] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0026] All overvoltage protection circuit diagrams and smart device diagrams in this application are circuit logic illustrations; the specific connection structures are based on actual production structures. In the following description, specific details such as particular system structures, interfaces, and technologies are presented for illustrative purposes rather than limiting, in order to provide a thorough understanding of this application.

[0027] This application first provides an overvoltage protection circuit that can be connected to a battery to provide overvoltage protection for the battery. Please refer to [link to relevant documentation]. Figure 1 , Figure 1 This is a schematic diagram of the structure of the first embodiment of the overvoltage protection circuit of this application.

[0028] The overvoltage protection circuit 10 includes: a control switch 101, the first end of which is connected to the battery 11 for transmitting voltage; and a control chip 102, which is disposed between the control switch 101 and the battery 11, and the control chip 102 acquires the battery 11 voltage signal and generates a control signal based on the battery 11 voltage.

[0029] During the charging and discharging process of battery 11, the voltage of battery 11 is directly monitored by control chip 102, and control signals are generated. The state of battery 11 can be monitored by the voltage of battery 11, and the conduction control of the input and output of battery 11 can be controlled by control switch 101. When the detected voltage exceeds the set threshold, the corresponding control signal is output to perform overcurrent protection. The control signal generated by control chip 102 can be an electrical signal, or in an optional embodiment, a voltage signal.

[0030] The protection chip 103 has its output terminal connected to the control switch 101 and its input terminal connected to the control chip 102 to receive control signals. The protection chip 103 outputs voltage according to the control signals to control the conduction state of its control switch 101.

[0031] The protection chip 103 directly controls the conduction state of the control switch 101 set between the voltage source 12 and the control chip 102 according to the corresponding voltage output by the control signal, cuts off the current passing through the control switch 101, thereby realizing overvoltage protection of the battery 11, and can also effectively protect the control chip 102 and prevent the control chip 102 from overload.

[0032] Please refer to Figure 2 , Figure 2 This is a schematic diagram of a specific embodiment of the second implementation of the overvoltage protection circuit of this application.

[0033] In one alternative embodiment, the second terminal of the control switch 101 is connected to the voltage source 12, transmitting the voltage from the voltage source to the control chip 102; the control chip 102 transmits the voltage from the voltage source 12 to the battery 11 to charge the battery 11.

[0034] In one specific embodiment, the control switch 101 is an N-type field-effect transistor, but in other embodiments it can also be an insulated gate bipolar transistor, a PNP transistor, or other suitable components.

[0035] The control chip 102 can be a charging chip 1021, which converts the DC or AC power from the voltage source 12 into DC power. The control chip 102 converts the voltage source voltage into a charging voltage, transmits the charging voltage to charge the battery 11, and generates a first control signal based on the battery 11 voltage and / or the charging voltage. The protection chip 103 receives the first control signal from the control chip 102 and outputs a voltage based on the first control signal to control the conduction state of its control switch 101.

[0036] During the charging process of battery 11, in order to overcome the resistance of the electrochemical reaction, the charging voltage needs to be higher than the battery 11 voltage, which can easily lead to overheating and high voltage, posing a certain safety hazard. Therefore, during the charging process, the control chip 102 monitors the voltage signal of battery 11 and / or the charging voltage, and provides a control signal for overvoltage protection.

[0037] In one alternative implementation, the control chip 102 confirms that the battery voltage 11 is greater than the rated battery voltage 11, and / or confirms that the battery voltage 11 is greater than the rated charging voltage, and outputs a low-level first control signal; the protection chip 103 outputs a low-level voltage according to the low-level first control signal to turn off the control switch 101.

[0038] The rated charging voltage can be set according to the capacity of battery 11 and the charging protocol. The control chip 102 ensures that the control switch 101 can be enabled to open when battery 11 is charging normally, and enabled to close in case of over-discharge of battery 11.

[0039] In other embodiments, the control chip 102 can also ensure, through control signals, that the overvoltage protection circuit 10 and the battery 11 are enabled and disabled when the battery 11 is not charging or in a power-off state, thereby ensuring the normal operation of the overvoltage protection circuit 10 and the battery 11.

[0040] Figure 3 This is a schematic diagram of another specific embodiment of the overvoltage protection circuit of this application;

[0041] In one alternative implementation, the control chip 102 converts the voltage source voltage into a charging voltage with a constant magnitude.

[0042] By charging the battery 11 with a constant charging voltage, the charging speed and efficiency can be guaranteed. The overvoltage protection circuit 10 can ensure the safety of the battery 11 without reducing the charging voltage or sacrificing the capacity of the battery 11.

[0043] In one alternative implementation, the control chip 102 confirms that the charging voltage is greater than the rated charging voltage and outputs a low-level first control signal; the protection chip 103 outputs a low-level voltage according to the low-level first control signal to turn off the control switch 101.

[0044] In one specific embodiment, VBUS is the voltage source voltage, VBAT is the charging voltage, and Vcell is the battery voltage. The voltage source voltage VBUS enters the control switch 101 at the source side and is connected to the control chip 102 at the drain, and converts the voltage source voltage VBUS into the charging voltage VBAT to power the battery 11.

[0045] Because there is impedance in the battery 11 and the charging circuit or overvoltage protection circuit 10, the charging voltage will be higher than the battery 11 voltage. At the same time, due to the high power current during charging, the charging voltage input to the battery 11 may be much higher than an overvoltage protection threshold of the battery 11.

[0046] Based on this potential hazard, when the charging voltage VBAT is greater than the rated charging voltage, the control chip 102 can determine to further detect the battery voltage 11. When the battery voltage Vcell is greater than or equal to the rated battery voltage and greater than the rated charging voltage, a low-level first control signal is generated, and the corresponding output voltage of the protection chip 103 is low, causing the control switch 101 to close, thereby achieving overvoltage protection and triggering an overvoltage warning.

[0047] Please refer to Figure 4 , Figure 4 This is a schematic diagram of another specific embodiment of the overvoltage protection circuit of this application.

[0048] In one optional embodiment, the control chip 102 is connected to the voltage source 12, and the control chip 102 generates a first control signal and a second control signal according to the voltage of the voltage source; the protection chip 103 outputs a high-level voltage according to the first control signal and the second control signal which are high-level voltages, and turns on the control switch 101.

[0049] When the control switch 101 is not turned on, the voltage source voltage VBUS is connected to the VAC pin of the control chip 102 through the source side of the control switch 101 and the voltage source 12, thereby obtaining a signal that indicates whether the voltage source voltage is input.

[0050] When the control chip 102 detects a voltage input from a voltage source, it outputs a high-level first control signal and a second control signal to turn on the control switch 101 and convert the voltage source voltage VBUS into a charging voltage VBAT to power the battery 11. The second control signal indicates the presence of a voltage source 12 input, and the first control signal indicates the start of charging.

[0051] If the control chip 102 detects that the voltage source voltage VBUS is higher than the rated voltage source voltage, it can also issue a warning and will not generate a high-level first control signal and second control signal on the conduction control switch 101, thus ensuring the safety of the control chip 102 and the battery 11.

[0052] The control chip 102 obtains the battery 11 voltage Vcell through the VBATT_CONN_N and VBATT_CONN_P signals. When the charging voltage VBAT is greater than the rated charging voltage, the control chip 102 determines to further detect the battery 11 voltage. When the battery 11 voltage Vcell is greater than or equal to the rated battery 11 voltage and greater than the rated charging voltage, a low-level first control signal is generated and an overvoltage warning is triggered.

[0053] In an optional embodiment, the protection chip 103 can be an AND gate chip that receives a first control signal transmitted by the control chip 102 through the EN pin and a second control signal transmitted by the control chip 102 through the VIN pin. The protection chip 103 receives the first control signal at a high level and outputs a high-level voltage when the second control signal is high. When the first control signal changes from a high level to a low level due to overvoltage protection, the voltage output by the protection chip 103 is low, causing the control switch 101 to close, thereby achieving overvoltage protection.

[0054] In an optional embodiment, if the battery 11 is not fully engaged, the impedance of the battery 11 is too high, resulting in a larger voltage difference between the charging voltage and the battery 11 voltage. The charging voltage VBAT is too high and is likely to exceed the rated charging voltage. The battery 11 can also be protected by the overvoltage protection circuit 10 of this application.

[0055] Please refer to Figure 5 , Figure 5 This is a schematic diagram of the third embodiment of the overvoltage protection circuit of this application.

[0056] In one optional embodiment, the control chip 102 includes a charging chip 1021 and a processing chip 1022 connected to each other. The charging chip 1021 is connected to the control switch 101, and the processing chip 1022 is connected to the protection chip 103. The charging chip 1021 converts the voltage source voltage into a charging voltage, transmits the charging voltage to charge the battery 11, and generates a first control signal based on the battery 11 voltage and / or the charging voltage. The processing chip 1022 receives the first control signal from the charging chip 1021 and generates a third control signal based on the first control signal. The protection chip 103 receives the third control signal from its processing chip 1022 and outputs a voltage based on the third control signal to control the conduction state of its control switch 101.

[0057] The charging chip 1021 can be a charge pump, and the processing chip 1022 can be the CPU (Central Processing Unit) of the smart device 14. In addition to generating a third control signal, the processing chip 1022 can also generate other control signals according to the first control signal to ensure that the normal operation of other components or circuits in the device will not be affected by the overvoltage of the battery 11 during charging or overvoltage protection.

[0058] In one specific embodiment, the charging chip 1021 includes a VBUS pin to receive voltage from a voltage source, a VBUS pin to output charging voltage, a VAC pin to monitor the input of voltage source 12, and an SCL pin and an SDA pin connected to the processing chip 1022.

[0059] When charging begins, the SCL and SDA pins of the charging chip send a first control signal to the processing chip 1022. After receiving the signal, the SCL and SDA pins of the processing chip 1022 generate a third control signal through the ENIT_1 pin and send it to the protection chip 103. Meanwhile, the OVP_GATE pin of the control chip 102 generates a second control signal and sends it to the protection chip 103. When the overvoltage protection of the control chip 102 is triggered, the third control signal sent by the ENIT_1 pin changes from a high level to a low level, and the voltage output by the protection chip 103 becomes low, causing the control switch 101 to close, thus achieving overvoltage protection.

[0060] Please refer to Figure 6 , Figure 6 This is a schematic diagram of the fourth embodiment of the overvoltage protection circuit of this application.

[0061] In one alternative implementation, the first end of the control switch 101 is connected to the external device 13; the control chip 102 transmits the voltage of the battery 11 to the control switch 101, thereby powering the external device 13 through the control switch 101.

[0062] When the smart device 14 uses the OTG (USB On-The-Go) function, the control switch 101 needs to be turned on, and the battery 11 will supply power to support the normal operation of the connected external devices 13, such as mobile storage disks, mice, keyboards, etc.

[0063] In one optional implementation, the control chip 102 is connected to the external device 13 and generates a first control signal and a second control signal based on the device signal of the external device 13; the protection chip 103 outputs a high-level voltage according to the first control signal and the second control signal which are high-level voltages, and turns on the control switch 101.

[0064] When the control chip 102 is connected to the external device 13, the OVP_GATE pin of the control chip 102 will detect that the voltage of the external device 13 is lower than the voltage threshold for external power supply, and generate the first control signal and the second control signal to turn on the control switch 101 and start external power supply.

[0065] The overvoltage protection circuit provided in the above embodiments can detect the charging voltage and battery voltage, and control the conduction state of its control switch to perform overvoltage protection in a timely manner, effectively preventing battery damage due to overvoltage, ensuring battery safety, avoiding problems such as battery bulging, overcharging or depletion, protecting battery performance, improving battery range and lifespan, and improving circuit stability and safety. It can be used in overvoltage protection of lithium batteries and other battery power supplies, and has a very wide range of applications.

[0066] To address the aforementioned technical problems, a second aspect of this application provides an intelligent device, please refer to... Figure 7 , Figure 7 This is a schematic diagram of one embodiment of a smart device according to this application.

[0067] The smart device 14 includes: a battery 11; an overvoltage protection circuit 10, which includes a control switch 101, a control chip 102, and a protection chip 103; the first end of the control switch 101 is connected to the battery 11 for transmitting voltage; the control chip 102 is disposed between the control switch 101 and the battery 11, and the control chip 102 acquires the voltage signal of the battery 11 and generates a control signal based on the voltage of the battery 11; the output end of the protection chip 103 is connected to the control switch 101, and the input end is connected to the control chip 102 and receives the control signal. The protection chip 103 outputs a voltage based on the control signal to control the conduction state of its control switch 101.

[0068] During the charging and discharging process of the smart device 14, the voltage of the battery 11 is directly monitored by the control chip 102, and a control signal is generated. The battery 11 status can be monitored by the battery voltage, and the input and output of the battery 11 can be controlled by the control switch 101. When the detected voltage exceeds the set threshold, the corresponding control signal is output to perform overcurrent protection. The control signal generated by the control chip 102 can be an electrical signal, or in an optional embodiment, a voltage signal.

[0069] The protection chip 103 has its output terminal connected to the control switch 101 and its input terminal connected to the control chip 102 to receive control signals. The protection chip 103 outputs voltage according to the control signals to control the conduction state of its control switch 101.

[0070] The protection chip 103 directly controls the conduction state of the control switch 101 set between the voltage source 12 and the control chip 102 according to the corresponding voltage output by the control signal, cuts off the current passing through the control switch 101, thereby realizing overvoltage protection of the battery 11, and can also effectively protect the control chip 102 and prevent the control chip 102 from overload.

[0071] Figure 8 This is a schematic diagram of another embodiment of a smart device according to this application. A detailed description of the overvoltage protection circuit 10 can be found in [reference needed]. Figure 2 , Figure 3 or Figure 5 The structural description of one embodiment or another embodiment of the overvoltage protection circuit of this application will not be repeated here.

[0072] In one alternative embodiment, the second terminal of the control switch 101 is connected to the voltage source 12, transmitting the voltage from the voltage source to the control chip 102; the control chip 102 transmits the voltage from the voltage source 12 to the battery 11 to charge the battery 11.

[0073] In one specific embodiment, the control switch 101 is an N-type field-effect transistor, but in other embodiments it can also be an insulated gate bipolar transistor, a PNP transistor, or other suitable components.

[0074] The control chip 102 can be a charging chip 1021, which converts the DC or AC power from the voltage source 12 into DC power. The control chip 102 converts the voltage source voltage into a charging voltage, transmits the charging voltage to charge the battery 11, and generates a first control signal based on the battery 11 voltage and / or the charging voltage. The protection chip 103 receives the first control signal from the control chip 102 and outputs a voltage based on the first control signal to control the conduction state of its control switch 101.

[0075] During the charging process of battery 11, in order to overcome the resistance of the electrochemical reaction, the charging voltage needs to be higher than the battery 11 voltage, which can easily lead to overheating and high voltage, posing a certain safety hazard. Therefore, during the charging process, the control chip 102 monitors the voltage signal of battery 11 and / or the charging voltage, and provides a control signal for overvoltage protection.

[0076] In one alternative implementation, the control chip 102 confirms that the battery voltage 11 is greater than the rated battery voltage 11, and / or confirms that the battery voltage 11 is greater than the rated charging voltage, and outputs a low-level first control signal; the protection chip 103 outputs a low-level voltage according to the low-level first control signal to turn off the control switch 101.

[0077] The rated charging voltage can be set according to the capacity of battery 11 and the charging protocol. The control chip 102 ensures that the control switch 101 can be enabled to open when battery 11 is charging normally, and enabled to close in case of over-discharge of battery 11.

[0078] In other embodiments, the control chip 102 can also ensure, through control signals, that the overvoltage protection circuit 10 and the battery 11 are enabled and disabled when the battery 11 is not charging or in a power-off state, thereby ensuring the normal operation of the overvoltage protection circuit 10 and the battery 11.

[0079] In other embodiments, the first end of the control switch 101 is connected to the external device 13; the control chip 102 transmits the voltage of the battery 11 to the control switch 101, and the control switch 101 supplies power to the external device 13.

[0080] When the smart device 14 uses the OTG (USB On-The-Go) function, the control switch 101 needs to be turned on. The battery 11 will supply power to support the normal operation of the connected external device 13, such as a mobile storage disk, mouse, keyboard, etc. The control chip 102 is connected to the external device 13 and generates a first control signal and a second control signal based on the device signal of the external device 13. The protection chip 103 outputs a high-level voltage according to the first and second control signals, which are both high-level voltages, thus turning on the control switch 101.

[0081] The smart device provided in the above embodiments, through the overvoltage protection circuit set in the smart device, can detect the charging voltage and battery voltage, and control the conduction state of its control switch to perform overvoltage protection in a timely manner, effectively preventing the battery from being damaged due to overvoltage, ensuring battery safety, avoiding problems such as battery bulging, overcharging or depletion, protecting battery performance, improving battery range and lifespan, and improving circuit stability and safety.

[0082] In the several embodiments provided in this application, it should be understood that the disclosed systems and devices can be implemented in other ways. Regarding the technical solutions in the embodiments of this application, it is obvious that the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. For example, the device implementation methods described above are merely illustrative. For example, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be electrical, mechanical, or other forms.

[0083] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0084] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "coupled," "connected," "linked," "set up," and "installed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0085] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0086] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0087] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. An overvoltage protection circuit, characterized in that, The overvoltage protection circuit includes: A control switch, the first end of which is connected to a battery for transmitting voltage; A control chip is disposed between the control switch and the battery. The control chip acquires the battery voltage signal and generates a control signal based on the battery voltage. A protection chip is provided, with its output terminal connected to the control switch and its input terminal connected to the control chip to receive the control signal. The protection chip outputs a voltage according to the control signal to control the conduction state of the control switch.

2. The overvoltage protection circuit according to claim 1, characterized in that, The second terminal of the control switch is connected to a voltage source, transmitting the voltage from the voltage source to the control chip; the control chip transmits the voltage from the voltage source to the battery to charge the battery.

3. The overvoltage protection circuit according to claim 2, characterized in that, The control chip converts the voltage source voltage into a charging voltage, transmits the charging voltage to charge the battery, and generates a first control signal based on the battery voltage and / or the charging voltage. The protection chip receives a first control signal from the control chip and outputs a voltage according to the first control signal to control the conduction state of the control switch.

4. The overvoltage protection circuit according to claim 3, characterized in that, The control chip confirms that the battery voltage is greater than the rated battery voltage, and / or confirms that the battery voltage is greater than the rated charging voltage, and outputs a low-level first control signal. The protection chip outputs a low-level voltage based on the low-level first control signal, so as to turn off the control switch.

5. The overvoltage protection circuit according to claim 3, characterized in that, The control chip converts the voltage from the voltage source into a charging voltage with a constant magnitude.

6. The overvoltage protection circuit according to claim 3 or 5, characterized in that, The control chip confirms that the charging voltage is greater than the rated charging voltage and outputs a low-level first control signal. The protection chip outputs a low-level voltage based on the low-level first control signal to turn off the control switch.

7. The overvoltage protection circuit according to claim 2 or 3, characterized in that, The control chip is connected to the voltage source, and the control chip generates a first control signal and a second control signal according to the voltage of the voltage source; The protection chip outputs a high-level voltage based on the first control signal and the second control signal, which are both high-level voltages, thereby turning on the control switch.

8. The overvoltage protection circuit according to claim 2, characterized in that, The control chip includes a charging chip and a processing chip that are interconnected. The charging chip is connected to the control switch, and the processing chip is connected to the protection chip. The charging chip converts the voltage source voltage into a charging voltage, transmits the charging voltage to charge the battery, and generates a first control signal based on the battery voltage and / or the charging voltage. The processing chip receives the first control signal from the charging chip and generates a third control signal based on the first control signal. The protection chip receives the third control signal from the processing chip and outputs a voltage based on the third control signal to control the conduction state of the control switch.

9. The overvoltage protection circuit according to claim 1, characterized in that, The first end of the control switch is connected to an external device; the control chip transmits the battery voltage to the control switch, and supplies power to the external device through the control switch; The control chip is connected to the external device, and the control chip receives and generates a first control signal and a second control signal based on the device signal of the external device. The protection chip outputs a high-level voltage based on the first control signal and the second control signal, which are both high-level voltages, thereby turning on the control switch.

10. A smart device, characterized in that, The intelligent device includes: Battery; An overvoltage protection circuit includes a control switch, a control chip, and a protection chip. The first terminal of the control switch is connected to the battery for voltage transmission. The control chip is positioned between the control switch and the battery, acquires the battery voltage signal, and generates a control signal based on the battery voltage. The output terminal of the protection chip is connected to the control switch, and its input terminal is connected to the control chip and receives the control signal. The protection chip outputs a voltage based on the control signal to control the conduction state of the control switch.

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