Super-capacitor dual overvoltage protection circuit and electronic equipment

Abstract

The utility model relates to a super capacitor dual overvoltage protection circuit and an electronic device, the circuit comprises a DC-DC charging circuit, the DC-DC charging circuit is used for converting a power supply, generating a voltage required by a super capacitor, detecting whether the output voltage exceeds a first preset value, if yes, stopping outputting the voltage; the comparison switch circuit comprises a voltage comparator and a switch element, the voltage comparator is connected to the output end of the DC-DC charging circuit and the enabling end of the switch element, and the voltage comparator is used for disconnecting the switch element when the value of the DC-DC charging circuit exceeds a second preset value; the switch element is connected to the output end of the DC-DC charging circuit and the super capacitor. The switch element is used for controlling the output end of the DC-DC charging circuit and the super capacitor to be switched on and off. By setting dual overvoltage protection, the safety of the super capacitor in the charging process is improved, and the reliability and safety of the electronic equipment are improved.

Description

Technical Field

[0001] This application relates to the field of supercapacitor technology, specifically to a supercapacitor dual overvoltage protection circuit and electronic device. Background Technology

[0002] Supercapacitors are a new type of energy storage device that falls between traditional capacitors and rechargeable batteries. They possess both the rapid charging and discharging characteristics of capacitors and the energy storage characteristics of batteries.

[0003] Because of their high energy density, supercapacitors are extremely vulnerable to overvoltage, which can lead to leakage, damage, or even explosion. Current overvoltage protection for supercapacitors typically involves only one layer of protection, usually found in the charging circuit; or it may involve directly detecting the voltage across the supercapacitor and cutting off the input voltage before it exceeds the maximum allowable voltage. This single-layer overvoltage protection means that if the overvoltage protection circuit itself malfunctions, the supercapacitor is left unprotected, potentially leading to the voltage exceeding the allowable value and causing an explosion. Utility Model Content

[0004] In view of the above problems, this application provides a dual overvoltage protection circuit and electronic device for supercapacitors, which solves the problem that existing supercapacitors only use a single overvoltage protection circuit for overvoltage protection. When this overvoltage protection circuit malfunctions, the voltage across the supercapacitor may exceed the allowable value, thereby causing the supercapacitor to explode or other risks.

[0005] To achieve the above objectives, the inventors provide a supercapacitor dual overvoltage protection circuit, comprising:

[0006] The DC-DC charging circuit has its input terminal connected to the power supply. The DC-DC charging circuit is used to convert the power supply to generate the voltage required by the supercapacitor and detect whether the output voltage exceeds a first preset value. If it does, the output voltage is stopped.

[0007] A comparison switch circuit includes a voltage comparator and a switching element. The voltage comparator is connected to the output terminal of the DC-DC charging circuit and the enable terminal of the switching element. The voltage comparator is used to disconnect the switching element when the output voltage of the DC-DC charging circuit exceeds a second preset value. The switching element is connected to the output terminal of the DC-DC charging circuit and a supercapacitor. The switching element is used to control the connection and disconnection between the output terminal of the DC-DC charging circuit and the supercapacitor.

[0008] In some embodiments, the DC-DC charging circuit includes:

[0009] The DC-DC power chip has its input pin connected to the power supply, its output pin connected to the input of a comparator switch circuit, and its detection pin connected to the output pin of the DC-DC power chip via a voltage divider circuit.

[0010] In some embodiments, the voltage comparator is a three-terminal adjustable reference voltage chip;

[0011] The reference terminal of the voltage comparator is connected to the output terminal of the DC-DC charging circuit, the anode of the voltage comparator is grounded, and the cathode of the voltage comparator is connected to the enable terminal of the switching element.

[0012] In some embodiments, the switching element includes:

[0013] The transistor has its emitter connected to the output of the DC-DC charging circuit, its base connected to the cathode of the voltage comparator and the output of the DC-DC charging circuit, and its collector grounded.

[0014] The MOS transistor has its gate grounded, its source connected to the output of the DC-DC charging circuit, and its drain connected to the supercapacitor.

[0015] In some embodiments, the reference terminal of the voltage comparator is connected to the output terminal of the DC-DC charging circuit via a voltage divider circuit.

[0016] In some embodiments, the first preset value is the rated voltage for supercapacitor charging.

[0017] Another technical solution is also provided: an electronic device, including a power supply, a supercapacitor, and a dual overvoltage protection circuit for the supercapacitor;

[0018] The supercapacitor dual overvoltage protection circuit is the supercapacitor dual overvoltage protection circuit described above.

[0019] The input terminal of the supercapacitor dual overvoltage protection circuit is connected to the power supply, and the output terminal of the supercapacitor dual overvoltage protection circuit is connected to the supercapacitor.

[0020] In some embodiments, it also includes:

[0021] An abnormal power failure detection circuit is connected to the output terminal of the power supply and is used to detect whether the power supply has experienced an abnormal power failure.

[0022] A power management circuit, wherein the input terminal of the power management circuit is connected to the power supply and the supercapacitor;

[0023] The SOC system has its power supply terminal connected to the output terminal of the power management circuit, and its detection terminal connected to the abnormal power failure detection circuit. The SOC system is used to store data when it receives an abnormal power failure signal sent by the abnormal power failure detection circuit.

[0024] The supercapacitor is connected to the input terminal of the power management circuit. The supercapacitor is used to supply power to the SOC system through the power management circuit when the power supply fails abnormally.

[0025] In some embodiments, it also includes:

[0026] A communication module, which is connected to the SOC system;

[0027] The SOC system is also used to send the stored data to the server via the communication module when it receives an abnormal power failure signal from the abnormal power failure detection circuit.

[0028] Unlike existing technologies, the above technical solution, when charging the supercapacitor, firstly converts the voltage output by the power supply to generate the voltage required by the supercapacitor. Simultaneously, the DC-DC charging circuit detects whether its own output voltage exceeds a first preset value. If it does, it stops outputting voltage until the output voltage drops to the first preset value; this is the first layer of supercapacitor overvoltage protection. While the DC-DC charging circuit outputs voltage to charge the supercapacitor, a voltage comparator in the comparison switching circuit compares the DC-DC charging circuit output voltage with a second preset value. When the DC-DC charging circuit output voltage exceeds the second preset value, the switching element is disconnected; when the DC-DC charging circuit output voltage does not exceed the second preset value, the switching element is turned on, allowing the DC-DC charging circuit output voltage to charge the supercapacitor; this is the second layer of supercapacitor overvoltage protection. By setting up dual overvoltage protection, the safety during the supercapacitor charging process is improved, enhancing the reliability and safety of the electronic equipment.

[0029] The above description of the invention is merely an overview of the technical solution of this application. In order to enable those skilled in the art to better understand the technical solution of this application and to implement it based on the description and drawings, and to make the above-mentioned objectives and other objectives, features and advantages of this application easier to understand, the following description is provided in conjunction with the specific embodiments and drawings of this application. Attached Figure Description

[0030] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of specific embodiments of this application and other related content, and should not be considered as limitations on this application.

[0031] In the accompanying drawings of the instruction manual:

[0032] Figure 1 This is a schematic diagram of a structure of the supercapacitor dual overvoltage protection circuit described in a specific embodiment;

[0033] Figure 2 This is a schematic diagram of the DC-DC charging circuit described in a specific embodiment;

[0034] Figure 3 A schematic diagram of the comparison switch circuit described in a specific embodiment;

[0035] Figure 4 A schematic diagram of the structure of the electronic device described in a specific embodiment;

[0036] Figure 5 This is another structural schematic diagram of the electronic device described in a specific embodiment.

[0037] The reference numerals used in the above figures are explained as follows:

[0038] 110. DC-DC charging circuit

[0039] 120. Comparison switch circuit,

[0040] 210. Power supply

[0041] 220. Supercapacitor

[0042] 230. Abnormal power failure detection circuit.

[0043] 240. Power management circuit.

[0044] 250. SOC system. Detailed Implementation

[0045] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.

[0046] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0047] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.

[0048] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.

[0049] In this application, terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy or order relationship between these entities or operations.

[0050] Unless otherwise specified, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0051] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0052] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the purpose of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0053] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0054] Please see Figure 1 This embodiment provides a supercapacitor dual overvoltage protection circuit, including:

[0055] DC-DC charging circuit 110, the input terminal of which is connected to power supply 210, is used to convert power supply 210 to generate the voltage required by supercapacitor 220, and detect whether the output voltage exceeds a first preset value. If it does, the output voltage is stopped.

[0056] The comparison switch circuit 120 includes a voltage comparator U2 and a switching element. The voltage comparator U2 is connected to the output terminal of the DC-DC charging circuit 110 and the enable terminal of the switching element. The voltage comparator U2 is used to disconnect the switching element when the output voltage of the DC-DC charging circuit 110 exceeds a second preset value. The switching element is connected to the output terminal of the DC-DC charging circuit 110 and the supercapacitor 220. The switching element is used to control the connection and disconnection between the output terminal of the DC-DC charging circuit 110 and the supercapacitor 220.

[0057] When charging the supercapacitor 220, the DC-DC charging circuit 110 first converts the voltage output from the power supply 210 to generate the voltage required by the supercapacitor 220. Simultaneously, the DC-DC charging circuit 110 detects whether its own output voltage exceeds a first preset value. If it does, it stops outputting voltage until the output voltage drops to the first preset value; this is the first level of overvoltage protection for the supercapacitor 220. While the DC-DC charging circuit 110 outputs voltage to charge the supercapacitor 220, the voltage comparator U in the comparison switching circuit 120... 2. The output voltage of the DC-DC charging circuit 110 is compared with a second preset value. When the output voltage of the DC-DC charging circuit 110 exceeds the second preset value, the switching element is turned off. Conversely, when the output voltage of the DC-DC charging circuit 110 does not exceed the second preset value, the switching element is turned on, allowing the output voltage of the DC-DC charging circuit 110 to charge the supercapacitor 220. This constitutes the second layer of overvoltage protection for the supercapacitor 220. By setting up dual overvoltage protection, the safety of the supercapacitor 220 during charging is improved, thereby enhancing the reliability and safety of the electronic equipment. ， Moreover, the increase in cost is limited, making it worthy of widespread application.

[0058] The first preset value is the rated voltage for charging the supercapacitor 220, which can output a suitable charging piezoelectric voltage to the supercapacitor 220 and avoid overvoltage. In other embodiments, the first preset value can also be the maximum voltage that the supercapacitor 220 can withstand during charging, or the voltage value between the maximum voltage and the rated voltage.

[0059] like Figure 2 As shown, in some embodiments, the DC-DC charging circuit 110 includes:

[0060] The DC-DC power chip U1 has its input pin connected to the power supply 210, its output pin connected to the input of the comparator switch circuit 120, and its detection pin connected to the output pin of the DC-DC power supply via a voltage divider circuit.

[0061] The DC-DC power chip U1 converts the voltage of the power supply 210 to generate a voltage suitable for the supercapacitor 220. The DC-DC power chip U1 also has overvoltage protection and a voltage detection pin, such as... Figure 2The DC-DC power chip U1 shown has a voltage comparison function at pin 4, VFB. Pin 4, VFB is connected to the output pin VBST of the DC-DC power chip U1 through a voltage divider circuit composed of resistors R2 and R3. When the output voltage of the DC-DC power chip U1 exceeds the set value, the output circuit inside the DC-DC power chip U1 will be shut down until its output voltage drops to the set value, thus completing the first overvoltage protection for the supercapacitor 220.

[0062] In other embodiments, a controller can be used in conjunction with a voltage divider circuit to detect the voltage output of the DC-DC power chip. The voltage divider circuit is connected to the output voltage of the DC-DC charging circuit 110, and the detected voltage is fed back to the controller. The controller is connected to the enable terminal of the DC-DC charging circuit 110. The controller determines whether the output voltage of the DC-DC charging circuit 110 exceeds a preset value. If it exceeds the preset value, the DC-DC charging circuit 110 is disconnected from operation.

[0063] like Figure 3 As shown, in some embodiments, the voltage comparator U2 is a three-terminal adjustable reference voltage chip;

[0064] The reference terminal of the voltage comparator U2 is connected to the output terminal of the DC-DC charging circuit 110, the anode of the voltage comparator U2 is grounded, and the cathode of the voltage comparator U2 is connected to the enable terminal of the switching element.

[0065] By configuring voltage comparator U2 as a three-terminal adjustable reference voltage chip, which internally contains a fixed 2.5V reference voltage source connected to the inverting input of its internal operational amplifier (op-amp), the op-amp is used as a voltage comparator to amplify the voltage difference between its non-inverting and inverting inputs. The reference terminal (R) of the three-terminal adjustable reference voltage chip is connected to the non-inverting input of this op-amp. Under normal operating conditions, the voltage at the reference terminal (R) is maintained at approximately 2.5V. When external conditions change and cause the voltage at the reference terminal (R) to rise, the op-amp further amplifies this increased voltage difference, and its output voltage rises accordingly. This increased output voltage causes an increase in the current flowing through the internal transistor, which in turn conducts between the anode and cathode of the three-terminal adjustable reference voltage chip. The voltage at the enable terminal of the switching element then decreases, controlling the switching element to open, thus disconnecting the supercapacitor 220 from the output of the DC-DC charging circuit 110.

[0066] like Figure 3 As shown, in some embodiments, the switching element includes:

[0067] Transistor Q1, the emitter of transistor Q1 is connected to the output terminal of DC-DC charging circuit 110, the base of transistor Q1 is connected to the cathode of voltage comparator U2 and the output terminal of DC-DC charging circuit 110, and the collector of transistor Q1 is grounded.

[0068] The gate of the MOSFET Q2 is grounded, the source of the MOSFET Q2 is connected to the output terminal of the DC-DC charging circuit 110, and the drain of the MOSFET Q2 is connected to the supercapacitor 220.

[0069] The base of transistor Q1 is connected to the cathode of voltage comparator U2 and the output of DC-DC charging circuit 110. When the voltage at the reference terminal of voltage comparator U2 does not exceed 2.5V, the anode and cathode of voltage comparator U2 will not conduct. When the voltage at the reference terminal of voltage comparator U2 exceeds 2.5V, the anode and cathode of voltage comparator U2 conduct, which turns on transistor Q1, and then grounds the gate of MOSFET Q2. MOSFET Q2 is then turned off, thereby disconnecting supercapacitor 220 from DC-DC charging circuit 110, thus achieving overvoltage protection.

[0070] in, Figure 3 SC1 is a 220 supercapacitor.

[0071] In some embodiments, the reference terminal of the voltage comparator U2 is connected to the output terminal of the DC-DC charging circuit 110 via a voltage divider circuit.

[0072] The voltage at the output of the DC-DC charging circuit 110 is divided by resistors R5 and R6 and then input to the reference terminal of voltage comparator U2. When the voltage divided by resistors R5 and R6 exceeds 2.5V, the anode and cathode of voltage comparator U2 are turned on, the base of transistor Q1 is grounded, thereby turning on transistor Q1 and turning off MOSFET Q2.

[0073] In other embodiments, the switching element may also be a relay, etc. The control terminal of the relay is connected to the voltage comparator U2. When the voltage output by the DC-DC charging circuit 110 exceeds the preset voltage, the output terminal of the DC-DC charging circuit 110 is disconnected from the supercapacitor 220 through the relay to achieve overvoltage protection.

[0074] Please see Figure 4-5 In another embodiment, an electronic device includes a power supply 210, a supercapacitor 220, and a supercapacitor dual overvoltage protection circuit.

[0075] The input terminal of the supercapacitor dual overvoltage protection circuit is connected to the power supply 210, and the output terminal of the supercapacitor dual overvoltage protection circuit is connected to the supercapacitor 220.

[0076] The supercapacitor dual overvoltage protection circuit includes:

[0077] DC-DC charging circuit 110, the input terminal of which is connected to power supply 210, is used to convert power supply 210 to generate the voltage required by supercapacitor 220, and detect whether the output voltage exceeds a first preset value. If it does, the output voltage is stopped.

[0078] The comparison switch circuit 120 includes a voltage comparator U2 and a switching element. The voltage comparator U2 is connected to the output terminal of the DC-DC charging circuit 110 and the enable terminal of the switching element. The voltage comparator U2 is used to disconnect the switching element when the DC-DC charging circuit 110 exceeds a second preset value. The switching element is connected to the output terminal of the DC-DC charging circuit 110 and the supercapacitor 220. The switching element is used to control the connection between the output terminal of the DC-DC charging circuit 110 and the supercapacitor 220.

[0079] When charging the supercapacitor 220, the DC-DC charging circuit 110 first converts the voltage output from the power supply 210 to generate the voltage required by the supercapacitor 220. Simultaneously, the DC-DC charging circuit 110 detects whether its own output voltage exceeds a first preset value. If it does, it stops outputting voltage until the output voltage drops to the first preset value; this is the first level of overvoltage protection for the supercapacitor 220. While the DC-DC charging circuit 110 outputs voltage to charge the supercapacitor 220, the voltage comparator U2 in the comparison switch circuit 120 converts the DC-DC charging voltage to the required voltage. The output voltage of the DC-DC charging circuit 110 is compared with a second preset value. When the output voltage of the DC-DC charging circuit 110 exceeds the second preset value, the switching element is turned off. When the output voltage of the DC-DC charging circuit 110 does not exceed the second preset value, the switching element is turned on, so that the output voltage of the DC-DC charging circuit 110 charges the supercapacitor 220. This is the second overvoltage protection for the supercapacitor 220. By setting up dual overvoltage protection, the safety of the supercapacitor 220 during charging is improved, thereby enhancing the reliability and safety of the electronic equipment. The cost increase is limited, making it worthy of widespread application.

[0080] like Figure 2 As shown, in some embodiments, the DC-DC charging circuit 110 includes:

[0081] The DC-DC power chip U1 has its input pin connected to the power supply 210, its output pin connected to the input of the comparator switch circuit 120, and its detection pin connected to the output pin of the DC-DC power supply via a voltage divider circuit.

[0082] The DC-DC power chip U1 converts the voltage of the power supply 210 to generate a voltage suitable for the supercapacitor 220. The DC-DC power chip U1 also has overvoltage protection and a voltage detection pin, such as... Figure 2 The DC-DC power chip U1 shown has a voltage comparison function at pin 4, VFB. Pin 4, VFB is connected to the output pin VBST of the DC-DC power chip U1 through a voltage divider circuit composed of resistors R2 and R3. When the output voltage of the DC-DC power chip U1 exceeds the set value, the output circuit inside the DC-DC power chip U1 will be shut down until its output voltage drops to the set value, thus completing the first overvoltage protection for the supercapacitor 220.

[0083] In other embodiments, a controller can be used in conjunction with a voltage divider circuit to detect the voltage output of the DC-DC power chip. The voltage divider circuit is connected to the output voltage of the DC-DC charging circuit 110, and the detected voltage is fed back to the controller. The controller is connected to the enable terminal of the DC-DC charging circuit 110. The controller determines whether the output voltage of the DC-DC charging circuit 110 exceeds a preset value. If it exceeds the preset value, the DC-DC charging circuit 110 is disconnected from operation.

[0084] Please see Figure 3 In some embodiments, the voltage comparator U2 is a three-terminal adjustable reference voltage chip;

[0085] The reference terminal of the voltage comparator U2 is connected to the output terminal of the DC-DC charging circuit 110, the anode of the voltage comparator U2 is grounded, and the cathode of the voltage comparator U2 is connected to the enable terminal of the switching element.

[0086] By configuring voltage comparator U2 as a three-terminal adjustable reference voltage chip, which internally contains a fixed 2.5V reference voltage source connected to the inverting input of its internal operational amplifier (op-amp), the op-amp is used as a voltage comparator to amplify the voltage difference between its non-inverting and inverting inputs. The reference terminal (R) of the three-terminal adjustable reference voltage chip is connected to the non-inverting input of this op-amp. Under normal operating conditions, the voltage at the reference terminal (R) is maintained at approximately 2.5V. When external conditions change and cause the voltage at the reference terminal (R) to rise, the op-amp further amplifies this increased voltage difference, and its output voltage rises accordingly. This increased output voltage causes an increase in the current flowing through the internal transistor, which in turn conducts between the anode and cathode of the three-terminal adjustable reference voltage chip. The voltage at the enable terminal of the switching element then decreases, controlling the switching element to open, thus disconnecting the supercapacitor 220 from the output of the DC-DC charging circuit 110.

[0087] Please see Figure 3 In some embodiments, the switching element includes:

[0088] Transistor Q1, the emitter of transistor Q1 is connected to the output terminal of DC-DC charging circuit 110, the base of transistor Q1 is connected to the cathode of voltage comparator U2 and the output terminal of DC-DC charging circuit 110, and the collector of transistor Q1 is grounded.

[0089] The gate of the MOSFET Q2 is grounded, the source of the MOSFET Q2 is connected to the output terminal of the DC-DC charging circuit 110, and the drain of the MOSFET Q2 is connected to the supercapacitor 220.

[0090] The base of transistor Q1 is connected to the cathode of voltage comparator U2 and the output of DC-DC charging circuit 110. When the voltage at the reference terminal of voltage comparator U2 does not exceed 2.5V, the anode and cathode of voltage comparator U2 will not conduct. When the voltage at the reference terminal of voltage comparator U2 exceeds 2.5V, the anode and cathode of voltage comparator U2 conduct, which turns on transistor Q1, and then grounds the gate of MOSFET Q2. MOSFET Q2 is then turned off, thereby disconnecting supercapacitor 220 from DC-DC charging circuit 110, thus achieving overvoltage protection.

[0091] In some embodiments, the reference terminal of the voltage comparator U2 is connected to the output terminal of the DC-DC charging circuit 110 via a voltage divider circuit.

[0092] The voltage at the output of the DC-DC charging circuit 110 is divided by resistors R5 and R6 and then input to the reference terminal of voltage comparator U2. When the voltage divided by resistors R5 and R6 exceeds 2.5V, the anode and cathode of voltage comparator U2 are turned on, the base of transistor Q1 is grounded, thereby turning on transistor Q1 and turning off MOSFET Q2.

[0093] In other embodiments, the switching element may also be a relay, etc. The control terminal of the relay is connected to the voltage comparator U2. When the voltage output by the DC-DC charging circuit 110 exceeds the preset voltage, the output terminal of the DC-DC charging circuit 110 is disconnected from the supercapacitor 220 through the relay to achieve overvoltage protection.

[0094] Please see Figure 5 In some embodiments, the electronic device further includes:

[0095] Abnormal power failure detection circuit 230, the abnormal power failure detection circuit 230 is connected to the output terminal of the power supply 210, the abnormal power failure detection circuit 230 is used to detect whether the power supply 210 has an abnormal power failure;

[0096] A power management circuit 240, the input terminal of which is connected to a power supply 210 and a supercapacitor 220;

[0097] The SOC system 250 has its power supply terminal connected to the output terminal of the power management circuit 240, and its detection terminal connected to the abnormal power failure detection circuit 230. The SOC system 250 is used to store data when it receives an abnormal power failure signal sent by the abnormal power failure detection circuit 230.

[0098] The supercapacitor 220 is connected to the input terminal of the power management circuit 240. The supercapacitor 220 is used to supply power to the SOC system 250 through the power management circuit 240 when the power supply 210 fails to power normally.

[0099] When there is no overvoltage in the DC-DC charging circuit 110 and the comparator switch circuit 120 of the supercapacitor 220 and the power supply 210 fails to power, the abnormal power failure detection circuit 230 sends an abnormal power failure signal to the SOC system 250. At the same time, the power stored in the supercapacitor 220 will automatically supply power to the power management circuit 240, so that the SOC system 250 has enough time to save important data.

[0100] In some embodiments, it also includes:

[0101] A communication module is connected to the SOC system 250;

[0102] The SOC system 250 is also used to send the stored data to the server through the communication module when it receives an abnormal power failure signal sent by the abnormal power failure detection circuit 230.

[0103] By setting up a communication module, when the power supply 210 fails to power normally, the SOC system 250 will send the stored data to the server through the communication module, ensuring that the data in the electronic device can be obtained even when the electronic device has not been restored to normal power supply.

[0104] In some embodiments, the entire hardware device of the electronic device mainly comprises four parts: an external power supply, a DC-DC charging circuit with overvoltage protection (first overvoltage protection), a comparison switching circuit with a voltage comparator, and a supercapacitor.

[0105] The power supply simultaneously powers both the power management circuit and the DC-DC charging circuit.

[0106] The power management circuit supplies power to the SOC system.

[0107] A DC-DC charging circuit with overvoltage protection. Figure 2 As shown; its function is to convert the voltage of the external power supply to generate a voltage suitable for the supercapacitor. Simultaneously, this circuit has overvoltage protection functionality, i.e. Figure 2 The fourth pin of U1 contains a voltage comparator. When the output voltage exceeds the set value, it will automatically shut down the output circuit until the output voltage drops to the set value. This is the first layer of supercapacitor overvoltage protection.

[0108] The voltage output from the supercapacitor charging circuit serves as the power input to a switching circuit with a voltage comparator. This voltage comparator monitors the input voltage, and when the input voltage exceeds a set value, the switching circuit shuts off to prevent the supercapacitor voltage from exceeding the maximum allowable value. This is the second layer of supercapacitor overvoltage protection. Figure 3 The circuit shown is a comparator switch circuit with a voltage comparator. U2 has an internal reference voltage of 2.5V. When the voltage drop across resistors R5 and R6 exceeds 2.5V, terminal 2 of U2 will be grounded to GND, which turns on transistor Q1. This causes the gate voltage of MOSFET (or relay) Q2 to increase, thus turning off Q2. This, in turn, disconnects the supercapacitor from the VCC_SC_IN power supply, achieving overvoltage protection.

[0109] When neither the DC-DC charging circuit nor the comparator switch circuit experiences overvoltage, or when the power supply fails abnormally, the abnormal power failure detection circuit 230 sends an abnormal power failure signal to the SOC system. Simultaneously, the power stored in the supercapacitor automatically supplies power to the power management circuit, giving the SOC sufficient time to save important data.

[0110] The advantages of the supercapacitor dual overvoltage protection circuit are: the circuit is simple and does not require dedicated charging and protection chips to achieve the dual overvoltage protection function of the supercapacitor.

[0111] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of patent protection of this application. Any technical solutions that are based on the essential concept of this application and utilize the content described in the text and drawings of this application, resulting in equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this application.

Claims

1. A supercapacitor dual overvoltage protection circuit, characterized in that, include: The DC-DC charging circuit has its input terminal connected to the power supply. The DC-DC charging circuit is used to convert the power supply to generate the voltage required by the supercapacitor and detect whether the output voltage exceeds a first preset value. If it does, the output voltage is stopped. A comparison switch circuit includes a voltage comparator and a switching element. The voltage comparator is connected to the output terminal of the DC-DC charging circuit and the enable terminal of the switching element. The voltage comparator is used to disconnect the switching element when the output voltage of the DC-DC charging circuit exceeds a second preset value. The switching element is connected to the output terminal of the DC-DC charging circuit and a supercapacitor. The switching element is used to control the connection and disconnection between the output terminal of the DC-DC charging circuit and the supercapacitor.

2. The supercapacitor dual overvoltage protection circuit according to claim 1, characterized in that, The DC-DC charging circuit includes: The DC-DC power chip has its input pin connected to the power supply, its output pin connected to the input of a comparator switch circuit, and its detection pin connected to the output pin of the DC-DC power chip via a voltage divider circuit.

3. The supercapacitor dual overvoltage protection circuit according to claim 1, characterized in that, The voltage comparator is a three-terminal adjustable reference voltage chip; The reference terminal of the voltage comparator is connected to the output terminal of the DC-DC charging circuit, the anode of the voltage comparator is grounded, and the cathode of the voltage comparator is connected to the enable terminal of the switching element.

4. The supercapacitor dual overvoltage protection circuit according to claim 3, characterized in that, The switching element includes: The transistor has its emitter connected to the output of the DC-DC charging circuit, its base connected to the cathode of the voltage comparator and the output of the DC-DC charging circuit, and its collector connected to ground. The MOS transistor has its gate grounded, its source connected to the output of the DC-DC charging circuit, and its drain connected to the supercapacitor.

5. The supercapacitor dual overvoltage protection circuit according to claim 3, characterized in that, The reference terminal of the voltage comparator is connected to the output terminal of the DC-DC charging circuit via a voltage divider circuit.

6. The supercapacitor dual overvoltage protection circuit according to claim 1, characterized in that, The first preset value is the rated voltage for charging the supercapacitor.

7. An electronic device, characterized in that, Includes power supply, supercapacitor, and supercapacitor dual overvoltage protection circuit; The supercapacitor dual overvoltage protection circuit is the supercapacitor dual overvoltage protection circuit according to any one of claims 1-6; The input terminal of the supercapacitor dual overvoltage protection circuit is connected to the power supply, and the output terminal of the supercapacitor dual overvoltage protection circuit is connected to the supercapacitor.

8. The electronic device according to claim 7, characterized in that, Also includes: An abnormal power failure detection circuit is connected to the output terminal of the power supply and is used to detect whether the power supply has experienced an abnormal power failure. A power management circuit, wherein the input terminal of the power management circuit is connected to the power supply and the supercapacitor; The SOC system has its power supply terminal connected to the output terminal of the power management circuit, and its detection terminal connected to the abnormal power failure detection circuit. The SOC system is used to store data when it receives an abnormal power failure signal sent by the abnormal power failure detection circuit. The supercapacitor is connected to the input terminal of the power management circuit. The supercapacitor is used to supply power to the SOC system through the power management circuit when the power supply fails abnormally.

9. The electronic device according to claim 8, characterized in that, Also includes: A communication module, which is connected to the SOC system; The SOC system is also used to send the stored data to the server via the communication module when it receives an abnormal power failure signal from the abnormal power failure detection circuit.

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