Battery charging circuit and electronic device

Abstract

A battery charging circuit and an electronic device belong to the technical field of power supply. The temperature of a battery assembly is detected by a temperature detection circuit to output a first detection voltage. A comparison circuit outputs a high-level first signal and a high-level second signal in response to the first detection voltage being in a first preset interval, and outputs a low-level first signal or a low-level second signal in response to the first detection voltage being outside the first preset interval. An output circuit outputs a second detection voltage in a second preset interval when the first signal and the second signal are both high. A power supply circuit converts a supply direct current into an output direct current to charge the battery assembly in response to the second detection voltage being in the second preset interval. The power supply circuit associates the first preset interval with a second charging protocol based on a first charging protocol, and associates the second preset interval with the first charging protocol. Therefore, the safe charging temperature is flexibly adjusted.

Description

Technical Field

[0001] This application belongs to the field of power supply circuit technology, and in particular relates to a battery charging circuit and electronic device. Background Technology

[0002] In rechargeable lithium battery products, charging safety is a crucial design consideration. In small electronic products, the safe charging temperature for lithium batteries is generally between 0°C and 45°C. However, the charging chips used with lithium batteries vary widely in specifications. Typically, these chips adhere to the JEITA standard, which allows for normal charging within the 45°C to 60°C range (0°C to 60°C). Therefore, when used with the desired lithium battery in a product, this does not meet the safety requirements for charging temperature.

[0003] Therefore, the related battery charging circuit cannot adjust the safe charging temperature and has poor flexibility. Utility Model Content

[0004] The purpose of this application is to provide a battery charging circuit and electronic device, which aims to solve the problems of related battery charging circuits being unable to adjust the safe charging temperature and having poor flexibility.

[0005] This application provides a battery charging circuit, including:

[0006] A temperature detection circuit is used to detect the temperature of the battery assembly and output a first detection voltage; the first detection voltage conforms to a first charging protocol.

[0007] A comparison circuit, connected to the temperature detection circuit, is used to output a high-level first signal and a high-level second signal in response to the first detection voltage being within a first preset range, and to output a low-level first signal or a low-level second signal in response to the first detection voltage being outside the first preset range.

[0008] An output circuit, connected to the comparison circuit, is used to output a second detection voltage located in a second preset range when both the first signal and the second signal are at a high level, and to output a second detection voltage located outside the second preset range when either the first signal or the second signal is at a low level.

[0009] A power supply circuit, connected to the output circuit, is used to receive DC power and, in response to the second detected voltage being within a second preset range, converts the DC power supply into DC power output to charge the battery assembly.

[0010] The power supply circuit is based on a first charging protocol, the first preset interval is associated with a second charging protocol, and the second preset interval is associated with the first charging protocol.

[0011] In one embodiment, the upper limit of the first preset interval is a first voltage, and the lower limit of the first preset interval is a second voltage; the comparison circuit includes:

[0012] The first comparison module is connected to the temperature detection circuit and is used to compare the first detection voltage with the first voltage and output the first signal according to the comparison result.

[0013] The second comparison module is connected to the temperature detection circuit and is used to compare the first detection voltage with the second voltage, and output the second signal according to the comparison result.

[0014] In one embodiment, the power supply circuit is further configured to provide a reference voltage; the battery charging circuit further includes:

[0015] A voltage divider circuit, connected to the first comparison module, the second comparison module, and the power supply circuit, is used to divide the reference voltage to output the first voltage and the second voltage.

[0016] In one embodiment, the voltage divider circuit includes a first resistor, a second resistor, and a third resistor;

[0017] The first end of the first resistor forms the input terminal of the voltage divider circuit and is connected to the power supply circuit to access the reference voltage;

[0018] The second end of the first resistor and the first end of the second resistor are connected and together form the first output terminal of the voltage divider circuit, which is connected to the first comparison module to output the first voltage;

[0019] The second end of the second resistor and the first end of the third resistor are connected to form the second output terminal of the voltage divider circuit, which is connected to the second comparator module to output the second voltage; the second end of the third resistor is connected to the power supply ground.

[0020] In one embodiment, the first comparison module includes a first comparator;

[0021] The non-inverting input terminal of the first comparator forms the first input terminal of the first comparator module and is connected to the voltage divider circuit to receive the first voltage;

[0022] The inverting input terminal of the first comparator forms the second input terminal of the first comparison module, which is connected to the temperature detection circuit to receive the first detection voltage;

[0023] The output terminal of the first comparator constitutes the output terminal of the first comparison module and is connected to the output circuit to output the first signal.

[0024] In one embodiment, the second comparison module includes a second comparator;

[0025] The non-inverting input terminal of the second comparator forms the first input terminal of the second comparison module, which is connected to the temperature detection circuit to receive the first detection voltage;

[0026] The inverting input terminal of the second comparator forms the second input terminal of the second comparison module, which is connected to the voltage divider circuit to receive the second voltage;

[0027] The output terminal of the second comparator constitutes the output terminal of the second comparison module and is connected to the output circuit to output the second signal.

[0028] In one embodiment, the power supply circuit includes a charging chip, an inductor, a first capacitor, a second capacitor, a third capacitor, and a fourth capacitor;

[0029] The charging input voltage terminal of the charging chip and the first terminal of the first capacitor are connected and together form the DC power input terminal of the power supply circuit, so as to be connected to the DC power supply.

[0030] The low-side FET driver positive power output terminal of the charging chip is connected to the first terminal of the fourth capacitor to form the reference voltage output terminal of the power supply circuit, so as to output the reference voltage.

[0031] The first switching terminal of the charging chip is connected to the second switching terminal of the charging chip, the first terminal of the second capacitor and the first terminal of the inductor. The second terminal of the second capacitor is connected to the high-side FET driving power supply terminal of the charging chip. The first ground terminal of the charging chip, the second ground terminal of the charging chip, the second terminal of the first capacitor, the second terminal of the third capacitor and the second terminal of the fourth capacitor are all connected to the power supply ground.

[0032] The battery voltage detection terminal of the charging chip, the second terminal of the inductor, and the first terminal of the third capacitor are connected and together constitute the output DC power terminal of the power supply circuit, which is connected to the battery assembly to output the output DC power.

[0033] The battery temperature voltage input terminal of the charging chip constitutes the second detection voltage input terminal of the power supply circuit and is connected to the output circuit to receive the second detection voltage.

[0034] In one embodiment, the output circuit includes a first diode, a second diode, a fourth resistor, and a fifth resistor;

[0035] The cathode of the first diode forms the first input terminal of the output circuit and is connected to the comparator circuit to receive the first signal;

[0036] The cathode of the second diode forms the second input terminal of the output circuit, which is connected to the comparator circuit to receive the second signal;

[0037] The first end of the fourth resistor constitutes the power supply terminal of the output circuit and is connected to the power supply circuit to access the reference voltage.

[0038] The second end of the fourth resistor, the first end of the fifth resistor, the positive terminal of the first diode, and the positive terminal of the second diode are connected and together form the output terminal of the output circuit, which is connected to the power supply circuit to output the second detection voltage.

[0039] The second end of the fifth resistor is connected to the power supply ground.

[0040] In one embodiment, the temperature detection circuit includes a thermistor and a sixth resistor;

[0041] The first end of the sixth resistor constitutes the power supply terminal of the temperature detection circuit and is connected to the power supply circuit to access the reference voltage.

[0042] The first end of the thermistor and the second end of the sixth resistor are connected and together form the output terminal of the temperature detection circuit, which is connected to the comparison circuit to output the first detection voltage.

[0043] The second terminal of the thermistor is connected to the power supply ground.

[0044] This utility model embodiment also provides an electronic device, which includes the battery charging circuit described above.

[0045] The beneficial effects of this utility model embodiment compared with the prior art are as follows: When the first detection voltage is within the first preset range, a second detection voltage within the second preset range is output, thereby the power supply circuit converts the supplied DC power into output DC power to charge the battery assembly; similarly, when the first detection voltage is outside the first preset range, a second detection voltage outside the second preset range is output, thereby the power supply circuit stops converting the supplied DC power into output DC power to stop charging the battery assembly; that is, charging according to the second charging protocol is achieved when using a power supply circuit based on the first charging protocol; therefore, the power supply circuit based on the first charging protocol performs DC power conversion according to the safe charging temperature of the second charging protocol, flexibly adjusting the safe charging temperature and realizing the conversion between charging protection protocols. Attached Figure Description

[0046] To more clearly illustrate the technical utility model in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 A schematic diagram of a battery charging circuit provided in an embodiment of this application;

[0048] Figure 2 This is a schematic diagram of a comparison circuit in a battery charging circuit provided in an embodiment of this application.

[0049] Figure 3 This is a schematic diagram of another structure of a battery charging circuit provided in one embodiment of this application;

[0050] Figure 4 This is a partial example circuit diagram of a battery charging circuit provided in an embodiment of this application. Detailed Implementation

[0051] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0052] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0053] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0055] Figure 1 A schematic diagram of the battery charging circuit provided in a preferred embodiment of this application is shown. For ease of explanation, only the parts relevant to this embodiment are shown, and are described in detail below:

[0056] The aforementioned battery charging circuit, connected to the battery assembly 80, includes a temperature detection circuit 10, a comparison circuit 20, an output circuit 30, and a power supply circuit 40.

[0057] Temperature detection circuit 10 is used to detect the temperature of battery assembly 80 and output a first detection voltage; the first detection voltage conforms to a first charging protocol.

[0058] The comparator circuit 20 is connected to the temperature detection circuit 10 and is used to output a high-level first signal and a high-level second signal in response to the first detection voltage being within a first preset range, and to output a low-level first signal or a low-level second signal in response to the first detection voltage being outside the first preset range.

[0059] The output circuit 30, connected to the comparator circuit 20, is used to output a second detection voltage located in a second preset range when both the first signal and the second signal are at a high level, and to output a second detection voltage located outside the second preset range when either the first signal or the second signal is at a low level.

[0060] The power supply circuit 40 is connected to the output circuit 30 and is used to receive the DC power supply. In response to the second detection voltage being in the second preset range, the DC power supply is converted into the output DC power to charge the battery assembly 80.

[0061] The power supply circuit 40 is based on a first charging protocol, the first preset interval is associated with a second charging protocol, and the second preset interval is associated with the first charging protocol.

[0062] It should be noted that in the prior art, the power supply circuit 40 conforming to the first charging protocol converts the supplied DC power into output DC power in response to the detected voltage being located in the second preset range. The power supply circuit 40 conforming to the second charging protocol converts the supplied DC power into output DC power in response to the detected voltage being located in the first preset range. In this application, the first detected voltage located in the first preset range is converted into a second detected voltage located in the second preset range by a comparison circuit and an output circuit, thereby realizing the conversion of the charging protocol.

[0063] In practice, the first charging protocol can be the JEITA standard, and the second charging protocol can be the HOTCOLD standard.

[0064] like Figure 2 As shown, the upper limit of the first preset interval is the first voltage, and the lower limit of the first preset interval is the second voltage; the comparison circuit 20 includes a first comparison module 21 and a second comparison module 22.

[0065] The first comparison module 21 is connected to the temperature detection circuit 10 and is used to compare the first detection voltage with the first voltage and output the first signal according to the comparison result.

[0066] The second comparison module 22 is connected to the temperature detection circuit 10 and is used to compare the first detection voltage with the second voltage and output a second signal based on the comparison result.

[0067] Understandably, the first comparison module 21 is used to output a first high-level signal in response to a first detection voltage being less than a first voltage, and to output a first low-level signal in response to a first detection voltage being greater than or equal to a first voltage; the second comparison module 22 is used to output a second low-level signal in response to a first detection voltage being greater than or equal to a second voltage, and to output a second high-level signal in response to a first detection voltage being less than a second voltage.

[0068] Through the above technical solution, the comparator circuit 20 outputs a high-level first signal and a high-level second signal in response to the first detection voltage being within the first preset range, and outputs a low-level first signal or a low-level second signal in response to the first detection voltage being outside the first preset range.

[0069] like Figure 3 As shown, the power supply circuit 40 is also used to provide a reference voltage; the battery charging circuit also includes a voltage divider circuit 50.

[0070] The voltage divider circuit 50 is connected to the first comparison module 21, the second comparison module 22 and the power supply circuit 40, and is used to divide the reference voltage to output the first voltage and the second voltage.

[0071] The first and second voltages are provided by the voltage divider circuit 50, which is simple and reliable.

[0072] Figure 4 The illustration shows a partial example circuit structure of a battery charging circuit provided by an embodiment of the present invention. For ease of explanation, only the parts related to the embodiment of the present invention are shown, and are described in detail below:

[0073] The voltage divider circuit 50 includes a first resistor R1, a second resistor R2, and a third resistor R3.

[0074] The first end of the first resistor R1 forms the input terminal of the voltage divider circuit 50 and is connected to the power supply circuit 40 to receive a reference voltage. The second end of the first resistor R1 and the first end of the second resistor R2 are connected and together form the first output terminal of the voltage divider circuit 50, which is connected to the first comparator module 20 to output a first voltage. The second end of the second resistor R2 and the first end of the third resistor R3 are connected and together form the second output terminal of the voltage divider circuit 50, which is connected to the second comparator module 20 to output a second voltage. The second end of the third resistor R3 is connected to the power supply ground.

[0075] This voltage divider circuit 50 uses three circuits to output two voltages. The hardware design is simple and the reliability is high.

[0076] The first comparison module 20 includes a first comparator U1.

[0077] The non-inverting input terminal of the first comparator U1 forms the first input terminal of the first comparator module 20 and is connected to the voltage divider circuit 50 to receive the first voltage; the inverting input terminal of the first comparator U1 forms the second input terminal of the first comparator module 20 and is connected to the temperature detection circuit 10 to receive the first detection voltage; the output terminal of the first comparator U1 forms the output terminal of the first comparator module 20 and is connected to the output circuit 30 to output the first signal.

[0078] The first comparison module 20 has a simple hardware design and high reliability.

[0079] The second comparison module 20 includes a second comparator U2.

[0080] The non-inverting input of the second comparator U2 forms the first input of the second comparison module 20 and is connected to the temperature detection circuit 10 to receive the first detection voltage; the inverting input of the second comparator U2 forms the second input of the second comparison module 20 and is connected to the voltage divider circuit 50 to receive the second voltage; the output of the second comparator U2 forms the output of the second comparison module 20 and is connected to the output circuit 30 to output the second signal.

[0081] The second comparison module 20 has a simple hardware design and high reliability.

[0082] The power supply circuit 40 includes a charging chip U3, an inductor L1, a first capacitor C1, a second capacitor C2, a third capacitor C3, and a fourth capacitor C4.

[0083] The charging input voltage terminal VBUS of the charging chip U3 and the first terminal of the first capacitor C1 are connected and together form the DC power input terminal of the power supply circuit 40 to receive DC power; the low-side field-effect transistor of the charging chip U3... The positive power output terminal REGN of the transistor (FET) and the first terminal of the fourth capacitor C4 are connected to form the reference voltage output terminal of the power supply circuit 40 to output a reference voltage. The first switching terminal SW1 of the charging chip U3 is connected to the second switching terminal SW2 of the charging chip U3, the first terminal of the second capacitor C2 and the first terminal of the inductor L1. The second terminal of the second capacitor C2 is connected to the high-side FET driving power supply terminal of the charging chip U3. The first ground terminal GND1, the second ground terminal GND2 of the charging chip U3, the second terminal of the first capacitor C1, the second terminal of the third capacitor C3 and the second terminal of the fourth capacitor C4 are all connected to the power supply ground. The battery voltage detection terminal BAT of the charging chip U3, the second terminal of the inductor L1 and the first terminal of the third capacitor C3 are connected to form the DC output terminal of the power supply circuit 40, which is connected to the battery assembly 80 to output DC power. The battery temperature voltage input terminal TS of the charging chip U3 forms the second detection voltage input terminal of the power supply circuit 40, which is connected to the output circuit 30 to receive the second detection voltage.

[0084] It should be noted that the charging chip U3 is based on the first charging protocol.

[0085] The output circuit 30 includes a first diode D1, a second diode D2, a fourth resistor R4, and a fifth resistor R5.

[0086] The cathode of the first diode D1 forms the first input terminal of the output circuit 30 and is connected to the comparator circuit 20 to receive the first signal; the cathode of the second diode D2 forms the second input terminal of the output circuit 30 and is connected to the comparator circuit 20 to receive the second signal; the first end of the fourth resistor R4 forms the power supply terminal of the output circuit 30 and is connected to the power supply circuit 40 to receive the reference voltage; the second end of the fourth resistor R4, the first end of the fifth resistor R5, the anode of the first diode D1, and the anode of the second diode D2 are connected and together form the output terminal of the output circuit 30, which is connected to the power supply circuit 40 to output the second detection voltage; the second end of the fifth resistor R5 is connected to the power supply ground.

[0087] It is understandable that when both the first signal and the second signal are at a high level, the first diode D1 and the second diode D2 are cut off, and the voltage divider circuit 50 composed of the fourth resistor R4 and the fifth resistor R5 divides the reference voltage so that the output circuit 30 outputs the upper limit voltage of the second preset range.

[0088] When the first signal or the second signal is low, the first diode D1 or the second diode D2 is turned on, so that the output circuit 30 outputs the lower limit voltage of the second preset range, wherein the lower limit voltage of the second preset range is the turn-on voltage of the first diode D1 or the second diode D2 (0.3V).

[0089] Temperature detection circuit 10 includes a thermistor RT1 and a sixth resistor R6;

[0090] The first end of the sixth resistor R6 forms the power supply terminal of the temperature detection circuit 10 and is connected to the power supply circuit 40 to access the reference voltage; the first end of the thermistor RT1 and the second end of the sixth resistor R6 are connected and together form the output terminal of the temperature detection circuit 10, which is connected to the comparator circuit 20 to output the first detection voltage; the second end of the thermistor RT1 is connected to the power supply ground.

[0091] It is understandable that the thermistor RT1 can have a negative temperature coefficient.

[0092] The temperature detection circuit 10 is simple and reliable.

[0093] The following is based on the working principle. Figure 4 Further explanation is provided below:

[0094] The sixth resistor R6 and the thermistor RT1 divide the reference voltage and output a first detection signal, which conforms to the first charging protocol. The first resistor R1 to the third resistor R3 divide the reference voltage to output a first voltage and a second voltage, wherein the upper limit of the first preset interval is the first voltage and the lower limit of the first preset interval is the second voltage.

[0095] The first comparator U1 outputs a high-level first signal in response to a first detection voltage being less than a first voltage, and outputs a low-level first signal in response to a first detection voltage being greater than or equal to the first voltage; the second comparator U2 outputs a high-level second signal in response to a first detection voltage being greater than or equal to a second voltage, and outputs a low-level second signal in response to a first detection voltage being less than the second voltage.

[0096] When both the first and second signals are high, the first diode D1 and the second diode D2 are cut off. The voltage divider circuit 50, consisting of the fourth resistor R4 and the fifth resistor R5, divides the reference voltage so that the output circuit 30 outputs the upper limit voltage of the second preset range. When either the first or second signal is low, the first diode D1 or the second diode D2 is turned on so that the output circuit 30 outputs the lower limit voltage of the second preset range, where the lower limit voltage of the second preset range is the turn-on voltage of the first diode D1 or the second diode D2 (0.3V).

[0097] Based on the first charging protocol, the charging chip U3, in response to the second detection voltage it receives being within the second preset range, converts the supplied DC power into output DC power. Conversely, if the second detection voltage it receives is outside the second preset range, the charging chip U3 stops converting the supplied DC power into output DC power. Thus, the charging chip performs DC power conversion according to the safe charging temperature of the second charging protocol, flexibly adjusting the safe charging temperature and achieving switching between charging protection protocols.

[0098] This utility model embodiment also provides an electronic device, which includes the battery charging circuit described above.

[0099] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0100] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A battery charging circuit, characterized in that, Connected to the battery assembly, including: A temperature detection circuit is used to detect the temperature of the battery assembly and output a first detection voltage; the first detection voltage conforms to a first charging protocol. A comparison circuit, connected to the temperature detection circuit, is used to output a high-level first signal and a high-level second signal in response to the first detection voltage being within a first preset range, and to output a low-level first signal or a low-level second signal in response to the first detection voltage being outside the first preset range. An output circuit, connected to the comparison circuit, is used to output a second detection voltage located in a second preset range when both the first signal and the second signal are at a high level, and to output a second detection voltage located outside the second preset range when either the first signal or the second signal is at a low level. A power supply circuit, connected to the output circuit, is used to receive DC power and, in response to the second detected voltage being within a second preset range, converts the DC power supply into DC power output to charge the battery assembly. The power supply circuit is based on a first charging protocol, the first preset interval is associated with a second charging protocol, and the second preset interval is associated with the first charging protocol.

2. The battery charging circuit as described in claim 1, characterized in that, The upper limit of the first preset interval is a first voltage, and the lower limit of the first preset interval is a second voltage; the comparison circuit includes: The first comparison module is connected to the temperature detection circuit and is used to compare the first detection voltage with the first voltage and output the first signal according to the comparison result. The second comparison module is connected to the temperature detection circuit and is used to compare the first detection voltage with the second voltage, and output the second signal according to the comparison result.

3. The battery charging circuit as described in claim 2, characterized in that, The power supply circuit is also used to provide a reference voltage; the battery charging circuit further includes: A voltage divider circuit, connected to the first comparison module, the second comparison module, and the power supply circuit, is used to divide the reference voltage to output the first voltage and the second voltage.

4. The battery charging circuit as described in claim 3, characterized in that, The voltage divider circuit includes a first resistor, a second resistor, and a third resistor; The first end of the first resistor forms the input terminal of the voltage divider circuit and is connected to the power supply circuit to access the reference voltage; The second end of the first resistor and the first end of the second resistor are connected and together form the first output terminal of the voltage divider circuit, which is connected to the first comparison module to output the first voltage; The second end of the second resistor and the first end of the third resistor are connected to form the second output terminal of the voltage divider circuit, which is connected to the second comparator module to output the second voltage; the second end of the third resistor is connected to the power supply ground.

5. The battery charging circuit as described in claim 3, characterized in that, The first comparison module includes a first comparator; The non-inverting input terminal of the first comparator forms the first input terminal of the first comparator module and is connected to the voltage divider circuit to receive the first voltage; The inverting input terminal of the first comparator forms the second input terminal of the first comparison module, which is connected to the temperature detection circuit to receive the first detection voltage; The output terminal of the first comparator constitutes the output terminal of the first comparison module and is connected to the output circuit to output the first signal.

6. The battery charging circuit as described in claim 3, characterized in that, The second comparison module includes a second comparator; The non-inverting input terminal of the second comparator forms the first input terminal of the second comparison module, which is connected to the temperature detection circuit to receive the first detection voltage; The inverting input terminal of the second comparator forms the second input terminal of the second comparison module, which is connected to the voltage divider circuit to receive the second voltage; The output terminal of the second comparator constitutes the output terminal of the second comparison module and is connected to the output circuit to output the second signal.

7. The battery charging circuit as described in claim 1, characterized in that, The power supply circuit includes a charging chip, an inductor, a first capacitor, a second capacitor, a third capacitor, and a fourth capacitor. The charging input voltage terminal of the charging chip and the first terminal of the first capacitor are connected and together form the DC power input terminal of the power supply circuit, so as to be connected to the DC power supply. The low-side FET driver positive power output terminal of the charging chip is connected to the first terminal of the fourth capacitor to form the reference voltage output terminal of the power supply circuit, so as to output the reference voltage. The first switching terminal of the charging chip is connected to the second switching terminal of the charging chip, the first terminal of the second capacitor and the first terminal of the inductor. The second terminal of the second capacitor is connected to the high-side FET driving power supply terminal of the charging chip. The first ground terminal of the charging chip, the second ground terminal of the charging chip, the second terminal of the first capacitor, the second terminal of the third capacitor and the second terminal of the fourth capacitor are all connected to the power supply ground. The battery voltage detection terminal of the charging chip, the second terminal of the inductor, and the first terminal of the third capacitor are connected and together constitute the output DC power terminal of the power supply circuit, which is connected to the battery assembly to output the output DC power. The battery temperature voltage input terminal of the charging chip constitutes the second detection voltage input terminal of the power supply circuit and is connected to the output circuit to receive the second detection voltage.

8. The battery charging circuit as described in claim 1, characterized in that, The output circuit includes a first diode, a second diode, a fourth resistor, and a fifth resistor; The cathode of the first diode forms the first input terminal of the output circuit and is connected to the comparator circuit to receive the first signal; The cathode of the second diode forms the second input terminal of the output circuit, which is connected to the comparator circuit to receive the second signal; The first end of the fourth resistor constitutes the power supply terminal of the output circuit and is connected to the power supply circuit to access the reference voltage. The second end of the fourth resistor, the first end of the fifth resistor, the positive terminal of the first diode, and the positive terminal of the second diode are connected and together form the output terminal of the output circuit, which is connected to the power supply circuit to output the second detection voltage. The second end of the fifth resistor is connected to the power supply ground.

9. The battery charging circuit as described in claim 1, characterized in that, The temperature detection circuit includes a thermistor and a sixth resistor; The first end of the sixth resistor constitutes the power supply terminal of the temperature detection circuit and is connected to the power supply circuit to access the reference voltage. The first end of the thermistor and the second end of the sixth resistor are connected and together form the output terminal of the temperature detection circuit, which is connected to the comparison circuit to output the first detection voltage. The second terminal of the thermistor is connected to the power supply ground.

10. An electronic device, characterized in that, The electronic device includes a battery charging circuit as described in any one of claims 1 to 9.

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