Charging control circuit, power supply device and electronic equipment

Abstract

The invention discloses a charging control circuit, a power supply device and electronic equipment, and the circuit comprises a voltage detection module which is used for detecting the voltage of a battery pack and generating a voltage detection signal; the charging detection module is used for detecting the connection state of the charging equipment and the battery pack and generating a charging detection signal; the main control module is used for generating a switch control signal according to the voltage detection signal when the charging detection signal represents that the charging equipment is electrically connected with the battery pack; the charging control module is used for conducting connection or disconnection according to the switch control signal so as to adjust the charging current of the battery pack. The voltage of the battery pack is detected through the voltage detection module, and when it is detected that the charging device and the battery pack are electrically connected, the main control module generates the corresponding switch control signal according to the voltage of the battery pack to control connection or disconnection of the charging control module, so that the magnitude of the charging current of the battery pack is adjusted; the charging safety is improved, and the charging efficiency and the charging effect are ensured.

Description

Technical Field

[0001] The present application relates to the technical field of charging circuits, and in particular to a charging control circuit, a power supply device and an electronic device. Background Art

[0002] Lithium batteries have been widely used in various fields due to their advantages such as high energy density, light weight, no memory effect, and green environmental protection; especially in the fields of electric vehicles, cordless vacuum cleaners and floor scrubbers, lithium batteries have become a popular choice due to their own technological advantages and mature industrial chain.

[0003] However, when using lithium batteries, they are often left idle for a long time when the battery power is relatively low, which can easily lead to undervoltage of the lithium battery, which can cause the lithium battery to malfunction in severe cases. In addition, due to the principle of electrochemistry, lithium batteries are not allowed to be charged with high current when undervoltage, otherwise it is easy to damage the lithium battery.

[0004] One of the current methods for charging undervoltage lithium batteries is to use a charger directly. The charging current will flow directly into the lithium battery. When the lithium battery voltage is very low, the charger voltage will be pulled very low, which can easily cause damage to the charger. Another method is to disassemble the battery pack and then charge a single battery, but the charging process is too cumbersome and requires professionals to disassemble the battery pack. In most cases, the battery needs to be returned to the factory, which increases the use and maintenance costs of the battery. Summary of the invention

[0005] In view of the above problems, the present application provides a charging control circuit, a power supply device and an electronic device to solve the above technical problems.

[0006] In a first aspect, the present application provides a charging control circuit, which includes a main control module and a voltage detection module, a charging detection module and a charging control module electrically connected to the main control module, respectively, the voltage detection module and the charging detection module are also electrically connected to a battery pack, respectively, and the charging control module is connected between a charging device and a battery pack;

[0007] A voltage detection module, used to detect the voltage of the battery pack and generate a voltage detection signal;

[0008] A charging detection module, used to detect the connection status between the charging device and the battery pack and generate a charging detection signal;

[0009] A main control module, used to generate a switch control signal according to a voltage detection signal when the charging detection signal indicates that the charging device and the battery pack are electrically connected;

[0010] The charging control module is used to switch on or off according to the switch control signal to adjust the charging current of the battery pack.

[0011] In a possible implementation of the present application, the main control module is used to:

[0012] If the battery pack voltage corresponding to the voltage detection signal is less than or equal to a preset charging activation threshold voltage, a first switch control signal is generated and output to the charging control module;

[0013] If the battery pack voltage is greater than the charge activation threshold voltage, a second switch control signal is generated and output to the charge control module;

[0014] The second on-time length during which the second switch control signal controls the charging control module to be turned on is greater than the first on-time length during which the first switch control signal controls the charging control module to be turned on.

[0015] In a possible implementation of the present application, the main control module is used to:

[0016] If the battery pack voltage corresponding to the voltage detection signal is less than or equal to a preset charging activation threshold voltage, a first switch control signal is generated and output to the charging control module;

[0017] If the battery pack voltage is greater than the charge activation threshold voltage and less than or equal to the preset trickle charge threshold voltage, a second switch control signal is generated and output to the charge control module;

[0018] If the battery pack voltage is greater than the trickle charge threshold voltage, a third switch control signal is generated and output to the charging control module;

[0019] The second on-time duration of the charging control module controlled by the second switch control signal is greater than the first on-time duration of the charging control module controlled by the first switch control signal and the third on-time duration of the charging control module controlled by the third switch control signal.

[0020] In a possible implementation of the present application, the charging control circuit further includes a charging protection module, the charging protection module is connected between the charging device and the battery pack, and the charging protection module is set to a normally closed state;

[0021] The charging protection module is used to switch from a normally closed state to an open state when the voltage of the battery pack is greater than or equal to a preset charging secondary protection voltage threshold, so as to electrically disconnect the charging device from the battery pack.

[0022] In a possible implementation of the present application, the charging protection module includes a first switch unit and a second switch unit, the first switch unit is connected to the battery pack, and the second switch unit is connected between the charging device and the battery pack;

[0023] A first switch unit is used to monitor the voltage of the battery pack. When the voltage of the battery pack is less than the secondary charging protection voltage threshold, the first switch unit is disconnected; when the voltage of the battery pack is greater than or equal to the secondary charging protection voltage threshold, the first switch unit is turned on;

[0024] The second switch unit is used to be turned on when the first switch unit is turned off, so as to electrically connect the charging device and the battery pack; and to be turned off when the first switch unit is turned on, so as to electrically disconnect the charging device and the battery pack.

[0025] In a possible implementation of the present application, the charging control circuit further includes a temperature detection module electrically connected to the battery pack and the main control module respectively;

[0026] A temperature detection module, used to detect the temperature of the battery pack and generate a temperature detection signal;

[0027] The main control module is used to control the operation of the charging control module according to the temperature detection signal.

[0028] In a possible implementation of the present application, the main control module is used to:

[0029] When the battery pack temperature corresponding to the temperature detection signal is greater than or equal to a preset charging high temperature protection threshold, the charging control module is controlled to disconnect so as to electrically disconnect the charging device from the battery pack;

[0030] When the temperature of the battery pack is lower than a preset charging high temperature protection recovery threshold, the charging control module is controlled to be turned on so as to achieve electrical conduction between the charging device and the battery pack.

[0031] In a possible implementation of the present application, the charging control module includes a third switch unit and a fourth switch unit, the third switch unit is connected between the charging device and the battery pack, and the fourth switch unit is connected to the main control module and the third switch unit;

[0032] a fourth switch unit, configured to be turned on or off according to the switch control signal, and to generate a corresponding first control signal to be output to the third switch unit;

[0033] The third switch unit is used to switch on or off according to the first control signal, and switch the connection state between the charging device and the battery pack to adjust the charging current.

[0034] In a second aspect, the present application also provides a power supply device, which includes a battery pack and the above-mentioned charging control circuit, and the charging control circuit is used to adjust the charging current of the charging device to charge the battery pack.

[0035] In a third aspect, the present application also provides an electronic device, which includes a device body and the above-mentioned charging control circuit or power supply device arranged in the device body.

[0036] From the above content, it can be concluded that the present application has the following beneficial effects:

[0037] In the present application, the voltage of the battery pack is detected by a voltage detection module to generate a corresponding voltage detection signal. When the charging detection module detects that the charging device and the battery pack are electrically connected, the main control module generates a corresponding switch control signal according to the received voltage detection signal to control the conduction or disconnection of the charging control module, thereby adjusting the charging current of the battery pack, avoiding damage to the charging device, improving the safety of charging, saving maintenance costs, and ensuring charging efficiency and charging effect.

[0038] These and other aspects of the present application will become more clearly understood in the description of the following embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 This is a schematic diagram of a first functional module of a charging control circuit provided in an embodiment of the present application;

[0041] Figure 2 It is a schematic diagram of a second functional module of the charging control circuit provided in an embodiment of the present application;

[0042] Figure 3 is a module schematic diagram of a charging protection module provided in an embodiment of the present application;

[0043] Figure 4 This is a schematic diagram of a circuit principle of a charging protection module provided in an embodiment of the present application;

[0044] Figure 5 It is a third functional module schematic diagram of the charging control circuit provided in the embodiment of the present application;

[0045] Figure 6 This is a schematic diagram of a circuit principle of a temperature detection module provided in an embodiment of the present application;

[0046] Figure 7 is a module schematic diagram of a charging control module provided in an embodiment of the present application;

[0047] Figure 8 It is a circuit principle schematic diagram of a charging control module provided in an embodiment of the present application;

[0048] Fig. 9 This is a schematic diagram of a circuit principle of a charging detection module provided in an embodiment of the present application;

[0049] Fig.10 This is a schematic diagram of a circuit principle of a voltage detection module provided in an embodiment of the present application;

[0050] Fig.11 is a fourth functional module schematic diagram of the charging control circuit provided in the embodiment of the present application;

[0051] Fig.12 This is a schematic diagram of a circuit principle of a current detection module provided in an embodiment of the present application;

[0052] Fig.13 It is a functional module diagram of a power supply device provided in an embodiment of the present application;

[0053] Fig.14 It is a schematic diagram of a circuit principle of a power supply device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in this application to clearly and completely describe the technical solutions in this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0055] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0056] In this application, the word "exemplary" is used to mean "used as an example, illustration, or description." Any embodiment described in this application as "exemplary" is not necessarily to be construed as being preferred or advantageous over other embodiments. The following description is given to enable any technician in the field to implement and use the present application. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present application can be implemented without using these specific details. In other instances, well-known structures and processes will not be elaborated in detail to avoid obscuring the description of the present application with unnecessary details. Therefore, the present application is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles and features disclosed in the present application.

[0057] Moreover, the terms "comprises," "comprising," or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0058] It should be noted that in the embodiments of the present application, "connection" can be understood as electrical connection, and the connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be either a direct connection between A and B or an indirect connection between A and B through one or more other electrical components.

[0059] The first pole / first end of each transistor used in the embodiments of the present application is one of the source and the drain, and the second pole / second end of each transistor is the other of the source and the drain. Since the source and drain of the transistor can be symmetrical in structure, the source and drain thereof can be structurally indistinguishable, that is, the first pole / first end and the second pole / second end of the transistor in the embodiments of the present application can be structurally indistinguishable. Exemplarily, in the case where the transistor is a P-type transistor, the first pole / first end of the transistor is the source, and the second pole / second end is the drain; exemplarily, in the case where the transistor is an N-type transistor, the first pole / first end of the transistor is the drain, and the second pole / second end is the source.

[0060] The present application provides a charging control circuit, a power supply device and an electronic device, which are described in detail below.

[0061] First, the present application provides a charging control circuit, such as Figure 1As shown, it is a functional module diagram of a charging control circuit provided in an embodiment of the present application. The charging control circuit 100 may include a main control module 130 and a voltage detection module 110, a charging detection module 120 and a charging control module 140 electrically connected to the main control module 130, respectively. The voltage detection module 110 and the charging detection module 120 are also electrically connected to the battery pack 200, respectively. The charging control module 140 is connected between the charging device 300 and the battery pack 200.

[0062] The voltage detection module 110 can be used to detect the voltage of the battery pack 200 and generate a voltage detection signal; the charging detection module 120 can be used to detect the connection status of the charging device 300 and the battery pack 200 and generate a charging detection signal; the main control module 130 can be used to generate a switch control signal according to the voltage detection signal when the charging detection signal indicates that the charging device 300 and the battery pack 200 are electrically conductive; the charging control module 140 can be used to turn on or off according to the switch control signal to adjust the charging current of the battery pack 200.

[0063] In the embodiment of the present application, the main control module 130 can be any existing type of controller such as a microcontroller unit (MCU), a single-chip microcomputer, etc., which can be connected to the voltage detection module 110, the charging detection module 120 and the charging control module 140 respectively, so as to generate a corresponding switch control signal according to the voltage detection signal to control the state of the charging control module 140.

[0064] The battery pack 200 can be a secondary battery or a rechargeable battery such as a lithium-ion battery, a lead-acid battery, etc., and the charging device 300 can be a charger, a power adapter, etc. that is compatible with the battery pack 200. The charging device 300 can be connected to the AC power output port, and when it is electrically connected to the battery pack 200, it converts the AC power into a charging voltage that is compatible with the battery pack 200, thereby charging the battery pack 200.

[0065] In the embodiment of the present application, the voltage detection module 110 can be electrically connected to the battery pack 200, so as to detect the voltage of the battery pack 200. It can be understood that in some application scenarios, the voltage detection module 110 can detect the voltage of the battery pack 200 at each sampling moment according to a preset sampling frequency, and output the detected voltage detection signal to the main control module 130. In other application scenarios, the voltage detection module 110 can also detect the voltage of the battery pack 200 in response to a detection instruction issued by a user or the main control module 130, so as to output the detected voltage detection signal to the main control module 130.

[0066] The charging detection module 120 can detect the connection status between the charging device 300 and the battery pack 200, generate a charging detection signal and output it to the main control module 130. For example, by default, the charging device 300 is always connected to the main power output port. When the battery pack 200 needs to be charged, the battery pack 200 is connected to the charging device 300. At this time, the charging device 300 and the battery pack 200 are electrically connected. The charging detection module 120 can output a corresponding charging detection signal to the main control module 130 to indicate that the charging device 300 and the battery pack 200 are electrically connected. The charging device 300 charges the battery pack 200 after converting the voltage of the main power. If the charging device 300 is not connected to the battery pack 200, that is, the charging device 300 and the battery pack 200 are electrically disconnected, the charging detection module 120 can also output a corresponding charging detection signal to the main control module 130 to indicate that the charging device 300 and the battery pack 200 are electrically disconnected.

[0067] In an embodiment of the present application, in order to avoid the problem of damaging the charging device 300 by directly charging the battery pack 200 through the charging device 300 when the battery pack 200 is under-voltage, the main control module 130 can generate a switch control signal for controlling the charging current based on the received voltage detection signal, and control the conduction or disconnection of the charging control module 140 connected between the charging device 300 and the battery pack 200 through the switch control signal, thereby adjusting the charging current between the charging device 300 and the battery pack 200.

[0068] In the embodiment of the present application, the voltage of the battery pack 200 is detected by the voltage detection module 110 to generate a corresponding voltage detection signal. When the charging detection module 120 detects that the charging device 300 is electrically connected to the battery pack 200, the main control module 130 generates a corresponding switch control signal according to the received voltage detection signal to control the conduction or disconnection of the charging control module 140, thereby adjusting the charging current of the battery pack 200, avoiding damage to the charging device 300, improving the safety of charging, saving maintenance costs, and ensuring charging efficiency and charging effect.

[0069] Next, continue to Figure 1 The modules shown and the specific implementation methods that may be used in practical applications are described in detail.

[0070] In some embodiments of the present application, the main control module 130 may be used to:

[0071] If the battery pack voltage corresponding to the voltage detection signal is less than or equal to the preset charging activation threshold voltage, a first switch control signal is generated and output to the charging control module 140; if the battery pack voltage is greater than the charging activation threshold voltage, a second switch control signal is generated and output to the charging control module 140; wherein the second switch control signal controls the second on-time of the charging control module 140 to be turned on, which is greater than the first on-time of the charging control module 140 to be turned on by the first switch control signal.

[0072] In the embodiment of the present application, the switch control signal can be a pulse width modulation (PWM) signal. Therefore, the first switch control signal and the second switch control signal can be PWM signals with different duty cycles. Since the second switch control signal controls the second on-time of the charging control module 140 to be turned on to be greater than the first on-time of the charging control module 140 to be turned on to be greater than the first switch control signal, it can be known that the duty cycle of the second switch control signal is greater than the duty cycle of the first switch control signal.

[0073] After receiving the voltage detection signal, the main control module 130 can compare the battery pack voltage corresponding to the voltage detection signal with a preset charging activation threshold voltage. If the battery pack voltage is less than or equal to the charging activation threshold voltage, it can be considered that the current voltage of the battery pack 200 is low and is not suitable for charging it with a large current. Therefore, a first switch control signal with a relatively small duty cycle can be output to control the charging control module 140 to have a shorter on-time within a cycle. For example, the off-time of the charging control module 140 within a cycle is greater than the on-time, thereby ensuring that the charging current is small. The charging current at this time can be considered as an activation current. Charging the low-voltage battery pack 200 with the activation current can protect the battery pack 200, avoid damage, and extend its service life.

[0074] If the battery pack voltage is greater than the charging activation threshold voltage, it can be considered that the current voltage of the battery pack 200 is not low, and it can be charged with a large current to improve the charging efficiency. Therefore, a second switch control signal with a larger duty cycle can be output to control the charging control module 140 to have a longer on time within a cycle. For example, the off time of the charging control module 140 within a cycle is less than the on time, thereby ensuring a larger charging current.

[0075] It can be understood that the charge activation threshold voltage can be determined according to the performance parameters of the battery pack 200 , and the charge activation threshold voltage of different battery packs 200 can be different. It can be specifically determined according to the actual application scenario, which is not limited here.

[0076] In order to ensure fuller charging and avoid the existence of virtual voltage, in some embodiments of the present application, the main control module can be used to:

[0077] If the battery pack voltage corresponding to the voltage detection signal is less than or equal to the preset charging activation threshold voltage, a first switch control signal is generated and output to the charging control module 140; if the battery pack voltage is greater than the charging activation threshold voltage and less than or equal to the preset trickle charging threshold voltage, a second switch control signal is generated and output to the charging control module 140; if the battery pack voltage is greater than the trickle charging threshold voltage, a third switch control signal is generated and output to the charging control module 140.

[0078] The second on-time duration of the charging control module 140 controlled by the second switch control signal is greater than the first on-time duration of the charging control module 140 controlled by the first switch control signal and the third on-time duration of the charging control module 140 controlled by the third switch control signal.

[0079] On the basis of the above-mentioned embodiments, the embodiments of the present application also pre-set a trickle charge threshold voltage. It can be understood that the trickle charge threshold voltage is greater than the charge activation threshold voltage. For example, the charge activation threshold voltage is set to 5%, 8%, etc. of the total voltage, and the trickle charge threshold voltage can be set to 90%, 92%, etc. of the total voltage. It can be set specifically according to actual conditions.

[0080] During the process of the charging device 300 charging the battery pack 200, if the voltage detection module 110 detects that the battery pack voltage is greater than the trickle charging threshold voltage, if a large current is continued to be used to charge the battery pack 200, then when the battery pack 200 is fully charged, there will actually be a virtual voltage, and the voltage value of the fully charged battery pack 200 will drop, resulting in it not actually being fully charged. Therefore, when the battery pack voltage is greater than the trickle charging threshold voltage, the main control module 130 can output a third switch control signal with a smaller duty cycle to control the charging control module 140 to have a shorter on-time within a cycle. For example, the off-time of the charging control module 140 within a cycle is greater than the on-time, thereby ensuring that the charging current is small. The charging current at this time can be considered as a trickle charging current. By charging the battery pack 200 that is about to be fully charged with the trickle charging current, the battery pack 200 can be charged more fully, the existence of virtual voltage can be avoided, and the discharge time of the battery pack 200 can be increased.

[0081] In the embodiment of the present application, when the battery pack voltage is greater than the charge activation threshold voltage and less than or equal to the trickle charge threshold voltage, a large current can be used to charge the battery pack 200. Therefore, the duty cycle of the second switch control signal is relatively large, and the conduction time of the charging control module 140 is relatively long. When the battery pack voltage is less than or equal to the charge activation threshold voltage, and the battery pack voltage is greater than the trickle charge threshold voltage, a small current can be used to charge the battery pack 200. Therefore, the duty cycles of the first switch control signal and the third switch control signal are relatively small.

[0082] It can be understood that in the embodiment of the present application, the duty cycle of the first switch control signal and the duty cycle of the third switch control signal can be the same or different, and both are smaller than the duty cycle of the second switch control signal. The duty cycles of the first switch control signal, the second switch control signal and the third switch control signal can be determined according to the actual application scenario and are not limited here.

[0083] like Figure 2 As shown, in some embodiments of the present application, the charging control circuit 100 may further include a charging protection module 150, which may be connected between the charging device 300 and the battery pack 200, and the charging protection module 150 may be set to a normally closed state.

[0084] The charging protection module 150 can be used to switch from a normally closed state to an open state when the voltage of the battery pack 200 is greater than or equal to a preset secondary charging protection voltage threshold, so as to electrically disconnect the charging device 300 from the battery pack 200 .

[0085] In the embodiment of the present application, the charging protection module 150 is connected between the charging device 300 and the battery pack 200 and is set to a normally closed state. Therefore, when the charging device 300 charges the battery pack 200 through the charging control module 140, it will not affect the normal charging process.

[0086] During the process of charging the battery pack 200 by the charging device 300, the charging protection module 150 can monitor the battery pack voltage in real time. When the battery pack voltage is greater than or equal to the preset charging secondary protection voltage threshold, the charging protection module 150 can be activated and switched from the normally closed state to the disconnected state, thereby disconnecting the charging circuit between the charging device 300 and the battery pack 200 to protect the battery pack 200 from damage due to overvoltage. The battery pack voltage is greater than or equal to the charging secondary protection voltage threshold because the charging control module 140 fails and the charging device 300 continues to charge the battery pack 200. It may also be that there is a problem with the main control module 130. In short, as long as the battery pack voltage is greater than or equal to the charging secondary protection voltage threshold, the charging protection module 150 will cut off the charging circuit between the charging device 300 and the battery pack 200 to protect the battery pack 200.

[0087] like Figure 3 As shown, in some embodiments of the present application, the charging protection module 150 may include a first switch unit 1501 and a second switch unit 1502, wherein the first switch unit 1501 is connected to the battery pack 200, and the second switch unit 1502 is connected between the charging device 300 and the battery pack 200.

[0088] The first switch unit 1501 can be used to monitor the voltage of the battery pack 200. When the voltage of the battery pack 200 is less than the secondary charging protection voltage threshold, the first switch unit 1501 is disconnected; when the voltage of the battery pack 200 is greater than or equal to the secondary charging protection voltage threshold, the first switch unit 1501 is turned on.

[0089] The second switch unit 1502 can be used to be turned on when the first switch unit 1501 is turned off, so as to electrically connect the charging device 300 and the battery pack 200; and to be turned off when the first switch unit 1501 is turned on, so as to electrically disconnect the charging device 300 and the battery pack 200.

[0090] like Figure 4 As shown, in some examples, the first switch unit 1501 may include a sixth transistor Q6, the second switch unit may include a fifth transistor Q5 and a second transistor Q2, and the main circuit structure of the charging protection module 150 is: the base of the sixth transistor Q6 is connected to the voltage monitoring terminal CO of the battery pack 200, the collector of the sixth transistor Q6 is connected to the base of the fifth transistor Q5, the collector of the fifth transistor Q5 is connected to the gate of the second transistor Q2 through the seventh resistor R7, the source of the second transistor Q2 is connected to the first interface P1, the charging device 300 is connected to the first interface P1, and the drain of the second transistor Q2 is connected to the positive terminal BAT+ of the battery pack 200.

[0091] The working principle of the charging protection module 150 is:

[0092] When the battery pack voltage is less than the secondary charging protection voltage threshold, the voltage monitoring terminal CO continuously outputs a low level, and the sixth transistor Q6 is not turned on. At this time, since the charging device 300 charges the battery pack 200, the base voltage of the fifth transistor Q5 is the voltage divided by the sixteenth resistor R16, so the fifth transistor Q5 is turned on and the second transistor Q2 is turned on;

[0093] When the battery pack voltage is greater than or equal to the secondary protection voltage threshold, the voltage monitoring terminal CO outputs a high level. At this time, the sixth transistor Q6 is turned on, and the base of the fifth transistor Q5 is pulled down to the ground potential. The fifth transistor Q5 is not turned on, so that the second transistor Q2 is turned off, thereby realizing the electrical disconnection between the charging device 300 and the battery pack 200, stopping the charging of the battery pack 200, and protecting the battery pack 200 from overvoltage, so as to prevent the battery pack 200 from exploding and catching fire due to overvoltage.

[0094] It can be understood that the secondary protection voltage threshold in the embodiment of the present application can be set to 102%, 105% of the total voltage, etc., which can be specifically determined according to the actual application scenario and is not limited here.

[0095] like Figure 5 As shown, in some embodiments of the present application, the charging control circuit 100 may also include a temperature detection module 160 electrically connected to the battery pack 200 and the main control module 130 respectively; the temperature detection module 160 can be used to detect the temperature of the battery pack 200 and generate a temperature detection signal; the main control module 130 can be used to control the operation of the charging control module 140 according to the temperature detection signal.

[0096] Since the battery pack 200 will generate heat during the charging process, in order to prevent the battery pack 200 from being overheated and damaged, in an embodiment of the present application, the temperature detection module can detect the temperature of the battery pack 200 in real time and generate a corresponding temperature detection signal, so that the main control module 130 can control the charging process of the battery pack 200 by the charging device 300 based on the temperature detection signal.

[0097] The main control module 130 can be specifically used for:

[0098] When the battery pack temperature corresponding to the temperature detection signal is greater than or equal to the preset charging high temperature protection threshold, the charging control module 140 is controlled to disconnect, so that the charging device 300 and the battery pack 200 are electrically disconnected;

[0099] When the temperature of the battery pack is lower than the preset charging high temperature protection recovery threshold, the charging control module 140 is controlled to be turned on, so that the charging device 300 and the battery pack 200 are electrically connected.

[0100] In an embodiment of the present application, the charging high temperature protection threshold and the charging high temperature protection recovery threshold can be set in advance according to the material properties of the battery pack and the actual application scenario. It can be understood that the charging high temperature protection threshold is greater than the charging high temperature protection recovery threshold.

[0101] After obtaining the temperature detection signal, the main control module 130 can compare the battery pack temperature corresponding to the temperature detection signal with the charging high temperature protection threshold and the charging high temperature protection recovery threshold. When the battery pack temperature is greater than or equal to the charging high temperature protection threshold, it can be considered that the temperature of the battery pack 200 is too high. In order to avoid high-temperature charging of the battery pack 200 and damage to the battery cells, the main control module 130 can control the charging control module 140 to disconnect the charging circuit between the charging device 300 and the battery pack 200 and stop charging.

[0102] After charging is stopped, the temperature of the battery pack 200 will gradually decrease. When the battery pack temperature corresponding to the temperature detection signal is less than the charging high temperature protection recovery threshold, it can be considered that the battery pack 200 can be charged again at this time (when the battery pack 200 is not fully charged). Therefore, the main control module 130 can control the charging control module 140 to be turned on, so that the charging device 300 and the battery pack 200 are electrically connected to realize continued charging of the battery pack 200.

[0103] like Figure 6 As shown, in some examples, the temperature detection module 160 may include a negative temperature coefficient thermistor (Negative Temperature Coefficient, NTC), which may be connected to the battery pack 200 and also connected to the twenty-sixth resistor R26, the other end of the twenty-sixth resistor R26 is connected to the battery temperature acquisition terminal BAT_NTC of the main control module 130. It can be understood that as the temperature of the battery pack 200 increases, the resistance of the negative temperature coefficient thermistor decreases, thereby increasing the current flowing through it. The main control module 130 can determine the temperature of the battery pack 200 based on the current of the battery temperature acquisition terminal BAT_NTC, and then control the state of the charging control module 140 to protect the battery pack 200 from high temperature.

[0104] like Figure 7 As shown, in some embodiments of the present application, the charging control module 140 may include a third switch unit 1401 and a fourth switch unit 1402, the third switch unit 1401 is connected between the charging device 300 and the battery pack 200, and the fourth switch unit 1402 is connected to the main control module 130 and the third switch unit 1401.

[0105] The fourth switch unit 1402 may be used to be turned on or off according to the switch control signal, and generate a corresponding first control signal to be output to the third switch unit 1401;

[0106] The third switch unit 1401 can be used to be turned on or off according to the first control signal, and switch the connection state between the charging device 300 and the battery pack 200 to adjust the charging current.

[0107] Specifically, Figure 8 As shown, in some examples, the third switch unit 1401 may include a first transistor Q1, the fourth switch unit 1402 may include a third transistor Q3, and the main structure of the charging control module 140 is: the base of the third transistor Q3 is connected to the output end of the main control module 130 through a ninth resistor R9, for receiving the switch control signal CHR_CONTROL, the collector of the third transistor Q3 is connected to the gate of the first transistor Q1 through a fourth resistor R4, the source of the first transistor Q1 is connected to the first interface P1, and the drain of the first transistor Q1 is connected to the positive terminal BAT+ of the battery pack 200.

[0108] The working principle of the charging control module 140 is:

[0109] When the switch control signal CHR_CONTROL output by the main control module 130 is at a low level, the third transistor Q3 is not turned on. At this time, the end of the fourth resistor R4 connected to the third transistor Q3 is in a high-impedance state, the first transistor Q1 is turned off, and the charging device 300 is electrically disconnected from the battery pack 200; when the switch control signal CHR_CONTROL is at a high level, the third transistor Q3 is turned on. Since the emitter of the third transistor Q3 is grounded, the end of the fourth resistor R4 connected to the third transistor Q3 is grounded, and the gate of the first transistor Q1 is the voltage divided by the fourth resistor R4. The first transistor Q1 is turned on, and the charging device 300 is electrically connected to the battery pack 200, so that the charging device 300 charges the battery pack 200. During the charging process, the switch control signal CHR_CONTROL switches between high and low levels based on its duty cycle, thereby realizing the regulation of the charging current.

[0110] like Fig. 9 As shown, in some examples, the charging detection module 120 may include a fourth transistor Q4, a base of which is connected to the charging circuit between the battery pack 200 and the charging device 300 through a tenth resistor R10, an emitter of the fourth transistor Q4 is grounded, a collector of the fourth transistor Q4 is connected to the charging detection end of the main control module 130, for outputting a charging detection signal DOCK_DET, and connected to the power supply end VCC through a third resistor R3.

[0111] When the charging device 300 is not connected to the battery pack 200 or is electrically disconnected, the fourth transistor Q4 is not turned on, and the charging detection signal DOCK_DET output to the main control module 130 is a high-level signal; when the charging device 300 is electrically connected to the battery pack, the base voltage of the fourth transistor Q4 is the voltage divided by the fourteenth resistor R14, so the fourth transistor Q4 is turned on. Since the emitter of the fourth transistor Q4 is grounded, the charging detection signal DOCK_DET output to the main control module 130 is a low-level signal. Therefore, the main control module 130 can determine the connection status of the charging device 300 and the battery pack 200 according to the high and low levels of the received charging detection signal DOCK_DET.

[0112] like Fig.10 As shown, in some examples, the voltage detection module 110 may include a voltage follower U2A and a twenty-first resistor R21 and a twenty-fourth resistor R24 ​​connected in series, the twenty-first resistor R21 being connected to the positive terminal BAT+ of the battery pack 200, and the connection node of the twenty-first resistor R21 and the twenty-fourth resistor R24 ​​being connected to the in-phase input terminal of the voltage follower U2A through the twenty-third resistor R23, the output terminal of the voltage follower U2A being connected to its inverting input terminal through the twentieth resistor R20, and being connected to the main control module 130 through the twenty-second resistor R22, for outputting a voltage detection signal BAT_VOLTAGE.

[0113] The twenty-first resistor R21 and the twenty-fourth resistor R24 ​​divide the battery pack voltage. The voltage divided by the twenty-fourth resistor R24 ​​is input to the voltage follower U2A through the twenty-third resistor R23, and then output to the main control module 130 by the voltage follower U2A, so that the main control module determines the voltage of the battery pack 200 according to the received voltage detection signal BAT_VOLTAGE.

[0114] like Fig.11 As shown, in some examples, the charging control circuit 100 may further include a current detection module 170, which may be connected to the battery pack 200 and the main control module 130, respectively, to detect the charging current of the battery pack 200, and generate a current detection signal to feed back to the main control module 130; the main control module 130 may be used to determine the size of the charging current based on the current detection signal, and adjust the switch control signal when it is determined that the charging current is inappropriate, thereby adjusting the size of the charging current.

[0115] like Fig.12As shown, the current detection module 170 may include an operational amplifier U1A and multiple peripheral resistors and capacitors, wherein one end of the eleventh resistor R11 is connected to the negative terminal BAT- of the battery pack 200, and the other end is grounded, the inverting input terminal of the operational amplifier U1A is connected to the negative terminal BAT- of the battery pack 200 through the eighth resistor R8, the non-inverting input terminal of the operational amplifier U1A is grounded through the fifteenth resistor R15, and the output terminal of the operational amplifier U1A is connected to the main control module 130 through the thirteenth resistor R13, for outputting the current detection signal BAT_CURRENT.

[0116] In the embodiment of the present application, the current detection module 170 is connected to the negative terminal BAT- of the battery pack 200, and the current of the negative terminal BAT- of the battery pack 200 is sampled through the eighth resistor R8, the eleventh resistor R11 and the fifteenth resistor R15, and the differential is input to the operational amplifier U1A, and the operational amplifier U1A amplifies the differential signal and outputs the corresponding current detection signal BAT_CURRENT to the main control module 130. The main control module 130 can determine the size of the charging current according to the received current detection signal BAT_CURRENT, thereby adjusting the switch control signal to ensure the accuracy of the charging current.

[0117] In a second aspect, the present application also provides a power supply device, such as Fig.13 As shown, the power supply device 1300 may include a battery pack 200 and the above-mentioned charging control circuit 100 , and the charging control circuit 100 is used to adjust the charging current of the charging device 300 to charge the battery pack 200 .

[0118] It should be noted that in the present application, the relevant contents of the charging control circuit 100 correspond to the above one by one, and those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process of the charging control circuit and its corresponding unit modules described above can refer to the following. Figures 1 to 12 The description of the charging control circuit in any embodiment will not be repeated here.

[0119] Since the power supply device 1300 is provided with the charging control circuit of the above-mentioned embodiment, it has all the beneficial effects of the charging control circuit in any of the above-mentioned embodiments, which will not be described in detail here.

[0120] In a third aspect, the present application further provides an electronic device, which includes a device body and the above-mentioned charging control circuit 100 or power supply device 1300 arranged in the device body.

[0121] The electronic device may be a device powered by a lithium battery, such as an electric car, a smart wearable device, or a smart home device.

[0122] Among them, smart wearable devices include but are not limited to smart watches, smart bracelets, and cervical massagers. Smart home devices include but are not limited to smart rice cookers, smart sweepers, smart lights, wireless vacuum cleaners, floor scrubbers, etc.

[0123] Since the electronic device is provided with the charging control circuit of the above embodiment, it has all the beneficial effects of the charging control circuit in any of the above embodiments, which will not be described in detail here.

[0124] The technical solution of the present application is described below in conjunction with some specific application scenarios to facilitate understanding.

[0125] Application scenario 1

[0126] If the vacuum cleaner at home is not used for a long time, the power supply device of the vacuum cleaner needs to be charged. The power supply device integrates a battery pack and a charging control circuit, such as Fig.14 As shown, the charging device is an adapter connected to the mains. After the power supply device is connected to the adapter, the charging circuit of the charging device and the battery pack is turned on, the base of the fourth transistor Q4 is at a high level, and the fourth transistor Q4 is turned on, so that the charging detection module outputs a low-level charging detection signal to the main control module. The main control module then determines that the current voltage of the battery pack is less than the charging activation threshold voltage based on the received voltage detection signal BAT_VOLTAGE. Therefore, the main control module outputs a switch control signal CHR_CONTROL with a smaller duty cycle to the base of the third transistor Q3, and controls the on or off of the first transistor Q1 by controlling the on or off of the third transistor Q3, so that the on time of the first transistor Q1 in one cycle is less than the off time, ensuring that the average current connected to the battery pack is the activation current I0, and charging the low-voltage battery pack with a small current, protecting the battery pack, avoiding damage to the battery pack, and extending the service life of the battery pack.

[0127] When charging continues until the voltage of the battery pack is equal to the preset secondary charging protection voltage threshold, the voltage monitoring terminal CO outputs a high level, and the sixth transistor Q6 is turned on in response to the high level, pulling the base of the fifth transistor Q5 down to the ground potential, and the fifth transistor Q5 is turned off, thereby turning off the second transistor Q2, so that the charging device is electrically disconnected from the battery pack, charging stops, and the battery pack 200 is protected from overvoltage.

[0128] Application scenario 2

[0129] The user charges the lithium battery pack when the battery pack voltage of the electric vehicle remains at 50%. After the charging detection module determines that the lithium battery pack is electrically connected to the charging device, the main control module determines that the current voltage of the lithium battery pack is greater than the charging activation threshold voltage based on the received voltage detection signal BAT_VOLTAGE. Therefore, the main control module outputs a switch control signal CHR_CONTROL with a larger duty cycle to the base of the third transistor Q3, and controls the conduction or disconnection of the first transistor Q1 by controlling the conduction or disconnection of the third transistor Q3, so that the conduction time of the first transistor Q1 in one cycle is greater than the off time, thereby ensuring high-current and efficient charging.

[0130] During the charging process, the temperature detection module continuously detects the temperature of the lithium battery pack. When the temperature of the lithium battery pack is greater than the charging high temperature protection threshold, the main control module controls the charging control module to disconnect, so that the charging device and the lithium battery pack are electrically disconnected, charging is stopped, and high temperature damage to the battery cells is avoided; when the temperature of the lithium battery pack drops to the charging high temperature protection recovery threshold, the main control module controls the charging control module to turn on, so that the charging device continues to charge the lithium battery pack.

[0131] When the voltage of the lithium battery pack reaches the trickle charge threshold voltage, the main control module reduces the duty cycle of the switch control signal so that the average current connected to the lithium battery pack is the trickle charge current I1. The small current continues to charge the lithium battery pack, making the battery pack more fully charged, avoiding the existence of virtual voltage, and increasing the discharge time of the battery pack.

[0132] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the detailed description of other embodiments above, and will not be repeated here.

[0133] In specific implementation, the above units or structures can be implemented as independent entities, or can be arbitrarily combined to be implemented as the same or several entities. The specific implementation of the above units or structures can refer to the previous embodiments and will not be repeated here.

[0134] The above is a detailed introduction to a charging control circuit, a power supply device and an electronic device provided by the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The above description is only used to help understand the circuit and its core idea of ​​the present application. At the same time, for technicians in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A charging control circuit, characterized in that: It includes a main control module, and a voltage detection module, a charging detection module and a charging control module electrically connected to the main control module respectively, the voltage detection module and the charging detection module are also electrically connected to the battery pack respectively, and the charging control module is connected between the charging device and the battery pack; The voltage detection module is used to detect the voltage of the battery pack and generate a voltage detection signal; The charging detection module is used to detect the connection status between the charging device and the battery pack and generate a charging detection signal; The main control module is used to generate a switch control signal according to the voltage detection signal when the charging detection signal indicates that the charging device and the battery pack are electrically connected; The charging control module is used to switch on or off according to the switch control signal to adjust the charging current of the battery pack.

2. The charging control circuit according to claim 1, characterized in that: The main control module is used for: If the battery pack voltage corresponding to the voltage detection signal is less than or equal to a preset charging activation threshold voltage, a first switch control signal is generated and output to the charging control module; If the battery pack voltage is greater than the charging activation threshold voltage, a second switch control signal is generated and output to the charging control module; The second on-time length of the charging control module controlled by the second switch control signal is greater than the first on-time length of the charging control module controlled by the first switch control signal.

3. The charging control circuit according to claim 1, characterized in that: The main control module is used for: If the battery pack voltage corresponding to the voltage detection signal is less than or equal to a preset charging activation threshold voltage, a first switch control signal is generated and output to the charging control module; If the battery pack voltage is greater than the charge activation threshold voltage and less than or equal to a preset trickle charge threshold voltage, a second switch control signal is generated and output to the charge control module; If the battery pack voltage is greater than the trickle charge threshold voltage, a third switch control signal is generated and output to the charging control module; Among them, the second on-time length of the charging control module controlled by the second switch control signal is greater than the first on-time length of the charging control module controlled by the first switch control signal and the third on-time length of the charging control module controlled by the third switch control signal.

4. The charging control circuit according to claim 1, characterized in that: The charging control circuit further includes a charging protection module, which is connected between the charging device and the battery pack, and is set to a normally closed state; The charging protection module is used to switch from a normally closed state to an open state when the voltage of the battery pack is greater than or equal to a preset secondary charging protection voltage threshold, so as to electrically disconnect the charging device from the battery pack.

5. The charging control circuit according to claim 4, characterized in that: The charging protection module includes a first switch unit and a second switch unit, the first switch unit is connected to the battery pack, and the second switch unit is connected between the charging device and the battery pack; The first switch unit is used to monitor the voltage of the battery pack. When the voltage of the battery pack is less than the secondary charging protection voltage threshold, the first switch unit is disconnected; when the voltage of the battery pack is greater than or equal to the secondary charging protection voltage threshold, the first switch unit is turned on; The second switch unit is used to be turned on when the first switch unit is turned off, so as to electrically connect the charging device and the battery pack; And the first switch unit is turned off when it is turned on, so as to electrically disconnect the charging device from the battery pack.

6. The charging control circuit according to claim 1, characterized in that: The charging control circuit also includes a temperature detection module electrically connected to the battery pack and the main control module respectively; The temperature detection module is used to detect the temperature of the battery pack and generate a temperature detection signal; The main control module is used to control the operation of the charging control module according to the temperature detection signal.

7. The charging control circuit according to claim 6, characterized in that: The main control module is used for: When the battery pack temperature corresponding to the temperature detection signal is greater than or equal to a preset charging high temperature protection threshold, the charging control module is controlled to disconnect so as to electrically disconnect the charging device from the battery pack; When the temperature of the battery pack is lower than a preset charging high temperature protection recovery threshold, the charging control module is controlled to be turned on so as to achieve electrical conduction between the charging device and the battery pack.

8. The charging control circuit according to claim 1, characterized in that: The charging control module includes a third switch unit and a fourth switch unit, the third switch unit is connected between the charging device and the battery pack, and the fourth switch unit is connected to the main control module and the third switch unit; The fourth switch unit is used to be turned on or off according to the switch control signal, and to generate a corresponding first control signal to be output to the third switch unit; The third switch unit is used to be turned on or off according to the first control signal, and to switch the connection state between the charging device and the battery pack to adjust the charging current.

9. A power supply device, characterized in that: It comprises a battery pack and a charging control circuit as described in any one of claims 1 to 8, wherein the charging control circuit is used to adjust the charging current of a charging device to charge the battery pack.

10. An electronic device, characterized in that: The electronic device comprises a device body and a charging control circuit as described in any one of claims 1 to 8 or a power supply device as described in claim 9, which is arranged on the device body.

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