Charging circuit, rechargeable battery and electronic equipment

Abstract

The utility model provides a charging circuit, a rechargeable battery and an electronic device, which are applied to the field of charging safety control, an input end of a charging and discharging control circuit is connected with a charging management circuit and a microcontroller, an output end of the charging and discharging control circuit is connected with the rechargeable battery, and an enable signal of the circuit is sent by the microprocessor. And when the enable signal is a high-level signal, the charging and discharging control circuit conducts the charging management circuit to charge the rechargeable battery, so that the charging process of the rechargeable battery is monitored and managed more comprehensively and more safely. The input end of the path management circuit is connected with the external power supply, and the output end of the path management circuit is connected with the rechargeable battery and the functional circuit of the equipment, so that when the external power supply is powered on, the input voltage of the external power supply can be converted into output low voltage to supply power to the equipment, and the rechargeable battery can be blocked from supplying power; therefore, normal operation of the equipment is ensured when the external high-voltage direct-current power supply is input, and normal charging of the rechargeable battery is ensured. And rapid and efficient charging of the rechargeable battery is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of charging safety control, in particular to a charging circuit, a rechargeable battery and an electronic device. Background Art

[0002] Industrial rechargeable batteries are a type of rechargeable battery that relies on the movement of lithium ions between the positive and negative electrodes to achieve charging and discharging. Its basic principle is the so-called "rocking chair theory", that is, the entry and exit of lithium ions go back and forth between the positive and negative electrodes of the battery, similar to the rocking of a rocking chair. During the charging process, lithium ions are released from the positive electrode material, pass through the electrolyte, and then embed into the negative electrode material; during the discharging process, lithium ions are released from the negative electrode material, pass through the electrolyte again and return to the positive electrode material.

[0003] With the advancement of science and technology and the development of the clean energy industry, rechargeable batteries have become one of the indispensable key components in many fields such as electric vehicles, energy storage systems, and drones. In the prior art, for charging rechargeable batteries, an external adapter is usually used to charge the battery with a constant current; when the battery voltage reaches a preset value, it enters the constant voltage charging stage, at which time the charging voltage remains unchanged and the charging current gradually decreases; when the battery is close to full charge, it enters the floating charge stage, using a small current to maintain the battery charge.

[0004] However, the above method cannot grasp the status of the rechargeable battery in real time, which leads to poor charging safety of the rechargeable battery. Utility Model Content

[0005] The utility model provides a charging circuit, a rechargeable battery and an electronic device, which are used to solve the problem of low charging safety of the rechargeable battery in the prior art.

[0006] In a first aspect, an embodiment of the utility model provides a charging circuit, the charging circuit comprising: a charging management circuit, a charge and discharge control circuit, a path management circuit, and a microcontroller;

[0007] The input end of the charging management circuit is connected to an external power source, the output end of the charging management circuit is connected to the input end of the charging and discharging control circuit, the output end of the charging and discharging control circuit is connected to a rechargeable battery, the input end of the charging and discharging control circuit is also connected to the microcontroller, the input end of the path management circuit is connected to the external power source and the rechargeable battery, and the output end of the path management circuit is connected to a functional circuit of a device;

[0008] The path management circuit is used to convert the input voltage of the external power supply into a low voltage output to power the device when the external power supply is powered on, and block the rechargeable battery from supplying power;

[0009] The charge and discharge control circuit is used to determine to turn on the charge management circuit to charge the rechargeable battery according to the high-level signal sent by the microcontroller received.

[0010] In combination with the first aspect, in some embodiments, the charge and discharge control circuit includes: a load switch;

[0011] The output pin of the microcontroller is connected to the load switch;

[0012] When the signal output by the output pin is a high-level signal, the load switch is turned on and the rechargeable battery is charged;

[0013] When the signal output by the output pin is a low-level signal, the load switch is not turned on and the rechargeable battery stops charging.

[0014] In combination with the first aspect, in some embodiments, the path management circuit includes: a PMOS transistor and a first Schottky diode;

[0015] The positive pole of the external power supply is connected to the anode of the first Schottky diode, the cathode of the first Schottky diode is connected to the gate of the PMOS transistor, the drain of the PMOS transistor is connected to the rechargeable battery, and the source of the PMOS transistor is connected to the functional circuit of the device;

[0016] When the external power supply is powered on, the gate of the PMOS transistor is at a high level, the PMOS transistor is cut off, and the rechargeable battery is blocked from supplying power to the functional circuit;

[0017] When the external power supply is powered off, the gate of the PMOS transistor is at a low level, the PMOS transistor is turned on, and the rechargeable battery is connected to supply power to the functional circuit;

[0018] The first Schottky diode is used to prevent current from flowing back to the external power supply.

[0019] In combination with the first aspect, in some embodiments, the path management circuit further includes: a DC-DC converter and a second Schottky diode;

[0020] The positive pole of the external power supply is connected to the input end of the DC-DC converter, the output end of the DC-DC converter is connected to the anode of the second Schottky diode, and the cathode of the second Schottky diode is connected to the functional circuit;

[0021] When the external power supply is powered on, the DC-DC converter converts the input voltage of the external power supply into the output low voltage and supplies power to the functional circuit through the second Schottky diode;

[0022] The second Schottky diode is used to prevent current backflow into the DC-DC converter.

[0023] In combination with the first aspect, in some embodiments, the charging management circuit includes: a charging management sub-circuit, a first external resistor, a second external resistor, and a filtering capacitor;

[0024] The first ends of the first external resistor and the second external resistor are connected to the battery feedback pin of the charging management sub-circuit. The second end of the first external resistor is connected to the charge and discharge control circuit. The second end of the second external resistor is grounded, and the second external resistor is connected in parallel with the filtering capacitor;

[0025] The input voltage of the external power supply passes through the battery feedback pin and is converted by the first external resistor and the second external resistor to obtain the output high voltage.

[0026] In combination with the first aspect, in some embodiments, the charging management circuit further includes: a third external resistor, a fourth external resistor, and a fifth external resistor;

[0027] The first end of the third external resistor is connected to the negative current detection pin of the charging management sub-circuit. The first end of the fourth external resistor is connected to the positive current detection pin of the charging management sub-circuit. The second end of the third external resistor is connected to the first end of the fifth external resistor. The second end of the fourth external resistor is connected to the second end of the fifth external resistor. The first end of the fifth external resistor is connected to the negative pole of the external power supply, and the second end of the fifth external resistor is grounded;

[0028] The negative current detection pin and the positive current detection pin detect the voltage difference between the first ends of the third external resistor and the fourth external resistor to obtain a stable current;

[0029] The stable current is output through the output pin of the charging management sub-circuit to perform constant current charging on the rechargeable battery.

[0030] In combination with the first aspect, in some embodiments, the charging circuit further includes an ADC charging voltage sampling circuit;

[0031] The input end of the ADC charging voltage sampling circuit is connected to the external power supply, and the output end of the ADC charging voltage sampling circuit is connected to the microcontroller;

[0032] The microcontroller receives the input voltage of the external power supply collected by the ADC charging voltage sampling circuit;

[0033] The microcontroller generates an enable signal according to the input voltage and the status information of the rechargeable battery and sends it to the charge and discharge control circuit. The enable signal includes a high-level signal or a low-level signal.

[0034] In a second aspect, an embodiment of the present invention provides a rechargeable battery, which can be charged by the charging circuit according to any one of the first aspects.

[0035] In combination with the second aspect, in some embodiments, the rechargeable battery includes a power monitoring circuit, which is configured in the protection board circuit inside the rechargeable battery;

[0036] The power monitoring circuit is connected to the microcontroller through the IIC bus and sends the status information of the rechargeable battery to the microcontroller through the IIC bus. The status information includes the power status, battery voltage, and cell temperature.

[0037] In a third aspect, an embodiment of the present invention provides an electronic device, which includes the charging circuit according to any one of the first aspects and the rechargeable battery according to any one of the second aspects.

[0038] The charging circuit, rechargeable battery, and electronic device provided by the present invention connect the input end of the charge and discharge control circuit to the charging management circuit and the microcontroller, and the output end to the rechargeable battery. The enable signal of this circuit is sent by the microprocessor. When the enable signal is a high-level signal, the charge and discharge control circuit turns on the charging management circuit to charge the rechargeable battery, thereby monitoring and managing the charging process of the rechargeable battery more comprehensively and safely. By connecting the input end of the path management circuit to the external power supply and the output end to the rechargeable battery and the functional circuit of the device, when the external power supply is powered on, it can not only convert the input voltage of the external power supply into a low voltage to supply power to the device, but also block the power supply of the rechargeable battery, thus ensuring the normal operation of the device when the external high-voltage DC power supply is input and also ensuring the normal charging of the rechargeable battery. It avoids the situation that when the rechargeable battery has extremely low power and the external DC power supply is input, the device and the rechargeable battery are instantaneously started to charge, resulting in abnormal operation of the charging management circuit. At the same time, when the external power supply is powered on, the path management circuit blocks the discharge circuit of the rechargeable battery and will not consume the electrical energy of the rechargeable battery, maintaining the fast and efficient charging of the rechargeable battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings here are incorporated into the specification and form a part of this specification, showing embodiments that conform to the present invention and are used together with the specification to explain the principles of the present invention.

[0040] Figure 1 A schematic structural diagram of a charging circuit provided for the prior art;

[0041] Figure 2 Schematic diagram of the charging circuit provided by the embodiment of the present utility model;

[0042] Figure 3 Schematic diagram of the charge and discharge control circuit provided by the embodiment of the present utility model;

[0043] Figure 4 Schematic diagram of the path management circuit provided by the embodiment of the present utility model;

[0044] Figure 5 Schematic diagram of the charging management circuit provided by the embodiment of the present utility model;

[0045] Figure 6 Schematic diagram of the ADC charging voltage sampling circuit provided by the embodiment of the present utility model;

[0046] Figure 7 Schematic diagram of the rechargeable battery provided by the embodiment of the present utility model;

[0047] Figure 8 Schematic diagram of the electronic device provided by the embodiment of the present utility model.

[0048] Through the above-mentioned drawings, specific embodiments of the present utility model have been shown, and there will be more detailed descriptions hereinafter. These drawings and textual descriptions are not intended to limit the scope of the concept of the present utility model in any way, but to illustrate the concept of the present utility model to those skilled in the art by referring to specific embodiments. Detailed implementation manners

[0049] To make the objectives, technical solutions, and advantages of the present utility model clearer, the embodiments of the present utility model will be further described in detail below in conjunction with the drawings.

[0050] It should be clear that the described embodiments are only a part of the embodiments of the present utility model, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0051] When the following description involves the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the present utility model. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present utility model as detailed in the appended claims.

[0052] In the description of the present utility model, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to the specific circumstances. In addition, in the description of the present utility model, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previously associated objects are in an "or" relationship.

[0053] Industrial product rechargeable batteries are a type of rechargeable battery that relies on the movement of lithium ions between the positive and negative electrodes to achieve charging and discharging. Its basic principle is the so-called "rocking chair theory", that is, the entry and exit of lithium ions go back and forth between the positive and negative electrodes of the battery, similar to the rocking of a rocking chair. During the charging process, lithium ions are released from the positive electrode material, pass through the electrolyte and then embed into the negative electrode material; during the discharge process, lithium ions are released from the negative electrode material and pass through the electrolyte again to return to the positive electrode material. With the advancement of science and technology and the development of the clean energy industry, rechargeable batteries have become one of the indispensable key components in many fields such as electric vehicles, energy storage systems, and drones. In the prior art, for charging rechargeable batteries, the battery is usually charged with a constant current by an external adapter; when the battery voltage reaches a preset value, it enters the constant voltage charging stage, at which time the charging voltage remains unchanged and the charging current gradually decreases; when the battery is close to full charge, it enters the floating charge stage, and the battery power is maintained with a small current. However, the above method cannot grasp the state of the rechargeable battery in real time, which leads to poor charging safety of the rechargeable battery.

[0054] In view of the above problems, the present utility model provides a charging circuit and an electronic device, thereby realizing the implementation control and detection of charging a rechargeable battery and improving the charging efficiency. Specifically, in the prior art, for charging a rechargeable battery, it is usually charged by an external adapter with a constant current; when the battery voltage reaches a preset value, it enters the constant voltage charging stage, at this time the charging voltage remains unchanged and the charging current gradually decreases; when the battery is nearly fully charged, it enters the floating charge stage to maintain the battery power with a tiny current. However, the above method cannot grasp the state of the rechargeable battery in real time, which leads to poor charging safety of the rechargeable battery. Considering these problems, the inventor studied whether a charge and discharge control circuit could be designed to realize the real-time control of battery charging. At the same time, the enable signal of the charge and discharge control circuit is provided by the sampling values of the power monitor and the external input power analog / digital converter (ADC) and provided after being judged by the microcontroller program logic, which has more comprehensive and safer monitoring and management. And a path management circuit is designed to ensure the normal operation of the device when the external high-voltage power supply outputs and also ensure the normal charging of the rechargeable battery. Based on this, the technical solution of the present utility model is proposed.

[0055] Figure 1 FIG. shows a schematic structural diagram of a charging circuit provided by the prior art, as Figure 1 shown, Figure 1 In the charging circuit, there are two power input ports, VCC and VUSBH, which can provide electrical energy for the charging circuit. VCC is the main power input, while VUSBH is the power introduced from the USB interface or other low-voltage sources and is used to supply power to the circuit under appropriate circumstances. U1 (TP4056X_C2763448) is the core of the circuit. It is a single-cell rechargeable battery charging management IC that can automatically detect the state of the battery and control the charging process. TP4056X supports constant current (CC) and constant voltage (CV) charging modes and can adjust the charging process according to the voltage and current requirements of the battery. BAT and HBAT+ are respectively connected to the positive and negative electrodes of the rechargeable battery. HBAT+ is used to monitor or protect the port on the high-voltage side of the battery. The internal mechanism of the integrated circuit will control the charging current according to the battery voltage and the resistance value of the external resistor to ensure that the battery is charged within a safe range. LED1 is connected to the circuit through R3 and R4 and is used to indicate the charging state. When the battery is charging, LED1 may light up and go out or change color after charging is completed. The capacitors in the circuit play the roles of filtering, decoupling, and stabilizing the power supply, which helps to reduce noise and improve the stability of the circuit. However, this method has a slow charging speed and cannot meet the demand for fast charging. There may also be overvoltage charging, so the charging safety of the battery is relatively low.

[0056] Figure 2The structural schematic diagram of the charging circuit provided by the embodiment of the present utility model is as follows. Figure 2 As shown, the charging circuit includes a charging management circuit, a charge and discharge control circuit, a path management circuit, and a microcontroller.

[0057] The input end of the charging management circuit is connected to an external power supply, the output end of the charging management circuit is connected to the input end of the charge and discharge control circuit, the output end of the charge and discharge control circuit is connected to a rechargeable battery, the input end of the charge and discharge control circuit is also connected to the microcontroller, the input end of the path management circuit is connected to the external power supply, and the output end of the path management circuit is connected to the rechargeable battery and the functional circuit of the device.

[0058] Among them, when the external power supply is powered on, the charging management circuit can determine the charging method according to the input voltage of the external power supply and the power of the rechargeable battery. The charging methods include trickle charging, constant current charging, and constant voltage charging. In order to increase the constant current charging holding time of the rechargeable battery and improve the charging speed, the charging management circuit can convert and output a set voltage (BATFB) from the charging input of the external power supply (POWER IN+ / -). This set voltage is designed to be slightly higher and output to the charge and discharge control circuit.

[0059] Optionally, trickle charging is also known as maintenance charging or compensation charging, which is used to make up for the capacity loss caused by self-discharge after the battery is fully charged. It is usually applied when the battery power is close to full, and the current is very small, close to the self-discharge current during actual use. The advantage of trickle charging is to prevent overcharging of the battery, reduce heat dissipation and damage caused by chemical reactions. In addition, trickle charging can also help the battery maintain the best state and extend the service life of the battery.

[0060] Constant current charging refers to a charging method in which the current remains constant throughout the charging process. When the battery power is low, a stable charging current is set in constant current charging until the battery voltage reaches a preset value or the battery reaches a certain capacity. The main purpose of the constant current stage is to quickly replenish the battery power, which is suitable for the situation where the battery power needs to be restored urgently. The advantage of constant current charging is that the charging current value can be determined according to the capacity of the storage battery, and the charging amount can be directly calculated and the charging completion time can be determined. However, as the battery power increases, the actual received power of the battery will gradually decrease, so the efficiency of constant current charging is relatively low in the later stage.

[0061] Constant voltage charging refers to a charging method in which the voltage between the two poles of the battery is maintained at a constant value. When the battery voltage approaches the maximum voltage limit of the charger, the charger will switch to the constant voltage mode, keep the voltage stable, and continue to supply a small current to the battery until the battery is fully charged. The main purpose of the constant voltage stage is to avoid overcharging, prevent battery damage and safety hazards. The advantage of constant voltage charging is that it automatically adjusts the charging current as the state of charge of the battery changes. If the specified constant voltage value is appropriate, it can not only ensure the full charge of the battery, but also minimize gas evolution and water loss. However, long-term constant voltage charging may cause lead sulfate crystals that are difficult to recover to form inside the battery, reducing the battery capacity.

[0062] The charge and discharge control circuit is used to control the conduction and cut-off of the charging management circuit to set the output voltage, and mainly can realize the real-time management and control of battery charging, and is used to prevent overvoltage charging of the battery and protect the safety of battery charging. The input end of this circuit is connected to the charging management circuit, and the output end is connected to the rechargeable battery. When this circuit is conducting, the rechargeable battery can be normally charged. When this circuit is cut off, the rechargeable battery stops charging.

[0063] The input end of the charge and discharge control circuit is also connected to the microcontroller. The microcontroller can input an enable signal (MCU_Vbat_EN) to the charge and discharge control circuit through a pin. Based on the input voltage of the external power supply and the real-time state information of the battery, the microcontroller judges according to the battery power threshold value set by its program logic and generates an enable signal to send to the charge and discharge control circuit.

[0064] Among them, the enable signal includes a high-level signal or a low-level signal. If the input voltage of the external power supply is high enough (that is, it meets the voltage requirement for charging the battery), and the real-time battery power is lower than the set battery power threshold value, then the battery needs to be charged, and the generated enable signal is a high-level signal; if the above conditions are not met (that is, the input voltage of the external power supply is insufficient or the battery power is not lower than the threshold value), then the battery does not need to be charged, and the generated enable signal is a low-level signal. Through this method, the monitoring and management of battery charging can be realized more comprehensively and safely.

[0065] In order to ensure the normal charging of the rechargeable battery and avoid abnormal operation of the charging management circuit caused by the external power supply input and the instantaneous start of the device and the rechargeable battery charging when the rechargeable battery has extremely low power, the path management circuit is used to ensure that the battery does not consume battery power during charging, and also meets the product requirements of high-voltage input charging, and provides the instantaneous electric energy for device startup.

[0066] Specifically, during charging input, the rechargeable battery can be powered off. This can also prevent the situation where, when the rechargeable battery has extremely low power, the DC charging input has to charge the rechargeable battery and supply power to the entire device system simultaneously, resulting in abnormal overcurrent protection output of the charging management circuit, thus meeting the need for the device with an extremely low-power rechargeable battery to start instantaneously.

[0067] Optionally, the charging circuit may further include an ADC charging voltage sampling circuit. The input end of the ADC charging voltage sampling circuit is connected to an external power supply, and the output end is connected to the microcontroller. This circuit can collect the input voltage of the external power supply for the microcontroller.

[0068] In a possible implementation, in order to be able to monitor the status information of the rechargeable battery in real time, a power monitoring circuit can be set in the rechargeable battery, which can be connected to the protection board circuit included inside the rechargeable battery, for real-time monitoring of the power status, voltage, cell temperature, and other real-time status information of the rechargeable battery PACK, and providing real-time data to the microcontroller through the Inter-Integrated Circuit (IIC) bus.

[0069] Optionally, the power monitoring circuit can also be set in the external circuit of the rechargeable battery. The input end of the power monitoring circuit is connected to the rechargeable battery, and the output end is connected to the microcontroller. Similarly, real-time data can be provided to the microcontroller through the IIC bus.

[0070] It should be noted that the rechargeable battery is the power supply for the device, and an external DC power supply is required to quickly charge it when the battery has low power. The charging current and charging voltage need to be designed within the maximum allowable value of the battery cell to ensure the charging safety of the rechargeable battery.

[0071] Figure 3 The structural schematic diagram of the charge and discharge control circuit provided by the embodiment of the present invention is as Figure 3 shown. The charge and discharge control circuit includes a load switch with controllable enabling, and the microcontroller controls the enabling pin to make it conduct to charge the battery or not conduct to stop charging.

[0072] UP2 is a load switch device, and MCU_Vbat_EN is its enabling pin. When the voltage is high, the load switch conducts to charge Vbat (rechargeable battery); when the voltage is low, the load switch does not conduct and does not charge Vbat. Among them, RP3 is a reserved enabling pull-up resistor, which is used when continuously enabling Vbat charging by default.

[0073] By Figure 3It can be seen that other resistors and capacitor components are also included in the circuit, all of which are used for filtering, decoupling, and stabilizing the power supply, helping to reduce noise and improve the stability of the circuit. Only one connection method of other resistors and capacitor components for circuit protection is shown in the figure, and it can also be other connection methods that can perform circuit protection. The embodiments of the present invention do not make specific limitations.

[0074] Optionally, UP2 therein can be a metal-oxide-semiconductor field-effect transistor (MOSFET) or an integrated load switch device. The embodiments of the present invention do not make specific limitations.

[0075] Figure 4 It is a schematic structural diagram of the path management circuit provided by the embodiments of the present invention. As Figure 4 shown, the path management circuit includes a P-channel metal-oxide-semiconductor field-effect transistor (PMOS) and a first Schottky diode.

[0076] Among them, the positive pole of the external power supply is connected to the anode of the first Schottky diode, the cathode of the first Schottky diode is connected to the gate of the PMOS, the drain of the PMOS is connected to the rechargeable battery, and the source of the PMOS is connected to the functional circuit of the device.

[0077] In order to achieve the operation of zero-power charging of the rechargeable battery and simultaneous startup of the device, when the external power supply POWER1_IN+ is powered on, after passing through the first Schottky diode (DP1), the gate of QP1 (PMOS) is at a high level and does not meet the conduction condition, so QP1 does not conduct, and thus the battery Vbat does not supply power to the subsequent functional circuit; when there is no external power supply, POWER1_IN+ is at a low level, the gate of QP1 is at a low level, and the conduction condition is met, so QP1 conducts. At this time, the battery Vbat outputs power to supply the subsequent functional circuit. Among them, the first Schottky diode is used to prevent current backflow to the external power supply.

[0078] Optionally, the path management circuit further includes a DC-DC converter and a second Schottky diode. The positive pole of the external power supply is connected to the input end of the DC-DC converter, the output end of the DC-DC converter is connected to the anode of the second Schottky diode, and the cathode of the second Schottky diode is connected to the functional circuit.

[0079] In order to achieve high-voltage adapter input and meet the requirements of normal operation of high-voltage input devices, when the external power supply POWER1_IN+ is powered on, the circuit outputs a set voltage value through the DC-DC converter (UP3), and after passing through the second Schottky diode (DP2), a low voltage (Vbat_V) is output to supply power to the subsequent full-functional circuit.

[0080] Optionally, UP3 supports high-voltage input requirements. When applied to this circuit, it can meet the product's high-voltage adapter input product requirements. When DP2 is used when QP1 is turned on and Vbat supplies power, it plays a role in preventing level backflow. This circuit also includes multiple resistors, capacitors, and inductors, all of which are used for filtering, decoupling, and stabilizing the power supply, helping to reduce noise and improve the stability of the circuit. Figure 4 Only one connection method is shown in the figure. The embodiments of the present invention do not specifically limit the connection method of the protection circuit.

[0081] Figure 5 This is a schematic diagram of the structure of the charging management circuit provided by the embodiments of the present invention. As Figure 5 shown, the charging management circuit includes a charging management sub-circuit, a first external resistor, a second external resistor, and a filter capacitor.

[0082] The first ends of the first external resistor (RP13) and the second external resistor (RP17) are connected to the battery feedback pin (BATFB) of the charging management sub-circuit. The second end of RP13 is connected to the charge and discharge control circuit. The second end of RP17 is grounded, and RP17 is connected in parallel with the filter capacitor (CP20).

[0083] Optionally, the charging management circuit further includes a third external resistor, a fourth external resistor, and a fifth external resistor.

[0084] The first end of the third external resistor (RP6) is connected to the current detection negative terminal pin (CSN) of the charging management sub-circuit. The first end of the fourth external resistor (RP11) is connected to the current detection positive terminal pin (CSP) of the charging management sub-circuit. The second end of RP6 is connected to the first end of the fifth external resistor (RP9). The second end of RP11 is connected to the second end of RP9. The first end of RP9 is connected to the negative pole of the external power supply, and the second end of RP9 is grounded.

[0085] The external power supply (POWER IN+) is input and converted by the charging management sub-circuit (charging management component) to output a set voltage (adjust the resistance values of PR13 and RP17). This set voltage will be slightly higher. The purpose of this design is that due to the actual influence of the internal resistance of the rechargeable battery protection board circuit and the internal resistance of the battery cell, when the rechargeable battery is charged using the charging management component, it will prematurely enter the constant voltage mode from the constant current mode, resulting in an extended charging time and unable to meet the time requirements of fast charging.

[0086] The internal resistance of the rechargeable battery protection board is 0.2 Ω, and the constant current charging current is designed to be the maximum allowable current of 2 A. That is, there will be a voltage drop of 0.4 V on the protection board. Therefore, the output set voltage BATFB of the charging management component circuit conversion is designed to be less than or equal to 4.6 V to offset the 0.4 V internal resistance voltage drop on the protection board, thereby preventing the charging management component from entering the constant voltage mode prematurely due to the internal resistance voltage drop of the protection board, and ultimately increasing the holding time of the constant current mode and shortening the charging time.

[0087] During constant current mode charging, to ensure a stable charging current, the voltage difference between the first ends of RP6 and RP11 is detected based on the CSN pin and CSP pin to obtain a stable current, and the stable current is output through the output pin (BAT) of the charging management component to perform constant current charging on the rechargeable battery.

[0088] Optionally, the charging management component can be any component capable of implementing charging management, and the specific type of the charging management component is not specifically limited in the embodiments of the present invention.

[0089] Figure 6 It is a schematic structural diagram of the ADC charging voltage sampling circuit provided by the embodiments of the present invention. As Figure 6 shown, in order to be able to monitor and accurately collect the input voltage of the external power supply in real time, the ADC charging voltage sampling circuit includes a voltage dividing circuit and a filtering circuit, thereby reducing the relatively high charging voltage to the range acceptable to the ADC (analog-to-digital converter) and removing noise through filtering. In this circuit, resistors R6, R5, and R7 and capacitors work together.

[0090] Specifically, the input voltage of the external power supply first passes through resistor R6, and R6 plays a role in limiting current and preliminary voltage division here.

[0091] Then, the current is shunted through resistors R5 and R6. These two resistors together form a voltage divider to reduce the charging voltage to the input range of the ADC. The voltage division ratio is determined by the resistance values of R5 and R6, that is:

[0092]

[0093] Among them, V ADC represents the voltage at the input end of the ADC, that is, the voltage input to the microcontroller, and V CHG represents the input voltage of the external power supply.

[0094] The resistor R7 is connected in parallel with the capacitor, forming an RC low-pass filter, which further removes high-frequency noise and interference from the charging voltage, ensuring that the signal sampled by the ADC is clean and stable. The size of the capacitor and the resistance value of the resistor R7 jointly determine the cut-off frequency of the filter, that is, the highest frequency of the signal allowed to pass through the filter. The voltage signal after voltage division and filtering is sent to the ADC input terminal of the microcontroller.

[0095] The microcontroller periodically samples this voltage signal through its built-in ADC module and converts it into a digital value.

[0096] The microcontroller can monitor the charging voltage based on this digital value and adjust the charging strategy or perform other related operations as needed.

[0097] Figure 7 The structure diagram of the rechargeable battery provided by the embodiment of the present invention is shown in Figure 7 As shown, in order to be able to monitor the state of the rechargeable battery in real time, a power monitoring circuit, that is, a power monitor, is set inside the rechargeable battery. The power monitoring circuit is connected to the inside of the rechargeable battery, and then monitors and collects the state information of the rechargeable battery, and provides real-time data to the microcontroller through the IIC bus.

[0098] Exemplarily, when the power monitor provides the information of the charging percentage of the rechargeable battery pack being 95% detected through its IIC signal interface to the microcontroller, after receiving this information, when the microcontroller judges through its program logic that the set charging threshold is reached, it will directly control the MCU_Vbat_EN signal to output a low level, turn off the UP2 load switch, and stop charging the rechargeable battery, so as to ensure that the charging voltage is lower than the maximum working voltage of the rechargeable battery cell and ensure the charging safety of the rechargeable battery.

[0099] When the power monitor provides the information of the charging percentage of the rechargeable battery pack being 90% detected through its IIC signal interface to the microcontroller, after receiving this information, when the microcontroller judges through its program logic that the set power consumption threshold is reached, it will directly control the MCU_Vbat_EN signal to output a high level, continue to turn on the UP2 load switch, and continue to charge the rechargeable battery, so as to ensure that the voltage of the rechargeable battery maintains a high percentage in the charging state to meet the duration requirement during the subsequent use of the product.

[0100] The MCU_Vbat_EN signal also determines the set threshold for ADC sampling through the program logic of the microcontroller, and detects the ADC voltage value of the external power supply POWER1_IN+. It checks whether the external power supply exists and is supplying power. When it detects that the external power supply POWER1_IN+ exists, and combines with the percentage of the rechargeable battery's power detected by the fuel gauge, such as when the power is 10%, the microcontroller directly controls the MCU_Vbat_EN signal to output a high level, enabling the UP2 load switch to continuously charge the rechargeable battery until it is full.

[0101] Optionally, the IIC bus consists of two bidirectional signal lines, SDA (Serial Data Line) and SCL (Serial Clock Line). For data transmission, when SCL is at a high level, the level change on the SDA line is regarded as valid data. The sending end (rechargeable battery) stabilizes the level of SDA before the rising edge of SCL to represent the bit (0 or 1) to be sent. Data is transmitted in bytes, and the most significant bit (MSB) of each byte is sent first. After sending a byte, usually an acknowledgment bit (ACK / NACK) needs to follow to confirm whether the data has been successfully received. For data reception, the receiving end (microcontroller) reads data from the SDA line when SCL is at a high level. It must ensure that a stable level is read before the falling edge of SCL to avoid data errors. After receiving a byte of data, the receiving end sends an acknowledgment signal (ACK) or a non-acknowledgment signal (NACK) to the sending end to notify the sending end whether the data has been correctly received.

[0102] In IIC communication, the clock signal is generated and controlled by the sending end. The sending end controls the data transmission rate and synchronization through the level change of the SCL line. The high and low level periods on the SCL line determine the data transmission rate. In the standard mode, the bit rate of the IIC bus can reach 100Kbit / s, while in the fast mode and high-speed mode, the rates can be increased to 400Kbit / s and 3.4Mbit / s respectively.

[0103] Figure 8 The structural schematic diagram of the electronic device provided by the embodiment of the present invention is as Figure 8 shown. The electronic device includes the charging circuit in any one of the foregoing embodiments and the rechargeable battery in any one of the foregoing embodiments. The external power supply can be connected to the electronic device, and thus charge the rechargeable battery through the charging circuit in the electronic device.

[0104] Optionally, the electronic device may be a smart electronic device such as a smart phone, a laptop computer, a tablet computer, a wearable device, etc., or a smart home device, or an electric vehicle and an electric bicycle, or industrial products such as an industrial robot, a smart meter and a control device. The specific type and form of the electronic device are not specifically limited in the embodiments of the present invention.

[0105] The above are only the embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, various modifications and changes can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. A charging circuit, characterized in that: The charging circuit includes: a charging management circuit, a charging and discharging control circuit, a path management circuit, and a microcontroller; The input end of the charging management circuit is connected to an external power source, the output end of the charging management circuit is connected to the input end of the charging and discharging control circuit, the output end of the charging and discharging control circuit is connected to a rechargeable battery, the input end of the charging and discharging control circuit is also connected to the microcontroller, the input end of the path management circuit is connected to the external power source and the rechargeable battery, and the output end of the path management circuit is connected to a functional circuit of a device; The path management circuit is used to convert the input voltage of the external power supply into a low voltage output to power the device when the external power supply is powered on, and block the rechargeable battery from supplying power; The charge and discharge control circuit is used to determine to turn on the charging management circuit to charge the rechargeable battery according to the received high-level signal sent by the microcontroller.

2. The circuit according to claim 1, characterized in that The charge and discharge control circuit comprises: a load switch; The output pin of the microcontroller is connected to the load switch; When the signal output by the output pin is a high level signal, the load switch is turned on and the rechargeable battery is charged; When the signal output by the output pin is a low level signal, the load switch is not turned on, and the charging of the rechargeable battery stops.

3. The circuit according to claim 1, characterized in that The path management circuit includes: a P-channel metal oxide semiconductor field effect transistor PMOS tube and a first Schottky diode; The positive electrode of the external power supply is connected to the anode of the first Schottky diode, the cathode of the first Schottky diode is connected to the gate of the PMOS tube, the drain of the PMOS tube is connected to the rechargeable battery, and the source of the PMOS tube is connected to the functional circuit of the device; When the external power supply is powered on, the gate of the PMOS tube is at a high level, the PMOS tube is turned off, and the rechargeable battery is prevented from supplying power to the functional circuit; When the external power supply is powered off, the gate of the PMOS tube is at a low level, the PMOS tube is turned on, and connected to the rechargeable battery to supply power to the functional circuit; The first Schottky diode is used to prevent current from flowing back to the external power supply.

4. The circuit according to claim 3, characterized in that The path management circuit further includes: a DC-DC converter and a second Schottky diode; The positive electrode of the external power supply is connected to the input end of the DC-DC converter, the output end of the DC-DC converter is connected to the anode of the second Schottky diode, and the cathode of the second Schottky diode is connected to the functional circuit; When the external power supply is powered on, the DC-DC converter converts the input voltage of the external power supply into the output low voltage, and supplies power to the functional circuit through the second Schottky diode; The second Schottky diode is used to prevent current from flowing back into the DC-DC converter.

5. The circuit according to claim 1, characterized in that The charging management circuit comprises: a charging management subcircuit, a first external resistor, a second external resistor and a filter capacitor; The first ends of the first external resistor and the second external resistor are connected to the battery feedback pin of the charging management subcircuit, the second end of the first external resistor is connected to the charge and discharge control circuit, the second end of the second external resistor is grounded, and the second external resistor is connected in parallel with the filter capacitor; The input voltage of the external power source is converted through the battery feedback pin, the first external resistor and the second external resistor to obtain an output high voltage.

6. The circuit according to claim 5, characterized in that The charging management circuit further includes: a third external resistor, a fourth external resistor and a fifth external resistor; The first end of the third external resistor is connected to the current detection negative terminal pin of the charging management subcircuit, the first end of the fourth external resistor is connected to the current detection positive terminal pin of the charging management subcircuit, the second end of the third external resistor is connected to the first end of the fifth external resistor, the second end of the fourth external resistor is connected to the second end of the fifth external resistor, the first end of the fifth external resistor is connected to the negative electrode of the external power supply, and the second end of the fifth external resistor is grounded; The current detection negative terminal pin and the current detection positive terminal pin detect a voltage difference between the first end of the third external resistor and the first end of the fourth external resistor to obtain a stable current; The stable current is outputted through the output pin of the charging management subcircuit to perform constant current charging for the rechargeable battery.

7. The circuit according to claim 1, characterized in that The charging circuit also includes an analog / digital converter ADC charging voltage sampling circuit; The input end of the ADC charging voltage sampling circuit is connected to the external power supply, and the output end of the ADC charging voltage sampling circuit is connected to the microcontroller; The microcontroller receives the input voltage of the external power supply collected by the ADC charging voltage sampling circuit; The microcontroller generates an enable signal according to the input voltage and the state information of the rechargeable battery and sends it to the charge and discharge control circuit, and the enable signal includes a high level signal or a low level signal.

8. A rechargeable battery, characterized in that: The rechargeable battery can be charged by the charging circuit according to any one of claims 1 to 7.

9. The battery according to claim 8, characterized in that The rechargeable battery includes a power monitoring circuit, and the power monitoring circuit is configured in a protection board circuit inside the rechargeable battery; The power monitoring circuit is connected to the microcontroller via an integrated circuit IIC bus, and sends status information of the rechargeable battery to the microcontroller via the IIC bus, wherein the status information includes power status, battery voltage, and battery core temperature.

10. An electronic device, characterized in that: The electronic device comprises the charging circuit as claimed in any one of claims 1 to 7 and the rechargeable battery as claimed in any one of claims 8 to 9.

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