Isolation charger voltage range identification circuit, identification method and charger

Abstract

The invention belongs to the technical field of circuit protection, and provides an isolation charger voltage range identification circuit, an identification method and a charger, the circuit comprises a voltage-regulator tube Z1, a voltage-regulator tube Z2, a triode Q1, an optocoupler OC1, a microcontroller MCU and an MOS tube Q2; when the charger is connected, rated charging voltage is output between the positive electrode and the negative electrode of the charger, when the charging voltage of the charger is within an appropriate range, the microcontroller MCU, in a dormant state, of a part of circuits of the protection board BMS can be activated, the activated microcontroller MCU identifies the connection of the charger, and then judges the voltage range of the charger. And if the protection plate BMS judges that the voltage of the charger is qualified, allowing the charger to charge the lithium battery product, otherwise, not allowing the charger to charge the lithium battery product. The voltage identification circuit has an isolation function, and when the charger has abnormal conditions such as high-voltage overcurrent, the protection board BMS is not damaged.

Description

Technical Field

[0001] This application belongs to the technical field of circuit protection, and particularly relates to an isolation charger voltage range identification circuit, an identification method, and a charger. Background Art

[0002] In the circuit design of the lithium battery industry, general protection boards can be divided into high-side MOS solutions and bottom-side MOS solutions. The bottom-side MOS solution is widely used due to advantages such as low cost, mature solution, and high reliability. Currently, due to the presence of chargers with different specifications on the market, users are prone to using inappropriate chargers to charge battery products, resulting in damage to lithium batteries and even accidents such as fires and explosions. The requirements for chargers in lithium battery products have been raised to a higher level, that is, it is necessary to judge the charger voltage range. For chargers outside the specified voltage range, it is not allowed to charge lithium battery products, thereby protecting lithium battery products. The bottom-side MOS solution has the following problems in the charger voltage judgment function. First, it does not have an isolation function and is prone to over-stress damage to the circuit. Second, the negative poles of the charger and the battery are not grounded together, and the voltage range judgment is inaccurate. Summary of the Invention

[0003] Aiming at the defects of the above-mentioned prior art, this application provides an isolation charger voltage range identification circuit, an identification method, and a charger, which can be executed and completed only in part of the circuit of the protection board BMS. When the charger is connected, a rated charging voltage is output between the positive and negative poles of the charger. When the charging voltage of the charger is within a suitable range, the microcontroller MCU in the dormant state of the protection board BMS part of the circuit can be activated. After activation, the microcontroller MCU performs the identification of the charger connection and then judges the charger voltage range. If the protection board BMS judges that the charger voltage is qualified, the bottom-side MOS is turned on to allow the charger to charge the lithium battery product. If it is judged that the charger voltage is unqualified, the bottom-side MOS is kept closed and it is not allowed to charge the lithium battery product. This voltage identification circuit has an isolation function and will not damage the protection board BMS even when abnormal situations such as high voltage and overcurrent occur in the charger.

[0004] In the first aspect, this application provides an isolation charger voltage range identification circuit, and the circuit includes: a voltage stabilizing diode Z1, a voltage stabilizing diode Z2, a triode Q1, an optocoupler OC1, a microcontroller MCU, and a MOS transistor Q2; One end of the voltage stabilizing diode Z1 is connected to the positive electrode of the battery cell, and the other end is connected to the collector of the triode Q1; One end of the voltage stabilizing diode Z2 is connected to the positive electrode of the battery cell, and the other end is connected to the base of the triode Q1; The collector of the triode Q1 is connected to the optocoupler OC1, and the other end of the optocoupler OC1 is connected to the microcontroller MCU; The microcontroller MCU is connected to the negative electrode of the battery cell through the MOS transistor Q2; Among them, the zener diode Z1 is used to set the lower limit voltage of the charger, the zener diode Z2 is used to set the upper limit voltage of the charger, and the voltage regulation value of the zener diode Z2 needs to be higher than that of the zener diode Z1.

[0005] A resistor R2 is also connected between the zener diode Z1 and the collector of the triode Q1.

[0006] A resistor R3 is also connected between the zener diode Z2 and the base of the triode Q1; The base of the triode Q1 is also connected to a resistor R4, and the other end of the resistor R4 is connected to the emitter of the triode Q1; the emitter of the triode Q1 is also connected to the positive terminal of the diode D1; the positive terminal of the diode D1 is also connected to the optocoupler OC1; The negative terminal of the diode D1 is connected to the source of the MOS transistor Q2.

[0007] The optocoupler OC1 is connected to the microcontroller MCU through a resistor R1 and a resistor R5 respectively; The other end of the resistor R5 is also grounded; The microcontroller MCU is used to detect the WK_ID signal of the optocoupler OC1.

[0008] The optocoupler OC1 is connected to the microcontroller MCU through a resistor R1 and a resistor R5 respectively; The other end of the resistor R5 is also grounded; The microcontroller MCU is used to detect the WK_ID signal of the optocoupler OC1.

[0009] The source of the MOS transistor Q2 is also used to connect to the negative terminal of the charger; The gate of the MOS transistor Q2 is connected to the microcontroller MCU; The drain of the MOS transistor Q2 is connected to the negative electrode of the battery cell.

[0010] In a second aspect, the present application also provides an isolation charger voltage range identification method, and the identification method includes: When a charger is connected, if the charger voltage is higher than the voltage regulation value of the zener diode Z1 and lower than the voltage regulation value of the zener diode Z2, then the zener diode Z1 is in a voltage regulation state, the zener diode Z2 is not in a voltage regulation state, the charger voltage is within a suitable range, the optocoupler OC1 is turned on, at this time WK_ID is pulled high to a high level by the resistor R1, and there is an activation action on the microcontroller MCU; the activated microcontroller MCU detects the WK_ID signal; If the WK_ID signal continuously remains at a high level, it is determined that the charger is connected and the charger voltage is within an appropriate range. Then, the microcontroller MCU outputs a signal to drive the MOS transistor Q2, allowing the charger to charge the battery pack. During charging, the voltage of the battery pack will slowly rise. If during the charging process, the voltage of the battery pack is higher than the regulated voltage value of the voltage regulator diode Z2, there will be current flowing through the resistor R3 and the resistor R4 in the voltage regulator diode Z2 in the regulated state. Then, the triode Q1 conducts and shorts the internal diode of the optocoupler OC1, making the optocoupler OC1 non-conductive. At this time, WK_ID is pulled low to a low level by the resistor R5. Based on the WK_ID signal, the microcontroller MCU determines that the charger voltage is not within the appropriate range at this time, stops outputting a signal to drive the MOS transistor Q2, and prohibits the charger from charging the battery pack.

[0011] Preferably, the identification method further includes: When a charger is connected and the charger voltage is higher than the regulated voltage values of both the voltage regulator diode Z1 and the voltage regulator diode Z2, both the voltage regulator diode Z1 and the voltage regulator diode Z2 are in the regulated state. If the charger voltage exceeds the appropriate voltage range, there will be current flowing through the resistor R3 and the resistor R4 in the voltage regulator diode Z2 in the regulated state. Then, the triode Q1 conducts and shorts the internal diode of the optocoupler OC1, making the optocoupler OC1 non-conductive. At this time, WK_ID is pulled low to a low level by the resistor R5, and there is no activation action on the microcontroller MCU. The microcontroller does not need to execute the action of judging the charger voltage.

[0012] Preferably, the identification method further includes: When a charger is connected and the charger voltage is lower than the regulated voltage values of both the voltage regulator diode Z1 and the voltage regulator diode Z2, neither the voltage regulator diode Z1 nor the voltage regulator diode Z2 is in the regulated state. If the charger voltage is lower than the appropriate voltage range, the optocoupler OC1 is non-conductive. At this time, WK_ID is pulled low to a low level by the resistor R5, and there is no activation action on the microcontroller MCU. The microcontroller does not need to execute the action of judging the charger voltage.

[0013] Preferably, the identification method further includes: When no charger is connected, neither the voltage regulator diode Z1 nor the voltage regulator diode Z2 is in the regulated state, and the optocoupler OC1 is non-conductive. At this time, WK_ID is pulled low to a low level by the resistor R5, and there is no activation action on the microcontroller MCU. The microcontroller does not need to execute the action of judging the charger voltage.

[0014] In a third aspect, the present application also provides a charger, and the charger uses an isolation charger voltage range identification circuit as described in the first aspect to identify the isolation charger voltage range.

[0015] Compared with the prior art, the beneficial effects of the present application are as follows: An isolation charger voltage range identification circuit, identification method, and charger proposed in this application. The charger voltage judgment circuit has an isolation function to prevent the negative electrode of the lithium battery product from being pulled up to the same high voltage as the positive electrode by the charger when the charging protection is triggered, resulting in damage to the interface judgment circuit. At the same time, it can be compatible with most charger models on the market without additional modification to the charger, effectively reducing charging accidents caused by incompatible chargers. Further, the identification circuit described in this application adds a charger access activation function. After the charger is connected, the battery is activated, and the battery identifies and judges the charger. Only when the charger voltage is within the qualified range is the charger allowed to perform a charging operation on the battery. It accurately judges the voltage range of the charger and only allows chargers within the appropriate voltage range to charge the lithium battery product. Moreover, the optocoupler OC1 and diode D1 used in the voltage identification circuit described in this application form an isolation protection circuit, and when abnormal situations such as high voltage and overcurrent occur in the charger, it will not cause damage to the protection board BMS. Brief Description of the Drawings

[0016] Figure 1 It is a circuit diagram of a BMS dual protection circuit in an embodiment of this application. Detailed Embodiments

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions will be clearly and completely described below in conjunction with the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts shall fall within the protection scope of this application.

[0018] Embodiment 1: As shown in the attached Figure 1 figure, the left block diagram is the partial circuit of the protection board BMS. The right block diagram is the positive and negative poles of the charger interface. By using components such as a voltage stabilizing diode, MOS transistor, optocoupler, and microcontroller MCU, the identification and judgment of the charger voltage are realized, thereby ensuring the safety of the battery during the charging process.

[0019] Specifically, this application provides an isolation charger voltage range identification circuit, and the circuit includes: a voltage stabilizing diode Z1, a voltage stabilizing diode Z2, a triode Q1, an optocoupler OC1, a microcontroller MCU, and a MOS transistor Q2; One end of the voltage stabilizing diode Z1 is connected to the positive electrode of the battery cell, and the other end is connected to the collector of the triode Q1; One end of the voltage stabilizing diode Z2 is connected to the positive electrode of the battery cell, and the other end is connected to the base of the triode Q1; The voltage stabilizing diodes Z1 and Z2 are respectively connected to the collector and base of the triode Q1, and the working state of the triode Q1 is controlled to transmit the charger voltage information.

[0020] The collector of the triode Q1 is connected to the optocoupler OC1, and the other end of the optocoupler OC1 is connected to the microcontroller MCU; The microcontroller MCU is connected to the negative electrode of the battery cell through the MOS transistor Q2; Among them, two zener diodes Z1 and Z2 are used to set the range of the charger voltage. The zener diode Z1 is used to set the lower limit voltage of the charger, and the zener diode Z2 is used to set the upper limit voltage of the charger. The breakdown voltage value of the zener diode Z2 needs to be higher than that of the zener diode Z1.

[0021] The microcontroller MCU judges whether the voltage of the charger is within a reasonable range by reading the information from the optocoupler OC1. If the voltage meets the requirements, the MCU activates the MOS transistor Q2 to allow the charger to charge the battery. If the voltage does not meet the requirements, the MCU turns off the MOS transistor Q2 to prevent the battery from being charged, thereby preventing damage to the battery.

[0022] The recognition circuit described in this application can be executed and completed only in a partial circuit of the battery management system (BMS) protection board. When the charger is connected, a rated charging voltage is output between the positive and negative electrodes of the charger. When the charging voltage of the charger is within an appropriate range, the microcontroller MCU in the dormant state in the partial circuit of the BMS protection board can be activated. After activation, the microcontroller MCU performs the recognition of the charger connection and then judges the voltage range of the charger. If the BMS protection board judges that the charger voltage is qualified, it turns on the MOS transistor Q2 to allow the charger to charge the lithium battery product. If it judges that the charger voltage is unqualified, it keeps the MOS transistor Q2 off and does not allow the charger to charge the lithium battery product. This voltage recognition circuit has an isolation function, and when abnormal conditions such as high voltage and overcurrent occur in the charger, it will not damage the BMS protection board.

[0023] A resistor R2 is also connected between the zener diode Z1 and the collector of the triode Q1.

[0024] A resistor R3 is also connected between the zener diode Z2 and the base of the triode Q1; Among them, the resistor R2 is connected between the zener diode Z1 and the collector of the triode Q1 and is used to regulate the current flow of the circuit; the resistor R3 is connected between the zener diode Z2 and the base of the triode Q1 and is used to stabilize the operation of the triode Q1.

[0025] The base of the triode Q1 is also connected to a resistor R4, and the other end of the resistor R4 is connected to the emitter of the triode Q1, which plays a role in stabilizing and regulating the working state of the triode Q1 to ensure reasonable triggering conditions for the triode Q1; the emitter of the triode Q1 is also connected to the positive terminal of a diode D1; the positive terminal of the diode D1 is also connected to an optocoupler OC1, and the charging voltage transmission signal is transmitted to the microcontroller MCU through the optocoupler OC1, ensuring that the battery management system (BMS) can monitor and correctly identify the change in the charging voltage; The negative terminal of the diode D1 is connected to the source of the MOS transistor Q2.

[0026] The optocoupler OC1 is respectively connected to the microcontroller MCU through a resistor R1 and a resistor R5; The other end of the resistor R5 is also grounded; The microcontroller MCU is used to detect the WK_ID signal of the optocoupler OC1.

[0027] The optocoupler OC1 is respectively connected to the microcontroller MCU through a resistor R1 and a resistor R5; The other end of the resistor R5 is also grounded; The microcontroller MCU is used to detect the WK_ID signal of the optocoupler OC1.

[0028] The source of the MOS transistor Q2 is also used to connect to the negative terminal of the charger; The gate of the MOS transistor Q2 is connected to the microcontroller MCU; The drain of the MOS transistor Q2 is connected to the negative electrode of the battery cell.

[0029] The circuit of this application enhances the accuracy of charging voltage range recognition and protection functions by adding a diode D1, an optocoupler OC1, multiple resistors, and the control method of the MOS transistor Q2. The microcontroller MCU accurately judges the compliance of the charging voltage by detecting the WK_ID signal of the optocoupler OC1 to ensure safe charging of the battery. At the same time, the isolation measures added in the design (such as the diode D1 and the optocoupler OC1) effectively isolate the abnormal fluctuations of the charger voltage, can effectively prevent unregulated chargers from overcharging lithium battery products, protect the use of lithium battery products, and can judge and identify both the commonly used constant-output chargers and pulse chargers in the market. No additional modification is required for the charger interface, and no additional signal lines need to be added to the interface. When the charger is connected for charging, the lithium battery product can also be activated to judge the connection of the charger. On the basis of not changing the charger and the charger interface, the recognition of charger insertion and voltage range judgment can be realized. By adopting an isolation method, it can prevent damage to the charger and the interface circuit when the bottom MOS scheme triggers protection, playing a protective role.

[0030] Embodiment 2: The present application also provides a method for identifying the voltage range of an isolated charger, and the identification method includes: When a charger is connected, if the charger voltage is higher than the regulated voltage value of the voltage regulator diode Z1 and lower than the regulated voltage value of the voltage regulator diode Z2, then the voltage regulator diode Z1 is in a regulated state to ensure that the charging voltage does not exceed a specific value, avoiding damage to the battery caused by excessive voltage. Since the charging voltage is within a suitable range, the function of Z2 is temporarily ignored and Z2 is not in a regulated state. When the charger voltage is within a suitable range, the optocoupler OC1 conducts, and at this time, WK_ID is pulled high to a high level by the resistor R1, which has an activating effect on the microcontroller MCU; the activated microcontroller MCU detects the WK_ID signal; it is ensured that only when the charger voltage is within a suitable range, the optocoupler OC1 conducts, and the microcontroller MCU will be activated to start subsequent control and detection. This design can effectively protect the battery and the circuit from the influence of excessive or too low voltage.

[0031] If the WK_ID signal continuously maintains a high level state, it is determined that the charger is connected and the charger voltage is within a suitable range, then the microcontroller MCU outputs a signal to drive the MOS transistor Q2. When the MOS transistor Q2 conducts, the circuit between the battery cell group and the charger is closed, and the charger starts to charge the battery cell group, allowing the charger to charge the battery cell group; the charger starts to transfer electrical energy to the battery cell group to charge it. During the whole process, the MCU will monitor the charging state to ensure that the voltage and charging state of the battery cell group are normal.

[0032] During charging, the voltage of the battery cell group will slowly rise. If during the charging process, the voltage of the battery cell group is higher than the regulated voltage value of the voltage regulator diode Z2, there is current flowing through the resistors R3 and R4 in the voltage regulator diode Z2 in a regulated state, and the voltage division of the resistors R3 and R4 provides conditions for the conduction of the triode Q1, then the triode Q1 conducts. After the triode Q1 conducts, it will short-circuit the internal diode of the optocoupler OC1, resulting in the non-conduction of the photodiode of the optocoupler OC1. This means that there will be no response at the output end of the optocoupler OC1. Because the output end of the optocoupler OC1 is not conducting, the WK_ID signal is pulled low to a low level by the resistor R5. At this time, the WK_ID signal indicates that the charger voltage has exceeded the safe charging voltage range. The microcontroller MCU judges according to the WK_ID signal that the charger voltage is not within a suitable range at this time, and stops outputting a signal to drive the MOS transistor Q2. Once the MOS transistor Q2 no longer receives the driving signal, it will turn off, causing the circuit between the charger and the battery cell group to disconnect, thus stopping the charging. By detecting whether the voltage of the battery cell group exceeds the suitable range, it is ensured that the charger will not continue to charge the battery cell group, thereby protecting the battery cell group from the harm of overvoltage charging.

[0033] Preferably, the identification method further includes: When a charger is connected, the charger voltage is higher than the regulated voltages of Zener diode Z1 and Zener diode Z2. Then both Zener diode Z1 and Zener diode Z2 are in the regulated state, indicating that the voltage provided by the charger has exceeded the regulated voltages of Zener diode Z1 and Z2, and the charger voltage starts to enter a state beyond the appropriate range.

[0034] When the charger voltage exceeds the appropriate voltage range, Zener diode Z2 will continue to maintain the regulated state. Then, there will be current flowing through resistor R3 and resistor R4 in the Zener diode Z2 in the regulated state, and a voltage division is formed through them. Then, transistor Q1 conducts and shorts the internal diode of optocoupler OC1, making the optocoupler OC1 non-conductive, thus preventing the optocoupler OC1 from generating any output signal. Since the optocoupler OC1 is non-conductive, the WK_ID signal is pulled low to a low level by resistor R5. At this time, the WK_ID signal indicates that the charger voltage has exceeded the safe range, and there is no activation action on the microcontroller MCU, and the microcontroller will not perform any judgment or action on the charger voltage. The microcontroller does not need to execute the judgment on the action of the charger voltage. By pulling low the WK_ID signal when the charger voltage exceeds the appropriate range, it is ensured that the microcontroller MCU does not perform an invalid judgment on the charger voltage, thus avoiding incorrect operations or unnecessary interventions during the charging process.

[0035] Preferably, the recognition method further includes: When a charger is connected, the charger voltage is lower than the regulated voltages of Zener diode Z1 and Zener diode Z2. Then both Zener diode Z1 and Zener diode Z2 are not in the regulated state, and the charger voltage is lower than the appropriate voltage range. Since the charger voltage is lower than the appropriate voltage range, Zener diode Z1 and Z2 cannot play their voltage regulation role, and the entire system is not in the regulated state. Under such voltage conditions, the optocoupler OC1 is non-conductive. Among them, the conduction or non-conduction of the optocoupler usually depends on the operating voltage of the circuit or other control signals. Due to insufficient voltage, there is not enough current for the internal photodiode of the optocoupler OC1 to conduct, resulting in its output remaining in the non-conductive state. Since the optocoupler OC1 is non-conductive, at this time, WK_ID is pulled low to a low level by resistor R5. The low-level WK_ID signal indicates that the charger voltage is in an inappropriate range and cannot meet the voltage requirements of the system. After the microcontroller MCU detects that the WK_ID signal is at a low level, it will not be activated. Since no activation signal is received, the microcontroller does not need to execute the judgment on the action of the charger voltage.

[0036] Preferably, the recognition method further includes: When no charger is connected, both Zener diode Z1 and Zener diode Z2 are not in the regulated state, the optocoupler OC1 is non-conductive. At this time, WK_ID is pulled low to a low level by resistor R5, and there is no activation action on the microcontroller MCU, and the microcontroller does not need to execute the judgment on the action of the charger voltage.

[0037] Embodiment 3: The present application also provides a charger, and the charger uses an isolation charger voltage range identification circuit as described in Embodiment 1 to identify the isolation charger voltage range.

[0038] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application thereto. Those of ordinary skill in the art can make various changes and modifications therein without departing from the scope and spirit of the present application. All such changes and modifications are intended to be included within the scope of the present application as claimed in the appended claims.

[0039] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present application.

[0040] In several embodiments provided by the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed.

[0041] It should be noted that in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover a non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the presence of additional identical elements in the process, method, article or device including the element.

[0042] Although the description of the present application is made in conjunction with the above specific embodiments, it is obvious that those skilled in the art can make many substitutions, modifications and changes based on the above content. Therefore, all such substitutions, improvements and changes are included within the spirit and scope of the appended claims.

Claims

1. An isolation charger voltage range identification circuit, characterized in that The circuit includes: a voltage stabilizing diode Z1, a voltage stabilizing diode Z2, a triode Q1, an optocoupler OC1, a microcontroller MCU, and a MOS transistor Q2; One end of the voltage stabilizing diode Z1 is connected to the positive electrode of the battery cell, and the other end is connected to the collector of the triode Q1; One end of the voltage stabilizing diode Z2 is connected to the positive electrode of the battery cell, and the other end is connected to the base of the triode Q1; The collector of the triode Q1 is connected to the optocoupler OC1, and the other end of the optocoupler OC1 is connected to the microcontroller MCU; The microcontroller MCU is connected to the negative electrode of the battery cell through the MOS transistor Q2; Among them, the voltage stabilizing diode Z1 is used to set the lower limit voltage of the charger, the voltage stabilizing diode Z2 is used to set the upper limit voltage of the charger, and the voltage stabilizing value of the voltage stabilizing diode Z2 needs to be higher than that of the voltage stabilizing diode Z1.

2. The isolation charger voltage range identification circuit according to claim 1, characterized in that A resistor R2 is also connected between the voltage stabilizing diode Z1 and the collector of the triode Q1.

3. The isolation charger voltage range identification circuit according to claim 2, characterized in that A resistor R3 is also connected between the voltage stabilizing diode Z2 and the base of the triode Q1; The base of the triode Q1 is also connected to a resistor R4, and the other end of the resistor R4 is connected to the emitter of the triode Q1; the emitter of the triode Q1 is also connected to the positive electrode of the diode D1; the positive electrode of the diode D1 is also connected to the optocoupler OC1; The negative electrode of the diode D1 is connected to the source of the MOS transistor Q2.

4. The isolation charger voltage range identification circuit according to claim 3, characterized in that The optocoupler OC1 is connected to the microcontroller MCU through a resistor R1 and a resistor R5 respectively; The other end of the resistor R5 is also grounded; The microcontroller MCU is used to detect the WK_ID signal of the optocoupler OC1.

5. The isolation charger voltage range identification circuit according to claim 4, characterized in that The source of the MOS transistor Q2 is also used to be connected to the negative terminal of the charger; The gate of the MOS transistor Q2 is connected to the microcontroller MCU; The drain of the MOS transistor Q2 is connected to the negative electrode of the battery cell.

6. A recognition method using an isolation charger voltage range recognition circuit as claimed in claims 1-5, characterized in that, The identification method includes: When a charger is connected, if the charger voltage is higher than the voltage stabilizing value of the voltage stabilizing diode Z1 and lower than the voltage stabilizing value of the voltage stabilizing diode Z2, then the voltage stabilizing diode Z1 is in a voltage stabilizing state, the voltage stabilizing diode Z2 is not in a voltage stabilizing state, the charger voltage is within a suitable range, the optocoupler OC1 conducts, and at this time WK_ID is pulled high to a high level by the resistor R1, which has an activation action on the microcontroller MCU; the activated microcontroller MCU detects the WK_ID signal; If the WK_ID signal continuously maintains a high level state, it is determined that the charger is connected and the charger voltage is within a suitable range, then the microcontroller MCU outputs a signal to drive the MOS transistor Q2 to allow the charger to charge the battery cell group; During charging, the voltage of the battery cell group will rise slowly. If during the charging process, the voltage of the battery cell group is higher than the regulated voltage value of the voltage regulator diode Z2, there will be current flowing through resistor R3 and resistor R4 in the voltage regulator diode Z2 in the regulated state, then the triode Q1 conducts and shorts the internal diode of the optocoupler OC1, making the optocoupler OC1 non-conductive. At this time, WK_ID is pulled low to a low level by resistor R5. The microcontroller MCU judges according to the WK_ID signal that the charger voltage is not within the appropriate range at this time, stops outputting a signal to drive the MOS transistor Q2, and prohibits the charger from charging the battery cell group.

7. The recognition method according to claim 6, wherein It also includes: When a charger is connected, the charger voltage is higher than the regulated voltage values of the voltage regulator diode Z1 and the voltage regulator diode Z2, then both the voltage regulator diode Z1 and the voltage regulator diode Z2 are in the regulated state. If the charger voltage exceeds the appropriate voltage range, there will be current flowing through resistor R3 and resistor R4 in the voltage regulator diode Z2 in the regulated state, then the triode Q1 conducts and shorts the internal diode of the optocoupler OC1, making the optocoupler OC1 non-conductive. At this time, WK_ID is pulled low to a low level by resistor R5, and there is no activation action on the microcontroller MCU. The microcontroller does not need to execute the action of judging the charger voltage.

8. The recognition method according to claim 7, wherein It also includes: When a charger is connected, the charger voltage is lower than the regulated voltage values of the voltage regulator diode Z1 and the voltage regulator diode Z2, then neither the voltage regulator diode Z1 nor the voltage regulator diode Z2 is in the regulated state. The charger voltage is lower than the appropriate voltage range, and the optocoupler OC1 is non-conductive. At this time, WK_ID is pulled low to a low level by resistor R5, and there is no activation action on the microcontroller MCU. The microcontroller does not need to execute the action of judging the charger voltage.

9. The recognition method according to claim 8, wherein It also includes: When no charger is connected, neither the voltage regulator diode Z1 nor the voltage regulator diode Z2 is in the regulated state, and the optocoupler OC1 is non-conductive. At this time, WK_ID is pulled low to a low level by resistor R5, and there is no activation action on the microcontroller MCU. The microcontroller does not need to execute the action of judging the charger voltage.

10. A charger, characterized in that, The charger uses an isolated charger voltage range identification circuit as described in claims 1-5 to identify the isolated charger voltage range.

Images