Low-power power supply module, lithium battery protection board, power supply circuit and generation method

Abstract

The present invention provides a low-power power supply module, a lithium battery protection board, a power supply circuit, and a power generation method, comprising: a voltage divider unit, a PMOS transistor, a first resistor, a second resistor, a voltage stabilizing diode, and an NPN transistor; the voltage divider unit receives an input voltage and divides the input voltage; the drain of the PMOS transistor is connected to the output end of the voltage divider unit, the gate is grounded, and the source is connected to the base and collector of the NPN transistor via the first and second resistors, respectively; the cathode of the voltage stabilizing diode is connected to the base of the NPN transistor, and the anode is grounded; the emitter of the NPN transistor outputs a preset voltage. The present invention improves the power supply portion of the lithium battery protection board, thereby reducing the static power consumption of the power supply portion of the lithium battery protection board, reducing energy waste, and increasing the battery life.

Description

Technical Field

[0001] The present invention relates to the field of power electronics, and in particular to a low-power power supply module, a lithium battery protection board, a power supply circuit and a generation method thereof. Background Art

[0002] With the advancement of science and technology, the demand for mobile devices is increasing. Since most mobile devices are currently equipped with lithium batteries, the demand for lithium batteries is also increasing. In today's society, lithium-ion batteries have become an indispensable part of our lives. The average person owns several lithium-ion batteries. Whether it's a mobile phone, a laptop, or a digital camera, lithium-ion batteries are indispensable.

[0003] Every lithium-ion battery comes with a protection board to protect it. In our daily lives, even when our mobile devices are in standby mode, the battery often displays a low charge status. This is because the lithium-ion battery's protection board generates significant static power consumption, causing the battery to consume a lot of energy. Batteries have a lifespan; after a certain number of charge and discharge cycles, the battery becomes scrapped. This significant static power loss also shortens the battery's lifespan, indirectly wasting a lot of a country's energy resources and causing significant environmental pollution.

[0004] Therefore, how to reduce the static power consumption of the power supply part of the lithium battery protection board, reduce the waste of electric energy, and increase the service life of the battery has become one of the problems that need to be solved urgently by those skilled in the art. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a low-power power supply module, a lithium battery protection board, a power supply circuit and a generation method, which are used to solve the problems of high static power consumption, waste of electricity, short battery life and the like in the prior art.

[0006] To achieve the above-mentioned and other related purposes, the present invention provides a low-power supply module, which includes at least:

[0007] A voltage dividing unit, a PMOS tube, a first resistor, a second resistor, a voltage stabilizing diode and an NPN transistor;

[0008] The voltage dividing unit receives an input voltage and divides the input voltage;

[0009] The drain of the PMOS tube is connected to the output end of the voltage divider unit, the gate is grounded, and the source is connected to the base and collector of the NPN transistor via the first resistor and the second resistor respectively;

[0010] The cathode of the voltage stabilizing diode is connected to the base of the NPN transistor, and the anode is grounded;

[0011] The emitter of the NPN transistor outputs a preset voltage.

[0012] Optionally, the low-power power supply module further includes a first diode, an anode of the first diode is connected to the emitter of the NPN transistor, and a cathode of the first diode outputs the preset voltage.

[0013] To achieve the above-mentioned and other related purposes, the present invention further provides a lithium battery protection power supply circuit, which at least includes:

[0014] A first power supply module, a second power supply module and a power supply module, wherein the first power supply module adopts the above-mentioned low-power power supply module;

[0015] The first power supply module takes the battery voltage as input voltage and converts the battery voltage into a preset voltage;

[0016] The second power supply module receives the battery voltage and converts the battery voltage into a preset voltage;

[0017] The power supply module is connected to the output ends of the first power supply module and the second power supply module, and generates a power supply voltage based on the preset voltage;

[0018] The power consumption of the first power supply module is less than the power consumption of the second power supply module.

[0019] Optionally, the lithium battery protection power supply circuit further includes a second diode, an anode of the second diode receives the battery voltage, and a cathode is connected to the input ends of the first power supply module and the second power supply module.

[0020] Optionally, the second power supply module includes a control switch unit, a DC conversion unit and a feedback unit;

[0021] The control switch unit is connected between the battery voltage and the power supply input terminal of the DC conversion unit, and the control terminal receives a control signal for turning on or off the power supply path of the DC conversion unit;

[0022] The feedback unit is connected to the feedback terminal of the DC conversion unit, and is used to feed back the preset voltage to the DC conversion unit;

[0023] The DC conversion unit generates the preset voltage based on the output signals of the control switch unit and the feedback unit.

[0024] More optionally, the control switch unit includes a PNP transistor, a third resistor and a fourth resistor; the emitter of the PNP transistor is connected to the battery voltage, the collector is connected to the power supply input end of the DC conversion unit, and the base receives the control signal via the third resistor; the fourth resistor is connected between the emitter and the base of the PNP transistor.

[0025] More optionally, the feedback unit includes a fifth resistor, a sixth resistor and a first capacitor; one end of the fifth resistor is connected to the preset voltage, and the other end is grounded via the sixth resistor, and the connection node between the fifth resistor and the sixth resistor is connected to the feedback end of the DC conversion unit; the upper plate of the first capacitor is connected to the preset voltage, and the lower plate is connected to the feedback end of the DC conversion unit.

[0026] More optionally, the second power supply module also includes a filtering unit, the filtering unit includes a second capacitor and an inductor, the first end of the inductor is connected to the output end of the DC conversion unit, and the second end outputs the preset voltage; the upper plate of the second capacitor is connected to the second end of the inductor, and the lower plate is grounded.

[0027] More optionally, the second power supply module further includes a voltage stabilizing unit, and the voltage stabilizing unit is connected to the output end of the DC conversion unit.

[0028] To achieve the above-mentioned and other related purposes, the present invention further provides a lithium battery protection board, which comprises at least:

[0029] Microcontrol unit, protection switch and the above-mentioned lithium battery protection power supply circuit;

[0030] The lithium battery protection power supply circuit generates a power supply voltage based on the battery voltage, and supplies power to the micro control unit based on the power supply voltage;

[0031] The micro control unit receives the detection voltage of the lithium battery and generates corresponding control signals and protection signals;

[0032] The protection switch is connected in series with the lithium battery and switches on or off the path where the lithium battery is located based on the protection signal.

[0033] To achieve the above-mentioned and other related purposes, the present invention further provides a method for generating a lithium battery protection power supply. Based on the above-mentioned lithium battery protection board, the method for generating a lithium battery protection power supply at least comprises:

[0034] When the lithium battery protection board is working normally, the first power supply module and the second power supply module work simultaneously to generate a preset voltage, and generate the power supply voltage of the lithium battery protection board based on the preset voltage;

[0035] When the lithium battery protection board is in standby mode, the second power supply module stops working, the first power supply module generates the preset voltage, and generates the power supply voltage of the lithium battery protection board based on the preset voltage.

[0036] As described above, the low-power power supply module, lithium battery protection board, power supply circuit and generation method of the present invention have the following beneficial effects:

[0037] 1. In standby mode, the static power consumption of the lithium battery protection board of the present invention is significantly reduced.

[0038] 2. During normal operation, the microcontroller unit in the lithium battery protection board of the present invention has two power supply parts. When one of the power supply parts fails, the other power supply part can be used. Once a fault occurs, the lithium battery protection board can protect the battery in time, thereby improving the safety of the lithium battery protection board.

[0039] 3. The present invention increases the service life of the battery, reduces the waste of resources, and is beneficial to environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Shown is a structural schematic diagram of the low-power power supply module of the present invention.

[0041] Figure 2 Shown is a structural schematic diagram of the lithium battery protection power supply circuit of the present invention.

[0042] Figure 3 Shown is a schematic structural diagram of the lithium battery protection board of the present invention.

[0043] Component number description

[0044] 1 Lithium battery protection power circuit

[0045] 11 Low power supply module / first power supply module

[0046] 111 voltage divider unit

[0047] 12 Second power supply module

[0048] 121 Control switch unit

[0049] 122 DC conversion unit

[0050] 123 Feedback Unit

[0051] 124 filter units

[0052] 13 Power Module

[0053] 131 Power Chip

[0054] 2 Microcontroller unit

[0055] 3 Protection switch

[0056] Steps S1-S2 DETAILED DESCRIPTION

[0057] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0058] See also Figures 1 to 3 It should be noted that the diagrams provided in this embodiment are merely schematic illustrations of the basic concept of the present invention. Therefore, the diagrams only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0059] Example 1

[0060] like Figure 1 As shown, this embodiment provides a low-power power supply module 11, and the low-power power supply module 11 includes:

[0061] The voltage dividing unit 111 , the PMOS transistor Q1 , the first resistor R1 , the second resistor R2 , the voltage stabilizing diode Dz and the NPN transistor Q2 .

[0062] like Figure 1 As shown, the voltage dividing unit 111 receives an input voltage Vin and divides the input voltage Vin.

[0063] Specifically, in this embodiment, the voltage divider unit 111 is implemented using voltage divider resistors. As an example, the voltage divider unit 111 includes a seventh resistor R7 and an eighth resistor R8; one end of the seventh resistor R7 receives the input voltage Vin, and the other end is connected to the eighth resistor R8; the other end of the eighth resistor R8 is grounded; and the node connecting the seventh resistor R7 and the eighth resistor R8 outputs the divided voltage. In actual use, the voltage divider unit 111 can be implemented using any circuit structure that can achieve a voltage divider function, and is not limited to this embodiment.

[0064] like Figure 1 As shown, the drain of the PMOS transistor Q1 is connected to the output end of the voltage divider unit 111 , the gate is grounded, and the source is connected to the base and collector of the NPN transistor Q2 via the first resistor R1 and the second resistor R2 , respectively.

[0065] Specifically, the drain of the PMOS transistor Q1 is connected to the connection node of the seventh resistor R7 and the eighth resistor R8, the gate is grounded, the source is connected to the base of the NPN transistor Q2 through the first resistor R1, and the source is also connected to the collector of the NPN transistor Q2 through the second resistor R2. The output voltage of the voltage divider unit 111 makes the gate-source voltage V GS When the turn-on voltage is reached, the PMOS tube Q1 is turned on.

[0066] like Figure 1 As shown, the cathode of the voltage stabilizing diode Dz is connected to the base of the NPN transistor Q2, and the anode is grounded.

[0067] Specifically, the voltage stabilizing diode Dz clamps the base voltage of the NPN transistor Q2. As an example, the voltage across the voltage stabilizing diode Dz is 6.8V. In actual use, it can be set according to actual needs and is not limited to this embodiment.

[0068] like Figure 1 As shown, the emitter of the NPN transistor Q2 outputs a preset voltage.

[0069] Specifically, as an example, the voltage value of the preset voltage is 5V. In actual use, it can be set according to actual needs and is not limited to this embodiment.

[0070] like Figure 1 As shown, as another implementation of the present invention, the low-power power supply module 11 also includes a first diode D1, the anode of the first diode D1 is connected to the emitter of the NPN transistor Q2, and the cathode outputs the preset voltage. The voltage at the base of the NPN transistor Q2 is reduced to 5V (the voltage value of the preset voltage) via the diode voltage drop of the NPN transistor Q2 and the first diode D1. The first diode D1 is also used to prevent the output current of the low-power power supply module 11 from flowing back, protecting the low-power power supply module 11; when there is no risk of backflow, the first diode D1 can be omitted.

[0071] It should be noted that the PMOS transistor Q1 of the present invention is a voltage drop device, which generates very small loss and can greatly reduce power consumption.

[0072] Example 2

[0073] like Figure 2 As shown, this embodiment provides a lithium battery protection power supply circuit 1, and the lithium battery protection power supply circuit 1 includes:

[0074] A first power supply module 11 , a second power supply module 12 and a power supply module 13 .

[0075] like Figure 2 As shown, the first power supply module 11 takes the battery voltage as the input voltage Vin and converts the battery voltage into a preset voltage.

[0076] Specifically, the circuit structure and principle of the first power supply module 11 are described in Example 1 and are not detailed here. In this embodiment, the first power supply module 11 is connected to the positive electrode B+ of the battery; in actual use, the first power supply module 11 can be connected to any node of the battery pack that can provide sufficient power to the first power supply module 11.

[0077] like Figure 2 As shown, the second power supply module 12 receives the battery voltage and converts the battery voltage into a preset voltage.

[0078] Specifically, in this embodiment, the second power supply module 12 is connected to the positive electrode B+ of the battery; in actual use, the second power supply module 12 can be connected to any node of the battery pack as long as sufficient power is provided to the second power supply module 12 .

[0079] Specifically, in this embodiment, the second power supply module 12 includes a control switch unit 121, a DC conversion unit 122, and a feedback unit 123. The control switch unit 121 is connected between the battery voltage and the power input terminal (VIN) of the DC conversion unit 122. The control terminal receives a control signal CTL for turning the power supply path of the DC conversion unit 122 on or off. As an example, the control switch unit 121 includes a PNP transistor Q3, a third resistor R3, and a fourth resistor R4. The emitter of the PNP transistor Q3 is connected to the battery voltage, the collector is connected to the power input terminal of the DC conversion unit 122 (providing the bus voltage VBUS), and the base receives the control signal CTL via the third resistor R3. The fourth resistor R4 is connected between the emitter and base of the PNP transistor Q3. When the control signal CTL is high, the PNP transistor Q3 is turned off, and when the control signal CTL is low, the PNP transistor Q3 is turned on. The feedback unit 123 is connected to the feedback terminal (FB) of the DC conversion unit 122 and is used to feed back the preset voltage to the DC conversion unit 122. As an example, the feedback unit 123 includes a fifth resistor R5, a sixth resistor R6, and a first capacitor C1; one end of the fifth resistor R5 is connected to the preset voltage, and the other end is grounded via the sixth resistor R6; the connection node between the fifth resistor R5 and the sixth resistor R6 is connected to the feedback terminal of the DC conversion unit 122; the upper plate of the first capacitor C1 is connected to the preset voltage, and the lower plate is connected to the feedback terminal of the DC conversion unit 122. The DC conversion unit 122 generates the preset voltage based on the output signals of the control switch unit 121 and the feedback unit 123; as an example, the DC conversion unit 122 is a DCDC chip, whose enable terminal (EN) receives the enable signal EN and the ground terminal is grounded; any circuit structure that can achieve DC-DC conversion is applicable to the DC conversion unit 122, and is not limited to this embodiment.

[0080] As another implementation of the present invention, the second power supply module 12 further includes a filtering unit 124. In this embodiment, the filtering unit 124 includes a second capacitor and an inductor L. The first end of the inductor L is connected to the output end (SW) of the DC conversion unit 122, and the second end outputs the preset voltage; the upper plate of the second capacitor is connected to the second end of the inductor L, and the lower plate is grounded. As an example, the second capacitor includes two capacitors C21 and C22 connected in parallel. In actual use, any circuit structure that can realize the filtering function is applicable to the present invention, and they are not described here one by one.

[0081] As another implementation of the present invention, the second power supply module 12 further includes a voltage stabilizing unit connected to the output end of the DC conversion unit 122. As an example, the voltage stabilizing unit is implemented using a third diode D3, the cathode of the third diode D3 being connected to the output end of the DC conversion unit 122 and the anode being grounded.

[0082] It should be noted that the power consumption of the first power supply module 11 is less than that of the second power supply module 12. Any circuit structure that can realize DC conversion and obtain the preset voltage (as an example, the preset voltage is set to 5V) is suitable for the second power supply module 12 of the present invention, and will not be described one by one here.

[0083] like Figure 2 As shown, the power supply module 13 is connected to the output ends of the first power supply module 11 and the second power supply module 12, and generates a power supply voltage based on the preset voltage.

[0084] Specifically, in this embodiment, the power module 13 includes a power chip 131 and a third capacitor C3. The power chip 131 receives the preset voltage and generates a power supply voltage based on the preset voltage. As an example, the power supply voltage is 3.3V. In actual use, the value of the power supply voltage can be set as needed, and is not limited to this embodiment. The upper plate of the third capacitor C3 is connected to the output terminal of the power chip 131, and the lower plate is grounded. In actual use, any circuit structure that can generate the required power supply voltage is applicable to the present invention, and is not limited to this embodiment.

[0085] like Figure 2 As shown, as another implementation of the present invention, the lithium battery protection power supply circuit 1 further includes a second diode D2. The anode of the second diode D2 receives the battery voltage, and the cathode is connected to the input terminals of the first power supply module 11 and the second power supply module 12; it is used to prevent backflow.

[0086] This embodiment provides two power supply paths for the power module 13 , and can select different power supply paths for power supply based on different working states, thereby achieving low power consumption and high safety.

[0087] Example 3

[0088] like Figure 3 As shown, this embodiment provides a lithium battery protection board, which includes:

[0089] Micro control unit 2, protection switch 3 and lithium battery protection power supply circuit 1.

[0090] like Figure 3As shown, the lithium battery protection power supply circuit 1 generates a power supply voltage based on the battery voltage, and supplies power to the micro control unit 2 based on the power supply voltage.

[0091] Specifically, the structure and working principle of the lithium battery protection power supply circuit 1 refer to the second embodiment, which will not be described in detail here.

[0092] like Figure 3 As shown, the micro control unit 2 receives the detection voltage of the lithium battery (not shown in the figure) and generates corresponding control signals and protection signals.

[0093] Specifically, in this embodiment, the microcontroller unit 2 (MCU) obtains power from the lithium battery protection power circuit 1 and generates corresponding control signals and protection signals according to the working state. The specific principles are not described here one by one.

[0094] like Figure 3 As shown, the protection switch 3 is connected in series with the lithium battery, and switches on or off the path where the lithium battery is located based on the protection signal.

[0095] Example 4

[0096] Figures 1 to 3 As shown, this embodiment provides a method for generating a lithium battery protection power supply. In this embodiment, the method for generating a lithium battery protection power supply is implemented based on the lithium battery protection board of the third embodiment. The method for generating a lithium battery protection power supply includes:

[0097] S1) When the lithium battery protection board is working normally, the first power supply module and the second power supply module work simultaneously to generate a preset voltage, and generate the power supply voltage of the lithium battery protection board based on the preset voltage.

[0098] Specifically, in this embodiment, when the lithium battery protection board is operating normally, the microcontroller unit 2 outputs a low-level control signal, and both the first power supply module 11 and the second power supply module 12 supply power. At this point, there are two power supply paths for the power supply module 13. If one path fails, the other path can provide power. This protects the battery in a timely manner in the event of a fault, improving safety.

[0099] More specifically, the battery voltage is input into the first power supply module 11 via the second diode D2, and is divided by the voltage divider unit 111 so that the PMOS transistor Q1 obtains a turn-on voltage. The PMOS transistor Q1 is turned on, and the voltage stabilizing diode Dz provides a 6.8V clamping voltage for the base of the NPN transistor Q2. The 6.8V clamping voltage is stepped down to a 5V power supply voltage through the voltage drop of the NPN transistor Q2 and the first diode D1.

[0100] More specifically, the battery voltage is input into the second power supply module 12 via the second diode D2, and the collector and emitter of the PNP transistor Q3 are turned on via the third resistor and the fourth resistor R4. The battery voltage then powers the DC conversion unit 122, which generates a 5V voltage through feedback adjustment.

[0101] S2) When the lithium battery protection board is in standby mode, the first power supply module stops working, and the second power supply module generates the preset voltage and generates the power supply voltage of the lithium battery protection board based on the preset voltage.

[0102] Specifically, in this embodiment, when the lithium battery protection board is in standby mode, the microcontroller unit 2 outputs a high-level control signal, the first power supply module 11 supplies power, and the second power supply module 12 stops working. At this time, only the first power supply module 11 supplies power. Since the first power supply module 11 has relatively low power consumption, it can effectively reduce static power consumption, extend battery life, reduce resource waste, and promote environmental protection. The working principle of the first power supply module 11 is not detailed here.

[0103] It should be noted that the levels of the control signals corresponding to different working states can be set as needed and are not limited to this embodiment. In this embodiment, the first power supply module 11 supports the power supply requirements in standby mode, and the second power supply module 12 supports the power supply requirements in normal operation.

[0104] In summary, the present invention provides a low-power power supply module, a lithium battery protection board, a power supply circuit and a generation method, comprising: a voltage divider unit, a PMOS tube, a first resistor, a second resistor, a voltage stabilizing diode and an NPN transistor; the voltage divider unit receives an input voltage and divides the input voltage; the drain of the PMOS tube is connected to the output end of the voltage divider unit, the gate is grounded, and the source is connected to the base and collector of the NPN transistor via the first resistor and the second resistor respectively; the cathode of the voltage stabilizing diode is connected to the base of the NPN transistor, and the anode is grounded; the emitter of the NPN transistor outputs a preset voltage. The low-power power supply module, lithium battery protection board, power supply circuit and generation method of the present invention significantly reduce the static power consumption of the lithium battery protection board in standby mode; during normal operation, the microcontroller unit in the lithium battery protection board has two power supply parts. When one of the parts fails, the other part can still be used for power supply; once a fault occurs, the lithium battery protection board can protect the battery in time, thereby improving the safety of the lithium battery protection board; the present invention increases the service life of the battery, reduces the waste of resources, and is beneficial to environmental protection. Therefore, the present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0105] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A lithium battery protection power supply circuit, characterized in that: The lithium battery protection power supply circuit at least includes: A first power supply module, a second power supply module and a power supply module; The first power supply module converts the battery voltage into a preset voltage; wherein the first power supply module includes a voltage divider unit, a PMOS transistor, a first resistor, a second resistor, a voltage stabilizing diode, an NPN transistor, and a first diode; the voltage divider unit receives the battery voltage and divides the battery voltage; the drain of the PMOS transistor is connected to the output end of the voltage divider unit, the gate is grounded, and the source is connected to the base and collector of the NPN transistor via the first resistor and the second resistor respectively; the cathode of the voltage stabilizing diode is connected to the base of the NPN transistor, and the anode is grounded; the anode of the first diode is connected to the emitter of the NPN transistor, and the cathode serves as the output end; The second power supply module receives the battery voltage and converts the battery voltage into the preset voltage; The power supply module is connected to the output ends of the first power supply module and the second power supply module, and generates a power supply voltage based on a preset voltage output by the first power supply module and / or the second power supply module; The power consumption of the first power supply module is less than the power consumption of the second power supply module.

2. The lithium battery protection power supply circuit according to claim 1, characterized in that: The lithium battery protection power supply circuit further includes a second diode, an anode of the second diode receives the battery voltage, and a cathode of the second diode is connected to the input ends of the first power supply module and the second power supply module.

3. The lithium battery protection power supply circuit according to claim 1, wherein: The second power supply module includes a control switch unit, a DC conversion unit and a feedback unit; The control switch unit is connected between the battery voltage and the power supply input terminal of the DC conversion unit, and the control terminal receives a control signal for turning on or off the power supply path of the DC conversion unit; The feedback unit is connected to the feedback terminal of the DC conversion unit, and is used to feed back the preset voltage output by the second power supply module to the DC conversion unit; The DC conversion unit generates the preset voltage based on the output signals of the control switch unit and the feedback unit.

4. The lithium battery protection power supply circuit according to claim 3, characterized in that: The control switch unit includes a PNP transistor, a third resistor and a fourth resistor; the emitter of the PNP transistor is connected to the battery voltage, the collector is connected to the power supply input end of the DC conversion unit, and the base receives the control signal via the third resistor; the fourth resistor is connected between the emitter and base of the PNP transistor.

5. The lithium battery protection power supply circuit according to claim 3, characterized in that: The feedback unit includes a fifth resistor, a sixth resistor and a first capacitor; one end of the fifth resistor is connected to the output end of the second power supply module, and the other end is grounded via the sixth resistor, and the connection node between the fifth resistor and the sixth resistor is connected to the feedback end of the DC conversion unit; the upper plate of the first capacitor is connected to the output end of the second power supply module, and the lower plate is connected to the feedback end of the DC conversion unit.

6. The lithium battery protection power supply circuit according to any one of claims 3 to 5, characterized in that: The second power supply module also includes a filtering unit, which includes a second capacitor and an inductor. The first end of the inductor is connected to the output end of the DC conversion unit, and the second end is connected to the output end of the second power supply module; the upper plate of the second capacitor is connected to the second end of the inductor, and the lower plate is grounded.

7. The lithium battery protection power supply circuit according to any one of claims 3 to 5, characterized in that: The second power supply module further includes a voltage stabilizing unit connected to the output end of the DC conversion unit.

8. A lithium battery protection board, characterized in that: The lithium battery protection board at least includes: A microcontroller unit, a protection switch, and a lithium battery protection power supply circuit according to any one of claims 1 to 7; The lithium battery protection power supply circuit generates a power supply voltage based on the battery voltage, and supplies power to the micro control unit based on the power supply voltage; The micro control unit receives the detection voltage of the lithium battery and generates corresponding control signals and protection signals; The protection switch is connected in series with the lithium battery and switches on or off the path where the lithium battery is located based on the protection signal.

9. A method for generating a lithium battery protection power supply, based on the lithium battery protection board according to claim 8, characterized in that: The method for generating a lithium battery protection power supply at least includes: When the lithium battery protection board is working normally, the first power supply module and the second power supply module work simultaneously to generate a preset voltage, and generate the power supply voltage of the lithium battery protection board based on the preset voltage; When the lithium battery protection board is in standby mode, the second power supply module stops working, the first power supply module generates the preset voltage, and generates the power supply voltage of the lithium battery protection board based on the preset voltage.

Images