Battery charging protection board driving circuit

Abstract

The utility model relates to a driving circuit of a battery charging protection board, which is applied to the battery charging protection board, the battery charging protection board is provided with a charging MOS tube, and the driving circuit comprises a driving control charging module, a voltage dividing module, a turn-off control module and a voltage detection driving module which are electrically connected in sequence. By utilizing the battery charging protection board driving circuit provided by the utility model, the battery can be effectively charged even under the extreme condition that the voltage of the battery is reduced to 0V, so that the normal operation of electronic equipment is ensured, and the reliability and usability of the equipment are improved.

Description

Technical Field

[0001] This utility model relates to the field of battery charging technology, and specifically to a battery charging protection board drive circuit. Background Technology

[0002] In the current field of electronic device power supply technology, integrated circuits (ICs) are key components of various electronic devices, and their normal operation typically depends on specific voltage conditions. Under existing technical solutions, ICs have a minimum operating voltage limit, which requires that the voltage of each battery string supplying them must reach a certain value. For example, in common application scenarios, when the voltage of each battery string is lower than 1.5V, the IC cannot function properly. Specifically, in circuit protection boards, battery management ICs (such as BMS chips) cannot function properly when their operating voltage is lower than 1.5V, thus preventing the charging of batteries.

[0003] In actual use, after a battery has been stored for a long time, its internal chemical energy will gradually be consumed, and self-discharge is quite common. This can cause the battery's discharge voltage to drop to 0V. This situation occurs in many electronic devices, causing inconvenience to users. Once the battery voltage drops to 0V, according to traditional drive circuit designs, it cannot be recharged to restore it, rendering the entire electronic device unusable. This not only wastes resources but may also affect the user's normal experience.

[0004] Therefore, there is an urgent need for an innovative battery charging drive circuit technology that enables effective charging of the battery even in extreme cases where the battery voltage drops to 0V, thereby ensuring the normal operation of electronic devices and improving their reliability and availability. Utility Model Content

[0005] The purpose of this invention is to provide a battery charging protection board drive circuit to solve the technical problem in the prior art that the battery cannot be charged when the battery voltage drops to 0V in extreme cases.

[0006] The technical solution provided by this utility model is as follows:

[0007] A battery charging protection board drive circuit is disclosed, applied in a battery charging protection board. The battery charging protection board is equipped with a charging MOSFET. The drive circuit includes a drive control charging module, a voltage divider module, a shutdown control module, and a voltage detection drive module, which are connected in sequence.

[0008] The drive control charging module is connected to the battery charging protection board and the battery positive terminal BATT+. The drive control charging module is used to drive and control the battery charging protection board to charge the battery.

[0009] The voltage divider module is connected to both the battery charging protection board and the battery positive terminal BATT+. The voltage divider module is used as a driving voltage divider circuit to turn on the first switching transistor Q11 in the driving control charging module.

[0010] The shutdown control module is connected to both the battery charging protection board and the voltage divider module. The shutdown control module is used to control the switching state of the first switching transistor Q11.

[0011] The voltage detection drive module is connected to the shutdown control module and the battery positive terminal BATT+. The voltage detection drive module is used to control the shutdown control module to be in the on state after detecting the preset voltage U1.

[0012] In a preferred embodiment, the drive control charging module includes a first switching transistor Q11, the collector of the first switching transistor Q11 is connected to node COH of the battery charging protection board through a resistor, the emitter of the first switching transistor Q11 is connected to node C- of the battery charging protection board, and the base of the first switching transistor Q11 is connected to the voltage divider module.

[0013] Wherein, node COH is a node connected to the charging MOS transistor switching control circuit in the battery charging protection board, which controls the switching state of the charging MOS transistor; node C- is a node connected to the negative terminal of the battery charging protection board.

[0014] In one specific embodiment, the voltage divider module includes a first voltage divider resistor R42 and a second voltage divider resistor R49, with a diode connected between the first voltage divider resistor R42 and the second voltage divider resistor R49.

[0015] In a preferred embodiment, the shutdown control module includes a second switch Q17, the collector of the second switch Q17 is connected to the voltage divider module and the base of the first switch Q11, the emitter of the second switch Q17 is connected to the node C-, the base of the second switch Q17 is connected to the node C- through a resistor, and the base of the second switch Q17 is connected to the voltage detection drive module.

[0016] In a preferred embodiment, the voltage detection drive module includes a third switch Q10. The collector of the third switch Q10 is connected to the base of the second switch Q17 through a resistor and a diode. The emitter of the third switch Q10 is connected to the positive terminal BATT+ of the battery through a Zener diode. The base of the third switch Q10 is connected to the emitter of the third switch Q10 through a resistor, and the base of the third switch Q10 is grounded through a resistor.

[0017] In a preferred embodiment, the driving circuit further includes a backup power module connected to the voltage detection driving module; the backup power module includes a current-limiting resistor and a diode connected in series, the cathode of the diode is connected to the emitter of the third switching transistor Q10, one end of the current-limiting resistor is connected to the anode of the diode, and the other end of the current-limiting resistor is connected to a voltage source.

[0018] In a preferred embodiment, the voltage of the voltage source is 3.3V, and the preset voltage U1 is 8V.

[0019] Compared with the prior art, the battery charging protection board drive circuit provided by this utility model has the following beneficial effects:

[0020] This allows for effective charging of the battery even in extreme situations where the battery voltage drops to 0V, thereby ensuring the normal operation of electronic devices and improving their reliability and availability. Attached Figure Description

[0021] Figure 1 This is a schematic block diagram of the circuit structure of a battery charging protection board driving circuit according to an embodiment of the present utility model;

[0022] Figure 2 This is a detailed circuit diagram of the start-up drive circuit described in the embodiments of this utility model.

[0023] The attached diagrams are numbered as follows: 100, Battery charging protection board; 10, Drive control charging module; 20, Voltage divider module; 30, Shutdown control module; 40, Voltage detection drive module; 50, Backup power module. Detailed Implementation

[0024] To better understand the purpose, technical solution, and technical effects of this utility model, the following description, in conjunction with the accompanying drawings and embodiments, will provide further explanation. It should also be stated that the embodiments described below are for illustrative purposes only and are not intended to limit the scope of this utility model. Example 1

[0025] like Figure 1-2 As shown, a battery charging protection board drive circuit is applied in a battery charging protection board 100. The battery charging protection board is equipped with a charging MOSFET. The drive circuit includes a drive control charging module 10, a voltage divider module 20, a shutdown control module 30, and a voltage detection drive module 40, which are connected in sequence.

[0026] The drive control charging module is connected to the battery charging protection board and the battery positive terminal BATT+. The drive control charging module is used to drive and control the battery charging protection board to charge the battery.

[0027] The voltage divider module is connected to both the battery charging protection board and the battery positive terminal BATT+. The voltage divider module is used as a driving voltage divider circuit to turn on the first switching transistor Q11 in the driving control charging module.

[0028] The shutdown control module is connected to both the battery charging protection board and the voltage divider module. The shutdown control module is used to control the switching state of the first switching transistor Q11.

[0029] The voltage detection drive module is connected to the shutdown control module and the battery positive terminal BATT+. The voltage detection drive module is used to control the shutdown control module to be in the on state after detecting the preset voltage U1.

[0030] It should be noted that the battery charging protection board 100 is a functional module circuit in the prior art, which includes a battery management IC (such as a BMS chip), a charging MOSFET, a charging MOSFET switch control circuit that controls the switching state of the charging MOSFET, a discharging MOSFET, a discharging MOSFET switch control circuit that controls the switching state of the discharging MOSFET, a battery voltage detection circuit, a protection circuit, etc. The battery charging protection board is a mature functional module circuit in the prior art, and its specific circuit structure and the functions and connections of each circuit will not be described in detail here.

[0031] In one specific implementation, as shown in the appendix Figure 2 As shown, the drive control charging module 10 includes a first switching transistor Q11. The collector of the first switching transistor Q11 is connected to node COH of the battery charging protection board through a resistor (resistor R40) and a diode (diode D9). The emitter of the first switching transistor Q11 is connected to node C- of the battery charging protection board. The base of the first switching transistor Q11 is connected to the voltage divider module. The base of the first switching transistor Q11 is also connected to the emitter of the first switching transistor Q11 through a capacitor (capacitor C58).

[0032] Wherein, node COH is a node connected to the charging MOS transistor switching control circuit in the battery charging protection board for controlling the switching state of the charging MOS transistor. When node COH is low, the charging MOS transistor is in the on state. When node COH is high, the switching state of the charging MOS transistor is controlled by the battery management IC in the battery charging protection board 100. Node C- is a node connected to the negative terminal of the battery charging protection board.

[0033] In one specific embodiment, the voltage divider module 20 includes a first voltage divider resistor R42 and a second voltage divider resistor R49, and a diode (diode D13) is connected between the first voltage divider resistor R42 and the second voltage divider resistor R49, as shown in the attached figure. Figure 2 As shown.

[0034] In a preferred embodiment, the shutdown control module 30 includes a second switch Q17. The collector of the second switch Q17 is connected to the voltage divider module 20 (specifically, the node between the second voltage divider resistor R49 and the diode D13) and the base of the first switch Q11. The emitter of the second switch Q17 is connected to the node C-. The base of the second switch Q17 is connected to the node C- through a resistor (resistor R48), and the base of the second switch Q17 is connected to the voltage detection drive module 40, as shown in the attached figure. Figure 2 As shown.

[0035] In a preferred embodiment, the voltage detection drive module 40 includes a third switch Q10. The collector of the third switch Q10 is connected to the base of the second switch Q17 through a resistor (resistor R44) and a diode (diode D). The emitter of the third switch Q10 is connected to the positive terminal BATT+ of the battery through a Zener diode (ZD9). The base of the third switch Q10 is connected to its emitter through a resistor (resistor R37), and the base of the third switch Q10 is grounded through a resistor (resistor R38). Figure 2 As shown.

[0036] In a preferred embodiment, the driving circuit further includes a backup power module 50, which is connected to the voltage detection driving module 40. The backup power module includes a current-limiting resistor R105 and a diode D20 connected in series. The cathode of the diode D20 is connected to the emitter of the third switching transistor Q10. One end of the current-limiting resistor R105 is connected to the anode of the diode D20, and the other end of the current-limiting resistor R105 is connected to a voltage source, as shown in the attached figure. Figure 2 As shown. In one specific embodiment, the voltage of the voltage source is 3.3V.

[0037] In one specific implementation, the preset voltage U1 is 8V. It should be noted that in other implementations, the specific voltage values ​​of the voltage source and the preset voltage U1 can be selected according to actual needs. For example, in other implementations, the preset voltage U1 is 9V, 10V, etc., and can be selected according to actual needs.

[0038] In this embodiment, the drive control charging module 10 is used to control the switching state of the charging MOSFET. When the switching transistor in the drive control charging module 10 is in the on state, it can control the charging MOSFET in the battery charging protection board to be turned on, thereby charging the battery. The shutdown control module 30 and the voltage detection drive module 40 can control the switching state of the switching transistor in the drive control charging module 10. When the voltage detection drive module 40 detects a preset voltage U1, the shutdown control module 30 will control the drive control charging module 10 to be in the off state, so that the charging MOSFET in the battery charging protection board is turned off. The switching state of the charging MOSFET is no longer controlled by the drive control charging module 10. At this time, the switching state of the charging MOSFET is controlled by the battery management IC in the battery charging protection board 100. The backup power module 50 is used to provide a backup power supply for the shutdown control module 30 and the voltage detection drive module 40 after the voltage detection drive module 40 detects the preset voltage U1 and the switching state of the charging MOSFET is controlled by the battery management IC in the battery charging protection board 100. This ensures that the drive control charging module 10 is in the off state, so that the drive control charging module 10 no longer controls the switching state of the charging MOSFET, ensuring that the battery management IC can work normally to control the switching state of the charging MOSFET, and ultimately enabling the battery charging protection board 100 to charge and discharge the battery normally.

[0039] The following is a brief description of the operation of the battery charging protection board drive circuit provided in this embodiment:

[0040] When the battery voltage is discharged to 0V, the solution provided by this invention will generate voltage at the positive terminal BATT+ when the battery is being charged (the voltage at the positive terminal BATT+ increases when the charger is plugged in). This voltage is divided by the first voltage divider resistor R42 and the second voltage divider resistor R49 in the voltage divider module, thereby turning on the first switching transistor Q11 and making node COH low. At this time, the charging MOSFET in the battery charging protection board is turned on, so the battery can be charged. The charging MOSFET is not controlled by the charging IC in the battery charging protection board. When the battery voltage is charged to the preset voltage U1 (8V), the Zener diode ZD9 in the voltage detection drive module conducts, thereby turning on the third switch Q10, which in turn turns on the second switch Q17. At this time, the base of the first switch Q11 is pulled low, so the first switch Q11 is in an open circuit state. The charging MOSFET is no longer controlled by the drive control charging module 10, but by the battery management IC in the battery charging protection board 100. That is, at this time, the battery management IC in the battery charging protection board 100 takes over the operation of the charging MOSFET. At the same time, when the battery voltage is charged to the preset voltage U1 (8V), the battery charging protection board 100 can work normally, providing a working voltage to the backup power module, so that the drive control charging module 10 can no longer control the charging MOSFET. That is, at this time, the drive control charging module 10 is in a failure state and can no longer control the switching state of the charging MOSFET.

[0041] The above embodiments only illustrate several implementation methods of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A battery charging protection board drive circuit, applied in a battery charging protection board, wherein the battery charging protection board is provided with a charging MOSFET, characterized in that, The drive circuit includes a drive control charging module, a voltage divider module, a shutdown control module, and a voltage detection drive module, which are connected in sequence. The drive control charging module is connected to the battery charging protection board and the battery positive terminal BATT+. The drive control charging module is used to drive and control the battery charging protection board to charge the battery. The voltage divider module is connected to both the battery charging protection board and the battery positive terminal BATT+. The voltage divider module is used as a driving voltage divider circuit to turn on the first switching transistor Q11 in the driving control charging module. The shutdown control module is connected to both the battery charging protection board and the voltage divider module. The shutdown control module is used to control the switching state of the first switching transistor Q11. The voltage detection drive module is connected to the shutdown control module and the battery positive terminal BATT+. The voltage detection drive module is used to control the shutdown control module to be in the on state after detecting the preset voltage U1.

2. The battery charging protection board driving circuit according to claim 1, characterized in that, The drive control charging module includes a first switching transistor Q11. The collector of the first switching transistor Q11 is connected to node COH of the battery charging protection board through a resistor. The emitter of the first switching transistor Q11 is connected to node C- of the battery charging protection board. The base of the first switching transistor Q11 is connected to the voltage divider module. Wherein, node COH is a node connected to the charging MOS transistor switching control circuit in the battery charging protection board, which controls the switching state of the charging MOS transistor; node C- is a node connected to the negative terminal of the battery charging protection board.

3. The battery charging protection board drive circuit according to claim 2, characterized in that, The voltage divider module includes a first voltage divider resistor R42 and a second voltage divider resistor R49, and a diode is connected between the first voltage divider resistor R42 and the second voltage divider resistor R49.

4. The battery charging protection board driving circuit according to claim 3, characterized in that, The shutdown control module includes a second switch Q17. The collector of the second switch Q17 is connected to the voltage divider module and the base of the first switch Q11. The emitter of the second switch Q17 is connected to the node C-. The base of the second switch Q17 is connected to the node C- through a resistor. The base of the second switch Q17 is also connected to the voltage detection drive module.

5. The battery charging protection board driving circuit according to claim 4, characterized in that, The voltage detection drive module includes a third switch Q10. The collector of the third switch Q10 is connected to the base of the second switch Q17 through a resistor and a diode. The emitter of the third switch Q10 is connected to the positive terminal BATT+ of the battery through a Zener diode. The base of the third switch Q10 is connected to the emitter of the third switch Q10 through a resistor, and the base of the third switch Q10 is grounded through a resistor.

6. The battery charging protection board driving circuit according to claim 5, characterized in that, The driving circuit also includes a backup power module, which is connected to the voltage detection driving module.

7. The battery charging protection board driving circuit according to claim 6, characterized in that, The backup power module includes a current-limiting resistor and a diode connected in series. The cathode of the diode is connected to the emitter of the third switching transistor Q10. One end of the current-limiting resistor is connected to the anode of the diode, and the other end of the current-limiting resistor is connected to a voltage source.

8. The battery charging protection board driving circuit according to claim 7, characterized in that, The voltage of the voltage source is 3.3V.

9. A battery charging protection board driving circuit according to claim 1, characterized in that, The preset voltage U1 is 8V.

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