Battery reverse connection prevention circuit in Boost, emergency device and lighting system

Abstract

The utility model provides a battery anti-reverse-connection circuit in Boost, an emergency device and a lighting system. In the battery anti-reverse-connection circuit, a battery voltage end of a reverse-connection cut-off driving module is respectively connected with a control module, a charging module and an inductor and is used for being connected with a positive electrode of a battery interface; the grounding voltage end of the charging module is connected with the drain electrode of the second NMOS tube and used for being connected with the negative electrode of the battery interface and the negative electrode of the lighting LED, the charging voltage end of the charging module is connected with the charging module and used for being connected with the charging interface, and the output end of the charging module is connected with the grid electrode of the second NMOS tube; the control module is respectively connected with the drain electrode and the grid electrode of the first NMOS tube and the source electrode of the second NMOS tube; the drain electrode of the first NMOS tube and the inductor are connected to the positive electrode of the lighting LED through the first diode; wherein a charging voltage is accessed to the charging interface, and the reverse connection cut-off driving module raises the output voltage of the output end of the reverse connection cut-off driving module to the charging voltage through the charging voltage end of the reverse connection cut-off driving module, so that a battery reverse connection prevention technical scheme that normal charging can still be performed when the electric quantity of the battery is too low is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of battery application, in particular to a battery reverse connection prevention circuit in Boost, an emergency device and a lighting system. Background Art

[0002] Lithium batteries are increasingly used, and reverse polarity protection is an indispensable feature. Without this feature, lithium batteries may be turned on through the parasitic diode of the chip or device, resulting in a combustion accident. Therefore, there are the following old solutions (such as Figure 1 As shown): Use the drain terminal of an NMOS to connect to the negative electrode of the battery, and the source terminal of the NMOS to the ground of the chip. The power terminal of the chip is connected to the positive terminal of the battery and the gate terminal of the NMOS. When the battery is connected in the positive direction, the battery voltage turns on the NMOS and the chip works normally. When the battery is connected in the reverse direction, since the source of the NMOS is pulled to the negative potential of the battery by the chip parasitic diode, and the gate terminal of the NMOS is also connected to the negative potential of the battery, the NMOS is cut off and the path from the positive electrode to the negative electrode of the battery is disconnected by the NMOS. The disadvantage of this solution is that when the battery is out of power, the impedance of the NMOS will increase, causing the chip to not work properly. In addition, it cannot be used in chip solutions with integrated battery management. This solution can also be implemented with PMOS. When the above solution is applied to a scenario with a battery charging function, if the battery power is too low, the resistance of the NMOS will be very large, and the charging function will be affected.

[0003] Therefore, it is necessary to provide a battery reverse connection prevention technical solution that can still charge normally when the battery power is too low. Utility Model Content

[0004] In order to solve the above technical problems, the utility model provides a battery reverse connection prevention circuit, an emergency device and a lighting system in Boost.

[0005] The utility model provides a battery reverse connection prevention circuit in Boost, comprising a reverse connection cutoff driving module, a control module, a charging module, a first NMOS tube, a second NMOS tube, a battery interface, an inductor, and a first diode;

[0006] The battery voltage end of the reverse connection cutoff driving module is electrically connected to the battery end of the control module, the output end of the charging module, and the first end of the inductor and is used to connect the positive electrode of the battery interface, the ground voltage end is electrically connected to the drain of the second NMOS tube and is used to connect the negative electrode of the battery interface and the negative electrode of the lighting LED, the charging voltage end is electrically connected to the input end of the charging module and is used to connect the charging interface, and the output end is electrically connected to the gate of the second NMOS tube;

[0007] The ground terminal of the control module is electrically connected to the source of the first NMOS tube and the source of the second NMOS tube respectively, and the output terminal thereof is electrically connected to the gate of the first NMOS tube;

[0008] The drain of the first NMOS tube is electrically connected to the second end of the inductor and the anode of the first diode respectively;

[0009] The cathode of the first diode is used to be electrically connected to the anode of the lighting LED;

[0010] The charging interface is connected to a charging voltage, and the reverse connection cut-off driving module raises the output voltage of its output end to the charging voltage through its charging voltage end.

[0011] In a possible implementation, the reverse-connection cutoff driving module includes a second diode, a third diode, and a fourth diode;

[0012] The anode of the second diode serves as the battery voltage terminal of the reverse connection cutoff driving module, and the cathode of the second diode is electrically connected to the cathode of the third diode and the cathode of the fourth diode respectively and serves as the output terminal of the reverse connection cutoff driving module;

[0013] The anode of the third diode serves as the charging voltage terminal of the reverse-connection cut-off driving module;

[0014] The anode of the fourth diode serves as the ground voltage terminal of the reverse-connection cut-off driving module.

[0015] The utility model also provides an emergency device, comprising a battery and the battery reverse connection prevention circuit as described above;

[0016] The battery is installed in the battery interface of the battery reverse connection protection circuit.

[0017] In a possible implementation, in the above emergency device, the reverse connection cutoff driving module includes a second diode, a third diode, and a fourth diode;

[0018] The anode of the second diode serves as the battery voltage terminal of the reverse connection cutoff driving module, and the cathode of the second diode is electrically connected to the cathode of the third diode and the cathode of the fourth diode respectively and serves as the output terminal of the reverse connection cutoff driving module;

[0019] The anode of the third diode serves as the charging voltage terminal of the reverse connection cut-off driving module;

[0020] The anode of the fourth diode serves as the ground voltage terminal of the reverse-connection cut-off driving module.

[0021] The utility model also provides a lighting system, comprising a lighting LED and the above-mentioned emergency device.

[0022] In a possible implementation, in the above lighting system, the reverse connection cutoff driving module includes a second diode, a third diode, and a fourth diode;

[0023] The anode of the second diode serves as the battery voltage terminal of the reverse connection cutoff driving module, and the cathode of the second diode is electrically connected to the cathode of the third diode and the cathode of the fourth diode respectively and serves as the output terminal of the reverse connection cutoff driving module;

[0024] The anode of the third diode serves as the charging voltage terminal of the reverse connection cut-off driving module;

[0025] The anode of the fourth diode serves as the ground voltage terminal of the reverse-connection cut-off driving module.

[0026] In a possible implementation, the lighting system further includes a constant current driving module;

[0027] The constant current driving module is electrically connected to two ends of the lighting LED.

[0028] The technical solution provided by the utility model has at least the following beneficial effects:

[0029] By providing a power supply path between the charging interface and the gate of the second NMOS tube through the reverse connection cutoff driving module, the charging voltage of the charging interface can be led to the gate of the second NMOS tube, thereby raising the voltage for driving the second NMOS tube, which can not only prevent the battery from reverse connection, but also ensure normal charging of the battery when the battery power is too low. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of an existing battery reverse connection protection circuit provided by an embodiment of the utility model;

[0031] Figure 2 A circuit schematic diagram of a battery reverse connection protection circuit in a Boost provided by an embodiment of the utility model;

[0032] Figure 3 A circuit schematic diagram of a reverse connection cutoff drive module provided by an embodiment of the utility model;

[0033] In the accompanying drawings, 11, reverse cutoff drive module; 12, control module; 13, charging module; 14, first NMOS tube; 15, second NMOS tube; 16, battery interface; 17, inductor; 18, first diode; 19, lighting LED; 20, charging interface; 21, battery; 22, constant current drive module; 111, second diode; 112, third diode; 113, fourth diode. DETAILED DESCRIPTION

[0034] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments are only used to explain the present invention and do not limit the protection scope of the present invention.

[0035] Please refer to Figure 2 A battery reverse connection protection circuit in Boost includes a reverse connection cutoff driving module 11, a control module 12, a charging module 13, a first NMOS tube 14, a second NMOS tube 15, a battery interface 16, an inductor 17, and a first diode 18;

[0036] The battery voltage end of the reverse connection cutoff driving module 11 is electrically connected to the battery end of the control module 12, the output end of the charging module 13, and the first end of the inductor 17 and is used to connect the positive electrode of the battery interface 16, the ground voltage end is electrically connected to the drain of the second NMOS tube 15 and is used to connect the negative electrode of the battery interface 16 and the negative electrode of the lighting LED 19, the charging voltage end is electrically connected to the input end of the charging module 13 and is used to connect the charging interface 20, and the output end is electrically connected to the gate of the second NMOS tube 15;

[0037] The ground terminal of the control module 12 is electrically connected to the source of the first NMOS transistor 14 and the source of the second NMOS transistor 15 respectively, and the output terminal thereof is electrically connected to the gate of the first NMOS transistor 14;

[0038] The drain of the first NMOS tube 14 is electrically connected to the second end of the inductor 17 and the anode of the first diode 18 respectively;

[0039] The cathode of the first diode 18 is used to electrically connect to the anode of the lighting LED 19;

[0040] The charging interface 20 is connected to a charging voltage, and the reverse connection cut-off driving module 11 raises the output voltage of its output end to the charging voltage through its charging voltage end.

[0041] In this embodiment, the reverse connection cutoff driving module 11 is used to compare the voltages of BAT, VDD and GND, and output the high voltage among them to drive the gate of the second NMOS tube 15. The control module 12 can be implemented based on a single chip microcomputer, and adopts a conventional design to realize voltage sampling and high and low level output. The charging module 13 is used to control the charging of the battery 21, and can adopt a conventional design. The first NMOS tube 14 and the second NMOS tube 15 can both adopt conventional N-type MOS tubes, Figure 2In order to distinguish the different functions of the first NMOS tube 14 and the second NMOS tube 15, different symbols are used. The battery interface 16 adopts a conventional design and is used to connect the battery 21. The inductor 17 adopts a conventional model. The first diode 18 adopts a conventional diode. The lighting LED 19 can be composed of a plurality of conventional LEDs connected in series. The charging interface 20 can be a voltage interface or a current interface. The battery 21 can adopt a conventional rechargeable battery, such as a lithium battery.

[0042] In a specific implementation, assuming that the battery 21 is reversely connected, the battery terminal of the control module 12 and the output terminal of the charging module 13 are both at low levels, such as Figure 1 In the embodiment, the voltage of GND is high, the voltage of BAT is low, and the voltage of VDD is high (when the charging voltage exists). The control module 12 and the charging module 13 are not working, and the first NMOS tube 14 is cut off. However, due to the existence of the parasitic substrate diode, the first NMOS tube 14 cannot close the loop alone, and there is a problem of burning the device. However, the second NMOS tube 15 added in this patent is turned off by the reverse connection cut-off drive module 11. In this case, the battery 21 cannot form a loop, which can avoid the problem of burning the circuit caused by the reverse connection of the battery. Assuming that the battery 21 is connected in the forward direction, the battery end of the control module 12 and the output end of the charging module 13 both detect a high level, such as Figure 1 In the embodiment, the voltage of GND is at a low level, the voltage of BAT is at a high level, the voltage of VDD is at a high level (when a charging voltage exists), the control module 12 and the charging module 13 both work, and the first NMOS tube 14 is repeatedly turned on and off under the control of the control module 12 to charge and discharge the inductor 17. The second NMOS tube 15 always maintains a low resistance state under the action of the charging voltage on the gate. Even if the power of the battery 21 is very low, the impedance of the second NMOS tube 15 will not increase, thereby fully ensuring the normal operation of the charging module 13.

[0043] In one possible implementation, Figure 3 , the reverse connection cutoff driving module 11 includes a second diode 111, a third diode 112, and a fourth diode 113;

[0044] The anode of the second diode 111 serves as the battery voltage terminal of the reverse-connected cutoff driving module 11, and the cathode of the second diode 111 is electrically connected to the cathode of the third diode 112 and the cathode of the fourth diode 113 and serves as the output terminal of the reverse-connected cutoff driving module 11;

[0045] The anode of the third diode 112 serves as the charging voltage terminal of the reverse-connection cut-off driving module 11;

[0046] The anode of the fourth diode 113 serves as the ground voltage terminal of the reverse-connection cut-off driving module 11 .

[0047] In this embodiment, the second diode 111 , the third diode 112 , and the fourth diode 113 are all conventional diodes.

[0048] In a specific implementation, assuming that the battery 21 is reversely connected, the battery terminal of the control module 12 and the output terminal of the charging module 13 are both at low levels, such as Figure 1 In the example, the voltage of GND is high, the voltage of BAT is low, the voltage of VDD is high (when there is a charging voltage), the control module 12 and the charging module 13 are not working, the first NMOS tube 14 is turned off, the second diode 111 is turned off, the third diode 112 and the fourth diode 113 are both turned on, and the second NMOS tube 15 is turned off. The battery 21 cannot form a loop, which can avoid the problem of burning the circuit due to reverse connection of the battery. Assuming that the battery 21 is connected in the forward direction, the battery end of the control module 12 and the output end of the charging module 13 both detect a high level, such as Figure 1 In the embodiment, the voltage of GND is at a low level, the voltage of BAT is at a high level, the voltage of VDD is at a high level (when the charging voltage exists), the control module 12 and the charging module 13 are both working, the second diode 111 and the third diode 112 are both turned on, the fourth diode 113 is turned off, and the first NMOS tube 14 is repeatedly turned on and off under the control of the control module 12 to charge and discharge the inductor 17. The second NMOS tube 15 always maintains a low resistance state under the action of the charging voltage on the gate. Even if the power of the battery 21 is very low, the impedance of the second NMOS tube 15 will not increase, which can fully guarantee the normal operation of the charging module 13.

[0049] The utility model also provides an emergency device, comprising a battery 21 and the battery reverse connection prevention circuit as described above;

[0050] The battery 21 is installed in the battery interface 16 in the battery reverse connection protection circuit.

[0051] In a possible implementation, in the above emergency device, the reverse connection cutoff driving module 11 includes a second diode 111, a third diode 112, and a fourth diode 113;

[0052] The anode of the second diode 111 serves as the battery voltage terminal of the reverse-connected cutoff driving module 11, and the cathode of the second diode 111 is electrically connected to the cathode of the third diode 112 and the cathode of the fourth diode 113 and serves as the output terminal of the reverse-connected cutoff driving module 11;

[0053] The anode of the third diode 112 serves as the charging voltage terminal of the reverse-connection cut-off driving module 11;

[0054] The anode of the fourth diode 113 serves as the ground voltage terminal of the reverse-connection cut-off driving module 11 .

[0055] The utility model also provides a lighting system, comprising a lighting LED 19 and the above-mentioned emergency device.

[0056] In a possible implementation, in the above lighting system, the reverse connection cutoff driving module 11 includes a second diode 111, a third diode 112, and a fourth diode 113;

[0057] The anode of the second diode 111 serves as the battery voltage terminal of the reverse-connected cutoff driving module 11, and the cathode of the second diode 111 is electrically connected to the cathode of the third diode 112 and the cathode of the fourth diode 113 and serves as the output terminal of the reverse-connected cutoff driving module 11;

[0058] The anode of the third diode 112 serves as the charging voltage terminal of the reverse-connection cut-off driving module 11;

[0059] The anode of the fourth diode 113 serves as the ground voltage terminal of the reverse-connection cut-off driving module 11 .

[0060] In a possible implementation, the above lighting system further includes a constant current driving module 22;

[0061] The constant current driving module 22 is electrically connected to two ends of the lighting LED 19 .

[0062] In this embodiment, the constant current driving module 22 adopts a conventional module capable of providing a constant current, and can be designed based on a conventional constant current principle or directly adopt a finished product.

[0063] The above embodiments should not limit the present invention in any way, and any technical solution obtained by equivalent replacement or equivalent conversion falls within the protection scope of the present invention. For example, the diodes (the second diode 111, the third diode 112, and the fourth diode 113) can also be replaced by controlled MOSFETs to reduce the gate-to-source voltage, further enhance the cutoff characteristics of the second NMOS tube 15, and reduce the conduction risk of the second NMOS tube 15.

Claims

1. A battery reverse connection protection circuit in Boost, characterized in that: It includes a reverse connection cutoff driving module, a control module, a charging module, a first NMOS tube, a second NMOS tube, a battery interface, an inductor, and a first diode; The battery voltage end of the reverse connection cutoff driving module is electrically connected to the battery end of the control module, the output end of the charging module, and the first end of the inductor and is used to connect the positive electrode of the battery interface, the ground voltage end is electrically connected to the drain of the second NMOS tube and is used to connect the negative electrode of the battery interface and the negative electrode of the lighting LED, the charging voltage end is electrically connected to the input end of the charging module and is used to connect the charging interface, and the output end is electrically connected to the gate of the second NMOS tube; The ground terminal of the control module is electrically connected to the source of the first NMOS tube and the source of the second NMOS tube respectively, and the output terminal thereof is electrically connected to the gate of the first NMOS tube; The drain of the first NMOS tube is electrically connected to the second end of the inductor and the anode of the first diode respectively; The cathode of the first diode is used to be electrically connected to the anode of the lighting LED; The charging interface is connected to a charging voltage, and the reverse connection cut-off driving module raises the output voltage of its output end to the charging voltage through its charging voltage end.

2. The battery reverse connection protection circuit according to claim 1, characterized in that: The reverse connection cut-off driving module includes a second diode, a third diode, and a fourth diode; The anode of the second diode serves as the battery voltage terminal of the reverse connection cutoff driving module, and the cathode of the second diode is electrically connected to the cathode of the third diode and the cathode of the fourth diode respectively and serves as the output terminal of the reverse connection cutoff driving module; The anode of the third diode serves as the charging voltage terminal of the reverse-connection cut-off driving module; The anode of the fourth diode serves as the ground voltage terminal of the reverse-connection cut-off driving module.

3. An emergency device, characterized in that: comprising a battery and a battery reverse connection protection circuit as claimed in claim 1; The battery is installed in the battery interface of the battery reverse connection protection circuit.

4. The emergency device according to claim 3, characterized in that: The reverse connection cut-off driving module includes a second diode, a third diode, and a fourth diode; The anode of the second diode serves as the battery voltage terminal of the reverse connection cutoff driving module, and the cathode of the second diode is electrically connected to the cathode of the third diode and the cathode of the fourth diode respectively and serves as the output terminal of the reverse connection cutoff driving module; The anode of the third diode serves as the charging voltage terminal of the reverse-connection cut-off driving module; The anode of the fourth diode serves as the ground voltage terminal of the reverse-connection cut-off driving module.

5. A lighting system, characterized in that: Comprising an illuminating LED and an emergency device as claimed in claim 3.

6. The lighting system according to claim 5, characterized in that The reverse connection cut-off driving module includes a second diode, a third diode, and a fourth diode; The anode of the second diode serves as the battery voltage terminal of the reverse connection cutoff driving module, and the cathode of the second diode is electrically connected to the cathode of the third diode and the cathode of the fourth diode respectively and serves as the output terminal of the reverse connection cutoff driving module; The anode of the third diode serves as the charging voltage terminal of the reverse-connection cut-off driving module; The anode of the fourth diode serves as the ground voltage terminal of the reverse-connection cut-off driving module.

7. The lighting system according to claim 5, characterized in that It also includes a constant current drive module; The constant current driving module is electrically connected to two ends of the lighting LED.

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