Reverse protection switch circuit, power supply device and electronic equipment

Abstract

A reverse protection switch circuit, a power supply device and an electronic device. The reverse protection switch circuit includes a reverse protection switch module and a fast recovery charging module. The reverse protection switch module is used to shut down when the voltage at the second end of the reverse protection switch module is greater than the voltage at the first end of the reverse protection switch module; the fast recovery charging module is used to charge when the reverse protection switch module is turned on, and to provide a recovery voltage to the reverse protection switch module when the reverse protection switch module is restored from an off state to an on state; the recovery voltage is used to speed up the speed at which the reverse protection switch module is restored from an off state to an on state. The fast recovery charging module can speed up the speed at which the reverse protection switch module is restored from an off state to an on state, thereby avoiding the reverse protection switch circuit from having insufficient power supply capacity to the load when exiting the reverse protection state, thereby causing the load to stop working or malfunction.

Description

Technical Field

[0001] The present application belongs to the field of power supply technology, and in particular relates to a reverse protection switch circuit, a power supply device and an electronic device. Background Art

[0002] At present, in order to reduce the conduction loss of the electronic current limiting switch, the on-resistance of the traditional blocking power tube and high-side power tube is very small, generally tens of milliohms. Since the gate capacitance and on-resistance of the blocking power tube are inversely proportional, the process of the blocking power tube restoring conduction will be longer, which may easily cause the load to stop working or malfunction due to long power-off time. Summary of the invention

[0003] The purpose of the present application is to provide a reverse protection switch circuit, a power supply device and an electronic device, aiming to solve the problem of slow recovery speed existing in traditional reverse protection circuits.

[0004] A first aspect of an embodiment of the present application provides a reverse protection switch circuit, wherein the input end of the reverse protection switch circuit is used to connect a power supply, and the output end of the reverse protection switch circuit is used to connect a load, and the reverse protection switch circuit comprises: a reverse protection switch module, wherein the first end of the reverse protection switch module is connected to the input end of the reverse protection switch circuit, and the second end of the reverse protection switch module is connected to the output end of the reverse protection switch circuit; a fast recovery charging module, wherein the fast recovery charging module is connected to the reverse protection switch module; the reverse protection switch module is used to shut down when the voltage at the second end of the reverse protection switch module is greater than the first end of the reverse protection switch module; the fast recovery charging module is used to charge when the reverse protection switch module is turned on, and to provide a recovery voltage to the reverse protection switch module when the reverse protection switch module is restored from an off state to an on state; the recovery voltage is used to accelerate the speed at which the reverse protection switch module is restored from an off state to an on state.

[0005] In one embodiment, the reverse protection switch circuit includes a first working power supply, and the reverse protection switch module includes a first switch device, a second switch device and a first comparator; the first end of the first switch device is the first end of the reverse protection switch module, the second end of the first switch device is the second end of the reverse protection switch module, and the control end of the first switch device is connected to the first working power supply; the first end of the second switch device is connected to the first end of the first switch device, the second end of the second switch device is connected to the control end of the first switch device, and the control end of the second switch device is connected to the output end of the first comparator; the first input end of the first comparator is connected to the input end of the reverse protection switch circuit, and the second input end of the first comparator is connected to the output end of the reverse protection switch circuit; the first comparator is used to control the second switch device to turn on when the voltage of the second input end of the first comparator is greater than the voltage of the first input end of the first comparator.

[0006] In one embodiment, the first switch device is an N-type MOS tube, and the second switch device is a P-type MOS tube.

[0007] In one embodiment, the reverse protection switch circuit includes a second working power supply, and the fast recovery charging module includes an energy storage capacitor, a first control switch and a pulse control unit; the first end of the energy storage capacitor is connected to the input end of the reverse protection switch circuit, the second end of the energy storage capacitor is respectively connected to the second working power supply and the first end of the first control switch, the second end of the first control switch is connected to the control end of the first switching device, the control end of the first control switch is connected to the output end of the pulse control unit, and the input end of the pulse control unit is connected to the output end of the first comparator; the pulse control unit is used to control the first control switch to be turned on for a preset time when the output end of the first comparator outputs a voltage rising edge.

[0008] In one embodiment, the reverse protection switch circuit also includes a current limiting module; the current limiting module is connected between the second end of the reverse protection switch module and the output end of the reverse protection switch circuit; the current limiting module is used to control the output current of the reverse protection switch circuit based on a reference current.

[0009] In one embodiment, the current limiting module includes a third switch device, a fourth switch device, a second comparator and a current limiting unit; the first end of the third switch device is connected to the second end of the reverse protection switch module, the second end of the third switch device is connected to the output end of the reverse protection switch circuit, the control end of the third switch device is connected to the output end of the second comparator, the first input end of the second comparator is connected to the first end of the third switch device, the second input end of the second comparator is respectively connected to the first end of the fourth switch device and the first end of the current limiting unit, the second end of the current limiting unit is grounded, the second end of the fourth switch device is connected to the input end of the reverse protection switch circuit, and the control end of the fourth switch device is connected to the control end of the first switch device; the current limiting unit is used to control the reference current flowing through the fourth switch device, and the second comparator is used to control the current flowing through the third switch device based on the voltage of the first input end of the second comparator and the voltage of the second input end of the second comparator.

[0010] In one embodiment, the third switch device and the fourth switch device are both N-type MOS tubes.

[0011] In one embodiment, the fast recovery charging module also includes a second control switch and a unidirectional conductive device; the positive electrode of the unidirectional conductive device is connected to the control end of the third switch device, the negative electrode of the unidirectional conductive device is connected to the first end of the second control switch, the second end of the second control switch is connected to the control end of the first switch device, and the control end of the second control switch is connected to the output end of the first comparator; the first switch device is used to turn on when the first comparator outputs a high level.

[0012] A second aspect of an embodiment of the present application provides a power supply device, comprising the reverse protection switch circuit as described above.

[0013] A third aspect of an embodiment of the present application provides an electronic device, comprising the reverse protection switch circuit as described above.

[0014] The beneficial effect of the embodiment of the present application compared with the prior art is that the quick recovery charging module can accelerate the speed of the reverse protection switch module recovering from the off state to the on state, thereby avoiding the reverse protection switch circuit from having insufficient power supply capacity to the load when exiting the reverse protection state, causing the load to stop working or fail. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the structure of a reverse protection switch circuit provided in an embodiment of the present application;

[0016] Figure 2Another structural schematic diagram of a reverse protection switch circuit provided in an embodiment of the present application;

[0017] Figure 3 A circuit diagram of a reverse protection switch circuit provided in an embodiment of the present application;

[0018] Figure 4 A schematic diagram of the structure of a power supply device provided in one embodiment of the present application;

[0019] Figure 5 A schematic diagram of the structure of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0021] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0023] Figure 1 The structure diagram of the reverse protection switch circuit provided by an embodiment of the present application is shown. For the convenience of description, only the part related to the present embodiment is shown, which is described in detail as follows:

[0024] The reverse protection switch circuit 10 is used to protect the power supply 20 when the voltage of the load 30 is greater than the voltage of the power supply 20. The input end of the reverse protection switch circuit 10 is used to connect the power supply 20, and the output end of the reverse protection switch circuit 10 is used to connect the load 30. The reverse protection switch circuit 10 includes: a reverse protection switch module 100 and a fast recovery charging module 200.

[0025] The first end of the reverse protection switch module 100 is connected to the input end of the reverse protection switch circuit 10, and the second end of the reverse protection switch module 100 is connected to the output end of the reverse protection switch circuit 10. A fast recovery charging module 200, the fast recovery charging module 200 is connected to the reverse protection switch module 100. The reverse protection switch module 100 is used to shut down when the voltage at the second end of the reverse protection switch module 100 is greater than the first end of the reverse protection switch module 100. The fast recovery charging module 200 is used to charge when the reverse protection switch module 100 is turned on, and to provide a recovery voltage to the reverse protection switch module 100 when the reverse protection switch module 100 is restored from the off state to the on state. The recovery voltage is used to speed up the speed at which the reverse protection switch module 100 is restored from the off state to the on state.

[0026] It should be noted that the reverse protection switch module 100 is in a conducting state under normal working conditions to transmit electric energy to the load 30. When the voltage at the output end of the reverse protection switch circuit 10 fluctuates, causing its voltage to be greater than the voltage at the input end, the reverse protection switch module 100 can be turned off in time to achieve reverse protection. After the voltage at the output end of the reverse protection switch circuit 10 returns to normal, the reverse protection switch module 100 can be turned on again.

[0027] If the reverse protection switch module 100 takes too long to be turned on again, the output voltage of the reverse protection switch circuit 10 is likely to be much lower than the input voltage, causing power failure of the load 30. The fast recovery charging module 200 can speed up the speed at which the reverse protection switch module 100 recovers from the off state to the on state, thereby preventing the reverse protection switch circuit 10 from having insufficient power supply capacity to the load 30 when exiting the reverse protection state, causing the load 30 to be powered off for a long time, thereby causing the load 30 to stop working or malfunction.

[0028] In some embodiments, the power source 20 may be a battery pack or other DC power source 20. The load 30 may be an electrical device such as a motor.

[0029] In one embodiment, if Figure 2 As shown, the reverse protection switch circuit 10 further includes a current limiting module 300. The current limiting module 300 is connected between the second end of the reverse protection switch module 100 and the output end of the reverse protection switch circuit 10. The current limiting module 300 is used to control the output current of the reverse protection switch circuit 10 based on the reference current.

[0030] It can be understood that by controlling the output current of the reverse protection switch circuit 10 through the current limiting module 300, the load 30 can be protected. When the output end of the reverse protection switch circuit 10 is grounded or the power of the load 30 is too large, the current limiting module 300 prevents excessive current from damaging the circuit.

[0031] In one embodiment, if Figure 3 As shown, the reverse protection switch circuit 10 includes a first working power source 400, and the reverse protection switch module 100 includes a first switch device Q1, a second switch device Q2 and a first comparator U1.

[0032] The first end of the first switch device Q1 is the first end of the reverse protection switch module 100, the second end of the first switch device Q1 is the second end of the reverse protection switch module 100, and the control end of the first switch device Q1 is connected to the first working power supply 400. The first end of the second switch device Q2 is connected to the first end of the first switch device Q1, the second end of the second switch device Q2 is connected to the control end of the first switch device Q1, and the control end of the second switch device Q2 is connected to the output end of the first comparator U1. The first input end of the first comparator U1 is connected to the input end of the reverse protection switch circuit 10, and the second input end of the first comparator U1 is connected to the output end of the reverse protection switch circuit 10. The first comparator U1 is used to control the second switch device Q2 to turn on when the voltage at the second input end of the first comparator U1 is greater than the voltage at the first input end of the first comparator U1.

[0033] It can be understood that when the second switch device Q2 is turned off, the first working power supply 400 can provide the first working voltage to the control terminal of the first switch device Q1 to turn on the first switch device Q1. When the second switch device Q2 is turned on, the voltage of the control terminal of the first switch device Q1 is equal to the voltage of the first terminal of the first switch device Q1, and the first switch device Q1 cannot be turned on. The first comparator U1 can control the first switch device Q1 by controlling the on and off of the second switch device Q2, thereby achieving reverse protection.

[0034] In one embodiment, the first switch device Q1 is an N-type MOS transistor, and the second switch device Q2 is a P-type MOS transistor.

[0035] It is understandable that when the first comparator U1 outputs a high level, the second switch device Q2 is turned off. When the voltage at the second input terminal of the first comparator U1 is greater than the voltage at the first input terminal of the first comparator U1, the first comparator U1 outputs a low level, thereby controlling the second switch device Q2 to turn on.

[0036] In one embodiment, if Figure 3 As shown, the reverse protection switch circuit 10 includes a second working power supply 500, and the fast recovery charging module 200 includes a storage capacitor C1, a first control switch S1 and a pulse control unit 210. The pulse control unit 210 may include a microcontroller such as a chip or a single chip microcomputer.

[0037] The first end of the energy storage capacitor C1 is connected to the input end of the reverse protection switch circuit 10, the second end of the energy storage capacitor C1 is respectively connected to the second working power supply 500 and the first end of the first control switch S1, the second end of the first control switch S1 is connected to the control end of the first switch device Q1, the control end of the first control switch S1 is connected to the output end of the pulse control unit 210, and the input end of the pulse control unit 210 is connected to the output end of the first comparator U1. The pulse control unit 210 is used to control the first control switch S1 to be turned on for a preset time when the output end of the first comparator U1 outputs a voltage rising edge.

[0038] It is understandable that when the first control switch S1 is turned off, the second working power supply 500 can charge the energy storage capacitor C1. The preset duration can be adjusted by configuring the pulse control unit 210.

[0039] Exemplarily, in some embodiments, the pulse control unit 210 includes a One-Shot module.

[0040] The first comparator U1 outputs a voltage rising edge (the first comparator U1 changes from outputting a low level to outputting a high level), which means that after the reverse protection switch circuit 10 triggers the reverse protection, the voltage at the output end of the reverse protection switch circuit 10 has decreased and returned to normal. After the first control switch S1 is turned on, the energy storage capacitor C1 can release the stored electric energy, increase the voltage at the control end of the first switch device Q1, increase the conduction speed of the first switch device Q1, and thus increase the recovery speed of the reverse protection switch circuit 10.

[0041] In one embodiment, the current limiting module 300 includes a third switch device Q3, a fourth switch device Q4, a second comparator U2 and a current limiting unit 310. The first end of the third switch device Q3 is connected to the second end of the reverse protection switch module 100, the second end of the third switch device Q3 is connected to the output end of the reverse protection switch circuit 10, the control end of the third switch device Q3 is connected to the output end of the second comparator U2, the first input end of the second comparator U2 is connected to the first end of the third switch device Q3, the second input end of the second comparator U2 is respectively connected to the first end of the fourth switch device Q4 and the first end of the current limiting unit 310, the second end of the current limiting unit 310 is grounded, the second end of the fourth switch device Q4 is connected to the input end of the reverse protection switch circuit 10, and the control end of the fourth switch device Q4 is connected to the control end of the first switch device Q1. The current limiting unit 310 is used to control the reference current flowing through the fourth switch device Q4, and the second comparator U2 is used to control the current flowing through the third switch device Q3 based on the voltage of the first input end of the second comparator U2 and the voltage of the second input end of the second comparator U2.

[0042] It can be understood that, when the reference current is fixed, the negative feedback loop composed of the second comparator U2 can control the on-resistance of the third switching device Q3 based on the voltage at the first input terminal and the voltage at the second input terminal, thereby adjusting the current flowing through the third switching device Q3, that is, adjusting the output current of the reverse protection switch circuit 10.

[0043] At the same time, when the reverse protection switch circuit 10 performs reverse protection, the second comparator U2 can pull up the voltage of the control terminal of the third switch device Q3 to clamp the voltage of the control terminal of the third switch device Q3.

[0044] In one embodiment, the third switch device Q3 and the fourth switch device Q4 are both N-type MOS transistors.

[0045] In some embodiments, the on-resistance of the fourth switch device Q4 is equal to the on-resistance of the first switch device Q1. Therefore, the second comparator U2 can keep the voltage of the first input terminal and the voltage of the second input terminal of the second comparator U2 equal by continuously adjusting the on-resistance of the third switch device Q3. When the on-resistance of the fourth switch device Q4 is equal to the on-resistance of the first switch device Q1, the output current of the reverse protection switch circuit 10 can be equal to the reference current.

[0046] In some embodiments, the current limiting unit 310 includes a current source.

[0047] In one embodiment, if Figure 3 As shown, the fast recovery charging module 200 also includes a second control switch S2 and a unidirectional conductive device D1. The positive electrode of the unidirectional conductive device D1 is connected to the control end of the third switch device Q3, the negative electrode of the unidirectional conductive device D1 is connected to the first end of the second control switch S2, the second end of the second control switch S2 is connected to the control end of the first switch device Q1, and the control end of the second control switch S2 is connected to the output end of the first comparator U1. The first switch device Q1 is used to turn on when the first comparator U1 outputs a high level.

[0048] It can be understood that when the second control switch S2 is turned on, the electric energy output by the second comparator U2 can also charge the control terminal of the first switch device Q1, thereby further accelerating the turn-on speed of the first switch device Q1.

[0049] Figure 4 A schematic diagram of the structure of a power supply device provided in an embodiment of the present application is shown. For the sake of convenience, only the parts related to the present embodiment are shown, which are described in detail as follows:

[0050] The power supply device 40 includes a power supply 20 and a reverse protection switch circuit 10 as in any one of the above embodiments.

[0051] Exemplarily, the power supply device 40 can supply power to various monitoring instruments and equipment.

[0052] Figure 5 A schematic diagram of the structure of an electronic device provided by an embodiment of the present application is shown. For the sake of convenience, only the parts related to the present embodiment are shown, which are described in detail as follows:

[0053] The electronic device 50 includes the reverse protection switch circuit 10 according to any one of the above embodiments.

[0054] The electronic device 50 may specifically be various monitoring instruments and equipment.

[0055] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0056] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0057] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A reverse protection switch circuit, characterized in that: The input end of the reverse protection switch circuit is used to connect to a power supply, and the output end of the reverse protection switch circuit is used to connect to a load. The reverse protection switch circuit includes: A reverse protection switch module, wherein a first end of the reverse protection switch module is connected to an input end of the reverse protection switch circuit, and a second end of the reverse protection switch module is connected to an output end of the reverse protection switch circuit; A fast recovery charging module, the fast recovery charging module is connected to the reverse protection switch module; The reverse protection switch module is used to turn off when the voltage at the second end of the reverse protection switch module is greater than the voltage at the first end of the reverse protection switch module; the fast recovery charging module is used to charge when the reverse protection switch module is turned on, and to provide a recovery voltage to the reverse protection switch module when the reverse protection switch module is restored from the off state to the on state; The recovery voltage is used to accelerate the speed at which the reverse protection switch module recovers from the off state to the on state; The reverse protection switch circuit includes a first working power supply, and the reverse protection switch module includes a first switch device, a second switch device and a first comparator; The first end of the first switch device is the first end of the reverse protection switch module, the second end of the first switch device is the second end of the reverse protection switch module, and the control end of the first switch device is connected to the first working power supply; The first end of the second switch device is connected to the first end of the first switch device, the second end of the second switch device is connected to the control end of the first switch device, and the control end of the second switch device is connected to the output end of the first comparator; The first input terminal of the first comparator is connected to the input terminal of the reverse protection switch circuit, and the second input terminal of the first comparator is connected to the output terminal of the reverse protection switch circuit; The first comparator is used for controlling the second switch device to be turned on when the voltage at the second input terminal of the first comparator is greater than the voltage at the first input terminal of the first comparator.

2. The reverse protection switch circuit according to claim 1, characterized in that: The first switch device is an N-type MOS tube, and the second switch device is a P-type MOS tube.

3. The reverse protection switch circuit according to claim 1 or 2, characterized in that: The reverse protection switch circuit includes a second working power supply, and the fast recovery charging module includes an energy storage capacitor, a first control switch and a pulse control unit; The first end of the energy storage capacitor is connected to the input end of the reverse protection switch circuit, the second end of the energy storage capacitor is connected to the second working power supply and the first end of the first control switch respectively, the second end of the first control switch is connected to the control end of the first switch device, the control end of the first control switch is connected to the output end of the pulse control unit, and the input end of the pulse control unit is connected to the output end of the first comparator; The pulse control unit is used to control the first control switch to be turned on for a preset time period when the output end of the first comparator outputs a voltage rising edge.

4. The reverse protection switch circuit according to claim 1 or 2, characterized in that: The reverse protection switch circuit also includes a current limiting module; The current limiting module is connected between the second end of the reverse protection switch module and the output end of the reverse protection switch circuit; The current limiting module is used to control the output current of the reverse protection switch circuit based on a reference current.

5. The reverse protection switch circuit according to claim 4, characterized in that: The current limiting module includes a third switch device, a fourth switch device, a second comparator and a current limiting unit; The first end of the third switch device is connected to the second end of the reverse protection switch module, the second end of the third switch device is connected to the output end of the reverse protection switch circuit, the control end of the third switch device is connected to the output end of the second comparator, the first input end of the second comparator is connected to the first end of the third switch device, the second input end of the second comparator is respectively connected to the first end of the fourth switch device and the first end of the current limiting unit, the second end of the current limiting unit is grounded, the second end of the fourth switch device is connected to the input end of the reverse protection switch circuit, and the control end of the fourth switch device is connected to the control end of the first switch device; The current limiting unit is used to control the reference current flowing through the fourth switching device, and the second comparator is used to control the current flowing through the third switching device based on the voltage of the first input terminal of the second comparator and the voltage of the second input terminal of the second comparator.

6. The reverse protection switch circuit according to claim 5, characterized in that: The third switch device and the fourth switch device are both N-type MOS tubes.

7. The reverse protection switch circuit according to claim 5, characterized in that: The fast recovery charging module also includes a second control switch and a unidirectional conductive device; The positive electrode of the unidirectional conductive device is connected to the control end of the third switch device, the negative electrode of the unidirectional conductive device is connected to the first end of the second control switch, the second end of the second control switch is connected to the control end of the first switch device, and the control end of the second control switch is connected to the output end of the first comparator; The first switch device is used to be turned on when the first comparator outputs a high level.

8. A power supply device, characterized in that: It comprises a reverse protection switch circuit as described in any one of claims 1 to 7.

9. An electronic device, characterized in that: It comprises a reverse protection switch circuit as described in any one of claims 1 to 7.

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