Reverse connection prevention protection circuit, power supply circuit and automobile

Abstract

The utility model discloses an anti-reverse connection protection circuit, a power supply circuit and an automobile. The anti-reverse connection protection circuit comprises an anti-reverse connection module, a voltage comparison module and a control module, the anti-reverse connection module is arranged between the signal input end and the signal output end; a first end of the voltage comparison module is connected with the signal input end and is used for acquiring a first output voltage; a second end of the voltage comparison module is connected with the signal output end and is used for acquiring a second output voltage; the third end of the voltage comparison module is connected with the control module, and the voltage comparison module is used for outputting a control signal to the control module according to the first output voltage and the second output voltage. The anti-reverse connection protection circuit can detect whether the voltage drop condition occurs in the connected power supply circuit in real time, and when the voltage drop condition occurs, the power supply circuit stops supplying power to the power supply circuit, so that the electrolytic capacitor in the power supply circuit is prevented from being charged repeatedly.

Description

Technical Field

[0001] The utility model relates to the technical field of anti-reverse connection circuits, in particular to an anti-reverse connection protection circuit, a power supply circuit and an automobile. Background Art

[0002] In the power supply circuit of an electrical load, an anti-reverse connection circuit is usually arranged at the input end of the power supply circuit to prevent the subsequent circuit from being damaged or burned out due to reverse polarity connection when the electrical load is connected to an external power supply circuit.

[0003] During the power supply process of connecting to an external power supply circuit, the voltage at the signal input end of the anti-reverse connection circuit often drops suddenly due to unstable power supply voltage. At this time, the voltage at the signal output end of the anti-reverse connection circuit also drops accordingly. If there is an electrolytic capacitor in the subsequent stage of the anti-reverse connection circuit, this voltage drop will cause the electrolytic capacitor in the switching power supply circuit to charge repeatedly, resulting in the electrolytic capacitor heating up and affecting the service life of the electrolytic capacitor. Content of the Utility Model

[0004] An embodiment of the utility model provides an anti-reverse connection protection circuit, a power supply circuit and an automobile, so as to solve the problem that when the input voltage of the existing anti-reverse connection circuit drops, the output voltage also drops accordingly, which easily causes the electrolytic capacitor in the subsequent circuit to heat up.

[0005] An embodiment of the utility model provides an anti-reverse connection protection circuit, including an anti-reverse connection module, a voltage comparison module and a control module;

[0006] The anti-reverse connection module is arranged between the signal input end and the signal output end;

[0007] The first end of the voltage comparison module is connected to the signal input end for obtaining a first output voltage; the second end of the voltage comparison module is connected to the signal output end for obtaining a second output voltage; the third end of the voltage comparison module is connected to the control module for outputting a control signal to the control module according to the first output voltage and the second output voltage;

[0008] The control module is connected to the anti-reverse connection module for turning off or not turning off the anti-reverse connection module according to the control signal.

[0009] Preferably, the anti-reverse connection module includes a first control tube and a driving circuit;

[0010] The first end of the first control tube is connected to the signal input end, the second end of the first control tube is connected to the signal output end, and the third end of the first control tube is connected to the driving circuit;

[0011] The driving circuit is connected to the signal output end and is also used to be connected to a driving chip. According to the voltage at the signal output end and the driving signal output by the driving chip, it controls the first control tube to conduct or turn off;

[0012] The third end of the first control tube is also connected to the control module and is used to turn off or not turn off under the control of the control module.

[0013] Preferably, the driving circuit includes a first capacitor, a second capacitor, a first diode, a second diode and a voltage stabilizing diode;

[0014] The first end of the first capacitor is used to be connected to the driving chip. The second end of the first capacitor is connected to the cathode of the first diode, and the anode of the first diode is connected to the signal output end;

[0015] The cathode of the voltage stabilizing diode is connected to the second end of the first capacitor. The anode of the voltage stabilizing diode is connected to the anode of the second diode, and the cathode of the second diode is grounded;

[0016] The first end of the second capacitor is connected to the connection node between the voltage stabilizing diode and the first capacitor, and the second end of the second capacitor is grounded;

[0017] The third end of the first control tube is connected to the connection node between the voltage stabilizing diode and the first capacitor.

[0018] Preferably, the driving circuit further includes a first resistor and a second resistor;

[0019] The first end of the first resistor is connected to the second end of the first capacitor, and the second end of the first resistor is connected to the cathode of the voltage stabilizing diode;

[0020] The first end of the second resistor is connected to the third end of the first control tube, and the second end of the second resistor is connected to the cathode of the voltage stabilizing diode.

[0021] Preferably, the voltage comparison module includes a comparator;

[0022] The inverting input terminal of the comparator is connected to the connection node between the reverse connection prevention module and the signal input end;

[0023] The non-inverting input terminal of the comparator is connected to the connection node between the reverse connection prevention module and the signal output end;

[0024] The output terminal of the comparator is connected to the control module and is used to output a first control signal to the control module when the first output voltage is less than the second output voltage, and output a second control signal to the control module when the first output voltage is not less than the second output voltage;

[0025] The control module is configured to turn off the reverse connection prevention module according to the first control signal, and stop turning off the reverse connection prevention module according to the second control signal.

[0026] Preferably, the control module includes a second control transistor;

[0027] A first end of the second control transistor is connected to the reverse connection prevention module, a second end of the second control transistor is connected to the voltage comparison module, and a third end of the second control transistor is grounded.

[0028] Preferably, the control module further includes a third resistor and a third diode;

[0029] A first end of the third resistor is connected to the signal input terminal, a second end of the third resistor is connected to an anode of the third diode, and a cathode of the third diode is connected to the first end of the second control transistor.

[0030] Preferably, the control module further includes a fourth diode;

[0031] An anode of the fourth diode is connected to the reverse connection prevention module, and a cathode of the fourth diode is connected to the first end of the second control transistor.

[0032] An embodiment of the present invention further provides a power supply circuit, including an input interface, an electrolytic capacitor, and the above-mentioned reverse connection prevention protection circuit;

[0033] The input interface is connected to a signal input terminal of the reverse connection prevention protection circuit, and the input interface is further configured to connect to a power supply circuit;

[0034] A first end of the electrolytic capacitor is connected to a signal output terminal of the reverse connection prevention protection circuit, and a second end of the electrolytic capacitor is grounded.

[0035] An embodiment of the present invention further provides an automobile, characterized in that it includes the above-mentioned power supply circuit.

[0036] The reverse connection prevention protection circuit, the power supply circuit, and the automobile provided by the embodiments of the present invention can, by adding a voltage comparison module and a control module to the reverse connection prevention protection circuit, detect in real time whether there is a voltage drop in the power supply circuit connected to the reverse connection prevention protection circuit, and when there is a voltage drop, stop the power supply circuit from supplying power to the power supply circuit, prevent the electrolytic capacitor in the power supply circuit from being repeatedly charged, extend the life of the electrolytic capacitor, and avoid causing a heating phenomenon. Description of the Drawings

[0037] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0038] Figure 1 is a schematic block diagram of an anti-reverse connection protection circuit in an embodiment of the present invention;

[0039] Figure 2 is a schematic circuit diagram of an anti-reverse connection protection circuit in an embodiment of the present invention.

[0040] In the figure: 1. Anti-reverse connection module; 11. Driving circuit; 2. Voltage comparison module; 3. Control module. Detailed implementation manners

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0042] It should be understood that the present invention can be implemented in different forms and should not be construed as limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. In the drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated. The same reference numerals denote the same elements throughout the drawings.

[0043] It should be understood that when an element or layer is referred to as being "on", "adjacent to", "connected to" or "coupled to" another element or layer, it can be directly on, adjacent to, connected or coupled to the other element or layer, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on", "directly adjacent to", "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Thus, without departing from the teachings of the present invention, the first element, component, region, layer or part discussed below may be denoted as the second element, component, region, layer or part.

[0044] Spatial relationship terms such as "under", "below", "beneath", "underneath", "above", "over", etc. are used herein for convenience in describing the relationship of one element or feature shown in the figures to other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relationship terms are intended to include different orientations of the device in use and operation. For example, if the device in the figures is flipped, then an element or feature described as "under" or "beneath" or "underneath" another element or feature will be oriented "over" the other element or feature. Thus, the exemplary terms "under" and "beneath" can include both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatial descriptors used herein are to be interpreted accordingly.

[0045] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present invention. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, specify the presence of the stated features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups. As used herein, the term "and / or" includes any and all combinations of the associated listed items.

[0046] In order to fully understand the present invention, detailed structures and steps will be set forth in the following description to explain the technical solutions proposed by the present invention. The preferred embodiments of the present invention are described in detail below. However, in addition to these detailed descriptions, the present invention may have other embodiments.

[0047] An embodiment of the present utility model provides an anti-reverse connection protection circuit, which includes an anti-reverse connection module 1, a voltage comparison module 2, and a control module 3; the anti-reverse connection module 1 is arranged between the signal input terminal Vin and the signal output terminal Vout; the first end of the voltage comparison module 2 is connected to the signal input terminal Vin and is used to obtain a first output voltage; the second end of the voltage comparison module 2 is connected to the signal output terminal Vout and is used to obtain a second output voltage; the third end of the voltage comparison module 2 is connected to the control module 3 and is used to output a control signal to the control module 3 according to the first output voltage and the second output voltage; the control module 3 is connected to the anti-reverse connection module 1 and is used to turn off or not turn off the anti-reverse connection module 1 according to the control signal.

[0048] As an example, the anti-reverse connection protection circuit can be arranged at the input end of the power supply circuit of a certain electrical product, including a signal input terminal Vin and a signal output terminal Vout. The signal input terminal Vin can be connected to an external power supply circuit through the input interface of the power supply circuit to receive the power supply voltage output by the power supply circuit. The signal output terminal Vout is used to be connected to the subsequent power supply circuit. An electrolytic capacitor C3 is also connected at the connection node between the signal output terminal Vout and the subsequent power supply circuit for filtering and energy storage to make the voltage output to the subsequent circuit smoother and more stable. The anti-reverse connection protection circuit further includes an anti-reverse connection module 1, which is arranged between the signal input terminal Vin and the signal output terminal Vout and is used to conduct when the power supply circuit is connected to the signal input terminal Vin in the forward direction, so that the power supply circuit supplies power to the power supply circuit of the electrical product, and disconnects when the power supply circuit is connected to the signal input terminal Vin in the reverse direction, so that the power supply circuit stops supplying power to the power supply circuit, preventing damage to the circuit caused by the reverse connection of the power supply circuit. The anti-reverse connection protection circuit further includes a voltage comparison module 2 and a control module 3. The first end of the voltage comparison module 2 is connected to the connection node between the anti-reverse connection module 1 and the signal input terminal Vin and is used to obtain a first output voltage. The second end of the voltage comparison module 2 is connected to the connection node between the anti-reverse connection module 1 and the signal output terminal Vout and is used to obtain a second output voltage. The third end of the voltage comparison module 2 is connected to the control module 3, and the control module 3 is connected to the anti-reverse connection module 1. The voltage comparison module 2 is used to output a control signal to the control module 3 according to the first output voltage and the second output voltage, and the control module 3 controls to turn off or not turn off the anti-reverse connection module 1 according to this control signal. Specifically, the voltage comparison module 2 can output a first control signal to the control module 3 when the first output voltage is less than the second output voltage, so that the control module 3 controls to turn off the anti-reverse connection module 1 according to the first control signal, and the power supply circuit stops supplying power to the power supply circuit; the voltage comparison module 2 can output a second control signal to the control module 3 when the first output voltage is not less than the second output voltage, so that the control module 3 stops turning off the anti-reverse connection module 1 according to the second control signal.

[0049] When there is a voltage drop in the power supply circuit connected to the signal input terminal Vin, that is, when the supply voltage suddenly decreases, the signal output terminal Vout still maintains the voltage at the previous moment, resulting in a voltage difference across the reverse connection protection circuit. The first output voltage input to the voltage comparison module 2 is less than the second output voltage. At this time, the voltage comparison module 2 outputs a first control signal to the control module 3, causing the control module 3 to turn off the reverse connection protection module 1 according to this control signal, thereby stopping the power supply circuit from supplying power to the external load. When the voltage of the power supply circuit returns to the normal supply voltage, the first output voltage input to the voltage comparison module 2 is no longer less than the second output voltage. At this time, the voltage comparison module 2 outputs a second control signal to the control module 3, causing the control module 3 to stop turning off the reverse connection protection module 1 according to this second control signal.

[0050] In this example, by adding a voltage comparison module 2 and a control module 3 to the reverse connection protection circuit, it is possible to detect in real time whether there is a voltage drop in the power supply circuit connected to the reverse connection protection circuit. When there is a voltage drop, the power supply circuit stops supplying power to the power supply circuit, preventing the electrolytic capacitor C3 in the power supply circuit from being repeatedly charged, extending the life of the electrolytic capacitor C3, and avoiding the occurrence of heating phenomena.

[0051] In one embodiment, the reverse connection protection module 1 includes a first control transistor Q1 and a driving circuit 11. The first end of the first control transistor Q1 is connected to the signal input terminal Vin, the second end of the first control transistor Q1 is connected to the signal output terminal Vout, and the third end of the first control transistor Q1 is connected to the driving circuit 11. The driving circuit 11 is connected to the signal output terminal Vout and is used to control the conduction or cutoff of the first control transistor Q1 according to the voltage of the signal output terminal Vout and also to connect to a driving chip and according to the voltage of the signal output terminal Vout and the driving signal output by the driving chip. The third end of the first control transistor Q1 is also connected to the control module 3 and is used to be turned off or not turned off under the control of the control module 3.

[0052] As an example, the reverse connection prevention module 1 includes a first control transistor Q1 and a driving circuit 11. The first control transistor Q1 can be an NMOS transistor. The first end of the first control transistor Q1 is the source of the NMOS transistor, the second end of the first control transistor Q1 is the drain of the NMOS transistor, and the third end of the first control transistor Q1 is the gate of the NMOS transistor. The first end of the first control transistor Q1 is connected to the signal input terminal Vin, the second end of the first control transistor Q1 is connected to the signal output terminal Vout, and the third end of the first control transistor Q1 is connected to the driving circuit 11. The driving circuit 11, which is connected to the signal output terminal Vout and the DC-DC-SW terminal of the driving chip, can control the conduction or cutoff of the first control transistor Q1 according to the voltage of the signal output terminal Vout and the driving signal output by the driving chip. Specifically, when the power supply circuit is connected to the signal input terminal Vin in the forward direction, the power supply voltage output by the power supply circuit can reach the signal output terminal Vout through the body diode of the NMOS transistor. The driving circuit 11 controls the first control transistor Q1 to conduct according to the current voltage of the signal output terminal Vout and the driving signal output by the driving chip, so that the power supply circuit supplies power to the power supply circuit. When the power supply circuit is connected to the signal output terminal Vout in the reverse direction, the power supply voltage output by the power supply circuit cannot reach the signal output terminal Vout through the body diode of the NMOS transistor. The driving circuit 11 cannot make the first control transistor Q1 conduct only according to the driving signal output by the driving chip, so that the power supply circuit stops supplying power to the power supply circuit. The third end of the first control transistor Q1 is also connected to the control module 3. When the first output voltage is less than the second output voltage, the control module 3 can turn off the first control transistor Q1 according to the first control signal output by the voltage comparison module 2. When the first output voltage is not less than the second output voltage, the control module 3 can stop turning off the first control transistor Q1 according to the second control signal output by the voltage comparison module 2, so that the first control transistor Q1 returns to the state driven and controlled by the driving circuit 11.

[0053] In one embodiment, the driving circuit 11 includes a first capacitor C1, a second capacitor C2, a first diode D1, a second diode D2, and a zener diode D5. The first end of the first capacitor C1 is used to be connected to the driving chip. The second end of the first capacitor C1 is connected to the cathode of the first diode D1, and the anode of the first diode D1 is connected to the signal output terminal Vout. The cathode of the zener diode D5 is connected to the second end of the first capacitor C1, the anode of the zener diode D5 is connected to the anode of the second diode D2, and the cathode of the second diode D2 is grounded. The first end of the second capacitor C2 is connected to the connection node between the zener diode D5 and the first capacitor C1, and the second end of the second capacitor C2 is grounded. The third end of the first control transistor Q1 is connected to the connection node between the zener diode D5 and the first capacitor C1.

[0054] As an example, the driving circuit 11 includes a first capacitor C1, a second capacitor C2, a first diode D1, a second diode D2, and a voltage stabilizing diode D5. The first end of the first capacitor C1 is used to be connected to the DC-DC-SW terminal of a driving chip. This driving chip can be a chip in the power supply circuit and can output an AC driving signal, such as a PWM signal, to the driving circuit 11 through the DC-DC-SW terminal. The second end of the first capacitor C1 is connected to the cathode of the first diode D1, and the anode of the first diode D1 is connected to the signal output terminal Vout; the cathode of the voltage stabilizing diode D5 is connected to the second end of the first capacitor C1, the anode of the voltage stabilizing diode D5 is connected to the anode of the second diode D2, and the cathode of the second diode D2 is grounded; the first end of the second capacitor C2 is connected to the connection node between the voltage stabilizing diode D5 and the first capacitor C1, and the second end of the second capacitor C2 is grounded; the third end of the first control transistor Q1 is connected to the connection node between the voltage stabilizing diode D5 and the first capacitor C1. The first capacitor C1, the second capacitor C2, the first diode D1, the second diode D2, and the voltage stabilizing diode D5 form a voltage doubling rectifier circuit. By utilizing the energy storage effect of the first capacitor C1 and the second capacitor C2 and the unidirectional conductivity of the first diode D1 and the second diode D2, the PWM signal output by the driving chip and the voltage output by the signal output terminal Vout are converted into a DC driving voltage with a higher voltage value to drive the first control transistor Q1 and control the conduction of the first control transistor Q1. When the power supply circuit is connected to the signal input terminal Vin in the forward direction, the PWM signal output by the driving chip and the voltage output by the signal output terminal Vout supply power to the driving circuit 11 at the same time, and the voltage output to the first control transistor Q1 can control the conduction of the first control transistor Q1. When the power supply circuit is connected to the signal input terminal Vin in the reverse direction, only the PWM signal output by the driving chip supplies power to the driving circuit 11, and the voltage output to the first control transistor Q1 is not sufficient to control the conduction of the first control transistor Q1, which can achieve the effect of preventing reverse connection.

[0055] In an embodiment, the driving circuit 11 further includes a first resistor R1 and a second resistor R2; the first end of the first resistor R1 is connected to the second end of the first capacitor C1, and the second end of the first resistor R1 is connected to the cathode of the voltage stabilizing diode D5; the first end of the second resistor R2 is connected to the third end of the first control transistor Q1, and the second end of the second resistor R2 is connected to the cathode of the voltage stabilizing diode D5.

[0056] As an example, the driving circuit 11 further includes a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is connected to the second end of the first capacitor C1, and the second end of the first resistor R1 is connected to the cathode of the voltage stabilizing diode D5; the first end of the second resistor R2 is connected to the third end of the first control transistor Q1, and the second end of the second resistor R2 is connected to the cathode of the voltage stabilizing diode D5. Both the first resistor R1 and the second resistor R2 play the roles of voltage division and current limiting.

[0057] In one embodiment, the voltage comparison module 2 includes a comparator U1; the inverting input terminal of the comparator U1 is connected to the connection node between the reverse connection prevention module 1 and the signal input terminal Vin; the non-inverting input terminal of the comparator U1 is connected to the connection node between the reverse connection prevention module 1 and the signal output terminal Vout; the output terminal of the comparator U1 is connected to the control module 3, and is used to output a first control signal to the control module 3 when the first output voltage is less than the second output voltage, and output a second control signal to the control module 3 when the first output voltage is not less than the second output voltage; the control module 3 is used to turn off the reverse connection prevention module 1 according to the first control signal, and stop turning off the reverse connection prevention module 1 according to the second control signal.

[0058] As an example, the voltage comparison module 2 includes a comparator U1. The inverting input terminal of the comparator U1 is connected to the connection node between the reverse connection prevention module 1 and the signal input terminal Vin, the non-inverting input terminal of the comparator U1 is connected to the connection node between the reverse connection prevention module 1 and the signal output terminal Vout, and the output terminal of the comparator U1 is connected to the control module 3, and can output a first control signal to the control module 3 when the first output voltage is less than the first output voltage, so that the control module 3 controls the reverse connection prevention module 1 to turn off according to the first control signal; it can also output a second control signal to the control module 3 when the first output voltage is not less than the second output voltage, so that the control module 3 stops turning off the reverse connection prevention module 1 according to the second control signal, and makes the first control transistor Q1 in the reverse connection prevention module 1 return to the state controlled by the drive circuit 11.

[0059] In one embodiment, the control module 3 includes a second control transistor Q2; the first end of the second control transistor Q2 is connected to the reverse connection prevention module 1, the second end of the second control transistor Q2 is connected to the voltage comparison module 2, and the third end of the second control transistor Q2 is grounded.

[0060] As an example, the control module 3 includes a second control transistor Q2. The second control transistor Q2 can be an NPN triode. The first end of the second control transistor Q2 is the collector of the triode, the second end of the second control transistor Q2 is the gate of the triode, and the third end of the second control transistor Q2 is the emitter of the triode. The first end of the second control transistor Q2 is connected to the third end of the first control transistor Q1 in the reverse connection prevention module 1, the second end of the second control transistor Q2 is connected to the voltage comparison module 2, and the third end of the second control transistor Q2 is grounded. The second control transistor Q2 can be turned on under the control of the first control signal output by the voltage comparison module 2, pull down the third end of the first control transistor Q1 in the reverse connection prevention module 1, that is, the gate of the NMOS transistor, to the ground, so that the first control transistor Q1 is turned off and the reverse connection prevention module 1 is turned off; the second control transistor Q2 can also be turned off under the control of the second control signal output by the voltage comparison module 2, stop turning off the first control transistor Q1, and make the first control transistor Q1 return to the state controlled by the drive circuit 11.

[0061] In one embodiment, the control module 3 further includes a third resistor R3 and a third diode D3; a first end of the third resistor R3 is connected to the signal input terminal Vin, a second end of the third resistor R3 is connected to an anode of the third diode D3, and a cathode of the third diode D3 is connected to a first end of the second control transistor Q2.

[0062] As an example, the control module 3 further includes a third resistor R3 and a third diode D3. The first end of the second control transistor Q2, that is, the collector of the triode, is connected to the signal input terminal Vin through the third resistor R3 and the third diode D3 to obtain the collector voltage and ensure the smooth conduction of the second control transistor Q2. Specifically, the first end of the third resistor R3 is connected to the signal input terminal Vin, the second end of the third resistor R3 is connected to the anode of the third diode D3, the cathode of the third diode D3 is connected to the first end of the second control transistor Q2, the third resistor R3 functions to limit current and divide voltage, and the third diode D3 is used to prevent current backflow.

[0063] In one embodiment, the control module 3 further includes a fourth diode D4; an anode of the fourth diode D4 is connected to the reverse connection protection module 1, and a cathode of the fourth diode D4 is connected to the first end of the second control transistor Q2.

[0064] As an example, the control module 3 further includes a fourth diode D4. The anode of the fourth diode D4 is connected to the reverse connection protection module 1, and the cathode of the fourth diode D4 is connected to the first end of the second control transistor Q2. The fourth diode D4 is used to limit the current direction and prevent the current of the signal input terminal Vin from flowing into the third end of the first control transistor Q1.

[0065] An embodiment of the present invention further provides a power supply circuit, including an input interface, an electrolytic capacitor C3, and the reverse connection protection circuit in any of the above embodiments; the input interface is connected to the signal input terminal Vin of the reverse connection protection circuit, and the input interface is further used to connect to a power supply circuit; a first end of the electrolytic capacitor C3 is connected to the signal output terminal Vout of the reverse connection protection circuit, and a second end of the electrolytic capacitor C3 is grounded.

[0066] As an example, the power supply circuit includes an input interface, an electrolytic capacitor C3, and the reverse connection protection circuit in any of the above examples. The input interface is connected to the signal input terminal Vin of the reverse connection protection circuit, and the input interface is also used to connect to an external power supply circuit to receive the power supply voltage output by the power supply circuit. The power supply circuit may further include a switching power supply module. The signal output terminal Vout of the reverse connection protection circuit is connected to the switching power supply module, and is used to deliver the power supply voltage output by the power supply circuit to the switching power supply module. The switching power supply module can perform DC-DC voltage conversion on the power supply voltage and convert it into a voltage available for the subsequent load. The first end of the electrolytic capacitor C3 is connected to the connection node between the signal output terminal Vout of the reverse connection protection circuit and the switching power supply module, and is used for filtering and energy storage to make the voltage output to the power supply circuit smoother and more stable.

[0067] In this example, by adding a voltage comparison module 2 and a control module 3 to the reverse connection protection circuit in the power supply circuit, it is possible to detect in real time whether there is a voltage drop in the power supply circuit connected to the reverse connection protection circuit, and when there is a voltage drop, stop the power supply circuit from supplying power to the power supply circuit, prevent the electrolytic capacitor C3 in the power supply circuit from being repeatedly charged, extend the life of the electrolytic capacitor C3, and avoid causing a heating phenomenon.

[0068] The embodiment of the present invention further provides an automobile, including the power supply circuit in the above embodiment.

[0069] As an example, the automobile includes the power supply circuit in the above example. In this example, by adding a voltage comparison module 2 and a control module 3 to the reverse connection protection circuit in the power supply circuit, it is possible to detect in real time whether there is a voltage drop in the power supply circuit connected to the reverse connection protection circuit, and when there is a voltage drop, stop the power supply circuit from supplying power to the power supply circuit, prevent the electrolytic capacitor C3 in the power supply circuit from being repeatedly charged, extend the life of the electrolytic capacitor C3, and avoid causing a heating phenomenon.

[0070] The above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. An anti-reverse connection protection circuit, characterized in that, It includes an anti-reverse connection module, a voltage comparison module, and a control module; The anti-reverse connection module is arranged between the signal input end and the signal output end; The first end of the voltage comparison module is connected to the signal input end for obtaining a first output voltage; the second end of the voltage comparison module is connected to the signal output end for obtaining a second output voltage; the third end of the voltage comparison module is connected to the control module for outputting a control signal to the control module according to the first output voltage and the second output voltage; The control module is connected to the anti-reverse connection module for turning off or not turning off the anti-reverse connection module according to the control signal.

2. The anti-reverse connection protection circuit according to claim 1, wherein The anti-reverse connection module includes a first control tube and a drive circuit; The first end of the first control tube is connected to the signal input end, the second end of the first control tube is connected to the signal output end, and the third end of the first control tube is connected to the drive circuit; The drive circuit is connected to the signal output end and is also used to be connected to a drive chip, and controls the first control tube to conduct or turn off according to the voltage at the signal output end and the drive signal output by the drive chip; The third end of the first control tube is also connected to the control module for turning off or not turning off under the control of the control module.

3. The anti-reverse connection protection circuit according to claim 2, wherein The drive circuit includes a first capacitor, a second capacitor, a first diode, a second diode, and a voltage stabilizing tube; The first end of the first capacitor is used to be connected to the drive chip, the second end of the first capacitor is connected to the cathode of the first diode, and the anode of the first diode is connected to the signal output end; The cathode of the voltage stabilizing tube is connected to the second end of the first capacitor, the anode of the voltage stabilizing tube is connected to the anode of the second diode, and the cathode of the second diode is grounded; The first end of the second capacitor is connected to the connection node between the voltage stabilizing tube and the first capacitor, and the second end of the second capacitor is grounded; The third end of the first control tube is connected to the connection node between the voltage stabilizing tube and the first capacitor.

4. The anti-reverse connection protection circuit according to claim 3, characterized in that, The drive circuit further includes a first resistor and a second resistor; The first end of the first resistor is connected to the second end of the first capacitor, and the second end of the first resistor is connected to the cathode of the voltage stabilizing tube; The first end of the second resistor is connected to the third end of the first control tube, and the second end of the second resistor is connected to the cathode of the voltage stabilizing tube.

5. The anti-reverse connection protection circuit according to claim 1, characterized in that The voltage comparison module includes a comparator; The inverting input terminal of the comparator is connected to the connection node between the anti-reverse connection module and the signal input end; The non-inverting input terminal of the comparator is connected to the connection node between the anti-reverse connection module and the signal output end; The output terminal of the comparator is connected to the control module for outputting a first control signal to the control module when the first output voltage is less than the second output voltage, and outputting a second control signal to the control module when the first output voltage is not less than the second output voltage; The control module is used to turn off the anti-reverse connection module according to the first control signal and stop turning off the anti-reverse connection module according to the second control signal.

6. The anti-reverse connection protection circuit according to claim 1, characterized in that, The control module includes a second control transistor; The first end of the second control transistor is connected to the reverse connection prevention module, the second end of the second control transistor is connected to the voltage comparison module, and the third end of the second control transistor is grounded.

7. The anti-reverse connection protection circuit according to claim 6, wherein, The control module further includes a third resistor and a third diode; The first end of the third resistor is connected to the signal input terminal, the second end of the third resistor is connected to the anode of the third diode, and the cathode of the third diode is connected to the first end of the second control transistor.

8. The anti-reverse connection protection circuit according to claim 6, wherein The control module further includes a fourth diode; The anode of the fourth diode is connected to the reverse connection prevention module, and the cathode of the fourth diode is connected to the first end of the second control transistor.

9. A power supply circuit, characterized in that, It includes an input interface, an electrolytic capacitor, and the reverse connection prevention protection circuit according to any one of claims 1-8; The input interface is connected to the signal input terminal of the reverse connection prevention protection circuit, and the input interface is further used to connect to a power supply circuit; The first end of the electrolytic capacitor is connected to the signal output terminal of the reverse connection prevention protection circuit, and the second end of the electrolytic capacitor is grounded.

10. A vehicle, characterized in that, It includes the power supply circuit according to claim 9.

Images