Reverse connection prevention circuit

Abstract

The utility model provides a reverse connection prevention circuit, which comprises a charging unit, a switch control unit, a detection unit and a wiring unit, and is characterized in that the detection unit comprises a comparator, a first resistor connected with the comparator in parallel, and a second resistor and a third resistor connected with the first resistor in series, and a to-be-charged device, the first resistor and the second resistor form a discharging loop; as long as an electric signal exists in a to-be-charged device, level signals in different states can be output according to different voltages of the in-phase input end and the inverted input end of the comparator, and positive and negative connection judgment of the to-be-charged device and on-off control of connection between the charging unit and the wiring unit are achieved. The charging unit and the wiring unit can be disconnected under the condition that the to-be-charged device is reversely connected, the charging unit is forbidden to charge the to-be-charged device, and the to-be-charged device is prevented from being damaged. According to the scheme, the positive and negative connection judgment of the to-be-charged device and the on-off control of the charging circuit in the low-voltage state are realized, and the application range of the reverse connection prevention circuit is expanded.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of circuit design, and particularly to an anti-reverse connection circuit. Background Art

[0002] An anti-reverse connection circuit is a detection and control circuit used to detect whether a device to be charged is correctly connected to a charging line and stop charging it when the device to be charged is reversely connected, which plays an important role in protecting electronic devices.

[0003] In traditional solutions, diodes, triodes or optocouplers are usually used to design anti-reverse connection circuits, which all utilize the forward conduction and reverse cut-off characteristics of PN junctions to control the on-off of the charging line. However, a certain voltage is required for the PN junction to conduct, that is to say, this type of anti-reverse connection circuit needs to meet certain voltage conditions for the device to be charged to work properly, and its applicable range is relatively small. Utility Model Content

[0004] The embodiments of the present application provide an anti-reverse connection circuit to realize the positive and negative connection determination of a device to be charged and the on-off control of the charging line, especially in a low-voltage state, and expand the applicable range of the anti-reverse connection circuit.

[0005] In a first aspect, an anti-reverse connection circuit is provided in the embodiments of the present application, including a charging unit, a switch control unit, a detection unit and a wiring unit; the detection unit includes a comparator, a first resistor connected in parallel with the comparator, a second resistor connected in series with the first resistor, and a third resistor;

[0006] The positive output terminal of the charging unit is connected to the positive wiring terminal of the wiring unit through the switch control unit, and the negative output terminal of the charging unit is connected to the negative wiring terminal of the wiring unit and grounded; or, the positive output terminal of the charging unit is connected to the positive wiring terminal of the wiring unit, and the negative output terminal of the charging unit is connected to the negative wiring terminal of the wiring unit through the switch control unit and grounded;

[0007] The first end of the second resistor is respectively connected to the switch control unit and the positive wiring terminal of the wiring unit, the second end of the second resistor is connected in series with the first end of the first resistor, and the second end of the first resistor is connected to the negative wiring terminal of the wiring unit;

[0008] The first end of the first resistor is connected to the non-inverting input terminal of the comparator, the second end of the first resistor is connected to the inverting input terminal of the comparator, the output terminal of the comparator is connected to the first end of the third resistor and connected to the switch control unit, the second end of the third resistor is connected to the power supply; the first end or the second end of the first resistor is grounded;

[0009] When the positive electrode of the device to be charged is connected to the positive connection terminal of the connection unit and the negative electrode is connected to the negative connection terminal of the connection unit, the electrical signal in the device to be charged is transmitted to the first resistor through the second resistor. The voltage at the non-inverting input terminal of the comparator is higher than the voltage at the inverting input terminal. The comparator outputs a high-level signal to the switch control unit to control the charging unit to remain connected to the connection unit, and the charging unit charges the device to be charged.

[0010] When the positive electrode of the device to be charged is connected to the negative connection terminal of the connection unit and the negative electrode is connected to the positive connection terminal of the connection unit, the electrical signal in the device to be charged is transmitted to the second resistor through the first resistor. The voltage at the inverting input terminal of the comparator is higher than the voltage at the non-inverting input terminal. The comparator outputs a low-level signal to the switch control unit to control the charging unit to disconnect from the connection unit.

[0011] Optionally, the switch control unit includes a switch and a controller.

[0012] The positive output terminal of the charging unit is specifically connected to the positive connection terminal of the connection unit through the switch; or, the negative output terminal of the charging unit is specifically connected to the negative connection terminal of the connection unit through the switch and grounded.

[0013] The input terminal of the controller is connected to the output terminal of the comparator, and the output terminal of the controller is connected to the switch.

[0014] When the comparator outputs a high-level signal to the controller, the controller outputs a first control signal to the switch to control the switch to close, so as to control the charging unit to remain connected to the connection unit; when the comparator outputs a low-level signal to the controller, the controller outputs a second control signal to the switch to control the switch to open, so as to control the charging unit to disconnect from the connection unit.

[0015] Optionally, the switch includes a MOS transistor.

[0016] The positive output terminal of the charging unit is specifically connected to the source electrode of the P-type MOS transistor. The drain electrode of the P-type MOS transistor is connected to the positive connection terminal of the connection unit, and the gate electrode of the P-type MOS transistor is connected to the input terminal of the controller; or,

[0017] The negative output terminal of the charging unit is connected to the source electrode of the N-type MOS transistor. The drain electrode of the N-type MOS transistor is connected to the negative connection terminal of the connection unit and grounded, and the gate electrode of the N-type MOS transistor is connected to the input terminal of the controller.

[0018] Optionally, the switch includes a relay.

[0019] Optionally, the controller includes a control chip.

[0020] Optionally, the charging unit includes a charger. The positive output terminal of the charging unit includes the positive output terminal of the charger, the negative output terminal of the charging unit includes the negative output terminal of the charger, and the device to be charged includes a battery.

[0021] The reverse connection prevention circuit provided by the embodiment of the present application sets a comparator in parallel with both ends of the first resistor, and the first resistor and the second resistor are connected in series to form a detection circuit. In different situations where the device to be charged is connected in the correct or reverse direction, the voltage magnitudes at the non-inverting input terminal and the inverting input terminal of the comparator are also different. Therefore, the output terminal of the comparator can output level signals of different states. Based on the level signals of different states, it is possible to determine the correct or reverse connection of the device to be charged, and control the on / off of the connection between the charging unit and the wiring unit. When the device to be charged is connected in the reverse direction, the connection between the charging unit and the wiring unit can be disconnected, prohibiting the charging unit from charging the device to be charged, avoiding damage to the device to be charged, and the circuit structure is simple and the cost is low. Moreover, in this reverse connection prevention circuit, it can be applied to any type of device to be charged. As long as there is an electrical signal in the device to be charged, different state level signals can be output according to the different voltage magnitudes at the non-inverting input terminal and the inverting input terminal of the comparator, so as to realize the determination of the correct or reverse connection of the device to be charged and the on / off control of the connection between the charging unit and the wiring unit, solving the problem of the minimum operating voltage in the traditional solution, realizing the determination of the correct or reverse connection of the device to be charged and the on / off control of the charging line especially in the low voltage state, and expanding the applicable range of the reverse connection prevention circuit.

[0022] These aspects or other aspects of the present application will be more clearly understood in the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 FIG. shows a schematic diagram of an embodiment of a reverse connection prevention circuit provided by the present application.

[0025] Figure 2 FIG. shows a schematic diagram of another embodiment of a reverse connection prevention circuit provided by the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] In order to enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application.

[0027] In some structures described in the specification and claims of this application and the above-mentioned accompanying drawings, there are multiple structural members that appear in a specific order. The serial numbers of these structural members, such as 101, 102, etc., are only used to distinguish different structural members. It should be noted that the descriptions such as "first" and "second" in this article are used to distinguish different structural members, etc., do not represent the sequence, and do not limit that "first" and "second" are of different types.

[0028] It should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", "connection", "fixation" and other terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, which can be the communication inside two components or the interaction relationship between two components, and so on. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] The embodiments of this application can be applied to the field of circuit design, especially related to the design of reverse connection prevention circuits. A reverse connection prevention circuit is a detection and control circuit used to detect whether a device to be charged is correctly connected to a charging circuit and stop charging it when the device to be charged is reversely connected. The device to be charged is, for example, a battery, etc., and plays an important role in protecting electronic devices.

[0030] In the traditional solution, diodes, triodes or optocouplers are usually used to design the reverse connection prevention circuit, and the characteristics of forward conduction and reverse cut-off of the PN junction are used to control the on and off of the charging circuit. However, the PN junction needs a certain voltage to conduct, that is to say, this kind of reverse connection prevention circuit needs to meet a certain voltage condition of the device to be charged to work normally, and the applicable range is small. For example, when the forward voltage of a diode is 1.2V, this reverse connection prevention circuit needs the device to be charged to be higher than 1.2V to work normally. When the device to be charged is lower than 1.2V, the forward and reverse connection detection and the on and off control of the charging circuit cannot be carried out, that is, it cannot be applied to the forward and reverse connection determination of the device to be charged and the on and off control of the charging circuit under low voltage conditions.

[0031] Based on this, the inventor proposed the technical solution of this application, including a charging unit, a switch control unit, a detection unit, and a wiring unit; the detection unit includes a comparator, a first resistor connected in parallel with the comparator, a second resistor connected in series with the first resistor, and a third resistor; the positive output terminal of the charging unit is connected to the positive wiring terminal of the wiring unit through the switch control unit, and the negative output terminal of the charging unit is connected to the negative wiring terminal of the wiring unit and grounded; or, the positive output terminal of the charging unit is connected to the positive wiring terminal of the wiring unit, and the negative output terminal of the charging unit is connected to the negative wiring terminal of the wiring unit through the switch control unit and grounded; the first end of the second resistor is respectively connected to the switch control unit and the positive wiring terminal of the wiring unit, the second end of the second resistor is connected in series with the first end of the first resistor, and the second end of the first resistor is connected to the negative wiring terminal of the wiring unit; the first end of the first resistor is connected to the non-inverting input terminal of the comparator, the second end of the first resistor is connected to the inverting input terminal of the comparator, the output terminal of the comparator is connected to the first end of the third resistor and connected to the switch control unit, and the second end of the third resistor is connected to the power supply; the first end or the second end of the first resistor is grounded; when the positive electrode of the device to be charged is connected to the positive wiring terminal of the wiring unit and the negative electrode is connected to the negative wiring terminal of the wiring unit, the electrical signal in the device to be charged is transmitted to the first resistor through the second resistor, the voltage of the non-inverting input terminal of the comparator is higher than that of the inverting input terminal, and the comparator outputs a high-level signal to the switch control unit to control the charging unit and the wiring unit to remain connected, and the charging unit charges the device to be charged; when the positive electrode of the device to be charged is connected to the negative wiring terminal of the wiring unit and the negative electrode is connected to the positive wiring terminal of the wiring unit, the electrical signal in the device to be charged is transmitted to the second resistor through the first resistor, the voltage of the inverting input terminal of the comparator is higher than that of the non-inverting input terminal, and the comparator outputs a low-level signal to the switch control unit to control the charging unit and the wiring unit to disconnect.

[0032] The technical solution of this application, by setting a comparator, connecting the comparator in parallel across the first resistor, and connecting the first resistor and the second resistor in series to form a detection circuit. In different cases where the device to be charged is connected in the correct or reverse polarity, the voltage magnitudes at the non-inverting input terminal and the inverting input terminal of the comparator are also different. Therefore, the output terminal of the comparator can output level signals of different states. Based on the level signals of different states, it is possible to determine whether the device to be charged is connected in the correct or reverse polarity, and control the connection and disconnection between the charging unit and the wiring unit. It can disconnect the connection between the charging unit and the wiring unit when the device to be charged is connected in reverse polarity, prohibit the charging unit from charging the device to be charged, avoid damaging the device to be charged, and the circuit structure is simple and the cost is low. Moreover, in this reverse connection prevention circuit, it can be applied to any type of device to be charged. As long as there is an electrical signal in the device to be charged, different state level signals can be output according to the different voltage magnitudes at the non-inverting input terminal and the inverting input terminal of the comparator, so as to realize the determination of the correct or reverse connection of the device to be charged and the control of the connection and disconnection between the charging unit and the wiring unit, solve the problem of the minimum operating voltage in the traditional solution, realize the determination of the correct or reverse connection of the device to be charged especially in the low voltage state and the control of the connection and disconnection of the charging line, and expand the application scope of the reverse connection prevention circuit.

[0033] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present application.

[0034] As Figure 1 shown, it is a schematic structural diagram of an embodiment of a reverse connection prevention circuit provided by the present application, which may include a charging unit 101, a switch control unit 102, a detection unit 103, and a wiring unit 104. Among them, the detection unit 103 may include a comparator U1A, a first resistor R1 connected in parallel with the comparator U1A, a second resistor R2 connected in series with the first resistor R1, and a third resistor R3.

[0035] Among them, the positive output terminal of the charging unit 101 may be connected to the positive wiring terminal of the wiring unit 104 through the switch control unit 102, and the negative output terminal of the charging unit 101 may be connected to the negative wiring terminal of the wiring unit 104 and grounded.

[0036] Optionally, the positive output terminal of the charging unit 101 may be directly connected to the positive wiring terminal of the wiring unit 104, and the negative output terminal of the charging unit 101 may be connected to the negative wiring terminal of the wiring unit 104 through the switch control unit 102 and grounded.

[0037] The first end of the second resistor R2 can be connected to the positive wiring terminal of the switch control unit 102 and the wiring unit 104 respectively, the second end of the second resistor R2 can be connected in series with the first end of the first resistor R1, and the second end of the first resistor R1 can be connected to the negative wiring terminal of the wiring unit 104.

[0038] The first end of the first resistor R1 can be connected to the non-inverting input terminal of the comparator U1A, the second end of the first resistor R1 can be connected to the inverting input terminal of the comparator U1A, the output terminal of the comparator U1A can be connected to the first end of the third resistor R3 and connected to the switch control unit 102, and the second end of the third resistor R3 can be connected to the power supply VCC. The first end or the second end of the first resistor R1 can be grounded.

[0039] Specifically, when the positive electrode of the device to be charged is connected to the positive wiring terminal of the wiring unit 104 and the negative electrode is connected to the negative wiring terminal of the wiring unit 104, the electrical signal in the device to be charged is transmitted to the first resistor R1 through the second resistor R2. The voltage at the non-inverting input terminal of the comparator U1A is higher than the voltage at the inverting input terminal. The comparator U1A outputs a high-level signal to the switch control unit 102 to control the charging unit 101 to remain connected to the wiring unit 104, and the charging unit 101 charges the device to be charged.

[0040] When the positive electrode of the device to be charged is connected to the negative wiring terminal of the wiring unit 104 and the negative electrode is connected to the positive wiring terminal of the wiring unit 104, the electrical signal in the device to be charged is transmitted to the second resistor R2 through the first resistor R1. The voltage at the inverting input terminal of the comparator U1A is higher than the voltage at the non-inverting input terminal. The comparator U1A outputs a low-level signal to the switch control unit 102 to control the charging unit 101 to disconnect from the wiring unit 104.

[0041] In the embodiment of the present application, the detection unit adopts a detection circuit in which the first resistor and the second resistor are connected in series, and the comparator is connected in parallel across the first resistor. In this detection circuit, the second resistor and the first resistor are respectively connected to the positive wiring terminal and the negative wiring terminal of the wiring unit. When the wiring unit is connected to the device to be charged, the device to be charged can form a discharge loop with this detection circuit. In different cases where the device to be charged is connected correctly or reversely, the transmission direction of the electrical signal in the discharge loop is different, the voltage across the first resistor is different, resulting in different non-inverting input voltage and inverting input voltage of the comparator connected in parallel across the first resistor, and different level signals at the output terminal. Thus, the correct or reverse connection of the device to be charged can be determined, and further, the on-off control of the connection between the charging unit and the wiring unit can be realized through the switch control unit.

[0042] Specifically, when the device to be charged is in the correct connection situation, that is to say, when the positive electrode of the device to be charged is connected to the positive connection terminal of the wiring unit and the negative electrode is connected to the negative connection terminal of the wiring unit, the device to be charged and the detection circuit form a discharge loop. The electrical signal in the device to be charged is transmitted to the first resistor through the second resistor. At this time, there is a voltage difference across the first resistor, and the voltage at the first end of the first resistor is higher than the voltage at the second end. Correspondingly, the voltage at the non-inverting input terminal of the comparator is higher than the voltage at the inverting input terminal. Therefore, the output terminal of the comparator can output a high-level signal. This high-level signal is transmitted to the switch control unit, and the switch control unit controls to keep the charging unit and the wiring unit connected. At this time, the charging unit can charge the device to be charged through the wiring unit.

[0043] When the device to be charged is in the reverse connection situation, that is to say, when the positive electrode of the device to be charged is connected to the negative connection terminal of the wiring unit and the negative electrode is connected to the positive connection terminal of the wiring unit, the device to be charged and the detection circuit form a discharge loop. The electrical signal in the device to be charged is transmitted to the second resistor through the first resistor. At this time, there is also a voltage difference across the first resistor, and the voltage at the first end of the first resistor is lower than the voltage at the second end. Correspondingly, the voltage at the non-inverting input terminal of the comparator is lower than the voltage at the inverting input terminal. Therefore, the output terminal of the comparator can output a low-level signal. This low-level signal is transmitted to the switch control unit, and the switch control unit controls to disconnect the charging unit and the wiring unit. At this time, the charging unit cannot charge the device to be charged, avoiding damage to the device to be charged.

[0044] In the reverse connection prevention circuit provided by the embodiment of the present application, by setting a comparator, the comparator is connected in parallel across the first resistor, and the first resistor and the second resistor are connected in series to form a detection circuit. In different situations where the device to be charged is in the correct or reverse connection, the voltage magnitudes at the non-inverting input terminal and the inverting input terminal of the comparator are also different. Therefore, the output terminal of the comparator can output level signals in different states. Based on the level signals in different states, it is possible to determine whether the device to be charged is in the correct or reverse connection, and control the connection and disconnection between the charging unit and the wiring unit. It can disconnect the connection between the charging unit and the wiring unit when the device to be charged is in the reverse connection, prohibit the charging unit from charging the device to be charged, and avoid damage to the device to be charged. Moreover, the circuit structure is simple and the cost is low. And, in this reverse connection prevention circuit, it can be applied to any type of device to be charged. As long as there is an electrical signal in the device to be charged, different state level signals can be output according to the different voltage magnitudes at the non-inverting input terminal and the inverting input terminal of the comparator, so as to realize the determination of whether the device to be charged is in the correct or reverse connection and the control of the connection and disconnection between the charging unit and the wiring unit, solving the problem of the minimum operating voltage in the traditional solution, realizing the determination of whether the device to be charged is in the correct or reverse connection and the control of the connection and disconnection of the charging line especially in the low-voltage state, and expanding the application range of the reverse connection prevention circuit.

[0045] The implementation of the switch control unit will be described below.

[0046] In some embodiments, the switch control unit 102 may include a switch Q1 and a controller U2.

[0047] As Figure 1 or Figure 2 shown, the positive output terminal of the charging unit 101 may be connected to the positive wiring terminal of the wiring unit 104 via the switch Q1.

[0048] Optionally, the negative output terminal of the charging unit 101 may be connected to the negative wiring terminal of the wiring unit 104 via the switch Q1 and grounded (not shown in the figure).

[0049] The input terminal of the controller U2 may be connected to the output terminal of the comparator U1A for receiving the level signal output by the comparator U1A. The output terminal of the controller U2 may be connected to the switch Q1 for outputting a control signal to the switch Q1.

[0050] When the comparator U1A outputs a high-level signal to the controller U2, the controller U2 may output a first control signal to the switch Q1 to control the switch Q1 to close, so as to control the charging unit 101 and the wiring unit 104 to remain connected; when the comparator U1A outputs a low-level signal to the controller U2, the controller U2 may output a second control signal to the switch Q1 to control the switch Q1 to open, so as to control the charging unit 101 and the wiring unit 104 to disconnect.

[0051] In this embodiment, the switch control unit may be composed of two parts: a switch and a controller. The switch may be arranged on the line connecting the charging unit and the wiring unit, on the line between the positive output terminal of the charging unit and the positive wiring terminal of the wiring unit, or on the line between the negative output terminal of the charging unit and the negative wiring terminal of the wiring unit. Of course, switches may also be arranged on both lines. This application does not limit this.

[0052] The controller may be respectively connected to the output terminals of the switch and the comparator, receive the level signals of the output terminals, and output corresponding control signals to the switch to control the closing or opening of the switch. Among them, the first control signal is different from the second control signal.

[0053] By setting a switch on the line connecting the charging unit and the wiring unit, and a controller connected to the output terminals of the switch and the comparator respectively, different voltage signals across the two ends of the first resistor in the discharge circuit when the device to be charged is connected in reverse or forward are converted into different level signals at the output terminal of the comparator, and further the different level signals are converted into different control signals to control the closing or opening of the switch, so as to realize the on-off control of the connection between the charging unit and the wiring unit, and prevent the charging unit from charging the device to be charged when the device to be charged is connected in reverse, thus avoiding damage to the device to be charged.

[0054] In some embodiments, the above switch may include a MOS transistor.

[0055] Specifically, when the switch is disposed on the line between the positive output terminal of the charging unit and the positive wiring terminal of the wiring unit, the MOS transistor can be implemented as a P-channel MOS transistor. As Figure 1 or Figure 2 shown, the positive output terminal of the charging unit 101 may be connected to the source of the P-type MOS transistor, the drain of the P-type MOS transistor may be connected to the positive wiring terminal of the wiring unit 104, and the gate of the P-type MOS transistor may be connected to the input terminal of the controller U2.

[0056] Optionally, when the switch is disposed on the line between the negative output terminal of the charging unit and the negative wiring terminal of the wiring unit, the MOS transistor can be implemented as an N-channel MOS transistor. Specifically, the negative output terminal of the charging unit may be connected to the source of the N-type MOS transistor, the drain of the N-type MOS transistor may be connected to the negative connection terminal of the wiring unit and grounded, and the gate of the N-type MOS transistor may be connected to the input terminal of the controller (not shown in the figure).

[0057] Among them, the MOS transistor (Metal Oxide Semiconductor Field Effect Transistor, also known as insulated gate field effect transistor) has the advantages of high input impedance, small driving power, fast switching speed, etc., and is widely used in switching circuits.

[0058] In this embodiment, when the switch is implemented as a P-channel MOS transistor, the first control signal output by the controller may be a high-level signal, such that Vgs (gate-source voltage) is less than the threshold value, and the P-channel MOS transistor is turned on, realizing the closing of the switch and controlling the charging unit and the wiring unit to remain connected; the second control signal may be a low-level signal, such that Vgs is greater than the threshold value, and the P-channel MOS transistor is not turned on, realizing the opening of the switch and controlling the charging unit and the wiring unit to be disconnected.

[0059] Optionally, when the switch is implemented as an N-channel MOS transistor, a corresponding high-level or low-level signal can be output based on the Vgs threshold of the N-channel MOS transistor as a control signal to control the conduction or cutoff of the N-channel MOS transistor, which will not be elaborated herein.

[0060] In some embodiments, the above-mentioned switch can also be implemented as a relay.

[0061] Among them, the relay has the advantages of strong stability, long service life, strong switching ability, etc., and can be widely used in switching circuits.

[0062] In some embodiments, the controller can be implemented as a control chip.

[0063] Among them, the control chip (Microcontroller Unit, abbreviated as MCU, also known as the microcontroller unit) has the advantages of high integration, small size, low power consumption, low cost, fast processing speed, etc., and can achieve real-time control, and is widely used in circuits with fast response, low power consumption, etc.

[0064] In some embodiments, the charging unit includes a charger.

[0065] Among them, the positive output terminal of the charging unit can include the positive output terminal of the charger, the negative output terminal of the charging unit can include the negative output terminal of the charger, and the device to be charged can include a battery. The type of the battery is not limited in this application and can be applicable to any type of battery, expanding the applicable range of the reverse connection prevention circuit.

[0066] Those skilled in the art can clearly understand that the above-described device embodiments are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application 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 for some of the technical features. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A reverse connection protection circuit, characterized in that: It includes a charging unit, a switch control unit, a detection unit and a wiring unit; the detection unit includes a comparator, a first resistor connected in parallel with the comparator, a second resistor connected in series with the first resistor, and a third resistor; The positive output terminal of the charging unit is connected to the positive terminal of the wiring unit via the switch control unit, and the negative output terminal of the charging unit is connected to the negative terminal of the wiring unit and grounded; or, the positive output terminal of the charging unit is connected to the positive terminal of the wiring unit, and the negative output terminal of the charging unit is connected to the negative terminal of the wiring unit via the switch control unit and grounded; The first end of the second resistor is connected to the positive wiring terminal of the switch control unit and the wiring unit respectively, the second end of the second resistor is connected in series with the first end of the first resistor, and the second end of the first resistor is connected to the negative wiring terminal of the wiring unit; The first end of the first resistor is connected to the non-inverting input end of the comparator, the second end of the first resistor is connected to the inverting input end of the comparator, the output end of the comparator is connected to the first end of the third resistor and is connected to the switch control unit, the second end of the third resistor is connected to the power supply; the first end or the second end of the first resistor is grounded; When the positive electrode of the device to be charged is connected to the positive terminal of the wiring unit, and the negative electrode is connected to the negative terminal of the wiring unit, the electrical signal in the device to be charged is transmitted to the first resistor via the second resistor, the voltage at the non-inverting input terminal of the comparator is higher than the voltage at the inverting input terminal, and the comparator outputs a high-level signal to the switch control unit to control the charging unit to maintain connection with the wiring unit, so that the charging unit charges the device to be charged; When the positive electrode of the device to be charged is connected to the negative terminal of the wiring unit, and the negative electrode is connected to the positive terminal of the wiring unit, the electrical signal in the device to be charged is transmitted to the second resistor via the first resistor, the voltage at the reverse input terminal of the comparator is higher than the voltage at the in-phase input terminal, and the comparator outputs a low-level signal to the switch control unit to control the charging unit to disconnect from the wiring unit.

2. The circuit according to claim 1, characterized in that The switch control unit includes a switch and a controller; The positive output terminal of the charging unit is specifically connected to the positive terminal of the wiring unit via the switch; or the negative output terminal of the charging unit is specifically connected to the negative terminal of the wiring unit via the switch and grounded; The input end of the controller is connected to the output end of the comparator, and the output end of the controller is connected to the switch; When the comparator outputs a high-level signal to the controller, the controller outputs a first control signal to the switch to control the switch to close, so as to control the charging unit to remain connected to the wiring unit; when the comparator outputs a low-level signal to the controller, the controller outputs a second control signal to the switch to control the switch to open, so as to control the charging unit to be disconnected from the wiring unit.

3. The circuit according to claim 2, characterized in that The switch comprises a MOS tube; The positive output terminal of the charging unit is specifically connected to the source of the P-type MOS tube, the drain of the P-type MOS tube is connected to the positive terminal of the wiring unit, and the gate of the P-type MOS tube is connected to the input terminal of the controller; or, The negative output end of the charging unit is connected to the source of the N-type MOS tube, the drain of the N-type MOS tube is connected to the negative connection end of the wiring unit and grounded, and the gate of the N-type MOS tube is connected to the input end of the controller.

4. The circuit according to claim 2, characterized in that The switch includes a relay.

5. The circuit according to claim 2, characterized in that The controller includes a control chip.

6. The circuit according to claim 1, characterized in that The charging unit includes a charger, the positive output end of the charging unit includes the positive output end of the charger, the negative output end of the charging unit includes the negative output end of the charger, and the device to be charged includes a battery.

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