CN116316517A - Low-energy-consumption power supply reverse connection prevention protection circuit with indication function in wide voltage range - Google Patents

Abstract

The invention provides a low-energy consumption power supply reverse connection preventing protection circuit with an indication function in a wide voltage range, which comprises an external power supply interface circuit, a reverse connection preventing protection circuit and a load interface circuit which are connected in sequence; the reverse connection preventing protection circuit comprises an A-path circuit and a B-path circuit; one ends of the A circuit and the B circuit are respectively connected with the external power supply interface circuit, the other ends of the A circuit and the B circuit are respectively correspondingly connected with the load interface circuit, and reverse connection preventing modules are arranged on the A circuit and the B circuit; the reverse connection preventing module is respectively connected to the A-circuit and the B-circuit. The problem of need frequently change, maintenance difficulty that exist in traditional protective tube scheme has been solved to this application, very big simplification maintenance and troubleshooting's work load, has promoted test efficiency.

Description

Low-energy-consumption power supply reverse connection prevention protection circuit with indication function in wide voltage range

Technical Field

The invention relates to the technical field of power electronics, in particular to a low-energy-consumption power supply reverse connection prevention protection circuit with indication in a wide voltage range.

Background

In the field of power electronics, as an important power source of equipment, a power supply is an indispensable device, the use frequency is very high in the development and test process of electric equipment and products, frequent connection and dismantling of power supply wiring are indispensable, in the process, wiring errors or reverse plug insertion are unavoidable, in the electric equipment, due to the characteristics of a power supply loop, the wiring of the positive electrode and the negative electrode of the power supply is always the same in wire diameter and specification, the probability of confusion and errors is definitely increased, and investigation wiring is always greatly influenced by personnel subjectively through means such as drawing, personnel visual inspection and the like, and reliability is not guaranteed. Once the anode and the cathode of the equipment are connected and reversely electrified, the internal important devices or chips of the equipment are often burnt, irreversible damage and even casualties are caused to the equipment. This undoubtedly reduces development efficiency and increases costs.

The traditional reverse connection prevention circuit often adopts a blocking method for the reverse connection problem of the circuit, namely, a certain means (such as designing a certain device or a circuit) is adopted, so that the circuit is not conducted in a reverse connection state, and a power supply and a later-stage system are in a disconnection state, thereby achieving the purpose of protecting the circuit. The method is based on the anti-reverse design of a diode, a fuse or a MOS tube, but the methods have different defects, in particular: the diode anti-reflection circuit has the problem of pipe voltage drop, and is characterized by large heating value and low efficiency in high-current application; the fuse scheme has the problems of frequent replacement and difficult maintenance; the scheme of connecting MOS tubes in series has the problem of high MOS drive voltage, and in low-voltage application, the problem of high loss caused by high internal resistance of the MOS tubes is reflected. In addition, the three conventional reverse connection prevention schemes have the problems that after reverse connection and power-on, a circuit cannot be automatically corrected and can only be manually checked and maintained, and the maintenance and the troubleshooting are very inconvenient in high-altitude equipment and equipment with a shell.

Disclosure of Invention

In view of this, this application provides a low energy consumption power supply anti-reverse connection protection circuit of wide voltage range area instruction for solve among the above-mentioned prior art reverse connection after the power on, the unable self-correction's of circuit problem, specific scheme is:

the low-energy-consumption power supply reverse connection preventing protection circuit with the indication in the wide voltage range comprises an external power supply interface circuit, a reverse connection preventing protection circuit and a load interface circuit which are connected in sequence;

the reverse connection preventing protection circuit comprises an A circuit and a B circuit, wherein the A circuit and the B circuit form a main loop and are used for realizing the communication between an external power supply interface circuit and a load interface circuit;

one ends of the A-way circuit and the B-way circuit are respectively connected with the external power supply interface circuit, the other ends of the A-way circuit and the B-way circuit are respectively correspondingly connected with the load interface circuit, and reverse connection preventing modules are arranged on the A-way circuit and the B-way circuit;

the reverse connection preventing module is respectively connected to the circuit A and the circuit B.

Preferably, the reverse connection preventing module comprises a relay K1 with a built-in double-pole double-throw switch;

two ends of the relay K1 are respectively connected to the circuit A and the circuit B, and a primary coil of the relay K1 controls a double-pole double-throw switch serving as a secondary side of the relay K1;

two common ends of the double-pole double-throw switch are respectively and fixedly connected to the A-circuit and the B-circuit, and a normally closed end NC and a normally open end NO of the double-pole double-throw switch are respectively connected with the load interface circuit;

the normally closed end NC comprises an output end 1A and an output end 2A, and the normally open end NO comprises an output end 1B and an output end 2B;

the output end 1A and the output end 1B are used as two output ends of one double-throw switch of the double-pole double-throw switches, and the output end 2A and the output end 2B are used as two output ends of the other double-throw switch of the double-pole double-throw switches; the output end 1A and the output end 2B are short-circuited and then commonly connected to the positive electrode of the load interface circuit; the output end 2A is short-circuited with the output end 1B, and then the negative electrodes of the load interface circuits are commonly connected.

Preferably, a circuit in which the primary coil of the relay K1 is positioned is provided with an anti-reverse connection indicating circuit;

the reverse connection preventing indication circuit is connected with the primary coil of the relay K1 in series.

Preferably, the reverse connection preventing indication circuit comprises a first current limiting resistor R1 and a first indication element;

the input end of the first current limiting resistor R1 is connected to the circuit B, and the first current limiting resistor R1 is connected in series with the first indicating element;

the output end of the first indicating element is connected with the input end of the primary coil of the relay K1;

and the output end of the primary coil of the relay K1 is connected to the A-circuit.

Preferably, when the external power supply has smaller power, the first indicating element is an LED1.

Preferably, when the external power supply has high power, the first indicating element is a diode.

Preferably, the load interface circuit includes a positive terminal v+ and a negative terminal V-;

the positive electrode terminal V+ and the negative electrode terminal V-are respectively connected with a post-stage circuit;

the output ends of the anti-reverse connection protection circuit are respectively connected with the positive electrode terminal V+ and the negative electrode terminal V-.

Preferably, a system power-on indication circuit is arranged on the load interface circuit;

the two ends of the system power-on indicating circuit are respectively connected with the positive terminal V+ and the negative terminal V-.

Preferably, the system power-on indication circuit comprises a second current limiting resistor R2 and a second indication element LED2;

the input end of the second current limiting resistor is connected with the positive electrode terminal V+, and the second current limiting resistor R2 and the second indicating element LED2 are connected in series;

the output of the second indicator element LED2 is connected to the negative terminal V.

Preferably, the external power supply interface circuit comprises an A end and a B end respectively;

the A-path circuit and the B-path circuit are respectively connected with the A end and the B end.

Compared with the prior art, the beneficial effect of this application lies in:

in the method, a primary side control coil and a secondary side double-pole double-throw switch are arranged in a main loop, namely an A-path circuit and a B-path circuit to realize a conduction function, and as no diode and other devices causing voltage drop exist in a main power loop, the method solves the problem that the efficiency is greatly affected by large-current application heating value due to pipe voltage drop in the traditional diode anti-reflection circuit;

the circuit in the application has no fuse type vulnerable part, so that the problems of frequent replacement and difficult maintenance in the traditional fuse scheme are solved;

according to the MOS transistor driving circuit, a MOS transistor driving circuit is not required to be built, and the problems that in a scheme of connecting MOS transistors in series, the MOS driving voltage requirement is high (the internal resistance of the MOS transistor is small in a complete conduction state, but the complete conduction voltage VGS of PMOS is often at a negative 4.5V or even higher value, which can not be obviously achieved in low-voltage application) and the internal resistance and the loss of the MOS transistor are large in low-voltage application are solved, so that the low-voltage application is limited;

meanwhile, the invention solves the problems that the circuit cannot be automatically corrected and can only be manually inspected and maintained after the reverse connection is electrified in the three conventional reverse connection prevention schemes, and particularly in the application of high-altitude equipment and equipment with a shell, the workload of maintenance and troubleshooting is greatly simplified, and the test efficiency is improved;

the reverse connection prevention indicating circuit and the system power-on indicating circuit are arranged, so that the system can be visual under the condition of no instrumentKnowledge ofThe wiring state of the circuit is convenient for field operation.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate the invention and together with the embodiments of the invention, serve to explain the invention.

In the drawings:

FIG. 1 is a block diagram of a low power consumption anti-reverse protection circuit with indication in a wide voltage range according to the present invention;

FIG. 2 is a schematic circuit diagram of a low power consumption anti-reverse connection protection circuit with indication in a wide voltage range in an embodiment of the invention when the external power supply is low;

FIG. 3 is a schematic diagram of a current path in a system forward state in an embodiment of a low power consumption power supply anti-reverse connection protection circuit with indication in a wide voltage range according to the present invention;

FIG. 4 is a schematic diagram of a current path in a reverse system connection state in an embodiment of a low power consumption power supply reverse connection protection circuit with indication in a wide voltage range according to the present invention;

FIG. 5 is a schematic circuit diagram of a low power consumption anti-reverse connection protection circuit with indication in a wide voltage range in an embodiment of the invention when the external power supply has a larger power;

FIG. 6 is a schematic diagram of a diode-based anti-reverse connection circuit of the prior art;

FIG. 7 is a schematic diagram of a prior art reverse connection prevention based on a protective tube;

FIG. 8 is a schematic diagram of a prior art MOS anti-reverse circuit;

the system comprises a power supply module, an external power supply interface circuit, a reverse connection preventing protection circuit, a load interface circuit, a reverse connection preventing indication circuit, a system power-on indication circuit and a reverse connection preventing module, wherein the power supply module comprises a power supply interface circuit, a reverse connection preventing protection circuit, a load interface circuit, a reverse connection preventing indication circuit, a power-on indication circuit and a reverse connection preventing module.

Detailed Description

The preferred embodiments of the present invention will be described below with reference to the accompanying drawings, it being understood that the preferred embodiments described herein are for illustration and explanation of the present invention only, and are not intended to limit the present invention.

The low-energy-consumption power supply reverse connection preventing protection circuit with indication according to the wide voltage range shown in the figures 1-5 comprises an external power supply interface circuit 101, a reverse connection preventing protection circuit 102 and a load interface circuit 103 which are connected in sequence;

the reverse connection preventing protection circuit 102 comprises an A-way circuit and a B-way circuit, wherein the A-way circuit and the B-way circuit form a main loop, and are used for realizing the communication between the external power supply interface circuit 101 and the load interface circuit 103;

one ends of the A-way circuit and the B-way circuit are respectively connected with the external power supply interface circuit 101, the other ends of the A-way circuit and the B-way circuit are respectively correspondingly connected with the load interface circuit 103, and the A-way circuit and the B-way circuit are provided with an anti-reverse connection module 106;

the anti-reverse connection module 106 is connected to the circuit a and the circuit B, respectively.

Further, the reverse connection preventing module 106 includes a relay K1 with a built-in double pole double throw switch;

two ends of the relay K1 are respectively connected to the circuit A and the circuit B, and a primary coil of the relay K1 controls a double-pole double-throw switch serving as a secondary side of the relay K1;

two common ends of the double-pole double-throw switch are respectively and fixedly connected to the A-circuit and the B-circuit, and a normally closed end NC and a normally open end NO of the double-pole double-throw switch are respectively connected with the load interface circuit 103;

the normally closed end NC comprises an output end 1A and an output end 2A, and the normally open end NO comprises an output end 1B and an output end 2B;

the output end 1A and the output end 1B are used as two output ends of one of the double-pole double-throw switches, and the output end 2A and the output end 2B are used as two output ends of the other of the double-pole double-throw switches; the output end 1A and the output end 2B are short-circuited and then commonly connected to the positive electrode of the load interface circuit 103; the output terminal 2A is short-circuited with the output terminal 1B, and then commonly connected to the negative electrode of the load interface circuit 103.

Further, a circuit where the primary coil of the relay K1 is located is provided with an anti-reverse connection indicating circuit 104;

the reverse connection preventing indication circuit 104 is connected in series with the primary coil of the relay K1.

Further, the anti-reverse connection indicating circuit 104 includes a first current limiting resistor R1 and a first indicating element;

the input end of the first current limiting resistor R1 is connected to the circuit B, and the first current limiting resistor R1 is connected in series with the first indicating element;

the output end of the first indicating element is connected with the input end of the primary coil of the relay K1;

and the output end of the primary coil of the relay K1 is connected to the A-circuit.

Further, when the external power supply has smaller power, the first indicating element is the LED1.

Further, when the external power supply has larger power, the first indicating element is a diode.

Further, the load interface circuit 103 includes a positive terminal v+ and a negative terminal V-;

the positive electrode terminal V+ and the negative electrode terminal V-are respectively connected with a post-stage circuit;

the output terminals of the anti-reverse connection protection circuit 102 are connected to the positive terminal v+ and the negative terminal V-, respectively.

Further, a system power-on indication circuit 105 is arranged on the load interface circuit 103;

the system power-on indication circuit 105, two ends of the system power-on indication circuit 105 are respectively connected with the positive terminal V+ and the negative terminal V- (ground).

Further, the system power-on indication circuit 105 includes a second current limiting resistor R2 and a second indication element LED2;

the input end of the second current limiting resistor is connected to the positive electrode terminal V+, and the second current limiting resistor R2 is connected in series with the second indicating element LED2;

the output end of the second indicating element LED2 is grounded.

It should be noted that:

as shown in fig. 2, the whole circuit system of the low-energy-consumption power supply reverse connection prevention protection circuit with indication in a wide voltage range of the invention comprises: an external power supply interface circuit 101 connected with an external power supply, a reverse connection preventing protection circuit 102 having a reverse connection preventing protection function for a starting circuit, and a load interface circuit 103 for connecting a load circuit of a subsequent stage of the system,

in one embodiment of the present application, the external power supply interface circuit 101 is a connection plug, where the anode and the cathode of the connection plug are fixedly arranged, that is, an end a and an end B, where the end a and the end B are connected to an external dc power supply through an incoming line, respectively, and meanwhile, the end a and the end B are connected to an anode terminal v+ and a cathode terminal V "of the load interface circuit 103 through an a circuit and a B circuit, respectively, where the B circuit is grounded;

in the application, the reverse connection preventing protection circuit 102 mainly comprises a relay K1 serving as a primary coil and a double-pole double-throw switch serving as a secondary, wherein the primary coil of the relay K1 controls the double-pole double-throw switch serving as the secondary, two input ends of the double-pole double-throw switch are respectively connected to an A-path circuit and a B-path circuit, and two output ends (1A end, 2A end, 1B end and 2B end) of the same single-pole switch in four output ends (1A end and 1B end) of the double-pole double-throw switch are respectively connected to a positive electrode terminal V+ and a negative electrode terminal V-of the load interface circuit 103;

wherein the 1A end and the 2A end are normally closed ends NC, the 1B end and the 2B end are normally open ends NO, the 1A in the normally closed ends NC of the switch S1 and the 2B in the normally open ends NO of the switch S2 in the double pole double throw switch are short-circuited, then are connected to the positive terminal V+ together, and the 1B in the normally open ends NO of the switch S1 and the 2A in the normally closed ends NC of the switch S2 are short-circuited and then are connected to the negative terminal V-,

in one embodiment of the present application, the primary coil and the secondary double-pole double-throw switch of the relay K1 are packaged in a component, 8 pipe pins are arranged on the packaged component, the positions of the 8 pipe pins are shown as numerals 1-8 in fig. 2, the pipe pins 1 and 8 are respectively positioned at the input end and the output end of the primary coil of the relay K1, the pipe pins 3 and 6 are respectively positioned at two input ends (common ends) of the double-pole double-throw switch, and the pipe pins 2 and 4 and the pipe pins 5 and 7 are respectively positioned at four output ends of the double-pole double-throw switch;

in order to prompt and prevent reverse connection during reverse connection, a reverse connection prevention indicating circuit 104 is arranged between the relay K1 and the B-path circuit, namely, a first current limiting resistor R1 and a first indicating element are respectively connected in series between the relay K1 and the B-path circuit, wherein the first indicating element is positioned between the first current limiting resistor R1 and the relay K1, the first indicating element is used for indicating during reverse connection, the first current limiting resistor R1 acts as a current limiting, safety is actually considered, and two diodes are generally connected in reverse parallel at two ends of the relay K1.

In one embodiment of the present application, it is contemplated that a separate diode (e.g., schottky diode) may be used for anti-reflection when the external power source is a high power source, as shown in fig. 5; when the external power supply is a low-power supply, the LED1 is used as a first indicating element, when the primary coil of the relay K1 is electrified, the LED1 is lightened, and meanwhile, the armatures of the switch S1 and the switch S2 are switched to the 1B end and the 2B end in the normally open end NO under the action of stress. When the primary coil of the relay K1 is powered off, the switch S1 and the switch S2 are switched back to the normally closed ends NC 1A and 2A;

the load interface circuit 103 mainly comprises a positive wiring terminal V+ and a negative wiring terminal V-which are respectively connected with a subsequent circuit;

in order to understand the system power-on state, a system power-on indication circuit 105 is additionally added on the load interface circuit 103, the system power-on indication circuit 105 comprises a second current limiting component R2 and a second indication element LED2, wherein the second current limiting resistor R2 is positioned between the second indication element LED and the positive terminal V+, the second current limiting resistor R2 is used for limiting the current of the LED2, and for the circuit, no matter the external power supply interface 101 is connected in a positive-negative way, the LED2 is lightened, so that the system is always ensured to be in a correct wiring.

In this application, in order to distinguish between the first indicating element and the second element, the first indicating element is provided as a yellow-light emitting electronic element, and the second indicating element is provided as a green-light emitting electronic element.

The specific principle of the circuit operation of the application is described as follows:

in the positive connection state of the circuit (positive connection state is assumed when the end A is positive and negative end B is positive in the embodiment, otherwise, the current path is shown in fig. 3, at this time, the circuit A is connected with the positive terminal V+ of the load interface circuit, the circuit B is connected with the negative terminal V-of the load interface circuit, at this time, the circuit A is connected with the cathode of the first indicating element LED1 through the primary coil of the relay K1, the circuit B is connected with the anode of the first indicating element LED1 through the first current limiting resistor R1, the PN junction is reversely biased, the first indicating element LED1 (yellow LED is selected here) is reversely cut off, and the primary coil of the relay K1 is in the extinction state, so that the primary coil of the relay K1 cannot be electrified; the common ends of the two switches S1 and S2 serving as the secondary sides are respectively connected with the 1A end and the 2A end in the corresponding normally closed end NC, namely, as shown in fig. 3, the tube pin 6 of the relay K1 is connected with 7, the tube pin 3 is connected with 2, the positive electrode of an external power supply is connected with the A end of the connector J1, the positive electrode terminal V+ of the load interface circuit 103 is connected with the positive electrode terminal V+ of the load interface circuit 103 through the S1, the negative electrode terminal V-of the load interface circuit 103 is connected with the B end of the connector J1 through the switch S2, and the negative electrode of the external power supply is returned to form a loop.

A second indicator element LED2 in the system power-on indicator circuit 105 is lighted, wherein the LED2 is selected to be green, and a green light is lighted to represent that the system is normally powered on to work;

fig. 4 shows a schematic diagram of a current path in a reverse connection state of the system, where the connector J1 is in the reverse connection state, the connector J1 a is connected to a negative pole of an external power source, and the connector B is connected to a negative pole of the external power source. At this time, the circuit A is connected with the cathode of the LED1 through the primary coil, the circuit B is connected with the anode of the LED1 through the first current limiting resistor R1, the circuit A is negative, the circuit B is positive, the PN junction is forward biased, the diode LED1 is conducted, the yellow lamp LED1 is lighted, the primary coil of the relay K1 is conducted, the LED1 can be replaced by a Schottky diode, the energy consumption can be further reduced, and the defect that the LED1 loses the reverse connection indication function is overcome. Under the electromagnetic force of the primary coil, the switch S1 and the switch S2 are attracted to 1B and 2B in the normally open ends NO of the armature; the common terminal is respectively connected with 1B and 2B, namely as shown in FIG. 4, the tube pin 6 of the relay K1 is connected with 5, and the tube pin 3 is connected with 4, so that the switching of the switch state is completed. At this time, the positive electrode B circuit is connected with the positive electrode terminal V+ of the load circuit 103 through the 2B of the switch S2, and the negative electrode terminal V-of the load circuit 103 is connected with the positive electrode B through the 1B of the switch S1; the second indicator element LED2 (green) in the system power-on indicator circuit 105 lights up normally and the green lights up, representing normal operation of the system, and as can be seen from process analysis, the circuit can still operate normally in the reverse state.

According to the analysis of the positive and negative states of the system, the positive and negative terminals V+ of the positive terminal V+ of the external power supply can be kept to be connected with the positive electrode of the external power supply, the negative terminal V-of the external power supply can be kept to be connected with the negative electrode of the external power supply, the indicator lamps of the second indicator element LED2 can be normally turned on, and the system power-on indicator circuit 105 can normally work. That is, for wiring and testers, one wiring can be ensured to be correct without worrying about miswiring.

In addition, the reverse connection prevention indication circuit 104 realizes that the circuit has a positive and negative state wiring indication function, so that the current wiring state can be clearly known, and when the circuit is in the positive connection state (namely, the circuit A is positive, the circuit B is negative), only the green light of the second indication element LED2 is turned on, the yellow light of the first indication element LED1 is turned off, and the circuit is in the positive connection state; when the lines are reversely connected (the circuit A is negative, the circuit B is positive), the green light of the second indicator element LED2 and the yellow light of the first indicator element LED1 are both lighted, and the marking system line is in a reversely connected state.

As shown in figure 6, the scheme utilizes the unidirectional conductive characteristic of the diode to connect the diode in series at the power inlet to achieve the purpose of circuit anti-reflection, the circuit is simple and reliable, and the application range is very wide, however, the main problem of the anti-reflection circuit is the loss problem, because the PN junction of the diode has about 0.7V voltage drop, the diode is always connected in series in the circuit to participate in power consumption in the whole device electrifying process, which is particularly unfavorable in the application of large current, and has the problems of large heat productivity and low circuit efficiency.

Fig. 7 is a schematic diagram of a reverse connection preventing scheme of a fuse tube in the prior art, and the fuse tube is connected in series in a circuit (generally used together with an anti-parallel diode connected across the positive and negative electrodes of a power supply), so that when the circuit is connected reversely, the fuse tube can be burned out due to overcurrent, thereby protecting a later-stage circuit from damage. However, each time of error connection, one insurance needs to be replaced, and maintenance is troublesome;

fig. 8 is a schematic diagram of the prior art for preventing reverse connection by using a MOS transistor (usually PMOS: P-channel MOSFET) connected in series at the power supply inlet, and the PMOS transistor is turned on by the negative pressure generated between the circuit GSs when the circuit is being connected. In the reverse connection, the PMOS does not meet the conduction condition due to the positive voltage between the GSs. Thereby cutting off the connection between the power supply and the rear stage and achieving the purpose of reverse connection prevention. Since the on-resistance of the MOS transistor is only a few tens milliohms (even lower) under the action of the appropriate gate-source drive voltage VGS, the voltage drop in the power loop is almost negligible. The power consumption of the anti-reverse circuit power loop is greatly reduced, and the circuit is improved to a certain extent compared with the former two schemes. The following problems still remain: 1. the circuit can not be automatically adjusted to a correct state after reverse connection, and the equipment can continue to power on after the line is changed manually. This is particularly inconvenient in some high-altitude devices, or devices with housings, which often require the device to be assembled in place before the switch can be turned on. And once the power-on is connected reversely, people are required to climb to the equipment to detach, and the wiring points are found to correct, so that the equipment is very inconvenient. In the fully on state of the mos transistor, the internal resistance is small (on the order of tens of milliohms), but the fully on voltage VGS of the PMOS tends to be negative 4.5V or even higher (voltage absolute value), which is clearly not achievable in low voltage applications. For example, in the anti-reverse circuit of the unit cell, the battery voltage is 2V or less. Obviously, the PMOS cannot be completely turned on at this time, and the internal resistance is quite large at this time, so that the loss generated by the voltage drop of the tube is not negligible, which can seriously affect the circuit efficiency and even affect the normal operation of the circuit.

The device causing voltage drop such as a diode is not arranged in the main power loop, so that the application of the device in the field of high current is realized, and the problem of heat generation is not required to influence the circuit efficiency; the defects of large heat and high loss of the traditional diode anti-reflection circuit in a large-current application environment are overcome;

the invention solves the problem that the MOS is driven to be conducted by a higher voltage in the anti-reverse circuit using the MOS tube in the prior art, and can be adapted in a wider voltage range.

The invention is especially suitable for the equipment testing stage, and the scene of frequently connecting and dismantling the power supply wiring is required, so that personnel errors can be effectively avoided, and the testing efficiency is improved.

In the present application, the switching circuit for switching functions is not limited to a mechanical switch, and includes electronic components functioning as a switch, such as a transistor, a MOSFET, and an analog switch, and other components for realizing the switching functions of an electrical switch.

In the present application, NO is normally OPEN (NORMAL OPEN), i.e., is normally OPEN when not energized, and is closed when energized by the electromagnetic coil (attraction).

In this application, NC is normally CLOSED (NORMAL CLOSED), that is, CLOSED in a NORMAL, i.e., non-energized state, and is opened by the electromagnetic coil after being energized.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims (10)

1. The low-energy-consumption power supply reverse connection prevention protection circuit with the indication function in the wide voltage range is characterized by comprising an external power supply interface circuit (101), a reverse connection prevention protection circuit (102) and a load interface circuit (103) which are connected in sequence;

the anti-reverse connection protection circuit (102) comprises an A-way circuit and a B-way circuit, wherein the A-way circuit and the B-way circuit form a main loop and are used for realizing the communication between an external power supply interface circuit (101) and a load interface circuit (103);

one ends of the A-way circuit and the B-way circuit are respectively connected with the external power supply interface circuit (101), the other ends of the A-way circuit and the B-way circuit are respectively correspondingly connected with the load interface circuit (103), and the A-way circuit and the B-way circuit are provided with an anti-reverse connection module (106);

the reverse connection preventing module (106) is respectively connected to the A-circuit and the B-circuit.

2. The low-energy power supply reverse connection prevention protection circuit with indication of the wide voltage range according to claim 1, wherein the reverse connection prevention module (106) comprises a relay K1 with a built-in double-pole double-throw switch;

two ends of the relay K1 are respectively connected to the circuit A and the circuit B, and a primary coil of the relay K1 controls a double-pole double-throw switch serving as a secondary side of the relay K1;

two common ends of the double-pole double-throw switch are respectively and fixedly connected to the A-circuit and the B-circuit, and a normally closed end NC and a normally open end NO of the double-pole double-throw switch are respectively connected with the load interface circuit (103);

the normally closed end NC comprises an output end 1A and an output end 2A, and the normally open end NO comprises an output end 1B and an output end 2B;

the output end 1A and the output end 1B are used as two output ends of one of the double-pole double-throw switches, and the output end 2A and the output end 2B are used as two output ends of the other of the double-pole double-throw switches; the output end 1A and the output end 2B are short-circuited and then commonly connected to the positive electrode of the load interface circuit (103); the output end 2A is short-circuited with the output end 1B, and then the negative electrode of the load interface circuit (103) is commonly connected.

3. The low-energy-consumption power supply reverse connection prevention protection circuit with indication in a wide voltage range according to claim 2, wherein a reverse connection prevention indication circuit (104) is arranged on a circuit where a primary coil of the relay K1 is positioned;

the reverse connection prevention indicating circuit (104) is connected with the primary coil of the relay K1 in series.

4. A low power supply anti-reverse connection protection circuit with indication according to claim 3, characterized in that said anti-reverse connection indication circuit (104) comprises a first current limiting resistor R1 and a first indication element;

the input end of the first current limiting resistor R1 is connected to the circuit B, and the first current limiting resistor R1 is connected in series with the first indicating element;

the output end of the first indicating element is connected with the input end of the primary coil of the relay K1;

and the output end of the primary coil of the relay K1 is connected to the A-circuit.

5. The low power consumption power supply reverse connection preventing protection circuit with indication according to claim 4, wherein the first indication element is an LED1 when the external power supply has a smaller power.

6. The low power consumption power supply reverse connection preventing protection circuit with indication according to claim 4, wherein the first indication element is a diode when the external power supply has a large power.

7. A low-power supply anti-reverse connection protection circuit with indication of wide voltage range according to claim 1, characterized in that said load interface circuit (103) comprises a positive terminal v+ and a negative terminal V-;

the positive electrode terminal V+ and the negative electrode terminal V-are respectively connected with a post-stage circuit;

the output ends of the anti-reverse connection protection circuit (102) are respectively connected with the positive electrode terminal V+ and the negative electrode terminal V-.

8. The low-energy power supply reverse connection prevention protection circuit with indication in a wide voltage range according to claim 7, wherein a system power-on indication circuit (105) is arranged on the load interface circuit (103);

two ends of the system power-on indicating circuit (105) are respectively connected with the positive terminal V+ and the negative terminal V-.

9. The low-power supply reverse connection prevention protection circuit with indication of a wide voltage range according to claim 8, wherein the system power-on indication circuit (105) comprises a second current limiting resistor R2 and a second indication element LED2;

the input end of the second current limiting resistor is connected with the positive electrode terminal V+, and the second current limiting resistor R2 and the second indicating element LED2 are connected in series;

the output of the second indicator element LED2 is connected to the negative terminal V.

10. The low-energy-consumption power supply reverse connection prevention protection circuit with indication of a wide voltage range according to claim 1, wherein the external power supply interface circuit comprises an A end and a B end respectively;

the A-path circuit and the B-path circuit are respectively connected with the A end and the B end.

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