Protection circuit and electronic equipment

Abstract

The invention discloses a protection circuit and electronic equipment, the protection circuit comprises a surge protection device, n fuses and a plurality of resistors, each fuse is connected in series with (n-1) resistors in the plurality of resistors, and the n fuses connected in series with the (n-1) resistors are connected in parallel and are connected to an input negative line of protected equipment; one end of the surge protection device is electrically connected with an input positive line of the protected equipment, the other end of the surge protection device is electrically connected with (n-1) connection nodes, and the (n-1) connection nodes comprise a node where the first fuse is electrically connected with the first resistor and a node where the ith fuse is connected in series with the (n-1) resistors, the i-th resistor is electrically connected with the (i-1)-th resistor, i is equal to 2, 3,..., n-1, and n is an integer greater than 1.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of power supply technology, and in particular to a protection circuit and electronic equipment. Background Art

[0002] With the development of modern technology, the functions of electronic devices are becoming more and more powerful, which also brings about a sharp increase in power consumption, especially in the field of communication equipment. Due to the increase in power consumption, when the power supply voltage remains unchanged, the input current increases synchronously with the power consumption. Therefore, in the existing single fuse protection method, it is also necessary to increase the selection of fuses synchronously.

[0003] However, for high-current fuses, when the fault current is less than the rated current of the fuse, the fuse may not blow to protect the device, and when the fault current is greater than the rated current of the fuse, the fuse may take too long to blow. These problems may cause the equipment's fault point and PCB to smoke and catch fire, leading to serious accidents. Summary of the invention

[0004] The embodiments of the present application provide a protection circuit and an electronic device, which can solve the above-mentioned problem that the fuse triggering of large current is not sensitive and the fusing time is long.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, an embodiment of the present application provides a protection circuit, comprising: a surge protection device, n fuses and multiple resistors, wherein: each of the fuses is connected in series with (n-1) of the multiple resistors, and the n fuses of the (n-1) resistors in series are connected in parallel and connected to the negative input line of the protected device; one end of the surge protection device is electrically connected to the positive input line of the protected device, and the other end is electrically connected to (n-1) connection nodes, and the (n-1) connection nodes include: a node where the first fuse is electrically connected to the first resistor, and a node where the i-th resistor is electrically connected to the i-1th resistor among the (n-1) resistors connected in series with the i-th fuse, i=2,3,…,n-1, and n is an integer greater than 1.

[0007] In a second aspect, an embodiment of the present application provides an electronic device, which includes the protection circuit as described in the first aspect.

[0008] The protection circuit provided by the embodiment of the present application includes a surge protection device, n fuses and multiple resistors, wherein each of the fuses is connected in series with (n-1) of the multiple resistors, and the n fuses connected in series with the (n-1) resistors are connected in parallel and connected to the input negative line of the protected device; one end of the surge protection device is electrically connected to the input positive line of the protected device, and the other end is electrically connected to (n-1) connection nodes, and the (n-1) connection nodes include: a node where the first fuse is electrically connected to the first resistor, and a node where the i-th resistor is electrically connected to the i-1-th resistor among the (n-1) resistors connected in series with the i-th fuse, i=2,3,…,n-1, n is an integer greater than 1, so that the fault current generated by the surge protection device flows through the n fuses in sequence due to the existence of the resistors connected in series with each fuse, and the n fuses are blown in sequence, thereby reducing the current required to blow a single fuse and accelerating the blowing speed of the fuse.

[0009] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0011] Figure 1 A schematic diagram of a protection circuit provided by an exemplary embodiment of the present application is shown;

[0012] Figure 2 A schematic diagram of another protection circuit provided by an exemplary embodiment of the present application is shown;

[0013] Figure 3 A schematic diagram showing an application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown;

[0014] Figure 4 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown;

[0015] Figure 5 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown;

[0016] Figure 6 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown;

[0017] Figure 7 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown;

[0018] Figure 8 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown;

[0019] Fig. 9 A schematic diagram of a protection circuit provided by an exemplary embodiment of the present application is shown;

[0020] Fig.10 A schematic diagram of another protection circuit provided by an exemplary embodiment of the present application is shown;

[0021] Fig.11 A schematic structural diagram of an electronic device provided by an exemplary embodiment of the present application is shown. DETAILED DESCRIPTION

[0022] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0023] Figure 1 A schematic diagram of a protection circuit provided by an exemplary embodiment of the present application is shown. Figure 1 The protection circuit 100 includes: a surge protection device 11, n fuses 12 and multiple resistors 13, wherein: each of the fuses 12 is connected in series with (n-1) of the multiple resistors 13, and the n fuses of the (n-1) resistors in series are connected in parallel and connected to the input negative line 14 of the protected device; one end of the surge protection device 11 is electrically connected to the input positive line 15 of the protected device, and the other end is electrically connected to (n-1) connection nodes, and the (n-1) connection nodes include: a node where the first fuse 1201 is electrically connected to the first resistor 1301, and a node where the i-th resistor is electrically connected to the i-1-th resistor among the (n-1) resistors connected in series with the i-th fuse, i=2,3,…,n-1, and n is an integer greater than 1.

[0024] The resistor in the protection circuit of the embodiment of the present application may be a resistor in a practical sense, or may be realized by setting the routing of a printed circuit board (PCB).

[0025] In the embodiment of the present application, when the surge protection device 11 fails and a short circuit occurs, a fault current will be generated. The fault current first flows from the surge protection device 11 through the node where the first fuse 1201 is electrically connected to the first resistor 1301, and flows through the first fuse 1201, and the first fuse 1201 is blown first. The fault current also flows from the surge protection device 11 through the second connection node, through the first resistor connected in series with the second fuse, and then flows through the second fuse, and the second fuse is blown at this time. By analogy, the fault current also flows from the surge protection device 11 through the i-th connection node, through the (i-1)th resistor, the (i-2)th resistor, ..., the first resistor connected in series with the i-th fuse, and then flows through the i-th fuse, and the i-th fuse is blown at this time, and then the n-th fuse is blown, where i = 2, 3, ..., n-1, and n is an integer greater than 1. Therefore, through the protection circuit provided by the embodiment of the present application, the fault current can flow through n fuses in sequence due to the existence of a resistor in series with each fuse, and the n fuses are blown one after another, thereby reducing the current required to blow a single fuse and accelerating the blowing speed of the fuse.

[0026] Figure 2 FIG. 1 shows a schematic diagram of another protection circuit provided by an embodiment of the present application in an implementation manner, see Figure 2 The protection circuit 100 includes a surge protection device 11, n fuses 12, and a plurality of resistors 13, and may also include a protection switch 16. One end of the protection switch 16 is electrically connected to the input positive line 15, and the other end is electrically connected to the (n-1) and the connection point. The protection switch 16 turns on or off the electrical connection between the two ends of the protection switch 16 under the control of a control signal.

[0027] The situations in which the protection switch 16 triggers the control signal include but are not limited to detecting a fault such as over-temperature, over-current, or over-voltage in the system.

[0028] In the embodiment of the present application, the protection switch 16 is connected in parallel with the surge protection device 11. When other faults occur to the protected device except the failure of the surge protection device 11, the electrical connection between the two ends of the protection switch 16 is turned on by the control signal, and the fault current generated by other faults flows through the node where the first fuse 1201 is electrically connected to the first resistor 1301 by the protection switch 16, and flows through the first fuse 1201, and the first fuse 1201 is blown first. The fault current also flows through the first resistor connected in series with the second fuse by the protection switch 16 through the second connection node, and then flows through the second fuse, and the second fuse is blown at this time. By analogy, through the protection circuit provided by the embodiment of the present application, the fault current flows through the resistor connected in series with each fuse and then flows through each fuse through the protection switch 16 turned on by the control signal, so as to reach n fuses in sequence, and blow n fuses in sequence, thereby reducing the current required to blow a single fuse and accelerating the blowing speed of the fuse.

[0029] In one implementation, the above-mentioned surge protection device 11 may include at least one of the following: a transient voltage suppression diode, a varistor, a gas discharge tube, and a surge suppression transistor.

[0030] Figure 3 A schematic diagram showing an application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown in FIG. Figure 3 The protection circuit in this embodiment includes a surge protection device, two fuses, and resistors connected in series with the two fuses, namely, fuse 311 and resistor 312, fuse 321 and resistor 322. The surge protection device of the protection circuit is a transient voltage suppressor diode (TVS) 33.

[0031] Figure 4 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown in FIG. Figure 4 The protection circuit in this embodiment includes a surge protection device, two fuses, and resistors connected in series with the two fuses, namely, fuse 411 and resistor 412, fuse 421 and resistor 422. The surge protection device of the protection circuit is a varistor 43.

[0032] Figure 5 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown in FIG. Figure 5 The protection circuit in this embodiment includes a surge protection device, two fuses, resistors connected in series with the two fuses, and a protection switch, namely, fuse 511 and resistor 512, fuse 521 and resistor 522. The surge protection device of the protection circuit is TVS 53, and the protection switch is field effect transistor 541 and field effect transistor 542.

[0033] Figure 6 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown in FIG. Figure 6 The protection circuit in this embodiment includes a surge protection device, two fuses, resistors connected in series with the two fuses, and a protection switch, namely, fuse 611 and resistor 612, fuse 621 and resistor 622. The surge protection device of the protection circuit is a varistor 63, and the protection switch is a field effect transistor 641 and a field effect transistor 642.

[0034] Figure 7 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown in FIG. Figure 7 The protection circuit in this embodiment includes a surge protection device, two fuses, resistors connected in series with the two fuses, and a protection switch, namely, fuse 711 and resistor 712, fuse 721 and resistor 722. The surge protection device of the protection circuit is TVS 73, and the protection switch is relay 74.

[0035] Figure 8 A schematic diagram showing another application scenario of a protection circuit provided by an exemplary embodiment of the present application is shown in FIG. Figure 8 The protection circuit in this embodiment includes a surge protection device, two fuses, resistors connected in series with the two fuses, and a protection switch, namely, fuse 811 and resistor 812, fuse 821 and resistor 822. The surge protection device of the protection circuit is a varistor 83, and the protection switch is a relay 84.

[0036] In one implementation, the electrical parameters of the n fuses in the protection circuit are the same.

[0037] In the protection circuit of the embodiment of the present application, the electrical parameters of the n fuses are set to be the same to ensure that when the circuit is working normally, the current of the branch where each fuse is located remains consistent, preventing the current of each branch from being unbalanced and affecting the protection accuracy of the protection circuit.

[0038] In one implementation, parameters of the multiple resistors in the protection circuit are the same.

[0039] In the protection circuit of the embodiment of the present application, the parameters of multiple resistors in the protection circuit are set to be the same to ensure that when the circuit is working normally, the currents of the branches where the fuses and the resistors connected in series with the fuses are located remain consistent, thereby preventing the currents of the branches from being unbalanced and affecting the protection accuracy of the protection circuit.

[0040] In one implementation, the nominal melting heat energy I in the electrical parameters of the fuse in the protection circuit is 2T is greater than the surge energy or power-on impact pulse energy of the input port of the protected device.

[0041] In the embodiment of the present application, the selection of the fuse in the protection circuit also needs to meet certain requirements, such as the nominal melting heat energy I in the electrical parameters of the fuse. 2 T needs to meet the surge current requirement, which can be the nominal melting heat energy I in the electrical parameters of the fuse. 2 T is greater than the surge energy or power-on impact pulse energy of the input port of the protected device.

[0042] In one implementation, the product of the rated current value in the electrical parameters of the fuse in the protection circuit and the n and the derating factor is greater than the maximum input current of the protected device.

[0043] In the embodiment of the present application, the selection requirements for the fuse in the protection circuit may also include: the product of the rated current value in the electrical parameters of the fuse and the n and the derating factor is greater than the maximum input current of the protected device. For example, when n is 2 and the derating factor of the fuse in parallel is 0.85, the rated current value of the fuse*2*0.85 is required to be greater than the maximum input current of the protected device.

[0044] In one implementation, the n fuses in the protection circuit may be 2 fuses or 3 fuses, see Fig. 9 and Fig.10 .

[0045] Fig. 9 A schematic diagram of a protection circuit provided by an exemplary embodiment of the present application is shown. In this embodiment, n=2, and the protection circuit includes three parts. The first part includes two fuses and resistors connected in series with the two fuses, namely, fuse 911 and resistor 912, fuse 921 and resistor 922. The resistors 912 and 922 can be resistors in a practical sense, or they can be realized by setting the routing of the PCB. The second part includes a surge protection device 93, one end of which is connected to the access positive line 95, and the other end is connected to the connection node between the fuse 911 and the resistor 912. The third part includes a protection switch 94, one end of which is connected to the access positive line 95, and the other end is connected to the connection node between the fuse 911 and the resistor 912. The protection switch 94 is connected in parallel with the above-mentioned surge protection device 93.

[0046] In the embodiment of the present application, when the surge protection device 93 in the protection circuit fails and a short circuit occurs, due to the existence of resistor 912 and resistor 922, the fault current flows through the surge protection device 93 and fuse 911, and first fuses the fuse 911. After the fuse 911 is fused, the fault current still flows through the surge protection device 93, resistor 912, resistor 922 and fuse 921, and at this time, the fuse 921 is fused later. Through the protection circuit of the embodiment of the present application, the fault current can reach the fuse 912 and fuse 921 in sequence, so as to fuse the fuse 912 and fuse 921 successively, achieving the reduction of the current required to fuse a single fuse and accelerating the fusing speed of the fuse.

[0047] In addition, the protection switch 94 is connected in parallel with the surge protection device 93. When other faults occur in the protected device and are detected, the protection switch 94 is closed by triggering a control signal. Due to the existence of resistor 912 and resistor 922, the fault current flows through the protection switch 94 and fuse 911, and first fuses the fuse 911. After the fuse 911 is fused, the fault current still flows through the protection switch 94, resistor 912, resistor 922 and fuse 921, and at this time, the fuse 921 is fused later. Through the protection circuit of the embodiment of the present application, the fault current can reach the fuse 912 and fuse 921 in sequence, so as to fuse the fuse 912 and fuse 921 successively, achieving the reduction of the current required to fuse a single fuse and accelerating the fusing speed of the fuse. Among them, the triggering control signal of the protection switch may include, but is not limited to, detecting faults such as overheating, overcurrent, and overvoltage in the system.

[0048] Fig.10 Fig. shows a schematic diagram of another protection circuit provided by an exemplary embodiment of the present application. In this embodiment, n = 3, and the protection circuit includes three parts. The first part includes three fuses and resistors connected in series with the three fuses respectively, namely fuse 101, resistor 111 and resistor 112, fuse 102, resistor 121 and resistor 122, fuse 103, resistor 131 and resistor 132. The resistor can be an actual resistor or can be realized by setting the PCB trace. The second part includes a surge protection device 104. One end of the surge protection device 104 is connected to the access positive line 106, and the other end is connected to the connection node between the fuse 101 and the resistor 111, and is also connected to the connection node between the resistor 121 and the resistor 122. The third part includes a protection switch 105. One end of the protection switch 105 is connected to the access positive line 106, and the other end is connected to the connection node between the fuse 101 and the resistor 111, and is also connected to the connection node between the resistor 121 and the resistor 122. The protection switch 105 is connected in parallel with the above-mentioned surge protection device 104.

[0049] In the embodiment of the present application, when the surge protection device 104 in the protection circuit fails and a short circuit occurs, due to the existence of resistors 111 and 112, resistors 121 and 122, and resistors 131 and 132, the fault current flows through the surge protection device 104 and the fuse 101, and first melts the fuse 101. After the fuse 101 melts, the fault current still flows through the surge protection device 104, resistor 121, and fuse 102, and at this time, the fuse 102 melts again. After the fuse 102 melts, the fault current still flows through the surge protection device 104, resistor 122, resistors 131, 132, and fuse 103, and at this time, the fuse 103 melts later. Through the protection circuit of the embodiment of the present application, the fault current can reach the fuse 101, fuse 102, and fuse 103 in sequence, thereby melting the fuse 101, fuse 102, and fuse 103 successively, achieving a reduction in the current required to melt a single fuse and accelerating the melting speed of the fuse.

[0050] In addition, for the protection switch 105 connected in parallel with the surge protection device 104, the protection steps when detecting other faults of the protected device are similar to the above, and will not be elaborated here.

[0051] The embodiment of the present application also provides an electronic device, which includes the protection circuit in any of the above Figures 1 to 10 shown embodiments.

[0052] See Fig.11 , in the embodiment of the present application, the protection circuit 1101 described in the above embodiments can be arranged at the power input port 1102 of the electronic device 1100, so as to be able to provide timely and rapid protection for the electronic device.

[0053] In addition, the electronic device can also be other high-current electronic devices, and the above protection circuit can be arranged at the power input port of the high-current electronic device.

[0054] After considering the specification and practicing the invention disclosed herein, those skilled in the art will readily think of other embodiments of the present application. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and embodiments are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the claims.

[0055] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A protection circuit, It is characterized in that include: Surge protection devices, n fuses and multiple resistors, including: Each of the fuses is connected in series with (n-1) of the multiple resistors, and the n fuses connected in series with the (n-1) resistors are connected in parallel and connected to the negative input line of the protected device; One end of the surge protection device is electrically connected to the input positive line of the protected device, and the other end is electrically connected to (n-1) connection nodes, wherein the (n-1) connection nodes include: a node where the first fuse is electrically connected to the first resistor, and a node where the i-th resistor is electrically connected to the i-1th resistor among the (n-1) resistors connected in series with the i-th fuse, i=2, 3, ..., n-1, where n is an integer greater than 1.

2. The protection circuit according to claim 1, It is characterized in that Also includes: A protection switch, one end of which is electrically connected to the input positive line, and the other end of which is electrically connected to the (n-1) connection nodes. The protection switch switches on or off the electrical connection between the two ends of the protection switch under the control of a control signal.

3. The protection circuit according to claim 2, It is characterized in that The protection switch includes one of the following: a field effect tube, a relay.

4. The protection circuit according to claim 1, It is characterized in that The surge protection device includes at least one of the following: a transient voltage suppression diode, a varistor, a gas discharge tube, and a surge suppression transistor.

5. The protection circuit according to any one of claims 1 to 4, It is characterized in that The electrical parameters of the n fuses are the same.

6. The protection circuit according to claim 5, It is characterized in that The nominal melting heat energy I in the electrical parameters of the fuse 2 T is greater than the surge energy or power-on impact pulse energy of the input port of the protected device.

7. The protection circuit according to claim 5, It is characterized in that The product of the rated current value in the electrical parameters of the fuse, the n and the derating factor is greater than the maximum input current of the protected device.

8. The protection circuit according to any one of claims 1 to 4, It is characterized in that The parameters of the multiple resistors are the same.

9. The protection circuit according to claim 8, It is characterized in that The n is equal to 2 or 3.

10. An electronic device, It is characterized in that The protective circuit comprises the protection circuit described in any one of claims 1 to 9.

Images