Current-limiting protection circuit and circuit board
By designing the current limit protection circuit and using the current limit protection module to detect and control the power supply of the power of the power of the power of the power of the load circuit in the multiple output power circuit is solved, and the safe and stable operation of the load module and the improvement of the test efficiency are achieved.
Patent Information
- Application Number
- CN202420897495.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-26
- Publication Date
- 2025-03-25
- Estimated Expiration
- 2034-04-26
AI Technical Summary
In the prior art, when the power of the load circuit exceeds the preset value, a safety specification test is required, which requires a lot of time and effort.
Design a current limit protection circuit, including a power supply module, a sampling module, a load module and a current limit protection module. The current limit protection module detects whether the working current of the load module exceeds the preset value through the sampling module. If it exceeds, it sends a protection signal to stop power supply of the power module.
The current limit protection of the load module is realized to ensure that it always operates at a current not exceeding the preset value, thereby ensuring work safety and avoiding a large number of safety specification testing.
Smart Images
Figure CN222673901U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of protection circuits, and in particular to a current limiting protection circuit and a circuit board. Background Art
[0002] In the prior art, multi-output power supply circuits are used in various occasions. For example, a home appliance control circuit includes multiple output circuits, that is, multiple loads, such as a main control circuit responsible for load control, a display circuit responsible for display and partial signal detection, and a drive circuit responsible for motor control.
[0003] According to current safety regulations, when the power of a load circuit exceeds a preset value, it is necessary to meet safety regulations testing. As the current requirements for power supplies are increasing, when the current value output by the power supply circuit exceeds the overcurrent value corresponding to the entire circuit, the power output to a load circuit may exceed the preset value. Therefore, since the load circuit may receive power exceeding the preset value during operation, it is necessary to perform safety regulations testing on the load circuit. However, safety regulations testing for load circuits requires a lot of time and effort. Summary of the invention
[0004] The embodiment of the present application provides a protection circuit that can perform current limiting protection on a certain output load module in a power supply circuit with multiple outputs, so that the load module always works based on a current that does not exceed a preset value, thereby ensuring the working safety of the load module and avoiding spending a lot of time and effort on safety specification testing of the load module. The technical solution is as follows:
[0005] In a first aspect, an embodiment of the present application provides a current limiting protection circuit, and a method includes:
[0006] Power supply module, sampling module, first load module, second load module, current limiting protection module;
[0007] The first output end of the power module is connected to the input end of the sampling module, the first output end of the sampling module is connected to the input end of the first load module, the first output end of the power module outputs a first working current, and the power module supplies power to the first load module via the sampling module;
[0008] The second output end of the sampling module is connected to the input end of the current limiting protection module, and the first working current is transmitted to the current limiting protection module via the sampling module, so that the current limiting protection module detects whether the first working current exceeds a preset value;
[0009] The output end of the current limiting protection module is connected to the control end of the power module. When the current limiting protection module detects that the first working current exceeds a preset value, a protection signal output by the current limiting protection module is transmitted to the power module via the output end of the current limiting protection module, so that the power module stops supplying power to the first load module based on the protection signal.
[0010] The second output end of the power module is connected to the second load module so that the power module supplies power to the second load module.
[0011] In a second aspect, an embodiment of the present application provides a circuit board, which includes a current limiting protection circuit as proposed in the first aspect.
[0012] The beneficial effects brought about by the technical solutions provided by some embodiments of the present application include at least:
[0013] The current limiting protection circuit provided by the present application includes a power module, a sampling module, a first load module, a second load module, and a current limiting protection module. When the current limiting protection module detects through the sampling module that the first working current input to the first load module exceeds a preset value, it sends protection information to the power module so that the power module stops supplying power to the first load module without affecting the power supply to the second load module. In other words, the present application can perform current limiting protection for a certain output load module in a power supply circuit with multiple outputs, so that the load module always works based on a current that does not exceed a preset value, thereby ensuring the working safety of the load module and avoiding spending a lot of time and energy on safety specification testing of the load module. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0015] Figure 1 It is a structural schematic diagram of a power supply circuit for multiple loads provided in an embodiment of the present application;
[0016] Figure 2 is a structural schematic diagram of a current limiting protection circuit provided in an embodiment of the present application;
[0017] Figure 3 is a structural schematic diagram of a current limiting protection circuit provided in an embodiment of the present application;
[0018] Figure 4 is a structural schematic diagram of a current limiting protection circuit provided in an embodiment of the present application;
[0019] Figure 5 is a structural schematic diagram of a current limiting protection circuit provided in an embodiment of the present application;
[0020] Figure 6 It is a structural schematic diagram of a current limiting protection circuit provided in an embodiment of the present application. DETAILED DESCRIPTION
[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0022] In the description of the present application, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood in specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are an "or" relationship.
[0023] The present application is described in detail below with reference to specific embodiments.
[0024] Power supply circuits with multiple outputs are used in various occasions. For example, the control circuit of a home appliance includes multiple output circuits, that is, multiple loads, such as a main control circuit responsible for load control, a display circuit responsible for display and partial signal detection, and a drive circuit responsible for motor control.
[0025] like Figure 1, which is a schematic diagram of a power supply circuit for a multi-channel load provided in an embodiment of the present application, and the power supply circuit includes: a power supply module 101, a display panel module 102, and a main control panel module 103. In this embodiment, the output end of the power supply module 101 is connected to the display panel module 102 and the main control panel module 103, respectively, so as to send the working current corresponding to each module to the display panel module 102 and the main control panel module 103, respectively, so that the display panel module 102 works based on the working current corresponding to the display panel module 102, and the main control panel module 103 works based on the working current corresponding to the main control panel module 103.
[0026] According to current safety regulations, when the power of a load circuit exceeds a preset value, it is necessary to meet safety regulations testing. As the current requirements for power supplies are increasing, when the current value output by the power supply circuit exceeds the overcurrent value corresponding to the entire circuit, the power output to a load circuit may exceed the preset value. Therefore, since the load circuit may receive power exceeding the preset value during operation, it is necessary to perform safety regulations testing on the load circuit. However, safety regulations testing for load circuits requires a lot of time and effort.
[0027] In order to solve the above problems, the present application proposes a current limiting protection circuit. Figure 2 As shown, it is a structural schematic diagram of a current limiting protection circuit provided in an embodiment of the present application, and the current limiting protection circuit includes: a power supply module 201, a sampling module 202, a first load module 203, a second load module 204, and a current limiting protection module 205.
[0028] In this embodiment, the first output end of the power module 201 is connected to the input end of the sampling module 202, the first output end of the sampling module 202 is connected to the input end of the first load module 203, the first working current output by the power module 201 is transmitted to the first load module 203 via the sampling module 202, the first output end of the power module 201 outputs the first working current, and the power module 201 supplies power to the first load module 203 via the sampling module 202. The first load module 203 works based on the power supply of the power module 201. For example, the first load module 203 is as follows Figure 1 The display panel module shown displays a preset image based on the first working current output by the power module 201.
[0029] The second output end of the sampling module 202 is connected to the input end of the current limiting protection module, and the first working current is transmitted to the current limiting protection module via the sampling module 202, so that the current limiting protection module 205 detects whether the first working current exceeds the preset value. In other words, the current limiting protection module 205 samples the first working current output by the power module 301 based on the sampling module 202, so as to detect whether the current value of the first working current exceeds the preset value. The preset value can be an arbitrarily set value, for example, the preset value is 15V, which means that the first working current corresponding to the first load module 203 cannot exceed 15V, and the current limiting protection module 205 detects whether the current value of the first working current exceeds 15V.
[0030] The output end of the current limiting protection module 205 is connected to the input end of the power module 201. When the current limiting protection module 205 detects that the first working current exceeds the preset value, the protection signal output by the current limiting protection module 205 is transmitted to the power module 201 via the output end of the current limiting protection module 205, so that the power module 201 stops outputting the first working current to the first load module 203 based on the protection signal. The protection signal can be a high level or a low level signal. When the power module 201 receives the protection signal based on the input end of the power module 201, that is, the current value of the first working current exceeds the preset value, in order to protect the working safety of the first load module 203, the power module 201 stops outputting the first working current to the first load module 203, for example, the connection path between the power module 201 and the first load module 203 is cut off.
[0031] The second output terminal of the power module 201 is connected to the second load module 204, and the second output terminal of the power module 201 outputs a second working current. The second load module 204 works based on the power supply of the power module 201. The second load module 204 can be any load module, for example, the second load module 204 is Figure 1 The main control board module 103 is shown. The power module 201 stops supplying power to the first load module 203, which does not affect the second load module 204 to work based on the second working current.
[0032] The current limiting protection circuit provided by the present application includes a power module, a sampling module, a first load module, a second load module, and a current limiting protection module. When the current limiting protection module detects through the sampling module that the first working current input to the first load module exceeds a preset value, it sends protection information to the power module so that the power module stops supplying power to the first load module without affecting the power supply to the second load module. In other words, the present application can perform current limiting protection for a certain output load module in a power supply circuit with multiple outputs, so that the load module always works based on a current that does not exceed a preset value, thereby ensuring the working safety of the load module and avoiding spending a lot of time and energy on safety specification testing of the load module.
[0033] like Figure 3 , which is a schematic diagram of the structure of a current limiting protection circuit provided in an embodiment of the present application, the current limiting protection circuit includes: a power module 301, a sampling module 302, a first load module 303, a second load module 304, and a current limiting protection module 305. The connection method of the power module 301, the sampling module 302, the first load module 303, the second load module 304, and the current limiting protection module 305 is as follows: Figure 2 As shown, no further description is given here.
[0034] In this embodiment, the current limiting protection module 305 includes: an amplifying unit 3051, a comparing unit 3052, and a signal sending unit 3053. Among them, the input end of the amplifying unit 3051 is connected to the second output end of the sampling module 302, the output end of the amplifying unit 3051 is connected to the input end of the comparing unit 3052, and the output end of the comparing unit 3052 is connected to the input end of the comparing unit 3052. The first working current is sampled via the amplifying unit 3051 and input to the comparing unit 3052, so that the comparing unit 3052 detects whether the first working current exceeds the preset value. In order to improve the sampling stability of the first working current and the accuracy of judging whether the first working current exceeds the preset value, the first working current flowing through the sampling module 302 is sampled by the amplifying unit 3051. The comparing unit 3052 compares the first working current with the preset value.
[0035] The output end of the comparison unit 3052 is connected to the input end of the signal sending unit 3053, and the output end of the signal sending unit 3053 is connected to the input end of the power module 301. When the comparison unit 3052 detects that the first working current exceeds the preset value, the comparison unit 3052 switches from the off state to the on state, and based on the comparison unit 3052 in the on state, the signal sending unit 3053 sends a protection signal to the power module 301. So that the power module 301 stops outputting power to the first load module 303 based on the protection signal.
[0036] In other words, when the comparison unit 3052 detects that the current value of the first working current does not exceed the preset value, the comparison unit 3052 is in an off state, and the signal sending unit 3053 cannot send a protection signal to the power module 301. When the comparison unit 3052 detects that the current value of the first working current exceeds the preset value, the comparison unit 3052 switches from the off state to the on state, and based on the comparison unit 3052 in the on state, the signal sending unit 3053 sends a protection signal to the power module 301.
[0037] The current limiting protection circuit provided by the present application includes a power module, a sampling module, a first load module, a second load module, and a current limiting protection module. When the current limiting protection module detects through the sampling module that the first working current input to the first load module exceeds a preset value, it sends protection information to the power module so that the power module stops supplying power to the first load module without affecting the power supply to the second load module. In other words, the present application can perform current limiting protection for a certain output load module in a power supply circuit with multiple outputs, so that the load module always works based on a current that does not exceed a preset value, thereby ensuring the working safety of the load module and avoiding spending a lot of time and energy on safety specification testing of the load module.
[0038] like Figure 4 , which is a schematic diagram of the structure of a current limiting protection circuit provided in an embodiment of the present application, and the current limiting protection circuit includes: a power module 401, a sampling module 402, a first load module 403, a second load module 404, and a current limiting protection module 405. The connection method of the power module 401, the sampling module 402, the first load module 403, the second load module 404, and the current limiting protection module 405 is as follows: Figure 2 As shown, no further description is given here.
[0039] In this embodiment, the amplification unit 4051 includes: a first triode Q1, a second triode Q2, a first resistor R1, and a second resistor R2. The first end of the first resistor R1 is connected to the input end of the sampling module 402, the second end of the first resistor R1 is connected to the emitter of the first triode Q1, the base of the first triode Q1 is respectively connected to the first end of the second resistor R2, the base of the second triode Q1, and the collector of the second triode Q2, the collector of the first triode Q1 is connected to the comparison unit 4052, the second end of the second resistor R2 is grounded, and the emitter of the second triode Q2 is connected to the second output end of the sampling module 402.
[0040] The comparison unit includes: a third resistor R3 and a first voltage zener diode U1. The first end of the third resistor R3 and the gate of the first voltage zener diode U1 are respectively connected to the amplification unit 4051, the second end of the third resistor R3 is connected to the anode of the first voltage zener diode U1, and the cathode of the first voltage zener diode U1 is connected to the input end of the signal sending unit 4053.
[0041] The power module 401 includes: a power control unit 4011 and a signal receiving unit 4012. The input end of the signal receiving unit 4012 is connected to the output end of the signal sending unit 4053, and the output end of the signal receiving unit 4053 is connected to the first end of the power control unit 4011. The protection signal is input to the power control unit via the signal receiving unit 4012, so that the power control unit 4011 stops outputting the first working current.
[0042] Figure 4 The working principle of the current limiting protection circuit shown is as follows:
[0043] The first transistor Q1 and the second transistor Q2 are PNP transistors, and the characteristics of the two transistors are basically consistent. When the current value of the first working current is less than the preset value, the second transistor Q2 is turned on and works in the amplification area, so the collector current of the second transistor Q2 is (V1-Vbe) / R2, where Vbe is the base voltage of the second transistor Q2, and the emitter current of the first transistor Q1 is (Vx-V1) / R1, where Vx is the voltage at the input end of the acquisition module 402.
[0044] When the current value of the first working current is less than the set value, the voltage Vx at the input end of the acquisition module 402 is small, and the emitter current (Vx-V1) / R1 of the first transistor Q1 is less than U1 / R3, wherein U1 is the rated working voltage of the Zener diode U1, that is, the emitter current of the first transistor Q1 is less than U1 / R3, the first Zener diode U1 is in the off state, and the signal sending unit 4053 does not work.
[0045] When the current value of the first working current is greater than or equal to the set value, the voltage Vx at the input end of the acquisition module 402 increases, and the emitter current (Vx-V1) / R1 of the first transistor Q1 is greater than or equal to U1 / R3, that is, the emitter current of the first transistor Q1 is greater than or equal to U1 / R3, and the first Zener diode U1 switches from the off state to the on state. The signal sending unit 4053 works based on the first Zener diode U1 in the on state and sends a protection signal to the signal receiving unit 4012.
[0046] based on Figure 4 The current limiting protection circuit shown in Figure 5 As shown, it is a structural schematic diagram of another current limiting protection circuit provided in an embodiment of the present application. In this embodiment, the signal sending unit 4053 includes: a first light-emitting unit PC1A, a first light-receiving unit PC1B, a fourth resistor R4, and a fifth resistor R5. Among them, the cathode of the first light-emitting unit PC1A is respectively connected to the output end of the comparison unit 4052 and the first end of the fourth resistor R4, the anode of the first light-emitting unit PC1A is respectively connected to the first end of the fourth resistor R4 and the fifth resistor R5, and the second end of the fifth resistor R5 is connected to the input end of the sampling module.
[0047] The signal receiving unit includes: a first capacitor C1. The emitter of the first light receiving unit PC1B is connected to the first end of the first capacitor C1 and then grounded, and the collector of the first light receiving unit PC1B is connected to the second end of the first capacitor C1 and the first end of the power control unit 4011 respectively.
[0048] The sampling module includes: a sixth resistor R6, wherein the first end of the sixth resistor R6 is respectively connected to the first output end of the power module 401 and the first input end of the current limiting protection module 405, and the second end of the sixth resistor R6 is respectively connected to the second input end of the current limiting protection module 405 and the input end of the first load module 403.
[0049] like Figure 5 The working principle of the current limiting protection circuit shown is as follows:
[0050] When the current value of the first working current is greater than or equal to the set value, the first voltage zener diode U1 switches from the off state to the on state, and the light emitting unit PC1A emits light based on the first voltage zener diode U1 in the on state, and sends the light signal to the first light receiving unit PC1B as a protection signal. The first light receiving unit PC1B is turned on based on the light signal and sends a low level signal to the power control unit 4011. When the power control unit 4011 receives the low level signal through the first end of the power control unit 4011, it stops sending the first working current to the first load module 403.
[0051] In this embodiment, the protection signal is sent between the signal sending unit 4053 and the signal receiving unit 4012 via an optocoupler diode and an optocoupler transistor, thereby ensuring the isolation between the current limiting protection module 405 and the power supply module 401 .
[0052] The current limiting protection circuit provided by the present application includes a power module, a sampling module, a first load module, a second load module, and a current limiting protection module. When the current limiting protection module detects through the sampling module that the first working current input to the first load module exceeds a preset value, it sends protection information to the power module so that the power module stops supplying power to the first load module without affecting the power supply to the second load module. In other words, the present application can perform current limiting protection for a certain output load module in a power supply circuit with multiple outputs, so that the load module always works based on a current that does not exceed a preset value, thereby ensuring the working safety of the load module and avoiding spending a lot of time and energy on safety specification testing of the load module.
[0053] like Figure 6 , which is a schematic diagram of the structure of a current limiting protection circuit provided in an embodiment of the present application, and the current limiting protection circuit includes: a power module 501, a sampling module 502, a first load module 503, a second load module 504, and a current limiting protection module 505. The connection method of the power module 501, the sampling module 502, the first load module 503, the second load module 504, and the current limiting protection module 505 is as follows: Figure 2 As shown, no further description is given here.
[0054] In this embodiment, the power module 401 also includes: a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, a ninth capacitor C9, a second voltage regulator diode U2, a first electrolytic capacitor E1, a second electrolytic capacitor E2, a third electrolytic capacitor E3, a second light-emitting unit PC2A, a second light-receiving unit PC2B, a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, a first winding T1, and a second winding T2;
[0055] The first end of the seventh resistor R7 is respectively connected to the first end of the eighth resistor R8, the first end of the second capacitor C2, the first end of the third capacitor C3, and the input end of the first winding T1; the second end of the seventh resistor R7 is respectively connected to the second end of the eighth resistor R8, the first end of the ninth resistor R9, and the first end of the tenth resistor R10; the second end of the ninth resistor R9 is respectively connected to the second end of the tenth resistor R10, the cathode of the first diode D1, and the second end of the second capacitor C2; the anode of the first diode D1 is connected to the first end of the eleventh resistor R11; the second end of the eleventh resistor R11 is respectively connected to the input end of the first winding T1 and the second end of the power control unit 4011.
[0056] The collector of the second light receiving unit PC2B is connected to the collector of the first light receiving unit PC1B, and the emitter of the second light receiving unit PC2B is connected to the emitter of the first light receiving unit PC1B.
[0057] The output end of the first winding T1 is respectively connected to the positive electrode of the second diode D2 and the first end of the fifth capacitor C5, the second end of the fifth capacitor C5 is connected to the first end of the twelfth resistor R12, the second end of the twelfth resistor R12 is respectively connected to the negative electrode of the second diode D2 and the input end of the sampling module, the first end of the sixth capacitor C6 is respectively connected to the first end of the first electrolytic capacitor E1 and the first load module 503, and the second end of the sixth capacitor C6 is respectively connected to the second end of the first electrolytic capacitor E1 and then grounded.
[0058] The third end of the power control unit 4011 is respectively connected to the first end of the seventh capacitor C7 and the cathode of the third diode D3, the anode of the third diode D3 is respectively connected to the first end of the fourth diode D4 and the first end of the second electrolytic capacitor E2, the cathode of the fourth diode D4 is respectively connected to the first end of the twelfth resistor R12, the second end of the twelfth resistor R12 is respectively connected to the first input end of the second winding T2, the first end of the eighth capacitor C8, and the anode of the fifth diode D5, the second end of the seventh capacitor C7 is respectively connected to the second end of the second electrolytic capacitor E2 and the second input end of the second winding T2 and then grounded, the second end of the eighth capacitor C8 is respectively connected to the first end of the thirteenth resistor R13, the second end of the thirteenth resistor R13 is respectively connected to the cathode of the fifth diode D5, the first end of the third electrolytic capacitor E3, and the second load module 504, and the second end of the third electrolytic capacitor E3 is grounded.
[0059] The positive electrode of the second light-emitting unit PC2A is connected to the first end of the fourteenth resistor R14 and the first end of the fifteenth resistor R15, the second end of the fourteenth resistor R14 is respectively connected to the first load module and the first end of the seventeenth resistor R17, the negative electrode of the second light-emitting unit PC2A is respectively connected to the second end of the fifteenth resistor R15, the first end of the ninth capacitor C9, and the negative electrode of the second voltage-stabilizing diode U2, the second end of the ninth capacitor C9 is connected to the first end of the sixteenth resistor R16, the second end of the sixteenth resistor R16 is respectively connected to the second end of the seventeenth resistor R17, the first end of the eighteenth resistor R18, and the gate of the second voltage-stabilizing diode U2, the second end of the eighteenth resistor R18 is connected to the positive electrode of the second voltage-stabilizing diode U2 and then grounded.
[0060] Figure 6 The working principle of the current limiting protection circuit shown in Figure 5 , I will not go into details here.
[0061] The current limiting protection circuit provided by the present application includes a power module, a sampling module, a first load module, a second load module, and a current limiting protection module. When the current limiting protection module detects through the sampling module that the first working current input to the first load module exceeds a preset value, it sends protection information to the power module so that the power module stops supplying power to the first load module without affecting the power supply to the second load module. In other words, the present application can perform current limiting protection for a certain output load module in a power supply circuit with multiple outputs, so that the load module always works based on a current that does not exceed a preset value, thereby ensuring the working safety of the load module and avoiding spending a lot of time and energy on safety specification testing of the load module.
[0062] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.
Claims
1. A current limiting protection circuit, characterized in that: The circuit comprises: Power supply module, sampling module, first load module, second load module, current limiting protection module; The first output end of the power module is connected to the input end of the sampling module, the first output end of the sampling module is connected to the input end of the first load module, the first output end of the power module outputs a first working current, and the power module supplies power to the first load module via the sampling module; The second output end of the sampling module is connected to the input end of the current limiting protection module, and the first working current is transmitted to the current limiting protection module via the sampling module, so that the current limiting protection module detects whether the first working current exceeds a preset value; The output end of the current limiting protection module is connected to the control end of the power module. When the current limiting protection module detects that the first working current exceeds a preset value, the protection signal output by the current limiting protection module is transmitted to the power module via the output end of the current limiting protection module, so that the power module stops supplying power to the first load module based on the protection signal. The second output end of the power module is connected to the second load module, and the power module supplies power to the second load module.
2. The current limiting protection circuit according to claim 1, characterized in that: The current limiting protection module includes: an amplification unit, a comparison unit, and a signal sending unit; The input end of the amplifying unit is connected to the second output end of the sampling module, the output end of the amplifying unit is connected to the input end of the comparing unit, the output end of the comparing unit is connected to the input end of the comparing unit, the first working current is sampled by the amplifying unit and input to the comparing unit, so that the comparing unit detects whether the first working current exceeds the preset value; The output end of the comparison unit is connected to the input end of the signal sending unit, and the output end of the signal sending unit is connected to the control end of the power module. When the comparison unit detects that the first operating current exceeds the preset value, the comparison unit switches from the off state to the on state. Based on the comparison unit in the on state, the signal sending unit sends the protection signal to the power module.
3. The current limiting protection circuit according to claim 2, characterized in that: The amplifying unit comprises: a first triode, a second triode, a first resistor, and a second resistor; The first end of the first resistor is connected to the input end of the sampling module, the second end of the first resistor is connected to the emitter of the first triode, the base of the first triode is respectively connected to the first end of the second resistor, the base of the second triode, and the collector of the second triode, the collector of the first triode is connected to the comparing unit, the second end of the second resistor is grounded, and the emitter of the second triode is connected to the second output end of the sampling module.
4. The current limiting protection circuit according to claim 2, characterized in that: The comparison unit includes: a third resistor and a first voltage stabilizing diode; The first end of the third resistor and the gate of the first voltage-stabilizing diode are respectively connected to the amplifying unit, the second end of the third resistor is connected to the anode of the first voltage-stabilizing diode, and the cathode of the first voltage-stabilizing diode is connected to the input end of the signal sending unit.
5. The current limiting protection circuit according to claim 2, characterized in that: The signal sending unit includes: a first light emitting unit, a first light receiving unit, a fourth resistor, and a fifth resistor; The cathode of the first light-emitting unit is connected to the output end of the comparison unit and the first end of the fourth resistor, respectively; the anode of the first light-emitting unit is connected to the first ends of the fourth resistor and the fifth resistor, respectively; the second end of the fifth resistor is connected to the input end of the sampling module; and the first light receiving unit is connected to the control end of the power supply module.
6. The current limiting protection circuit according to claim 5, characterized in that: The power module includes: a power control unit and a signal receiving unit; The input end of the signal receiving unit is connected to the output end of the signal sending unit, the output end of the signal receiving unit is connected to the first end of the power control unit, and the protection signal is input into the power control unit via the signal receiving unit so that the power control unit stops supplying power to the first load module.
7. The current limiting protection circuit according to claim 6, characterized in that: The signal receiving unit includes: a first capacitor; The emitter of the first light receiving unit is connected to the first end of the first capacitor and then grounded, and the collector of the first light receiving unit is respectively connected to the second end of the first capacitor and the first end of the power control unit.
8. The current limiting protection circuit according to claim 1, characterized in that: The sampling module comprises: a sixth resistor; The first end of the sixth resistor is respectively connected to the first output end of the power module and the first input end of the current limiting protection module, and the second end of the sixth resistor is respectively connected to the second input end of the current limiting protection module and the input end of the first load module.
9. The current limiting protection circuit according to claim 7, characterized in that: The power module also includes: a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a ninth capacitor, a second voltage regulator diode, a first electrolytic capacitor, a second electrolytic capacitor, a third electrolytic capacitor, a first diode, a second diode, a third diode, a fourth diode, a fifth diode, a first winding, a second winding, a second light-emitting unit, and a second light-receiving unit; The first end of the seventh resistor is respectively connected to the first end of the eighth resistor, the first end of the second capacitor, the first end of the third capacitor, and the input end of the first winding; the second end of the seventh resistor is respectively connected to the second end of the eighth resistor, the first end of the ninth resistor, and the first end of the tenth resistor; the second end of the ninth resistor is respectively connected to the second end of the tenth resistor, the cathode of the first diode, and the second end of the second capacitor; the anode of the first diode is connected to the first end of the eleventh resistor; and the second end of the eleventh resistor is respectively connected to the input end of the first winding and the second end of the power control unit; The collector of the second light receiving unit is connected to the collector of the first light receiving unit, and the emitter of the second light receiving unit is connected to the emitter of the first light receiving unit; The output end of the first winding is respectively connected to the positive electrode of the second diode and the first end of the fifth capacitor, the second end of the fifth capacitor is connected to the first end of the twelfth resistor, the second end of the twelfth resistor is respectively connected to the negative electrode of the second diode and the input end of the sampling module, the first end of the sixth capacitor is respectively connected to the first end of the first electrolytic capacitor and the first load module, and the second end of the sixth capacitor is respectively connected to the second end of the first electrolytic capacitor and then grounded; The third end of the power control unit is respectively connected to the first end of the seventh capacitor and the cathode of the third diode, the anode of the third diode is respectively connected to the first end of the fourth diode and the first end of the second electrolytic capacitor, the cathode of the fourth diode is respectively connected to the first end of the twelfth resistor, the second end of the twelfth resistor is respectively connected to the first input end of the second winding, the first end of the eighth capacitor, and the anode of the fifth diode, the second end of the seventh capacitor is respectively connected to the second end of the second electrolytic capacitor and the second input end of the second winding and then grounded, the second end of the eighth capacitor is respectively connected to the first end of the thirteenth resistor, the second end of the thirteenth resistor is respectively connected to the cathode of the fifth diode, the first end of the third electrolytic capacitor, and the second load, and the second end of the third electrolytic capacitor is grounded; The positive electrode of the second light-emitting unit is connected to the first end of the fourteenth resistor and the first end of the fifteenth resistor, the second end of the fourteenth resistor is respectively connected to the first load module and the first end of the seventeenth resistor, the negative electrode of the second light-emitting unit is respectively connected to the second end of the fifteenth resistor, the first end of the ninth capacitor, and the negative electrode of the second voltage-stabilizing diode, the second end of the ninth capacitor is connected to the first end of the sixteenth resistor, the second end of the sixteenth resistor is respectively connected to the second end of the seventeenth resistor, the first end of the eighteenth resistor, and the gate of the second voltage-stabilizing diode, and the second end of the eighteenth resistor is connected to the positive electrode of the second voltage-stabilizing diode and then grounded.
10. A circuit board, characterized in that: The circuit board includes the current limiting protection circuit as described in any one of claims 1-9.