Current detection circuit, overcurrent protection circuit and display device

Abstract

The invention relates to the technical field of display, and discloses a current detection circuit, an overcurrent protection circuit and a display device.The current detection circuit comprises a current sampling sub-circuit and a voltage comparison sub-circuit, the current sampling sub-circuit is coupled with the negative input end of a load, the negative input end is coupled with a grounding end and a secondary winding through a divider resistor, and the voltage comparison sub-circuit is coupled with the grounding end of the load. The voltage comparison sub-circuit is configured to generate a sampling voltage according to the current flowing through the divider resistor, is coupled with the current sampling sub-circuit and is configured to receive the sampling voltage, output a detection signal with a first level in response to the sampling voltage being greater than a reference voltage, and output a detection signal with a second level in response to the sampling voltage being less than the reference voltage; the current sampling sub-circuit can directly collect the sampling voltage of the loop where the secondary winding is located, the sampling voltage is compared with the reference voltage, and therefore whether the current of the loop where the secondary winding is located is too large or not can be judged more accurately.

Description

Current detection circuit, overcurrent protection circuit and display device Technical Field

[0001] The present application relates to the field of display technology and provides a current detection circuit, an overcurrent protection circuit and a display device. Background Art

[0002] Currently, current and other data are typically collected from the transformer's primary winding circuit, and then converted into the output load voltage. This method is limited by the performance parameters of the transformer's primary windings, resulting in low accuracy of the collected current and large errors in the converted output load voltage, hindering accurate setting and protection of the output load. Furthermore, even when the load current is directly sampled, the reference voltage used for comparison is affected by load variations, resulting in significant deviations between the overcurrent protection setting and the actual test value.

[0003] Summary of the Invention

[0004] Embodiments of the present application provide a current detection circuit, an overcurrent protection circuit, and a display device for more accurately determining whether the current in the loop where the secondary winding is located is too large.

[0005] The specific technical solutions provided in this application are as follows:

[0006] In a first aspect, an embodiment of the present application provides a current detection circuit, comprising: a current sampling subcircuit and a voltage comparison subcircuit;

[0007] The current sampling subcircuit is coupled to the negative input terminal of the load, the negative input terminal is coupled to the ground terminal and the secondary winding through a voltage divider resistor, and is configured to generate a sampling voltage according to the current flowing through the voltage divider resistor;

[0008] The voltage comparison subcircuit is coupled to the current sampling subcircuit and is configured to receive a sampling voltage; output a detection signal having a first level in response to the sampling voltage being greater than a reference voltage; and output a detection signal having a second level in response to the sampling voltage being less than the reference voltage.

[0009] Optionally, the device further includes a reference generation subcircuit coupled to the voltage comparison subcircuit;

[0010] The reference generation subcircuit is configured to perform voltage conversion on the power supply voltage to obtain a reference voltage, and output the reference voltage to the voltage comparison subcircuit.

[0011] Optionally, the reference generation subcircuit includes: a voltage conversion chip, a first capacitor, and a second capacitor;

[0012] The input end of the voltage conversion chip is used to receive the power supply voltage, and the output end of the voltage conversion chip is coupled to the voltage comparison sub-circuit and is configured to perform voltage conversion on the power supply voltage to obtain a reference voltage;

[0013] A first end of the first capacitor is coupled to the input end of the voltage conversion chip, and a second end of the first capacitor is grounded;

[0014] A first end of the second capacitor is coupled to the output end of the voltage conversion chip, and a second end of the second capacitor is grounded.

[0015] Optionally, the current sampling subcircuit includes: an operational amplifier, a first resistor, and a second resistor;

[0016] The non-inverting input terminal of the operational amplifier is coupled to the negative input terminal;

[0017] An inverting input terminal of the operational amplifier is grounded via a first resistor;

[0018] A first end of the first resistor is grounded, and a second end of the first resistor is coupled to the inverting input terminal;

[0019] The first end of the second resistor is coupled to the second end of the first resistor, and the second end of the second resistor is coupled to the output end of the operational amplifier.

[0020] Optionally, the voltage comparison subcircuit includes a comparison module and an output module coupled to each other;

[0021] A comparison module is configured to compare the received sample voltage with a reference voltage;

[0022] The output module is configured to output a detection signal having a first level, or output a detection signal having a second level.

[0023] Optionally, the comparison module includes: a comparator, a positive input terminal of the comparator coupled to the output terminal of the operational amplifier, a negative input terminal of the comparator coupled to the output terminal of the reference generation subcircuit, and an output terminal of the comparator coupled to the output module;

[0024] The output module includes: a switch tube, a control end of the switch tube is coupled to the output end of the comparator, a first electrode of the switch tube is coupled to the pull-up resistor, and a second electrode of the switch tube is grounded.

[0025] Optionally, the voltage comparison sub-circuit further includes: a third resistor, a third capacitor, a fourth resistor and a fifth resistor;

[0026] A first end of the third resistor is coupled to the power supply voltage receiving terminal of the comparator, a second end of the third resistor is coupled to the first end of the third capacitor, and a second end of the third capacitor is grounded;

[0027] A first end of the fourth resistor is coupled to the first end of the third capacitor, a second end of the fourth resistor is coupled to the first end of the fifth resistor, and a second end of the fifth resistor is grounded.

[0028] In a second aspect, an embodiment of the present application further provides an overcurrent protection circuit, comprising: the above-mentioned current detection circuit and current protection circuit;

[0029] a current detection circuit, configured to output a detection signal having a first level;

[0030] The current protection circuit performs current protection on the loop where the secondary winding is located in response to a detection signal with a first level.

[0031] In a third aspect, an embodiment of the present application further provides a display device comprising the above-mentioned overcurrent protection circuit.

[0032] In a fourth aspect, an embodiment of the present application further provides a current detection method, comprising:

[0033] The current sampling subcircuit generates a sampling voltage according to the current flowing through the voltage divider resistor coupled to the secondary winding;

[0034] The voltage comparison subcircuit outputs a detection signal having a first level in response to the sampling voltage being greater than the reference voltage; and outputs a detection signal having a second level in response to the sampling voltage being less than the reference voltage.

[0035] The beneficial effects of this application are as follows:

[0036] In summary, an embodiment of the present application provides a current detection circuit, an overcurrent protection circuit and a display device. The current detection circuit includes: a current sampling subcircuit and a voltage comparison subcircuit. The current sampling subcircuit is coupled to the negative input terminal of the load, and the negative input terminal is coupled to the ground terminal and the secondary winding through a voltage divider resistor. The current sampling subcircuit is configured to generate a sampling voltage according to the current flowing through the voltage divider resistor. The voltage comparison subcircuit is coupled to the current sampling subcircuit and is configured to receive the sampling voltage. In response to the sampling voltage being greater than a reference voltage, the voltage comparison subcircuit outputs a detection signal with a first level, and in response to the sampling voltage being less than the reference voltage, the voltage comparison subcircuit outputs a detection signal with a second level. The above-mentioned current sampling subcircuit can directly collect the sampling voltage of the loop where the secondary winding is located, and then compare the sampling voltage with the reference voltage, so as to more accurately determine whether the current in the loop where the secondary winding is located is too large.

[0037] Other features and advantages of the present application will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present application. The purposes and other advantages of the present application can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0039] FIG1 is a schematic diagram of a circuit connection for current detection in a loop where a primary winding is located in the related art;

[0040] FIG2 is a connection diagram of a current detection in an embodiment of the present application;

[0041] FIG3 is a circuit connection diagram of the current detection circuit and the loop where the secondary winding is located in an embodiment of the present application;

[0042] FIG4 is a circuit connection diagram of a current sampling sub-circuit in an embodiment of the present application;

[0043] FIG5 is a circuit connection diagram of a voltage comparison sub-circuit in an embodiment of the present application;

[0044] FIG6 is a flow chart of a current detection method in an embodiment of the present application. DETAILED DESCRIPTION

[0045] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of the technical solutions of this application, but not all of them. Based on the embodiments described in this application document, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the technical solutions of this application.

[0046] The terms "first," "second," and the like in the description and claims of the present invention and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments of the present invention described herein can be practiced using orders other than those illustrated or described herein.

[0047] In the related art, as shown in Figure 1, to determine whether the transformer's load current is excessive, current sampling is performed in the primary winding's loop. The sampled current is then converted to obtain the load current value. However, due to factors such as the primary winding's inherent performance parameters, the accuracy of the sampled current is relatively poor. Furthermore, changes in the load during operation in the related art can affect the accuracy of the reference comparison voltage, leading to significant deviations in the load current comparison.

[0048] The preferred embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0049] 2 , in an embodiment of the present application, a current detection circuit includes: a current sampling sub-circuit 10 and a voltage comparison sub-circuit 20 .

[0050] Referring to Figure 3, the transformer's secondary winding circuit includes the secondary winding, a voltage divider resistor, a load, a diode, and a filter capacitor. The detailed operation is omitted here. The current sampling subcircuit 10 is coupled to the negative input terminal of the load. This negative input terminal is coupled to ground and the secondary winding via the voltage divider resistor. This means the load is connected to ground after passing through the connected voltage divider resistor.

[0051] During implementation, the current sampling subcircuit 10 is configured to generate a sampled voltage based on the current flowing through the voltage divider resistor. Specifically, after receiving magnetic field energy from the primary winding, the secondary winding transfers this magnetic field energy as electrical energy to the diode, filter capacitor, load, and voltage divider resistor. The current sampling subcircuit 10 then samples the current flowing through the voltage divider resistor and obtains a sampled voltage.

[0052] Considering that the resistance of the voltage divider resistor is relatively small, the sampled voltage collected is amplified in the embodiment of the present application. Referring to FIG. 4 , the current sampling subcircuit 10 includes an operational amplifier, a first resistor R1 and a second resistor R2 .

[0053] The non-inverting input of the operational amplifier is coupled to the negative input, i.e., the sampled voltage enters the operational amplifier via the non-inverting input. The inverting input of the operational amplifier is grounded via a first resistor R1, i.e., the inverting input of the operational amplifier is grounded. The first end of the first resistor R1 is grounded, and the second end of the first resistor R1 is coupled to the inverting input. The first end of the second resistor R2 is coupled to the second end of the first resistor R1, and the second end of the second resistor R2 is coupled to the output of the operational amplifier, i.e., the second resistor R2 is connected between the inverting input and the output of the operational amplifier.

[0054] During implementation, the resistance values ​​of the first resistor R1 and the second resistor R2 need to be adjusted accordingly, so that the voltage of the voltage divider resistor can be amplified to a level suitable for comparison with the reference voltage.

[0055] In addition, the current detection circuit further includes a reference generation sub-circuit 30 , which is coupled to the voltage comparison sub-circuit 20 .

[0056] During implementation, the reference generation sub-circuit 30 is configured to perform voltage conversion on the power supply voltage to obtain a reference voltage, and output the reference voltage to the voltage comparison sub-circuit 20 .

[0057] Different from the method of generating the reference voltage in the related art, the reference voltage in the embodiment of the present application is generated based on the power supply voltage and a voltage conversion chip with a voltage stabilizing function. Moreover, the above-mentioned reference generation subcircuit 30 is relatively independently set, and the generated reference voltage is not affected by load fluctuations.

[0058] 5 , the reference generation sub-circuit 30 includes a voltage conversion chip, a first capacitor C1 and a second capacitor C2 .

[0059] The input end of the voltage conversion chip is used to receive the power supply voltage. The output end of the voltage conversion chip is coupled to the voltage comparison sub-circuit 20 and is configured to perform voltage conversion on the power supply voltage to obtain a reference voltage.

[0060] During implementation, the voltage conversion chip directly performs voltage conversion on the received power supply voltage to obtain a reference voltage, and then transmits the reference voltage to the voltage comparison sub-circuit 20 .

[0061] It should be noted that, to make the generated reference voltage more accurate, the voltage conversion chip is further connected to voltage-stabilizing capacitors. The first end of the first capacitor C1 is coupled to the input terminal of the voltage conversion chip, and the second end of the first capacitor C1 is grounded. The first end of the second capacitor C2 is coupled to the output terminal of the voltage conversion chip, and the second end of the second capacitor C2 is grounded.

[0062] After amplifying the sampled voltage, the voltage is further compared using the voltage comparison sub-circuit 20. As shown in FIG5 , the voltage comparison sub-circuit 20 is coupled to the current sampling sub-circuit 10 and is configured to receive the sampled voltage. In response to the sampled voltage being greater than a reference voltage, the circuit outputs a detection signal having a first level. Furthermore, in response to the sampled voltage being less than the reference voltage, the circuit outputs a detection signal having a second level.

[0063] During implementation, the voltage comparison sub-circuit 20 compares the voltage between the sampled voltage and the reference voltage, and outputs different detection signals when the comparison results are different.

[0064] Specifically, the voltage comparison sub-circuit 20 includes a comparison module and an output module coupled to each other.

[0065] The comparison module is configured to compare the received sample voltage with a reference voltage.

[0066] During implementation, the current sampling sub-circuit 10 outputs the sampled voltage to the comparison module. After receiving the sampled voltage and the reference voltage, the comparison module compares the sampled voltage with the reference voltage.

[0067] 5 , the comparison module includes a comparator, wherein the positive input of the comparator is coupled to the output of the operational amplifier, the negative input of the comparator is coupled to the output of the reference generation sub-circuit 30 , and the output of the comparator is coupled to the output module.

[0068] During the implementation process, the positive input terminal of the comparator is used to receive the sampling voltage output by the output terminal of the operational amplifier, and the negative input terminal of the comparator is used to receive the reference voltage output by the reference generation sub-circuit 30. Furthermore, after obtaining the comparison result between the sampling voltage and the reference voltage, the comparator outputs the above comparison result through the output terminal.

[0069] The output module is configured to output a detection signal having a first level, or output a detection signal having a second level.

[0070] After the comparison module compares the sampling voltage with the reference voltage, the output module outputs a detection signal with a first level when the sampling voltage is greater than the reference voltage; the output module outputs a detection signal with a second level when the sampling voltage is less than the reference voltage.

[0071] 5 , the output module includes a switch tube, a control terminal of the switch tube coupled to the output terminal of the comparator, a first terminal of the switch tube coupled to the pull-up resistor, and a second terminal of the switch tube grounded.

[0072] As shown in FIG5 , after receiving the signal from the output terminal of the comparator, the switch tube outputs a high level through the first electrode of the switch tube coupled to the pull-up resistor, or outputs a low level through the second electrode of the switch tube connected to the ground.

[0073] During the implementation process, after outputting a detection signal with a first level at the output end of the comparator, or outputting a detection signal with a second level, the output module converts the above-mentioned detection signal with the first level into a high-level output through a switching tube, and the output module converts the above-mentioned detection signal with the second level into a low-level output through a switching tube.

[0074] 5 , the voltage comparison sub-circuit 20 further includes a third resistor R3 , a third capacitor C3 , a fourth resistor R4 , and a fifth resistor R5 .

[0075] In order to make the output signal of the switching tube more accurate, in the embodiment of the present application, resistors and capacitors for filtering, current limiting, etc. are also provided.

[0076] 5 , a first terminal of the third resistor R3 is coupled to the power voltage receiving terminal of the comparator, a second terminal of the third resistor R3 is coupled to a first terminal of the third capacitor C3 , and a second terminal of the third capacitor C3 is grounded.

[0077] The third resistor R3 and the third capacitor C3 form an RC filter circuit, and the detection signal with the first level and the detection signal with the second level are filtered through the third resistor R3 and the third capacitor C3.

[0078] 5 , a first end of the fourth resistor R4 is coupled to a first end of the third capacitor C3 , a second end of the fourth resistor R4 is coupled to a first end of the fifth resistor R5 , and a second end of the fifth resistor R5 is grounded.

[0079] During implementation, the fourth resistor R4 and the fifth resistor R5 perform current limiting processing on the detection signal with the first level and the detection signal with the second level, so as to output them through the switch tube.

[0080] Based on the same inventive concept, an overcurrent protection circuit provided in an embodiment of the present application includes the above-mentioned current detection circuit and current protection circuit.

[0081] The current detection circuit is configured to output a detection signal having a first level.

[0082] During implementation, when the current detection circuit detects that the sampled voltage is greater than the reference voltage, it generates a detection signal with a first level. In this case, it means that the sampled voltage of the load is too large, which may affect the loop where the secondary winding is located.

[0083] The current protection circuit performs current protection on the loop where the secondary winding is located in response to a detection signal with a first level.

[0084] In order to effectively protect the circuit where the secondary winding is located, after determining that the current detection circuit has detected a detection signal with a first level, the current protection circuit performs current protection on the circuit where the secondary winding is located. Specific current protection measures include but are not limited to cutting off the circuit where the secondary winding is located, generating an overcurrent alarm, etc.

[0085] Based on the same inventive concept, an embodiment of the present application provides a display device, including the above-mentioned overcurrent protection circuit.

[0086] The display device provided in the embodiments of the present application can be any product or component with a display function, such as a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, or a navigation system. Other essential components of the display device are well understood by those skilled in the art and are not described here in detail, nor should they be construed as limitations of the present application.

[0087] Referring to FIG. 6 , based on the same inventive concept, an embodiment of the present application provides a current detection method, including:

[0088] Step 201 : The current sampling sub-circuit 10 generates a sampling voltage according to the current flowing through the voltage divider resistor coupled to the secondary winding.

[0089] In the embodiment of the present application, the current sampling sub-circuit 10 directly samples the current on the voltage divider resistor in the loop where the secondary winding is located, thereby generating a sampling voltage. Compared with current sampling in the loop where the primary winding is located, the above-mentioned sampling voltage is more accurate.

[0090] Step 202 : The voltage comparison sub-circuit 20 outputs a detection signal with a first level in response to the sampled voltage being greater than the reference voltage; and outputs a detection signal with a second level in response to the sampled voltage being less than the reference voltage.

[0091] It should be noted that in the embodiment of the present application, the reference voltage is directly generated based on the power supply voltage and the voltage conversion chip, thereby avoiding the influence of load fluctuations. During implementation, the voltage comparison subcircuit 20 compares the sampled voltage with the reference voltage and outputs a detection signal having a first level when the sampled voltage is greater than the reference voltage, and outputs a detection signal having a second level when the sampled voltage is less than the reference voltage.

[0092] In summary, in an embodiment of the present application, a current detection circuit, an overcurrent protection circuit, and a display device are provided. The current detection circuit includes: a current sampling subcircuit and a voltage comparison subcircuit. The current sampling subcircuit is coupled to the negative input terminal of the load, and the negative input terminal is coupled to the ground terminal and the secondary winding through a voltage divider resistor. The current sampling subcircuit is configured to generate a sampling voltage based on the current flowing through the voltage divider resistor. The voltage comparison subcircuit is coupled to the current sampling subcircuit and is configured to receive the sampling voltage. In response to the sampling voltage being greater than a reference voltage, the voltage comparison subcircuit outputs a detection signal with a first level, and in response to the sampling voltage being less than the reference voltage, the voltage comparison subcircuit outputs a detection signal with a second level. The above-mentioned current sampling subcircuit can directly collect the sampling voltage of the loop where the secondary winding is located, and then compare the sampling voltage with the reference voltage, so as to more accurately determine whether the current in the loop where the secondary winding is located is too large.

[0093] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program product systems. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product system implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0094] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program product systems according to the present application. It should be understood that each flow and / or box in the flow chart and / or block diagram, as well as the combination of the flow chart and / or box in the flow chart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more flow charts and / or one or more boxes in the block diagram.

[0095] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0096] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0097] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A current detection circuit, in, include: A current sampling subcircuit and a voltage comparison subcircuit; The current sampling subcircuit is coupled to the negative input terminal of the load, the negative input terminal is coupled to the ground terminal and the secondary winding through a voltage-dividing resistor, and is configured to generate a sampling voltage according to the current flowing through the voltage-dividing resistor; The voltage comparison subcircuit is coupled to the current sampling subcircuit and is configured to receive the sampled voltage; In response to the sampling voltage being greater than the reference voltage, outputting a detection signal having a first level; And, in response to the sampling voltage being less than the reference voltage, a detection signal having a second level is output.

2. The circuit as claimed in claim 1, in, Also included is a reference generation subcircuit, the reference generation subcircuit coupled to the voltage comparison subcircuit; The reference generation subcircuit is configured to perform voltage conversion on the power supply voltage to obtain the reference voltage, and output the reference voltage to the voltage comparison subcircuit.

3. The circuit as claimed in claim 2, in, The reference generation subcircuit comprises: a voltage conversion chip, a first capacitor and a second capacitor; The input end of the voltage conversion chip is used to receive the power supply voltage, and the output end of the voltage conversion chip is coupled to the voltage comparison subcircuit and is configured to perform voltage conversion on the power supply voltage to obtain the reference voltage; A first end of the first capacitor is coupled to an input end of the voltage conversion chip, and a second end of the first capacitor is grounded; A first end of the second capacitor is coupled to the output end of the voltage conversion chip, and a second end of the second capacitor is grounded.

4. The circuit as claimed in claim 1, in, The current sampling subcircuit comprises: an operational amplifier, a first resistor and a second resistor; The non-inverting input terminal of the operational amplifier is coupled to the negative input terminal; The inverting input terminal of the operational amplifier is grounded through the first resistor; The first end of the first resistor is grounded, and the second end of the first resistor is connected to the inverting input end coupling; The first end of the second resistor is coupled to the second end of the first resistor, and the second end of the second resistor is coupled to the output end of the operational amplifier.

5. The circuit as claimed in claim 4, in, The voltage comparison subcircuit includes a comparison module and an output module coupled to each other; The comparison module is configured to compare the received sample voltage with the reference voltage; The output module is configured to output a detection signal having the first level, or to output a detection signal having the second level.

6. The circuit as claimed in claim 5, in, The comparison module comprises: a comparator, wherein a positive input terminal of the comparator is coupled to an output terminal of the operational amplifier, a negative input terminal of the comparator is coupled to an output terminal of the reference generation subcircuit, and an output terminal of the comparator is coupled to the output module; The output module includes: a switch tube, a control end of the switch tube is coupled to the output end of the comparator, a first electrode of the switch tube is coupled to a pull-up resistor, and a second electrode of the switch tube is grounded.

7. The circuit as claimed in claim 5, in, The voltage comparison subcircuit further includes: a third resistor, a third capacitor, a fourth resistor and a fifth resistor; The first end of the third resistor is coupled to the power supply voltage receiving end of the comparator, the second end of the third resistor is coupled to the first end of the third capacitor, and the second end of the third capacitor is grounded; A first end of the fourth resistor is coupled to a first end of the third capacitor, a second end of the fourth resistor is coupled to a first end of the fifth resistor, and a second end of the fifth resistor is grounded.

8. An overcurrent protection circuit, in, include: The current detection circuit and the current protection circuit according to any one of claims 1 to 7; The current detection circuit is used to output a detection signal having the first level; The current protection circuit performs current protection on the loop where the secondary winding is located in response to the detection signal with the first level.

9. A display device, in, include: The overcurrent protection circuit as claimed in claim 8.

10. A current detection method, in, include: The current sampling subcircuit generates a sampling voltage according to the current flowing through the voltage dividing resistor coupled to the secondary winding; The voltage comparison subcircuit outputs a detection signal having a first level in response to the sampling voltage being greater than the reference voltage; And, in response to the sampling voltage being less than the reference voltage, a detection signal having a second level is output.

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