Short circuit protection circuit, array substrate, display device and short circuit protection method

Abstract

The invention discloses a short-circuit protection circuit, an array substrate, a display device and a short-circuit protection method, and relates to the technical field of display. The disclosed short-circuit protection circuit comprises a short-circuit detection module and a short-circuit processing module; the short circuit detection module converts the current loop current on the OLED device into a target detection voltage and outputs the target detection voltage to the short circuit processing module; the short circuit processing module compares the target detection voltage with a preset reference voltage; the short circuit processing module judges that the OLED device is in a short circuit state when the target detection voltage is greater than the preset reference voltage; and when the OLED device is in a short-circuit state, the short-circuit processing module disconnects the loop where the OLED device is located in the OLED driving module. According to the invention, accurate detection of the short circuit of the OLED device is realized through a voltage comparison mode, so that the OLED device can be timely disconnected when the OLED device is short-circuited, and the potential safety hazard is effectively reduced.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a short-circuit protection circuit, an array substrate, a display device and a short-circuit protection method. Background Art

[0002] Compared with liquid crystal displays (LCD), organic light-emitting diodes (OLEDs) have smaller size, thinner screens, and higher contrast, and have become the current development trend.

[0003] Due to limitations in industrial processes and other aspects, OLED devices in display devices are inevitably doped with foreign matter during preparation. During operation, these foreign matter may cause a short circuit and burn the OLED device and the peripheral connected devices of the OLED. At present, in order to avoid the above problems, a fuse-type short-circuit protection design is adopted, and a fuse device is added to the OLED drive circuit. When the current flowing through the OLED device reaches the current when the fuse device is blown, the OLED device is judged to be short-circuited, and the fuse device is triggered to blow, thereby disconnecting the OLED drive circuit and achieving protection for the display device.

[0004] However, when the display device is actually operating, the short-circuit current when a short circuit occurs is generally not large, and is lower than the current required for the fuse device to blow, resulting in an inability to accurately detect whether the OLED device is short-circuited, and then unable to trigger the fuse to blow in time to disconnect the OLED device when a short circuit occurs, posing a safety hazard.

[0005] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0006] The main purpose of the present application is to provide a short-circuit protection circuit, an array substrate, a display device and a short-circuit protection method, aiming to solve the technical problem that the prior art cannot accurately detect whether an OLED device is short-circuited, and thus cannot trigger the fuse to blow in time to disconnect the OLED device when a short circuit occurs, resulting in a safety hazard.

[0007] To achieve the above object, the present application provides a short circuit protection circuit, the short circuit protection circuit comprising: a short circuit detection module and a short circuit processing module;

[0008] The short circuit detection module is connected to the short circuit processing module and the OLED device in the OLED driving module respectively, and the short circuit processing module is connected to the OLED driving module;

[0009] The short circuit detection module is used to convert the current loop current on the OLED device into a target detection voltage and then output it to the short circuit processing module;

[0010] The short circuit processing module is used to compare the target detection voltage with a preset reference voltage;

[0011] The short-circuit processing module is further used to determine that the OLED device is in a short-circuit state when the target detection voltage is greater than the preset reference voltage;

[0012] The short-circuit processing module is further used to disconnect the circuit where the OLED device is located in the OLED driving module when the OLED device is in the short-circuit state.

[0013] In one embodiment, the short circuit detection module includes: a current detection unit and a voltage amplification unit;

[0014] The current detection unit is connected to the voltage amplification unit and the OLED device in the OLED driving module respectively, and the voltage amplification unit is connected to the short-circuit processing module;

[0015] The current detection unit is used to detect the current loop current on the OLED device, and convert the current loop current into an initial loop voltage and then output it to the voltage amplification unit;

[0016] The voltage amplification unit is used to amplify the initial loop voltage to obtain the target loop voltage;

[0017] The voltage amplifying unit is further used to perform analog-to-digital conversion on the target loop voltage to obtain the target detection voltage in the form of a digital signal, and output the target detection voltage to the short-circuit processing module.

[0018] In one embodiment, the current detection unit includes: a first MOS tube and a current detection resistor;

[0019] The drain of the first MOS tube is connected to the anode of the OLED device, the source of the first MOS tube is respectively connected to the first end of the current detection resistor and the voltage amplification unit, and the second end of the current detection resistor is grounded.

[0020] In one embodiment, the voltage amplification module includes: a first operational amplifier, a first resistor, a second resistor, a third resistor, and an analog-to-digital converter;

[0021] The inverting input terminal of the first operational amplifier is respectively connected to the first end of the first resistor and the first end of the second resistor, the second end of the first resistor is grounded, the second end of the second resistor is respectively connected to the output terminal of the first operational amplifier and the input terminal of the analog-to-digital converter, and the output terminal of the analog-to-digital converter is connected to the short-circuit processing module;

[0022] The non-inverting input terminal of the first operational amplifier is connected to the first terminal of the third resistor, and the second terminal of the third resistor is respectively connected to the source of the first MOS tube and the first terminal of the current detection resistor.

[0023] In one embodiment, the short circuit processing module includes: a voltage comparator and a short circuit processing driving tube;

[0024] The non-inverting input terminal of the voltage comparator is connected to the comparator reference source, the inverting input terminal of the voltage comparator is connected to the voltage amplification module, the output terminal of the voltage comparator is connected to the gate of the short-circuit processing driving tube, the drain of the short-circuit processing driving tube is connected to the power supply terminal in the OLED driving module, and the source of the short-circuit processing driving tube is connected to the anode of the OLED device;

[0025] The voltage comparator is used to compare the target detection voltage with the preset reference voltage input by the comparator reference source;

[0026] The voltage comparator is also used to control the on-off state of the short-circuit processing driving tube according to the voltage comparison result.

[0027] In one embodiment, the voltage comparator is further used to output a low-level driving signal to the short-circuit processing driving tube when the target detection voltage is greater than the preset reference voltage, so that the short-circuit processing driving tube is in a disconnected state;

[0028] The short-circuit processing driving tube is used to disconnect the circuit between the OLED device and the power supply end when in the disconnected state.

[0029] In one embodiment, the voltage comparison unit is further used to output a high-level driving signal to the short-circuit processing driving tube when the target detection voltage is less than the preset reference voltage, so that the short-circuit processing driving tube is in a closed state;

[0030] The short-circuit processing driving tube is used to connect the circuit between the OLED device and the power supply end when in the closed state.

[0031] In addition, to achieve the above-mentioned purpose, the present application also proposes an array substrate, the array substrate comprising: an OLED driving module and the short-circuit protection circuit described above;

[0032] The OLED driving module includes: an OLED device, a scanning signal driving tube, an OLED device driving tube and a first capacitor;

[0033] The drain of the scanning signal driving tube is connected to the signal line, the source of the scanning signal driving tube is respectively connected to the gate of the OLED device driving tube and the first end of the first capacitor, and the second end of the first capacitor is respectively connected to the power supply end and the drain of the short-circuit processing driving tube in the short-circuit protection circuit;

[0034] The drain electrode of the OLED device driving tube is connected to the source electrode of the short-circuit processing driving tube, the source electrode of the OLED device driving tube is connected to the anode electrode of the OLED device, and the cathode electrode of the OLED device is grounded.

[0035] In addition, to achieve the above objectives, the present application also proposes a display device, which includes the array substrate described above.

[0036] In addition, to achieve the above object, the present application also proposes a short circuit protection method, which is applied to the short circuit protection circuit described above, and the method includes:

[0037] Convert the current loop current on the OLED device into a target detection voltage;

[0038] comparing the target detection voltage with a preset reference voltage;

[0039] When the target detection voltage is greater than the preset reference voltage, determining that the OLED device is in a short-circuit state;

[0040] When the OLED device is in the short-circuit state, the circuit in which the OLED device is located in the OLED driving module is disconnected.

[0041] One or more technical solutions proposed in this application have at least the following technical effects:

[0042] The short circuit protection circuit of the present application includes: a short circuit detection module and a short circuit processing module; the short circuit detection module is connected to the short circuit processing module and the OLED device in the OLED driving module respectively, and the short circuit processing module is connected to the OLED driving module; the short circuit detection module of the present application converts the current loop current on the OLED device into a target detection voltage and then outputs it to the short circuit processing module; the short circuit processing module compares the target detection voltage with a preset reference voltage; the short circuit processing module determines that the OLED device is in a short circuit state when the target detection voltage is greater than the preset reference voltage; the short circuit processing module disconnects the loop where the OLED device is located in the OLED driving module when the OLED device is in a short circuit state. Compared with the fuse-type short circuit protection method of the prior art, the present application converts the current loop current on the OLED device into a target detection voltage, and uses a voltage comparison method to compare the target detection voltage with the preset reference voltage. When the target detection voltage is greater than the preset reference voltage, it is determined that the OLED device is in a short circuit state, thereby realizing accurate detection of whether the OLED device is short-circuited, and then the OLED device can be disconnected in time when the OLED device is short-circuited, effectively reducing safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] 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.

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0045] Figure 1 This is a schematic diagram of the module structure of the first embodiment of the short-circuit protection circuit of the present application;

[0046] Figure 2 This is a schematic diagram of the module structure of the second embodiment of the short-circuit protection circuit of the present application;

[0047] Figure 3 A circuit schematic diagram of a second embodiment of the current protection circuit of the present application;

[0048] Figure 4 A circuit schematic diagram of a third embodiment of the short-circuit protection circuit of the present application;

[0049] Figure 5 This is a timing diagram of the third embodiment of the short-circuit protection circuit of the present application;

[0050] Figure 6 It is a flow chart of a short circuit protection method embodiment of the present invention.

[0051] Label:

[0052] Description of Figure Numbers:

[0053] 100. Short circuit detection module;

[0054] 101, current detection unit; T1, first MOS tube; Rs, current detection resistor;

[0055] 102, voltage amplification unit; A1, first operational amplifier; R1, first resistor; R2, second resistor; R3, third resistor;

[0056] 200, short circuit processing module; A2, voltage comparator; T2, short circuit processing driver; VH, high level signal; VL, low level signal; Vref1, comparator reference source; Vref2, initial reference source; 300, OLED driver module; D1, OLED device; T01, scan signal driver; T02, OLED device driver; C1, first capacitor; VDD, power supply terminal; Vdata, signal line;

[0057] Scan1, the first scanning signal; Scan2, the second scanning signal.

[0058] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0059] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0060] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0061] The main solution of the embodiment of the present application is: the short-circuit detection module converts the current loop current on the OLED device into a target detection voltage and outputs it to the short-circuit processing module; the short-circuit processing module compares the target detection voltage with a preset reference voltage; the short-circuit processing module determines that the OLED device is in a short-circuit state when the target detection voltage is greater than the preset reference voltage; the short-circuit processing module disconnects the loop of the OLED device in the OLED driving module when the OLED device is in a short-circuit state.

[0062] Due to the limitations of industrial processes and other aspects, the OLED devices in the display devices will inevitably be doped with foreign matter during preparation. During operation, these foreign matter will cause a short circuit phenomenon and burn the OLED device and the peripheral connected devices of the OLED. For example, for the traditional 2T1C OLED overall display module, the power supply end and the VCOM (common voltage) end of the OLED device share a signal line. When an OLED device is short-circuited, the large current will affect other peripheral devices, causing display abnormalities, and in severe cases, it will cause in-plane burns and cause fires and other safety accidents. In order to solve the above problems, the prior art adopts a fuse-type short-circuit protection design, adding a fuse device to the OLED drive circuit. When the current flowing through the OLED device reaches the current when the fuse device is blown, the OLED device is judged to be short-circuited, and the fuse device is triggered to blow, thereby disconnecting the OLED drive circuit and realizing the protection of the display device. However, when the display device is actually running, the short-circuit current when a short circuit occurs is generally not large, and is lower than the current required when the fuse device is blown, resulting in the inability to accurately detect whether the OLED device is short-circuited, and then the fuse cannot be triggered to blow in time to disconnect the OLED device when a short circuit occurs, which poses a safety hazard.

[0063] The present application provides a solution, by converting the current loop current on the OLED device into a target detection voltage, and using a voltage comparison method to compare the target detection voltage with a preset reference voltage, when the target detection voltage is greater than the preset reference voltage, the OLED device is determined to be in a short-circuit state, thereby achieving accurate detection of whether the OLED device is short-circuited, and then being able to disconnect the OLED device in time when a short circuit occurs in the OLED device, effectively reducing safety hazards.

[0064] Based on this, the embodiment of the present application provides a short circuit protection circuit, referring to Figure 1 , Figure 1 This is a schematic diagram of the module structure of the first embodiment of the short-circuit protection circuit of the present application.

[0065] In this embodiment, the short circuit protection circuit includes: a short circuit detection module 100 and a short circuit processing module 200 .

[0066] The short circuit detection module 100 is connected to the short circuit processing module 200 and the OLED device D1 in the OLED driving module 300 respectively, and the short circuit processing module 100 is connected to the OLED driving module 300 .

[0067] It should be noted that the OLED driving module 300 may be the OLED driving circuit described above. Figure 1 As shown, the OLED driving module 300 includes: an OLED device D1, a scan signal driving tube T01, an OLED device driving tube T02 and a first capacitor C1;

[0068] The drain of the scan signal driving tube T01 is connected to the signal line Vdata, the source of the scan signal driving tube T01 is respectively connected to the gate of the OLED device driving tube T02 and the first end of the first capacitor C1, and the second end of the first capacitor C1 is respectively connected to the power supply end VDD and the first end of the short circuit processing module 200.

[0069] The drain of the OLED device driving tube T02 is connected to the second end of the short circuit processing module, the source of the OLED device driving tube T02 is connected to the anode of the OLED device D1, and the cathode of the OLED device D1 is grounded.

[0070] It should be noted that this embodiment and the following embodiments are all described with N-type driving MOS tubes for the scanning signal driving tube T01 and the OLED device driving tube T02, but this embodiment is not limited thereto. When the first scanning signal Scan1 output by the scanning line received by the gate of the scanning signal driving tube T01 is at a high level, it is turned on, and the high level signal of the data line Vdata is output to the gate of the OLED device driving tube T02, so that the OLED device driving tube T02 is turned on, and the OLED device D1 is connected to the power supply terminal VDD to achieve lighting.

[0071] It is understandable that the ground terminal of the cathode of the above-mentioned OLED device D1 can be the VCOM terminal, and the power supply terminal VDD and the VCOM terminal of the OLED driving module 300 share a signal line drive. Therefore, when the OLED device D1 is short-circuited, the large current will affect other peripheral devices, causing display abnormalities and posing a safety hazard.

[0072] The short circuit detection module 100 is used to convert the current loop current on the OLED device D1 into a target detection voltage and then output it to the short circuit processing module 200 .

[0073] It should be noted that, since the short-circuit current when the display device is actually running is generally not large, the above-mentioned short-circuit detection module 100 can detect the current loop current on the OLED device D1 in real time, that is, the current output from the power supply terminal VDD to the OLED device, and then convert the detected current loop current into a voltage, and convert the voltage into a target detection voltage of a digital signal type. The target detection voltage is used to detect whether the OLED device D1 is short-circuited, thereby avoiding the situation where the current loop current is small during a short circuit and it is impossible to accurately determine whether the OLED device D1 is short-circuited.

[0074] The short circuit processing module 200 is used to compare the target detection voltage with a preset reference voltage.

[0075] The short-circuit processing module 200 is further configured to determine that the OLED device D1 is in a short-circuit state when the target detection voltage is greater than the preset reference voltage.

[0076] It should be noted that the preset reference voltage may be a relatively large voltage value, and an upper threshold value for determining that the OLED device D1 is in a short-circuit state.

[0077] In a specific implementation, the short-circuit processing module 200 can compare the target detection voltage fed back by the short-circuit detection module 100 with a preset reference voltage to determine whether the target detection voltage is greater than the preset reference voltage. When the target detection voltage is greater than the preset reference voltage, it can be determined that the target detection voltage is large and the OLED device D1 is in a short-circuit state. On the contrary, when the target detection voltage is less than the preset reference voltage, it can be determined that the target detection voltage is small and the OLED device D1 is not in a short-circuit state, thereby achieving accurate detection of whether the OLED device D1 is short-circuited.

[0078] The short-circuit processing module 200 is further used to disconnect the circuit where the OLED device D1 is located in the OLED driving module 300 when the OLED device D1 is in the short-circuit state.

[0079] It should be noted that the short circuit processing module may be provided with a switch device, such as Figure 1 As shown, the switch device can be arranged between the power supply terminal VDD and the OLED device driving tube T02 in the OLED driving module 300. In addition, the switch device can also be arranged between the OLED device driving tube T02 and the OLED device D1. This embodiment and the following embodiments are all described as the switch device being between the power supply terminal VDD and the OLED device driving tube T02, but this solution is not limited.

[0080] In a specific implementation, when the short-circuit processing module 200 detects that the OLED device D1 is in a short-circuit state, it can output a level driving signal to the control end of the switch device to control the switch device to be disconnected, thereby disconnecting the connection between the OLED device D1 and the power supply end VDD, thereby accurately disconnecting the loop where the OLED device D1 is located in the OLED driving module 300 to achieve short-circuit protection.

[0081] In addition, at the startup time of the OLED driving module 300, the control end of the switching device can be connected to a reference source, and the reference source can output a control signal to close the switching device. After the switching device is turned on, the control end of the switching device can be switched to the short-circuit processing module 200 to avoid the situation where the switching device cannot be turned on at the startup time, so that the driving circuit of the OLED device D1 cannot be connected, thereby ensuring that the OLED device D1 lights up normally.

[0082] The short circuit protection circuit of the present embodiment includes: a short circuit detection module and a short circuit processing module; the short circuit detection module is connected to the short circuit processing module and the OLED device in the OLED driving module respectively, and the short circuit processing module is connected to the OLED driving module; the short circuit detection module of the present embodiment converts the current loop current on the OLED device into a target detection voltage and then outputs it to the short circuit processing module; the short circuit processing module compares the target detection voltage with a preset reference voltage; the short circuit processing module determines that the OLED device is in a short circuit state when the target detection voltage is greater than the preset reference voltage; the short circuit processing module disconnects the loop where the OLED device is located in the OLED driving module when the OLED device is in a short circuit state. Compared with the fuse-type short circuit protection method of the prior art, the present embodiment converts the current loop current on the OLED device into a target detection voltage, and compares the target detection voltage with the preset reference voltage by a voltage comparison method. When the target detection voltage is greater than the preset reference voltage, it is determined that the OLED device is in a short circuit state, thereby realizing accurate detection of whether the OLED device is short-circuited, and then the OLED device can be disconnected in time when the OLED device is short-circuited, effectively reducing safety hazards.

[0083] Based on the first embodiment of the present application, a second embodiment of the short-circuit protection circuit of the present application is proposed. In the second embodiment of the present application, the same or similar contents as those of the first embodiment can be referred to the above introduction and will not be described in detail later. Figure 2 , Figure 2 This is a schematic diagram of the module structure of the second embodiment of the short-circuit protection circuit of the present application.

[0084] In this embodiment, the short circuit detection module 100 includes a current detection unit 101 and a voltage amplification unit 102 .

[0085] The current detection unit 101 is connected to the voltage amplification unit 102 and the OLED device D1 in the OLED driving module respectively, and the voltage amplification unit 102 is connected to the short circuit processing module 200 .

[0086] The current detection unit 101 is used to detect the current loop current on the OLED device D1 , and convert the current loop current into an initial loop voltage and output it to the voltage amplification unit 102 .

[0087] It should be noted that the current detection unit 101 can detect the current loop current on the OLED device D1 and then convert the current loop current into an initial loop voltage through a resistor. Figure 3 As shown, Figure 3 This is a circuit diagram of the second embodiment of the current protection circuit of the present application. Figure 3In the embodiment, the current detection unit 101 includes a first MOS transistor T1 and a current detection resistor Rs.

[0088] The drain of the first MOS transistor T1 is connected to the anode of the OLED device D1 , the source of the first MOS transistor T1 is respectively connected to the first end of the current detection resistor Rs and the voltage amplifying unit 102 , and the second end of the current detection resistor Rs is grounded.

[0089] In the specific implementation, this embodiment and the following embodiments are all described with an N-type driving MOS tube for the first MOS tube T1, but this embodiment is not limited. The gate of the above-mentioned first MOS tube T1 can be connected to the scan line. When the second scan signal Scan2 output by the scan line is at a high level, the first MOS tube T1 is closed to detect the current loop current on the OLED device D1. The initial loop voltage can be obtained by dividing the current detection resistor Rs. The value of the initial loop voltage can be the product of the value of the current loop current and the resistance value of the current detection resistor Rs.

[0090] The voltage amplifying unit 102 is used to amplify the initial loop voltage to obtain the target loop voltage.

[0091] The voltage amplifying unit 102 is further used to perform analog-to-digital conversion on the target loop voltage to obtain the target detection voltage in the form of a digital signal, and output the target detection voltage to the short circuit processing module 200 .

[0092] It should be noted that when a short circuit occurs, the short circuit current is small, and the converted voltage is also small, so it is impossible to accurately detect whether the OLED device D1 is short-circuited. Therefore, the voltage amplification unit 102 can amplify the initial loop voltage output by the current detection unit 101 to obtain the target loop voltage, and then perform analog-to-digital conversion after obtaining the target loop voltage, converting the analog signal type target loop voltage into a numerical signal type target detection voltage, and then outputting the target detection voltage to the short circuit processing module, so as to compare the amplified target detection voltage with the preset reference voltage to improve the accuracy of short circuit detection.

[0093] like Figure 3 As shown, the voltage amplification module includes: a first operational amplifier A1, a first resistor R1, a second resistor R2, a third resistor R3 and an analog-to-digital converter ADC;

[0094] The inverting input terminal of the first operational amplifier A1 is respectively connected to the first end of the first resistor R1 and the first end of the second resistor R2, the second end of the first resistor R1 is grounded, the second end of the second resistor R2 is respectively connected to the output terminal of the first operational amplifier A1 and the input terminal of the analog-to-digital converter ADC, and the output terminal of the analog-to-digital converter ADC is connected to the short-circuit processing module 200.

[0095] The non-inverting input terminal of the first operational amplifier A1 is connected to the first end of the third resistor R3 , and the second end of the third resistor R3 is respectively connected to the source of the first MOS transistor T1 and the first end of the current detection resistor Rs.

[0096] In a specific implementation, the third resistor R3 can be an isolation resistor to prevent the voltage input to the first operational amplifier A1 from being too large. The non-inverting input terminal of the first operational amplifier A1 receives the initial loop voltage, and amplifies the initial loop voltage through the first resistor R1 and the second resistor R2 to obtain a target loop voltage, wherein the target loop voltage output by the first operational amplifier A1 is determined by the following formula:

[0097]

[0098] Wherein, VB is the target loop voltage, VA is the initial loop voltage, r1 is the resistance value of the first resistor R1, and r2 is the resistance value of the second resistor R2.

[0099] In addition, the resistance of the second resistor R2 is adjustable so as to adjust the amplification gain of the first operational amplifier according to requirements.

[0100] It should be understood that the target loop voltage output by the first operational amplifier can be input to an analog-to-digital converter ADC, which converts the target loop voltage into a target detection voltage of a digital signal type and then outputs it to the short circuit processing module.

[0101] The current detection unit of this embodiment detects the current loop current on the OLED device, and converts the current loop current into an initial loop voltage and then outputs it to the voltage amplification unit; the voltage amplification unit amplifies the initial loop voltage to obtain a target loop voltage; the voltage amplification unit performs analog-to-digital conversion on the target loop voltage to obtain the target detection voltage of the digital signal type, and outputs the target detection voltage to the short-circuit processing module. Since this embodiment amplifies the initial loop voltage after converting the current loop current into the initial loop voltage, it can avoid the situation where the amplitude of the obtained target detection voltage is too small and it is impossible to accurately detect whether the OLED device D1 is short-circuited, thereby further improving the accuracy of short-circuit detection.

[0102] Based on the first and second embodiments of the present application, a third embodiment of the short-circuit protection circuit of the present application is proposed. In the third embodiment of the present application, the same or similar contents as those of the first and second embodiments can be referred to the above description and will not be described in detail later. Figure 4 , Figure 4 This is a circuit schematic diagram of the third embodiment of the short-circuit protection circuit of the present application.

[0103] In this embodiment, the short circuit processing module 200 includes: a voltage comparator A2 and a short circuit processing driving tube T2.

[0104] The non-inverting input terminal of the voltage comparator A2 is connected to the comparator reference source Vref1, the inverting input terminal of the voltage comparator A2 is connected to the voltage amplification module 102, the output terminal of the voltage comparator A2 is connected to the gate of the short-circuit processing driving tube T2, the drain of the short-circuit processing driving tube T2 is connected to the power supply terminal in the OLED driving module D1, and the source of the short-circuit processing driving tube T2 is connected to the anode of the OLED device D1.

[0105] The voltage comparator A2 is used to compare the target detection voltage with the preset reference voltage input from the comparator reference source Vref1.

[0106] In a specific implementation, the inverting input terminal of the voltage comparator A2 is connected to the analog-to-digital converter ADC in the voltage amplification module 102 to receive the target detection voltage output by the analog-to-digital converter ADC. The inverting input terminal of the voltage comparator A2 is connected to the comparator reference source Vref1 to receive the preset reference voltage output by the comparator reference source Vref1. Then, the target detection voltage is compared with the preset reference voltage to determine whether the voltage caused by the target is greater than the preset reference voltage, thereby detecting whether the OLED device D1 is in a short-circuit state.

[0107] The voltage comparator A2 is also used to control the on / off state of the short-circuit processing driving tube T2 according to the voltage comparison result.

[0108] In a specific implementation, the voltage comparator A2 can output a high-level driving signal VH or a low-level driving signal VL to the short-circuit processing driving tube according to the voltage comparison result, so as to control the on-off state of the short-circuit processing driving tube T2.

[0109] In addition, this embodiment and the following embodiments are all described with an N-type driving MOS tube for the short-circuit processing driving tube T2, but this embodiment is not limited. The gate of the short-circuit processing driving tube T2 is connected to the initial reference source Vref2 at the initial moment when the OLED driving module 300 is powered on, and the initial reference source Vref2 outputs a high-level signal to control the short-circuit processing driving tube T2 to close at the initial moment, ensuring that the OLED driving module 300 is turned on at the initial moment, and the OLED device D1 is normally lit. After the short-circuit processing driving tube T2 is closed, the gate of the short-circuit processing driving tube T2 is switched to the output end of the voltage comparator A2. Among them, the gate switching of the short-circuit processing driving tube T2 can be realized by a relay. For example, when the coil is energized, the mechanical switch of the relay will switch from one port to another port.

[0110] The short-circuit processing driving tube T2 can be as follows: Figure 4 As shown in , it is located between the power supply terminal VDD and the OLED device driving tube T02, and can also be located between the OLED device driving tube T02 and the OLED device D1, which is not limited in this embodiment.

[0111] Furthermore, in this embodiment, the voltage comparator A2 is also used to output a low-level driving signal VL to the short-circuit processing driving tube T2 when the target detection voltage is greater than the preset reference voltage, so as to put the short-circuit processing driving tube T2 in a disconnected state.

[0112] The short-circuit processing driving tube A2 is used to disconnect the circuit between the OLED device D1 and the power supply terminal VDD when in the disconnected state.

[0113] In a specific implementation, when the voltage comparator A2 detects that the target detection voltage is greater than the preset reference voltage, since the OLED device D1 is in a short-circuit state at this time, it can output a low-level drive signal VL to the short-circuit processing driver tube T2, so that the short-circuit processing driver tube T2 is disconnected, and the loop between the power supply terminal VDD and the OLED device D1 is disconnected, thereby achieving short-circuit protection.

[0114] Furthermore, in this embodiment, the voltage comparison unit A2 is also used to output a high-level driving signal VH to the short-circuit processing driving tube T2 when the target detection voltage is less than the preset reference voltage, so as to put the short-circuit processing driving tube T2 in a closed state.

[0115] The short-circuit processing driving tube T2 is used to connect the loop between the OLED device D1 and the power supply terminal VDD when in the closed state.

[0116] In a specific implementation, when the voltage comparator A2 detects that the target detection voltage is less than the preset reference voltage, since the OLED device D1 is not in a short-circuit state at this time, it can output a high-level drive signal VH to the short-circuit processing drive tube T2, so that the short-circuit processing drive tube T2 is closed, and the loop between the power supply terminal VDD and the OLED device D1 is kept conductive.

[0117] For ease of understanding, refer to Figure 5 This is for illustration only, but does not limit this solution. Figure 5 This is a timing diagram of the third embodiment of the short-circuit protection circuit of the present application. Figure 5 In the embodiment, at the beginning of the first frame Frame1, the gate of the short-circuit processing driving tube T2 is connected to the initial reference source Vref2, and the voltage output by the initial reference source Vref2 can turn on the short-circuit processing driving tube T2. The first scanning signal Scan1 of the scanning signal driving tube T01 and the second scanning signal Scan1 of the OLED device driving tube T02 are both high level, the scanning signal driving tube T01 and the OLED device driving tube T02 are turned on, and the data line Vdata outputs a high level signal to the gate of the OLED device driving tube T02 through the scanning signal driving tube T01, and the OLED device driving tube T02 is also turned on, thereby driving the OLED device D1, and the short-circuit detection module 100 starts to detect the current loop current on the OLED device D1.

[0118] When the OLED device D1 works normally without short circuit, the target detection voltage VC output by the analog-to-digital converter ADC is less than the preset reference voltage output by the comparator reference source Vref1, and the output signal VD of the voltage comparator A2 is a high-level signal VH. Since the short-circuit processing driving tube T2 is connected to the output end of the voltage comparator A2, the gate G of the short-circuit processing driving tube T2 is at a high level, the short-circuit processing driving tube T2 is turned on, and the entire OLED driving module 300 works normally. When the OLED device D1 is short-circuited, the current loop current increases, the initial loop voltage VA and the target loop voltage VB rise, so that the target detection voltage VC output by the ADC is greater than the preset reference voltage output by the comparator reference source Vref1 (that is, VD-Vref1 in the figure is at a high level when short-circuited), and the output signal VD of the voltage comparator A2 is a low-level signal VL. At this time, the gate G of the short-circuit processing driving tube T2 is at a low level, the short-circuit processing driving tube T2 is turned off, and no voltage or current flows through the OLED device D1, which will not cause display abnormalities of other diodes. The short circuit detection process of the second frame Frame2 may refer to the description of the first frame Frame1, which will not be described again here.

[0119] In this embodiment, the voltage comparator compares the target detection voltage with the preset reference voltage input by the comparator reference source. When the target detection voltage is greater than the preset reference voltage, a low-level driving signal is output to the short-circuit processing driving tube, so that the short-circuit processing driving tube is in an off state, and the loop between the OLED device and the power supply end is disconnected; when the target detection voltage is less than the preset reference voltage, a high-level driving signal is output to the short-circuit processing driving tube, so that the short-circuit processing driving tube is in a closed state, and the loop between the OLED device and the power supply end is connected, thereby achieving accurate disconnection of the OLED device when the OLED device is short-circuited, without causing display abnormalities of other diodes, and effectively reducing safety hazards.

[0120] The present application also provides an array substrate, referring to Figure 4 , the array substrate comprises: an OLED driving module 300 and the short-circuit protection circuit according to any one of claims 1 to 6.

[0121] The OLED driving module 300 includes: an OLED device D1, a scan signal driving tube T01, an OLED device driving tube T02 and a first capacitor C1.

[0122] The drain of the scan signal driving tube T01 is connected to the signal line Vdata, the source of the scan signal driving tube T01 is respectively connected to the gate of the OLED device driving tube T02 and the first end of the first capacitor C1, the second end of the first capacitor C1 is respectively connected to the power supply terminal VDD and the drain of the short-circuit processing driving tube T1 in the short-circuit protection circuit; the drain of the OLED device driving tube T02 is connected to the source of the short-circuit processing driving tube T1, the source of the OLED device driving tube T02 is connected to the anode of the OLED device D1, and the cathode of the OLED device D1 is grounded.

[0123] The array substrate provided by the present application includes the short-circuit protection circuit in the above-mentioned embodiment, which can solve the technical problem that the prior art cannot accurately detect whether the OLED device is short-circuited, and thus cannot trigger the fuse to blow in time to disconnect the OLED device when the short circuit occurs, which poses a potential safety hazard. Compared with the prior art, the beneficial effects of the array substrate provided by the present application are the same as the beneficial effects of the short-circuit protection circuit provided by the above-mentioned embodiment, and other technical features of the short-circuit protection circuit of the array substrate are the same as the features disclosed in the short-circuit protection circuit in the above-mentioned embodiment, which will not be described in detail here.

[0124] The present application also provides a display device, which includes the array substrate described above.

[0125] The display device provided in the present application includes the array substrate described above. The beneficial effects of the display device of the present application are the same as the beneficial effects of the above-mentioned array substrate, and other technical features of the display device are the same as the features disclosed in the above-mentioned array substrate, which will not be repeated here.

[0126] The present application also proposes a short circuit protection method, which is applied to the short circuit protection circuit described in the above embodiment. Figure 6 , Figure 6 It is a flow chart of a short circuit protection method embodiment of the present invention.

[0127] like Figure 6 As shown, in this embodiment, the short circuit protection method includes steps S10 to S40:

[0128] Step S10, converting the current loop current on the OLED device into a target detection voltage.

[0129] It should be noted that the execution subject of the above short-circuit protection method can be executed by a short-circuit protection device equipped with the above short-circuit protection short-circuit.

[0130] In a specific implementation, the above-mentioned short-circuit protection device can detect the current loop current on the OLED device in real time, and then convert the detected current loop current into a voltage, and convert the voltage into a target detection voltage of a digital signal type, and use the target detection voltage to detect whether the OLED device is short-circuited, thereby avoiding the situation where the current loop current is too small during a short circuit to accurately determine whether the OLED device is short-circuited.

[0131] In step S20, the target detection voltage is compared with a preset reference voltage.

[0132] Step S30 , when the target detection voltage is greater than the preset reference voltage, determining that the OLED device is in a short-circuit state.

[0133] In a specific implementation, the short-circuit protection device can compare the target detection voltage with the preset reference voltage to determine whether the target detection voltage is greater than the preset reference voltage. When the target detection voltage is greater than the preset reference voltage, it can be determined that the target detection voltage is large and the OLED device is in a short-circuit state. On the contrary, when the target detection voltage is less than the preset reference voltage, it can be determined that the target detection voltage is small and the OLED device is not in a short-circuit state, thereby achieving accurate detection of whether the OLED device is short-circuited.

[0134] Step S40, when the OLED device is in the short-circuit state, disconnecting the circuit of the OLED device in the OLED driving module.

[0135] In a specific implementation, when the short-circuit protection device detects that the OLED device is in a short-circuit state, it can output a level driving signal to the control end of the switch device (which can be the short-circuit processing driving tube in the above embodiment) in the short-circuit protection circuit, and control the switch device to be disconnected, thereby disconnecting the connection between the OLED device and the power supply terminal VDD, thereby accurately disconnecting the loop where the OLED device is located in the OLED driving module, and realizing short-circuit protection.

[0136] The short-circuit protection method provided in this embodiment converts the current loop current on the OLED device into a target detection voltage and then outputs it to the short-circuit processing module; compares the target detection voltage with a preset reference voltage; when the target detection voltage is greater than the preset reference voltage, determines that the OLED device is in a short-circuit state; when the OLED device is in a short-circuit state, disconnects the loop where the OLED device is located in the OLED driving module. Compared with the fuse-type short-circuit protection method in the prior art, this embodiment converts the current loop current on the OLED device into a target detection voltage, and uses a voltage comparison method to compare the target detection voltage with a preset reference voltage. When the target detection voltage is greater than the preset reference voltage, it is determined that the OLED device is in a short-circuit state, thereby achieving accurate detection of whether the OLED device is short-circuited, and then the OLED device can be disconnected in time when a short circuit occurs in the OLED device, effectively reducing safety hazards.

[0137] Other embodiments or specific implementations of the stream data writing device of the present application can refer to the above-mentioned method embodiments and will not be repeated here.

[0138] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0139] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0140] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory / random access memory, a disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0141] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A short circuit protection circuit, It is characterized in that The circuit comprises: a short circuit detection module and a short circuit processing module; The short circuit detection module is connected to the short circuit processing module and the OLED device in the OLED driving module respectively, and the short circuit processing module is connected to the OLED driving module; The short circuit detection module is used to convert the current loop current on the OLED device into a target detection voltage and then output it to the short circuit processing module; The short circuit processing module is used to compare the target detection voltage with a preset reference voltage; The short-circuit processing module is further used to determine that the OLED device is in a short-circuit state when the target detection voltage is greater than the preset reference voltage; The short-circuit processing module is further used to disconnect the circuit where the OLED device is located in the OLED driving module when the OLED device is in the short-circuit state.

2. The short circuit protection circuit according to claim 1, It is characterized in that The short circuit detection module includes: a current detection unit and a voltage amplification unit; The current detection unit is connected to the voltage amplification unit and the OLED device in the OLED driving module respectively, and the voltage amplification unit is connected to the short-circuit processing module; The current detection unit is used to detect the current loop current on the OLED device, and convert the current loop current into an initial loop voltage and then output it to the voltage amplification unit; The voltage amplification unit is used to amplify the initial loop voltage to obtain the target loop voltage; The voltage amplifying unit is further used to perform analog-to-digital conversion on the target loop voltage to obtain the target detection voltage in the form of a digital signal, and output the target detection voltage to the short-circuit processing module.

3. The short circuit protection circuit as claimed in claim 2, It is characterized in that The current detection unit includes: a first MOS tube and a current detection resistor; The drain of the first MOS tube is connected to the anode of the OLED device, the source of the first MOS tube is respectively connected to the first end of the current detection resistor and the voltage amplification unit, and the second end of the current detection resistor is grounded.

4. The short circuit protection circuit as claimed in claim 3, It is characterized in that The voltage amplification module includes: a first operational amplifier, a first resistor, a second resistor, a third resistor and an analog-to-digital converter; The inverting input terminal of the first operational amplifier is respectively connected to the first end of the first resistor and the first end of the second resistor, the second end of the first resistor is grounded, the second end of the second resistor is respectively connected to the output terminal of the first operational amplifier and the input terminal of the analog-to-digital converter, and the output terminal of the analog-to-digital converter is connected to the short-circuit processing module; The non-inverting input terminal of the first operational amplifier is connected to the first terminal of the third resistor, and the second terminal of the third resistor is respectively connected to the source of the first MOS tube and the first terminal of the current detection resistor.

5. The short circuit protection circuit according to claim 1, It is characterized in that The short-circuit processing module includes: a voltage comparator and a short-circuit processing driving tube; The non-inverting input terminal of the voltage comparator is connected to the comparator reference source, the inverting input terminal of the voltage comparator is connected to the voltage amplification module, the output terminal of the voltage comparator is connected to the gate of the short-circuit processing driving tube, the drain of the short-circuit processing driving tube is connected to the power supply terminal in the OLED driving module, and the source of the short-circuit processing driving tube is connected to the anode of the OLED device; The voltage comparator is used to compare the target detection voltage with the preset reference voltage input by the comparator reference source; The voltage comparator is also used to control the on-off state of the short-circuit processing driving tube according to the voltage comparison result.

6. The short circuit protection circuit as claimed in claim 5, It is characterized in that The voltage comparator is further used to output a low-level driving signal to the short-circuit processing driving tube when the target detection voltage is greater than the preset reference voltage, so as to put the short-circuit processing driving tube in a disconnected state; The short-circuit processing driving tube is used to disconnect the circuit between the OLED device and the power supply end when in the disconnected state.

7. The short circuit protection circuit as claimed in claim 5, It is characterized in that The voltage comparison unit is further used to output a high-level driving signal to the short-circuit processing driving tube when the target detection voltage is less than the preset reference voltage, so that the short-circuit processing driving tube is in a closed state; The short-circuit processing driving tube is used to connect the circuit between the OLED device and the power supply end when in the closed state.

8. An array substrate, It is characterized in that The array substrate comprises: an OLED driving module and the short-circuit protection circuit according to any one of claims 1 to 6; The OLED driving module includes: an OLED device, a scanning signal driving tube, an OLED device driving tube and a first capacitor; The drain of the scanning signal driving tube is connected to the signal line, the source of the scanning signal driving tube is respectively connected to the gate of the OLED device driving tube and the first end of the first capacitor, and the second end of the first capacitor is respectively connected to the power supply end and the drain of the short-circuit processing driving tube in the short-circuit protection circuit; The drain electrode of the OLED device driving tube is connected to the source electrode of the short-circuit processing driving tube, the source electrode of the OLED device driving tube is connected to the anode electrode of the OLED device, and the cathode electrode of the OLED device is grounded.

9. A display device, It is characterized in that The display device comprises the array substrate according to claim 8.

10. A short circuit protection method, It is characterized in that The method is applied to the short-circuit protection circuit according to any one of claims 1 to 8, and the method comprises: Convert the current loop current on the OLED device into a target detection voltage; comparing the target detection voltage with a preset reference voltage; When the target detection voltage is greater than the preset reference voltage, determining that the OLED device is in a short-circuit state; When the OLED device is in the short-circuit state, the circuit in which the OLED device is located in the OLED driving module is disconnected.

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