Touch electrode short circuit detection method, system and display device

Abstract

The application relates to a touch electrode short circuit detection method and system and a display device. When a to-be-tested touch electrode is connected to a negative voltage power supply, a first output end of a current transmitter is subjected to voltage collection to obtain a first voltage sampling value. When the to-be-tested touch electrode is disconnected from the negative voltage power supply, the first output end of the current transmitter is subjected to voltage collection to obtain a second voltage sampling value. Then, in combination with the first voltage sampling value, the second voltage sampling value and a preset equivalent resistance calculation model, an equivalent resistance value of the to-be-tested touch electrode is obtained, and finally, in combination with a preset resistance threshold value, short circuit verification of the to-be-tested touch electrode is completed. Through the scheme, when a short circuit fault occurs in the touch electrode, the short circuit fault can be timely investigated and eliminated, so that relevant fault repair processing can be performed. The display device is prevented from being subjected to touch display in a touch electrode short circuit state, and the problem of low touch accuracy of the display device caused by the touch electrode short circuit is effectively alleviated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of touch display, in particular to a touch electrode short circuit detection method, system and display device. BACKGROUND

[0002] Touch and display driver integration (TDDI) can integrate touch chip and display chip into a single chip, so that human-computer interaction is more simple and convenient. Therefore, TDDI is widely applied to display devices of various electronic products.

[0003] The display device using TDDI integrates a large number of touch electrodes and complex wiring, which increases the risk of touch electrode short circuit during operation. The touch electrode short circuit will reduce the touch accuracy of the display device. Therefore, it is necessary to seek a method to detect the short circuit state of the touch electrode, so as to troubleshoot the short circuit fault of the touch electrode in time. SUMMARY

[0004] Therefore, it is necessary to provide a touch electrode short circuit detection method, system and display device to alleviate the problem of low touch accuracy of the display device caused by touch electrode short circuit.

[0005] A touch electrode short circuit detection method comprises: obtaining a first voltage sampling value of a first output end of a current transmitter when a to-be-tested touch electrode is connected to a negative voltage power supply; the first output end of the current transmitter is connected to ground through a first resistor, and the second output end of the current transmitter is connected to a multiplexer through a second resistor; each touch electrode is connected to the multiplexer, and each touch electrode is connected to the negative voltage power supply through a switch device; the to-be-tested touch electrode is connected to the second output end of the current transmitter through the second resistor after being selected by the multiplexer; obtaining a second voltage sampling value of the first output end of the current transmitter when the to-be-tested touch electrode is not connected to the negative voltage power supply; obtaining an equivalent resistance value of the to-be-tested touch electrode according to the first voltage sampling value, the second voltage sampling value and a preset equivalent resistance calculation model; and verifying the short circuit of the to-be-tested touch electrode according to the equivalent resistance value and a preset resistance threshold.

[0006] The short circuit detection method of the touch electrode, each touch electrode is connected to a negative voltage power supply through a switching device, and each touch electrode is also connected to a multiplexer. When the short circuit detection of the touch electrode is performed, the multiplexer is used to select the to-be-tested touch electrode which needs to be verified for short circuit, so that the to-be-tested touch electrode is connected to the second output end of the current transmitter through the multiplexer and the second resistor. First, when the to-be-tested touch electrode is connected to the negative voltage power supply by turning on the switching device corresponding to the to-be-tested touch electrode, the first output end of the current transmitter is collected for a voltage to obtain a first voltage sampling value. Then, when the to-be-tested touch electrode is disconnected from the negative voltage power supply by turning off the switching device corresponding to the to-be-tested touch electrode, the first output end of the current transmitter is collected for a voltage to obtain a second voltage sampling value. Then, the equivalent resistance value of the to-be-tested touch electrode can be obtained by combining the first voltage sampling value and the second voltage sampling value. Finally, the short circuit verification of the to-be-tested touch electrode is completed by comparing the equivalent resistance value with a preset resistance threshold. The short circuit detection of the touch electrode can be realized by using a simple circuit structure. When the touch electrode is short-circuited, the short circuit can be detected in time, so that the related fault repair processing can be performed. The display device can be prevented from being displayed by touch in the short circuit state of the touch electrode, and the problem of low touch accuracy of the display device caused by the short circuit of the touch electrode can be effectively alleviated.

[0007] In one embodiment, the output current of the first output end of the current transmitter is a preset multiple of the output current of the second output end of the current transmitter. Before the equivalent resistance value of the to-be-tested touch electrode is obtained according to the first voltage sampling value, the second voltage sampling value and a preset equivalent resistance calculation model, the preset equivalent resistance calculation model is obtained according to the preset multiple, the resistance value of the first resistor, the voltage of the input power supply, the voltage of the negative voltage power supply, and the output voltage parameter of the first output end of the current transmitter when the to-be-tested touch electrode is connected to and disconnected from the negative voltage power supply.

[0008] In one embodiment, the preset equivalent resistance calculation model is obtained according to the preset multiple, the resistance value of the first resistor, the voltage of the input power supply, the voltage of the negative voltage power supply, and the output voltage parameter of the first output end of the current transmitter when the touch electrode under test is connected to the negative voltage power supply, including: obtaining a first resistance model according to the preset multiple, the resistance value of the first resistor, the voltage of the input power supply, the voltage of the negative voltage power supply, and the output voltage parameter of the first output end of the current transmitter when the touch electrode under test is connected to the negative voltage power supply; obtaining a second resistance model according to the preset multiple, the resistance value of the first resistor, the voltage of the input power supply, the voltage of the negative voltage power supply, and the output voltage parameter of the first output end of the current transmitter when the touch electrode under test is not connected to the negative voltage power supply; and obtaining the preset equivalent resistance calculation model according to the first resistance model and the second resistance model.

[0009] In one embodiment, the short circuit verification of the touch electrode under test is performed according to the equivalent resistance value and a preset resistance threshold, including: when the equivalent resistance value is less than or equal to the preset resistance threshold, obtaining a verification result that the touch electrode under test is short-circuited; and when the equivalent resistance value is greater than the preset resistance threshold, obtaining a verification result that the touch electrode under test is not short-circuited.

[0010] In one embodiment, after the short circuit verification of the touch electrode under test is performed according to the equivalent resistance value and a preset resistance threshold, the method further includes: determining whether all the touch electrodes have completed the short circuit verification; if there is a touch electrode that has not completed the short circuit verification, controlling the multiplexer to select a next touch electrode that has not completed the short circuit verification as the touch electrode under test, and returning to the step of obtaining the first voltage sampling value of the first output end of the current transmitter when the touch electrode under test is connected to the negative voltage power supply, until all the touch electrodes have completed the short circuit verification.

[0011] In one embodiment, the determination of whether all the touch electrodes have completed the short circuit verification includes: accumulating the number of verifications to obtain the number of touch electrodes that have completed the short circuit verification; and if the number is less than a preset number threshold, it is considered that there is a touch electrode that has not completed the short circuit verification.

[0012] A touch electrode short circuit detection system, comprising: a current transmitter, a first resistor, a second resistor, a multiplexer, a switch device and a control device, an input end of the current transmitter is connected to an input power supply, a first end of the first resistor is connected to a first output end of the current transmitter, a second end of the first resistor is grounded, the multiplexer is connected to a second output end of the current transmitter through the second resistor, each touch electrode is connected to the multiplexer, and each touch electrode is connected to a negative voltage power supply through the switch device; the control device is connected to the first end of the first resistor, the multiplexer and each switch device are connected to the control device, and the control device is used for short circuit verification of each touch electrode according to the touch electrode short circuit detection method.

[0013] In one embodiment, the current transmitter comprises an amplification circuit, a current mirror circuit, a first switch tube, a third resistor, a first current source and a second current source, the current value of the second current source is a preset multiple of the current value of the first current source; the amplification circuit is connected to an input power supply, the amplification circuit is connected to the current mirror circuit and a power supply, the current mirror circuit is connected to a second end of the first switch tube, the amplification circuit is connected to a control end of the first switch tube, a first end of the first switch tube is connected to the first current source, a first end of the third resistor and the amplification circuit, a second end of the third resistor is grounded, the first end of the first switch tube is connected to the multiplexer through the second resistor, the current mirror circuit is connected to the first end of the first resistor and the second current source, and the amplification circuit, the first current source and the second current source are all grounded.

[0014] In one embodiment, the amplification circuit comprises a second switch tube, a third switch tube, a fourth switch tube, a fifth switch tube and a third current source; a control end of the second switch tube is connected to an input power supply, a first end of the second switch tube is connected to a first end of the third switch tube, and a common end is connected to the third current source, the third current source is grounded, a control end of the third switch tube is connected to a first end of the first switch tube, a second end of the third switch tube is connected to a first end of the fifth switch tube and a control end of the first switch tube, a second end of the fifth switch tube is connected to the current mirror circuit and a power supply, a second end of the second switch tube is connected to a first end of the fourth switch tube, a second end of the fourth switch tube is connected to a second end of the fifth switch tube, and a control end of the fourth switch tube is connected to a control end of the fifth switch tube and the first end of the fourth switch tube.

[0015] In one embodiment, the current mirror circuit comprises a sixth switch tube and a seventh switch tube, a first end of the sixth switch tube is connected to a second end of the first switch tube, a control end of the sixth switch tube is connected to the first end of the sixth switch tube and a control end of the seventh switch tube, a second end of the sixth switch tube is connected to the amplification circuit and a power supply, a second end of the seventh switch tube is connected to the second end of the sixth switch tube, and a first end of the seventh switch tube is connected to the second current source and a first end of the first resistor.

[0016] A display device comprises the touch electrode short circuit detection system. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0018] Figure 1 The flowchart of the touch electrode short circuit detection method in an embodiment of the present application is shown.

[0019] Figure 2 The structural schematic diagram of the touch electrode short circuit detection system in an embodiment of the present application is shown.

[0020] Figure 3 The flowchart of the touch electrode short circuit detection method in another embodiment of the present application is shown.

[0021] Figure 4 The analysis flowchart of the preset equivalent resistance calculation model in an embodiment of the present application is shown.

[0022] Figure 5 The flowchart of the touch electrode short circuit detection method in still another embodiment of the present application is shown.

[0023] Figure 6 The flowchart of the touch electrode short circuit detection method in still another embodiment of the present application is shown.

[0024] Figure 7 The flowchart of the touch electrode short circuit detection method in an embodiment of the present application is shown.

[0025] Figure 8 The structural schematic diagram of the current transmitter in an embodiment of the present application is shown.

[0026] Figure 9 The structural schematic diagram of the current transmitter in another embodiment of the present application is shown. DETAILED DESCRIPTION

[0027] For the purpose of promoting the understanding of the present application, the present application will be more fully described by referring to the attached drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the present application to those skilled in the art.

[0028] Referring to Figure 1 A touch electrode short circuit detection method, comprising steps 102, 104, 106 and 108.

[0029] Step 102, when the to-be-tested touch electrode is connected to a negative voltage power supply, a first voltage sampling value of a first output end of a current conveyor is obtained.

[0030] Specifically, referring to Figure 2 The first output end (i.e. Td) of the current conveyor 10 is connected to ground through the first resistor T1, the second output end (i.e. Ts) of the current conveyor 10 is connected to the multiplexer 20 through the second resistor T2, each touch electrode TE is connected to the multiplexer 20, and each touch electrode TE is connected to the negative voltage power supply (i.e. VCOM) through a switch device 30. After the to-be-tested touch electrode is selected by the multiplexer 20, the touch electrode connected to the second output end of the current conveyor 10 through the second resistor T2.

[0031] The current conveyor is a current-mode circuit, which can be used to conveniently realize a voltage-mode signal processing circuit and a current-mode signal processing circuit, and realize various analog signal processing functions. The multiplexer is a data selector, which can select any one of multiple data transmission paths according to needs. In the technical solution of the present application, the multiplexer can be used to select different touch electrodes to be connected to the second output end of the current conveyor during the touch electrode short circuit detection process, so as to realize short circuit verification operations of different touch electrodes. Correspondingly, the to-be-tested touch electrode is the touch electrode connected to the second output end of the current conveyor through the second resistor after being selected by the multiplexer.

[0032] The output current value of the first output end of the current conveyor is converted into a voltage value by the first resistor at the position, and the voltage value is transmitted to the control device connected to the first end of the current conveyor. Similarly, each switch device and the multiplexer are connected to the control device, and the entire touch electrode short circuit detection method is executed by the control device.

[0033] When the short circuit detection is performed, the control device first controls the multiplexer to act, and the touch electrode to be tested (i.e., the touch electrode to be tested) is connected through the multiplexer. Then the control device controls the switch device corresponding to the touch electrode to be tested to be turned on, so that the touch electrode to be tested is connected with the negative voltage power supply. At this time, the voltage sampling is performed at the first output end of the current transmitter, and the first voltage sampling value is obtained.

[0034] It should be pointed out that the specific type of the multiplexer is not unique. In actual detection scenarios, the number of touch electrodes in the display device is different, and the type of the multiplexer will also be different. For example, it can be a four-to-one multiplexer, an eight-to-one multiplexer, or a sixteen-to-one multiplexer, etc.

[0035] It can be understood that in other embodiments, when the number of touch electrodes of the display device is large, and it is not enough to connect all the touch electrodes to the touch electrode short circuit detection system through one multiplexer, a plurality of multiplexers can also be provided, and each multiplexer is responsible for connecting a part of the touch electrodes. This ensures that all touch electrodes can be connected to the second end of the current transmitter through the multiplexer and the second resistor. When the touch electrode short circuit detection system includes a plurality of multiplexers, each multiplexer is connected to the second end of the second resistor. During actual testing, only the channel corresponding to the touch electrode to be tested in the multiplexer corresponding to the touch electrode to be tested needs to be turned on.

[0036] In step 104, when the touch electrode to be tested is not connected to the negative voltage power supply, the second voltage sampling value of the first output end of the current transmitter is obtained.

[0037] Specifically, after the control device controls the multiplexer to select the touch electrode to be tested to be connected to the second output end of the current transmitter, and the switch device corresponding to the touch electrode to be tested is turned on, the control device controls the switch device corresponding to the touch electrode to be tested to switch from the on state to the off state, so that the connection between the touch electrode to be tested and the negative voltage power supply is disconnected. In this state, the voltage sampling is performed at the first output end of the current transmitter, and the second voltage sampling value is obtained.

[0038] It should be pointed out that in one embodiment, when the short circuit verification of one touch electrode to be tested is performed, the connections between the remaining touch electrodes and the negative voltage power supply are maintained. In this way, in addition to avoiding low test efficiency caused by frequent switching, the remaining touch electrodes can also be prevented from interfering with the test during the detection of the touch electrode to be tested, thereby effectively improving the test accuracy.

[0039] It can be understood that the specific structure of the control device is not unique. In a more detailed embodiment, the control device comprises an analog to digital converter (ADC) and a processor, wherein the analog to digital converter is connected to the processor, the analog to digital converter is connected to the first output end of the current transmitter, each switching device and the multiplexer are respectively connected to the processor, the output voltage of the first output end of the current transmitter is sampled by the analog to digital converter, the first voltage sampling value and the second voltage sampling value are respectively obtained in different states, and are sent to the processor, and the processor executes a related short circuit detection process.

[0040] In step 106, the equivalent resistance value of the to-be-tested touch electrode is obtained according to the first voltage sampling value, the second voltage sampling value and a preset equivalent resistance calculation model.

[0041] Specifically, the preset equivalent resistance calculation model represents the corresponding relationship between the first voltage sampling value, the second voltage sampling value and the equivalent resistance value of the to-be-tested touch electrode, that is, only the first voltage sampling value and the second voltage sampling value are brought into the preset equivalent resistance calculation model, and the equivalent resistance value can be obtained. The specific mode of the control device in short circuit verification according to the first voltage sampling value and the second voltage sampling value is not unique. Since there is a significant difference in the equivalent resistance value of the touch electrode in the short circuit state and the normal operating state, if the connection between the touch electrode and the circuit is disconnected, the equivalent resistance value of the touch electrode will be infinite when the touch electrode is in normal operation and the connection between the touch electrode and the circuit is disconnected. However, if the connection between the touch electrode and the circuit is disconnected, but the touch electrode is in a short circuit state, the equivalent resistance value of the touch electrode will be in a relatively normal range.

[0042] Based on the above principle, after obtaining the first voltage sampling value and the second voltage sampling value, the preset equivalent resistance calculation model is combined for analysis to obtain the equivalent resistance value of the to-be-tested touch electrode.

[0043] In step 108, the to-be-tested touch electrode is subjected to short circuit verification according to the equivalent resistance value and a preset resistance threshold.

[0044] Specifically, a preset resistance threshold is pre-stored in the control device. After the control device obtains the equivalent resistance value of the to-be-tested touch electrode, the equivalent resistance value is compared and analyzed with the preset resistance threshold, and according to the comparison result, the verification result of whether the to-be-tested touch electrode is short-circuited is obtained.

[0045] It can be understood that in an embodiment, after the to-be-tested touch electrode is subjected to short circuit verification, the control device will also output the verification result in the form of text display, light display and the like, so that the user can know the detection result in time.

[0046] The above short circuit detection method of the touch electrode, each touch electrode is connected to the negative voltage power supply through the switching device, and each touch electrode is also connected to the multiplexer. When the short circuit detection of the touch electrode is performed, the multiplexer is used to select the to-be-tested touch electrode which needs to be verified for short circuit, so that the to-be-tested touch electrode is connected to the second output end of the current transmitter through the multiplexer and the second resistor. First, when the to-be-tested touch electrode is connected to the negative voltage power supply by turning on the switching device corresponding to the to-be-tested touch electrode, the first output end of the current transmitter is collected for voltage to obtain a first voltage sampling value. Then, when the to-be-tested touch electrode is disconnected from the negative voltage power supply by turning off the switching device corresponding to the to-be-tested touch electrode, the first output end of the current transmitter is collected for voltage to obtain a second voltage sampling value. Then, the equivalent resistance value of the to-be-tested touch electrode can be obtained by combining the first voltage sampling value and the second voltage sampling value. Finally, the short circuit verification of the to-be-tested touch electrode is completed by comparing the equivalent resistance value with a preset resistance threshold. The above scheme can realize the short circuit detection of the touch electrode by using a simple circuit structure. When the touch electrode has a short circuit fault, the fault can be found out in time, so that relevant fault repair processing can be performed. The display device can be prevented from being controlled and displayed in the short circuit state of the touch electrode, and the problem of low touch accuracy of the display device caused by the short circuit of the touch electrode can be effectively alleviated.

[0047] Please refer to Figure 3 In one embodiment, the output current of the first output end of the current transmitter is a preset multiple of the output current of the second output end of the current transmitter. Before step 106, the method further includes step 101.

[0048] In step 101, a preset equivalent resistance calculation model is obtained according to the preset multiple, the resistance value of the first resistor, the voltage of the input power supply and the voltage of the negative voltage power supply, and the output voltage parameters of the first output end of the current transmitter when the to-be-tested touch electrode is connected to and disconnected from the negative voltage power supply.

[0049] Specifically, step 101 can be performed at any position before step 106, that is, before step 102 or at any position between step 102 and step 106. As long as the preset equivalent resistance calculation model is obtained and pre-stored in the control device before the analysis is performed in combination with the preset equivalent resistance calculation model, the operation can be performed. Moreover, step 101 is not necessarily performed. For the same display device, the preset equivalent resistance calculation model can be obtained by performing the operation for the first time and stored in the control device. When the short circuit detection of the touch electrode is performed subsequently, the first voltage sampling value and the second voltage sampling value are directly obtained, and the preset equivalent resistance calculation model is called for calculation.

[0050] The output current value of the first output end of the current transmitter is a preset multiple of the output current value of the second output end, and the output current value of the second output end of the current transmitter can be obtained according to the accessed voltage value and the equivalent resistance value between the second output end of the current transmitter and the negative voltage power supply. When the to-be-tested touch electrode is accessed and not accessed to the negative voltage power supply, the equivalent resistance value between the second output end of the current transmitter and the negative voltage power supply will change to a certain extent. Through the relationship between the output current of the first output end of the current transmitter and the output current of the second output end, the change of the output voltage parameter of the first output end of the current transmitter when the to-be-tested touch electrode is accessed and not accessed to the negative voltage power supply can be converted into the change of the equivalent resistance value between the second output end of the current transmitter and the negative voltage power supply, and finally the preset equivalent resistance calculation model can be constructed.

[0051] Further, please refer to Figure 4 In one embodiment, step 101 comprises step 402, step 404 and step 406.

[0052] Step 402, according to the preset multiple, the resistance value of the first resistor, the voltage of the input power supply and the voltage of the negative voltage power supply, and the output voltage parameter of the first output end of the current transmitter when the to-be-tested touch electrode is accessed to the negative voltage power supply, a first resistor model is obtained.

[0053] Step 404, according to the preset multiple, the resistance value of the first resistor, the voltage of the input power supply and the voltage of the negative voltage power supply, and the output voltage parameter of the first output end of the current transmitter when the to-be-tested touch electrode is not accessed to the negative voltage power supply, a second resistor model is obtained.

[0054] Step 406, according to the first resistor model and the second resistor model, a preset equivalent resistance calculation model is obtained.

[0055] Specifically, when the to-be-tested touch electrode is accessed to the negative voltage power supply, there is:

[0056]

[0057] Wherein, Is1 is the output current value of the second end of the current transmitter when the to-be-tested touch electrode is accessed to the negative voltage power supply, Vref is the input voltage of the input end of the current transmitter (i.e. the voltage of the input power supply), VCOM is the voltage of the negative voltage power supply, R2 is the resistance value of the second resistor, and Rp is the equivalent parasitic resistance from the to-be-tested touch electrode to the second output end of the current transmitter.

[0058] Suppose the preset multiple is N, then Id1=N*Is1, and there is:

[0059] Vd1=R1*Id1=N*Is1*R1

[0060] wherein Vd1 is the output voltage parameter of the first output end of the current transfer device when the touch electrode under test is connected to the negative voltage source, R1 is the resistance value of the first resistor, Id1 is the output current value of the first output end of the first current transfer device, and finally the following is obtained:

[0061]

[0062] That is, at this time, the first resistor calculation model is obtained according to the output voltage parameter of the first output end of the current transfer device, the preset multiple, the resistance value of the first resistor, the voltage of the input power source and the voltage of the negative voltage source.

[0063]

[0064] When the touch electrode under test is not connected to the negative voltage source, the following is obtained: wherein Is2 is the output current value of the second end of the current transfer device when the touch electrode under test is not connected to the negative voltage source, Vref is the input voltage of the input end of the current transfer device, VCOM is the voltage of the negative voltage source, R2 is the resistance value of the second resistor, Rp is the equivalent parasitic resistance from the touch electrode under test to the second output end of the current transfer device, and Rshort is the equivalent resistance of the touch electrode under test. Based on the same principle, the following is obtained:

[0065]

[0066] That is, at this time, the second resistor calculation model is obtained according to the output voltage parameter of the first output end of the current transfer device, the preset multiple, the resistance value of the first resistor, the voltage of the input power source and the voltage of the negative voltage source.

[0067]

[0068] After obtaining the first resistor calculation model and the second resistor calculation model, since the resistance value of the first resistor and the equivalent parasitic resistance in the first resistor calculation model are fixed, the preset equivalent resistance calculation model is obtained by subtracting the two equations:

[0069]

[0070] In the formula, the input voltage value Vref, the voltage value VCOM of the negative voltage power supply, the preset multiple N, and the resistance value R1 of the first resistor are determined when the test system is built, and these parameters can be pre-stored in the processor of the control device. When the equivalent resistance value needs to be calculated, the first voltage sampling value (i.e., the output voltage parameter Vd1 of the first output end of the first current transmitter when the touch electrode under test is connected to the negative voltage power supply), the second voltage sampling value (i.e., the output voltage parameter Vd2 of the second output end of the first current transmitter when the touch electrode under test is not connected to the negative voltage power supply), and the pre-stored parameters are directly brought in to calculate the equivalent resistance value Rshort according to the above model.

[0071] It can be understood that in another embodiment, the first resistor calculation model and the second resistor calculation model can also be pre-stored in the control device. When the equivalent resistance is calculated, the sum of the equivalent resistances between the second end of the current transmitter and the negative voltage power supply, i.e., the sum of the resistance value of the first resistor and the equivalent parasitic resistance, is first calculated according to the first voltage sampling value and the first resistor calculation model. Then, the sum of the equivalent resistances between the second end of the current transmitter and the negative voltage power supply, i.e., the sum of the resistance value of the first resistor, the equivalent parasitic resistance, and the equivalent resistance value, is calculated according to the second voltage sampling value and the second resistor calculation model. Finally, the two calculated sums are subtracted to obtain the equivalent resistance value of the touch electrode under test.

[0072] The above scheme brings the first voltage sampling value and the second voltage sampling value obtained by collection into the preset equivalent resistance calculation model to calculate the corresponding equivalent resistance value, which has the advantages of simple calculation method and fast calculation speed, thereby improving the detection efficiency of the touch electrode short circuit detection method.

[0073] Please refer to Figure 5 In one embodiment, step 108 includes step 504 and step 506.

[0074] Step 504: when the equivalent resistance value is less than or equal to the preset resistance threshold, a verification result that the touch electrode under test is short-circuited is obtained; and step 506: when the equivalent resistance value is greater than the preset resistance threshold, a verification result that the touch electrode under test is not short-circuited is obtained.

[0075] Specifically, the preset resistance threshold is not unique in setting method, and can be the maximum resistance value obtained by measuring the equivalent resistance values of the touch electrodes in the short-circuit state. The preset resistance threshold can also be set to be greater than the maximum resistance value that can be reached by the touch electrodes in the short-circuit state, and different choices can be made according to the specific needs.

[0076] In this embodiment, the preset resistance threshold is set as the maximum value of the equivalent resistance of each touch electrode in the short circuit state. If the equivalent resistance obtained in the detection process is less than or equal to the preset resistance threshold, it is considered that the touch electrode under test is in the short circuit state, otherwise, it is considered that the touch electrode under test is not short-circuited.

[0077] It should be noted that the size of the preset resistance threshold can also be set to be different in different types of display devices, and can be flexibly selected in combination with actual scenes.

[0078] It can be understood that the size of the preset resistance threshold is not unique, and in an embodiment, the preset resistance threshold can be set to 10 kilo-ohms. This scheme directly compares and analyzes the equivalent resistance with the preset resistance threshold, and the short circuit verification result of the touch electrode under test can be obtained, which has the advantages of simple verification mode and high verification efficiency.

[0079] Please refer to Figure 6 In an embodiment, after step 108, the method further includes steps 602 and 604.

[0080] Step 602: determining whether all touch electrodes have completed short circuit verification;

[0081] If there is a touch electrode that has not completed short circuit verification, step 604 is performed: controlling the multiplexer to select the next touch electrode that has not completed short circuit verification as the touch electrode under test. And return to the step of obtaining the first voltage sampling value of the first output end of the current transmitter when the touch electrode under test is connected to the negative voltage power supply, until all touch electrodes have completed short circuit verification.

[0082] Specifically, when the short circuit verification of the touch electrode under test is performed by using the above detection method, since the number of touch electrodes in the display device is often large, and the number of touch electrodes of different display devices is also not completely the same. Therefore, during the short circuit detection process, each time the short circuit verification of the touch electrode under test is completed, it is necessary to analyze whether all touch electrodes have completed short circuit verification. When there is a touch electrode under test that has not completed short circuit verification, the short circuit verification of the next touch electrode under test will be started, and the specific verification method is similar to the above, which will not be described here again, until all touch electrodes have completed short circuit verification, and the touch electrode short circuit detection process is ended. Through the above scheme, it can be ensured that each touch electrode can realize short circuit verification, and the situation of missing detection is avoided, and the detection reliability of the touch electrode short circuit detection method is improved.

[0083] Further, in an embodiment, step 602 includes: accumulating the verification times to obtain the number of touch electrodes that have completed short circuit verification.

[0084] Specifically, if the number is less than the preset number threshold, it is considered that there is a touch electrode that has not completed short circuit verification. The number of touch electrodes possessed by the TDDI corresponding to the touch display panel after the design is completed is determined, and the number of touch electrodes possessed by the TDDI can be pre-stored in the control device to obtain the preset number threshold. In order to ensure that each touch electrode can achieve short circuit verification during short circuit detection, the scheme accumulates the verification number each time the short circuit verification is completed, compares and analyzes the accumulated number with the preset number threshold, and if the accumulated number does not reach the preset number threshold, it means that the short circuit verification of all touch electrodes has not been completed. The control device will control the multiplexer to select the next touch electrode to be tested, and the above scheme is used to perform short circuit verification on the next touch electrode to be tested.

[0085] It should be pointed out that the size of the preset number threshold is not unique, and the preset number threshold will also be different in different types of display devices, as long as the preset number threshold is set to be consistent with the number of touch electrodes of the touch device.

[0086] The above scheme detects whether all touch electrodes have completed short circuit verification by means of counting accumulation, which has the advantages of simple judgment method and high judgment precision.

[0087] In order to facilitate understanding of the technical scheme of the present application, the present application will be explained and described below in combination with detailed embodiments. It can be combined with reference to Figure 7 The control device includes a processor and an ADC, and when performing short circuit detection of the touch electrode, the processor controls all the switching devices to enter the conduction state, so that all the touch electrodes are connected to the negative voltage power supply. The processor first controls the multiplexer to select one of the touch electrodes as the touch electrode to be tested and connects it to the second output end of the current transmitter. In this state, the ADC collects the voltage at the first output end of the current transmitter in combination with the first resistor, obtains the first voltage sampling value and transmits it to the processor. Then the processor controls the switching device corresponding to the touch electrode to be tested to be disconnected, so that it is disconnected from the negative voltage power supply. The ADC collects the voltage in the same way to obtain the second voltage sampling value and transmits it to the processor.

[0088] The processor calculates the equivalent resistance value of the touch electrode to be tested in combination with the first voltage sampling value, the second voltage sampling value and the preset equivalent resistance calculation model (specifically ), and compares and analyzes the equivalent resistance value with the preset resistance threshold. If it is less than or equal to the preset resistance threshold, the verification result of the short circuit of the touch electrode to be tested is obtained; if it is greater than the preset resistance threshold, it is considered that no short circuit has occurred.

[0089] When the short circuit verification of a to-be-tested touch electrode is completed, the processor controls the switch device corresponding to the to-be-tested touch electrode to be closed, and accumulates the verification times by one, to obtain the number of touch electrodes that have completed the short circuit verification. If the number is equal to the preset number threshold, the short circuit detection is ended. If the number is less than the preset number threshold, the processor selects the next touch electrode that has not completed the short circuit verification as a to-be-tested electrode, and performs the same operation as the short circuit verification described above, until all the touch electrodes complete the short circuit verification.

[0090] Please refer to Figure 2 A touch electrode short circuit detection system, comprising: a current transmitter 10, a first resistor T1, a second resistor T2, a multiplexer 20, a switch device 30 and a control device 40, the input end of the current transmitter 10 is connected to an input power supply, the first end of the first resistor T1 is connected to the first output end of the current transmitter 10, the second end of the first resistor T1 is grounded, the second output end of the current transmitter 10 is connected to the multiplexer 20 through the second resistor T2, each touch electrode is connected to the multiplexer 20, and each touch electrode is connected to a negative voltage power supply through a switch device 30; the control device 40 is connected to the first end of the first resistor T1, and the multiplexer 20 and each switch device 30 are connected to the control device 40, and the control device 40 is used for performing short circuit verification on each touch electrode according to the touch electrode short circuit detection method.

[0091] Specifically, by the multiplexer 20, different touch electrodes can be selected to access the detection system during the touch electrode short circuit detection process, so as to realize the short circuit detection operation of different touch electrodes. Correspondingly, the to-be-tested touch electrode is the touch electrode that is selected by the multiplexer 20 and then accesses the second output end of the current transmitter 10 through the second resistor T2.

[0092] The first output end of the current transmitter 10 outputs a first current value, which is converted into a corresponding voltage value by the first resistor T1 arranged at the position, and is transmitted to the control device 40 connected to the first end of the current transmitter 10. Similarly, each switch device 30 and the multiplexer 20 are connected to the control device 40, and the entire touch electrode short circuit detection method is executed by the control device 40.

[0093] During the short circuit detection, the control device 40 first controls the multiplexer 20 to act, so that the touch electrode to be tested (i.e. the to-be-tested touch electrode) accesses through the multiplexer 20. Then the control device 40 controls the switch device 30 corresponding to the to-be-tested touch electrode to be turned on, so that the to-be-tested touch electrode is connected to the negative voltage power supply. At this time, voltage sampling is performed at the first output end of the current transmitter 10, to obtain a first voltage sampling value.

[0094] Then the control device 40 controls the switch device 30 corresponding to the touch electrode to be tested to switch from the on state to the off state, so that the connection between the touch electrode to be tested and the negative voltage source is disconnected. In this state, the first output end of the current transmitter 10 is sampled to obtain a second voltage sampling value.

[0095] It should be noted that in one embodiment, when the short circuit detection of a touch electrode is performed, the connection between the remaining touch electrodes and the negative voltage source is maintained, except that the connection between the touch electrode to be tested and the negative voltage source needs to be switched. In this way, in addition to avoiding low test efficiency caused by frequent switching, the remaining touch electrodes can also be prevented from interfering with the test during the detection of the touch electrode to be tested, thereby effectively improving the test accuracy.

[0096] After obtaining the first voltage sampling value and the second voltage sampling value, the control device 40 analyzes the preset equivalent resistance calculation model to obtain the equivalent resistance value of the touch electrode to be tested. The control device 40 pre-stores a preset resistance threshold value. After obtaining the equivalent resistance value of the touch electrode to be tested, the control device 40 compares and analyzes the equivalent resistance value with the preset resistance threshold value, and obtains the verification result of whether the touch electrode to be tested is short-circuited according to the comparison result.

[0097] Please refer to Figure 8 In one embodiment, the current transmitter 10 includes an amplification circuit 11, a current mirror circuit 12, a first switch tube M1, a third resistor T3, a first current source S1, and a second current source S2, the current value of the second current source S2 is a preset multiple of the current value of the first current source S1; the amplification circuit 11 is connected to an input power source (i.e., Vref), the amplification circuit 11 is connected to the current mirror circuit 12 and a power source, the current mirror circuit 12 is connected to the second end of the first switch tube M1, the amplification circuit 11 is connected to the control end of the first switch tube M1, the first end of the first switch tube M1 is connected to the first end of the third resistor T3, the first end of the amplification circuit 11, and the first end of the first current source S1, the second end of the third resistor T3 is grounded, the first end of the first switch tube M1 is connected to the multi-channel selector 20 (not shown in the figure) through the second resistor T2, the current mirror circuit 12 is connected to the first end of the first resistor T1 (not shown in the figure) and the second current source S2, and the amplification circuit 11, the first current source S1, and the second current source S2 are all grounded.

[0098] Specifically, in the scheme, the positive input end of the amplification circuit 11 is connected to the input power supply, and an input voltage of the size of Vref can be input from the input port. The negative input end of the amplification circuit 11 is connected to the first end of the first switch tube M1. The output end of the amplification circuit 11 is connected to the control end of the first switch tube M1. The first end of the first switch tube M1 is also connected to the first current source S1. The current mirror circuit 12 is connected to the second current source S2. When the current conveyor 10 is normally operated, the amplification circuit 11 makes the voltage Vs at the first end of the first switch tube M1 follow Vref, that is, Vs = Vref, so the current value flowing through the third resistor T3 is R3 is the resistance value of the third resistor T3. The current value I7 flowing through the current mirror circuit 12 is I7 = N*(I1+Is), and then the current value Id flowing through the first resistor T1 at the first output end of the current conveyor 10 is:

[0099] Id = I7-I2 = N*(I1+Is)-N*I1 = N*Is

[0100] wherein N is a preset multiple, I1 is the current value of the first current source S1, I2 is the second current value of the second current source S2, Id is the output current value of the first output end of the current conveyor 10, and Is is the output current value of the second output end of the current conveyor 10. That is, the current conveyor 10 realizes the characteristic that Id and Is follow the proportion N.

[0101] It should be pointed out that the specific type of the first switch tube M1 is not unique, and in an embodiment, it is a MOS tube (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET). More specifically, the first switch tube M1 is an NMOS tube, the first end of the first switch tube M1 is the source end of the NMOS tube, the second end of the first switch tube M1 is the drain of the NMOS tube, and the control end of the first switch tube M1 is the gate of the NMOS tube.

[0102] Please refer to Figure 9In one embodiment, the amplification circuit 11 comprises a second switch tube M2, a third switch tube M3, a fourth switch tube M4, a fifth switch tube M5 and a third current source S3; the control end of the second switch tube M2 is connected to an input power source (i.e. Vref), the first end of the second switch tube M2 is connected to the first end of the third switch tube M3, and the common end is connected to the third current source S3, which is grounded; the control end of the third switch tube M3 is connected to the first end of the first switch tube M1, the second end of the third switch tube M3 is connected to the first end of the fifth switch tube M5 and the control end of the first switch tube M1, the second end of the fifth switch tube M5 is connected to the current mirror circuit 12 and a power source; the second end of the second switch tube M2 is connected to the first end of the fourth switch tube M4, the second end of the fourth switch tube M4 is connected to the second end of the fifth switch tube M5, and the control end of the fourth switch tube M4 is connected to the control end of the fifth switch tube M5 and the first end of the fourth switch tube M4.

[0103] Specifically, in this scheme, the control end of the second switch tube M2 is taken as the positive phase input end, the control end of the third switch tube M3 is taken as the negative phase input end, the common end formed by the second end of the third switch tube M3 and the first end of the fifth switch tube M5 is taken as the output end (i.e. point A in the figure) of the amplification circuit 11, and is connected to the control end of the first switch tube M1; the positive phase input end is connected to an input power source, and the input voltage with a size of Vref is input. Through the following characteristics of the amplification circuit 11, the voltage at the first end of the first switch tube M1 (i.e. the voltage at point S) can follow Vref.

[0104] It can be understood that the specific types of the second switch tube M2, the third switch tube M3, the fourth switch tube M4 and the fifth switch tube M5 are not unique, as long as they can realize the above-mentioned voltage following function. For example, in one embodiment, the second switch tube M2, the third switch tube M3, the fourth switch tube M4 and the fifth switch tube M5 can all be set as MOS tubes, and the second switch tube M2 and the third switch tube M3 are MOS tubes of the same type, and the fourth switch tube M4 and the fifth switch tube M5 are MOS tubes of the same type. Further, in a more detailed embodiment, the second switch tube M2 and the third switch tube M3 are NMOS tubes, and the fourth switch tube M4 and the fifth switch tube M5 are PMOS tubes.

[0105] Please refer to Figure 9In one embodiment, the current mirror circuit 12 comprises a sixth switch tube M6 and a seventh switch tube M7, the first end of the sixth switch tube M6 is connected to the second end of the first switch tube Ml, the control end of the sixth switch tube M6 is connected to the first end of the sixth switch tube M6 and the control end of the seventh switch tube M7, the second end of the sixth switch tube M6 is connected to the amplification circuit 11 and the power supply, the second end of the seventh switch tube M7 is connected to the second end of the sixth switch tube M6, and the first end of the seventh switch tube M7 is connected to the second current source S2 and the first end of the first resistor Tl.

[0106] Specifically, in the scheme of this embodiment, the current mirror circuit 12 comprises a sixth switch tube M6 and a seventh switch tube M7, and the size of the single seventh switch tube M7 is the same as that of the sixth switch tube M6, and the number of the seventh switch tube M7 is N times that of the sixth switch tube M6, so as to ensure that the current output at the common end of the seventh switch tube M7 and the second current source S2 is N times that of the second end of the first switch tube Ml.

[0107] Similarly, the specific types of the sixth switch tube M6 and the seventh switch tube M7 are not unique, and in one embodiment, the sixth switch tube M6 and the seventh switch tube M7 can be both set as MOS tubes, and the specific models of the two are the same. For example, in a more detailed embodiment, the sixth switch tube M6 and the seventh switch tube M7 can be both set as PMOS tubes.

[0108] The size of the preset multiple is not unique, and based on different current transmission devices 10 structures, the preset multiple will also be different. In order to facilitate understanding, the following will be described by taking the case that the amplification circuit 11 comprises a second switch tube M2, a third switch tube M3, a fourth switch tube M4, a fifth switch tube M5 and a third current source S3, and the current mirror circuit 12 comprises a sixth switch tube M6 and a seventh switch tube M7, and each switch tube is a MOS tube.

[0109] In this case, the setting of the preset multiple usually has three aspects of consideration. Firstly, the voltage drop on the first resistor Tl is Vd = Id * Rl, assuming that the power supply voltage of the circuit is VDD, then the drain-source voltage Vds7 of the seventh switch tube M7 is VDD-Vd, the gate-source voltage Vgs7 of the seventh switch tube M7 is Vgs7, and the threshold voltage Vth7 of the seventh switch tube M7. In order to ensure that the current mirror composed of the sixth switch tube M6 and the seventh switch tube M7 works normally, it is required that Vds7≥Vgs7-Vth7, that is, Vd≤VDD-(Vgs7-Vth7), which is the first factor limiting the upper limit of Vd. The resistance value of the first resistor Tl is different, and the size of Id is also different, thus limiting Id and further limiting the value of the preset multiple N.

[0110] Secondly, as the input of the ADC in the control device 40, Vd must be within the input range of the ADC, and different ADCs have different input ranges, which should be considered in practice, and will limit the value of the preset multiple N to some extent. Thirdly, the touch display chip usually hopes to have lower power consumption as much as possible, and considering the reduction of power consumption, Id is expected to be as small as possible under the condition of meeting the demand, which also limits the value of the preset multiple N to some extent. In the actual design process, the preset multiple N can be flexibly selected under the condition of meeting the above three conditions.

[0111] In the above touch electrode short circuit detection system, each touch electrode is connected to a negative voltage power supply through a switching device 30, and each touch electrode is also connected to a multiplexer 20. When the touch electrode is detected for short circuit, the multiplexer 20 is used to select the touch electrode to be tested for short circuit verification, so that the touch electrode to be tested is connected to the second output end of the current transmitter 10 through the multiplexer 20 and the second resistor T2. First, when the switching device 30 corresponding to the touch electrode to be tested is turned on, the first output end of the current transmitter 10 is collected for voltage when the touch electrode to be tested is connected to the negative voltage power supply, and a first voltage sampling value is obtained. Then, when the switching device 30 corresponding to the touch electrode to be tested is turned off, the first output end of the current transmitter 10 is collected for voltage when the connection between the touch electrode to be tested and the negative voltage power supply is disconnected, and a second voltage sampling value is obtained. Then, the equivalent resistance value of the touch electrode to be tested can be obtained by combining the first voltage sampling value and the second voltage sampling value. Finally, the short circuit verification of the touch electrode to be tested is completed by comparing the equivalent resistance value with a preset resistance threshold. The above scheme can realize the short circuit detection of the touch electrode by using a simple circuit structure. When the touch electrode has a short circuit fault, the fault can be found out in time, so that relevant fault repair processing can be performed. The display device can avoid touch display in the short circuit state of the touch electrode, and effectively alleviate the problem of low touch accuracy of the display device caused by the short circuit of the touch electrode.

[0112] A display device includes the above touch electrode short circuit detection system.

[0113] Specifically, the display device further includes a display panel and a chip (such as a TDDI chip) for touch display. The touch electrode short circuit detection system is as shown in the above embodiments and the accompanying drawings, and is integrated in the internal of the touch display chip. No additional detection circuit design is needed for the screen module, the touch screen module scheme is simplified, the chip area is not significantly increased, and the cost of the touch display chip is reduced. Meanwhile, the scheme has the advantages of fast detection speed and high detection precision, and basically does not affect the screen display during short circuit detection. Further, the display device provided by the present application can also be applied to devices with touch display requirements such as mobile phones, tablet computers, air conditioners, and automobiles.

[0114] Any combination of the technical features in the above-described embodiments can be made, and for the sake of brevity, not all possible combinations are described, however, it is to be understood that the application embraces all such possible combinations.

[0115] The above-described embodiments only express several implementation manners of the application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the application. It should be pointed out that, for ordinary skilled persons in the art, some modifications and improvements can be made without departing from the concept of the application, and these all belong to the protection scope of the application. Therefore, the patent protection scope of the application should be subject to the appended claims.

Claims

1. A method for detecting short circuits in touch electrodes, characterized in that, include: When the touch electrode under test is connected to a negative voltage power supply, the first voltage sampling value of the first output terminal of the current transmitter is obtained. The first output terminal of the current transmitter is grounded through a first resistor, the second output terminal of the current transmitter is connected to a multiplexer through a second resistor, the input terminal of the current transmitter is connected to an input power supply, each of the touch electrodes is connected to the multiplexer, each of the touch electrodes is connected to the negative voltage power supply through a switching device, and the touch electrode under test is selected by the multiplexer and then connected to the touch electrode of the second output terminal of the current transmitter through the second resistor; When the touch electrode under test is not connected to the negative voltage power supply, and all other touch electrodes are connected to the negative voltage power supply, the second voltage sampling value of the first output terminal of the current transmitter is obtained; The equivalent resistance value of the touch electrode under test is obtained based on the first voltage sampling value, the second voltage sampling value, and the preset equivalent resistance calculation model. The touch electrode under test is short-circuited based on the equivalent resistance value and the preset resistance threshold.

2. The short-circuit detection method for touch electrodes according to claim 1, characterized in that, The output current at the first output terminal of the current transmitter is a preset multiple of the output current at the second output terminal of the current transmitter. Before obtaining the equivalent resistance value of the touch electrode under test based on the first voltage sampling value, the second voltage sampling value, and the preset equivalent resistance calculation model, the method further includes: Based on the preset multiple, the resistance value of the first resistor, the voltage of the input power supply, the voltage of the negative voltage power supply, and the output voltage parameters of the first output terminal of the current transmitter when the touch electrode under test is connected to and not connected to the negative voltage power supply, a preset equivalent resistance calculation model is obtained.

3. The short-circuit detection method for touch electrodes according to claim 2, characterized in that, The preset equivalent resistance calculation model is obtained based on the preset multiple, the resistance value of the first resistor, the voltage of the input power supply, the voltage of the negative voltage power supply, and the output voltage parameters of the first output terminal of the current transmitter when the touch electrode under test is connected to and not connected to the negative voltage power supply, including: The first resistance model is obtained based on the preset multiple, the resistance value of the first resistor, the voltage of the input power supply and the voltage of the negative voltage power supply, and the output voltage parameter of the first output terminal of the current transmitter when the touch electrode under test is connected to the negative voltage power supply. The second resistance model is obtained based on the preset multiple, the resistance value of the first resistor, the voltage of the input power supply and the voltage of the negative voltage power supply, and the output voltage parameters of the first output terminal of the current transmitter when the touch electrode under test is not connected to the negative voltage power supply. Based on the first resistance model and the second resistance model, a preset equivalent resistance calculation model is obtained; And / or, the step of short-circuit verification of the touch electrode under test based on the equivalent resistance value and a preset resistance threshold includes: When the equivalent resistance value is less than or equal to the preset resistance threshold, the verification result of the short circuit of the touch electrode under test is obtained. When the equivalent resistance value is greater than the preset resistance threshold, the verification result is that the touch electrode under test has not been short-circuited.

4. The short-circuit detection method for touch electrodes according to any one of claims 1-3, characterized in that, After performing short-circuit verification on the touch electrode under test based on the equivalent resistance value and the preset resistance threshold, the method further includes: Determine whether all of the aforementioned touch electrodes have completed the short-circuit verification; If there is a touch electrode that has not completed short-circuit verification, the multiplexer is controlled to select the next touch electrode that has not completed short-circuit verification as the touch electrode to be tested, and the process returns to the step of obtaining the first voltage sampling value of the first output terminal of the current transmitter when the touch electrode to be tested is connected to a negative voltage power supply, until all the touch electrodes have completed short-circuit verification.

5. The short-circuit detection method for touch electrodes according to claim 4, characterized in that, The determination of whether each of the touch electrodes has completed the short-circuit verification includes: The number of verification attempts is accumulated to obtain the number of touch electrodes that have completed short-circuit verification; if the number is less than a preset threshold, it is considered that there are touch electrodes that have not completed short-circuit verification.

6. A short-circuit detection system for touch electrodes, characterized in that, include: A current transmitter, the input terminal of which is connected to an input power supply; A first resistor, the first end of which is connected to the first output terminal of the current transmitter, and the second end of which is grounded; Second resistor; A multiplexer, wherein the multiplexer is connected to the second output terminal of the current transmitter via the second resistor; A switching device is provided, and each touch electrode is connected to the multiplexer. Each touch electrode is connected to a negative voltage power supply through one of the switching devices. A control device is provided, wherein the control device is connected to the first terminal of the first resistor, the multiplexer and each of the switching devices are respectively connected to the control device, and the control device is used to perform short-circuit verification on each of the touch electrodes according to any one of claims 1-5.

7. The touch electrode short-circuit detection system according to claim 6, characterized in that, The current transmitter includes an amplifier circuit, a current mirror circuit, a first switching transistor, a third resistor, a first current source, and a second current source. The current value of the second current source is a preset multiple of the current value of the first current source. The amplifier circuit is connected to the input power supply and the current mirror circuit is connected to the power supply. The current mirror circuit is connected to the second terminal of the first switching transistor and the control terminal of the first switching transistor. The first terminal of the first switching transistor is connected to the first current source, the first terminal of the third resistor, and the amplifier circuit. The second terminal of the third resistor is grounded. The first terminal of the first switching transistor is connected to the multiplexer through the second resistor. The current mirror circuit is connected to the second current source and the first terminal of the first resistor. The amplifier circuit, the first current source, and the second current source are all grounded.

8. The touch electrode short-circuit detection system according to claim 7, characterized in that, The amplifier circuit includes a second switch, a third switch, a fourth switch, a fifth switch, and a third current source. The control terminal of the second switch is connected to the input power supply. The first terminal of the second switch is connected to the first terminal of the third switch, and their common terminal is connected to the third current source, which is grounded. The control terminal of the third switch is connected to the first terminal of the first switch. The second terminal of the third switch is connected to the first terminal of the fifth switch and the control terminal of the first switch. The second terminal of the fifth switch is connected to the current mirror circuit and the power supply. The second terminal of the second switch is connected to the first terminal of the fourth switch. The second terminal of the fourth switch is connected to the second terminal of the fifth switch. The control terminal of the fourth switch is connected to the control terminal of the fifth switch and the first terminal of the fourth switch.

9. The touch electrode short-circuit detection system according to claim 7, characterized in that, The current mirror circuit includes a sixth switch and a seventh switch. The first end of the sixth switch is connected to the second end of the first switch. The control end of the sixth switch is connected to the first end of the sixth switch and the control end of the seventh switch. The second end of the sixth switch is connected to the amplifier circuit and the power supply. The second end of the seventh switch is connected to the second end of the sixth switch. The first end of the seventh switch is connected to the second current source and the first end of the first resistor.

10. A display device, characterized in that, The system includes the touch electrode short-circuit detection system according to any one of claims 6-9.

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