Capacitive screen repairing circuit

Abstract

The invention relates to the technical field of capacitive screens, in particular to a capacitive screen repairing circuit which comprises a control unit, a power management module, an in-phase amplification unit, a reverse-phase amplification unit and a feedback module. The output end of the power management module is connected with the input ends of the in-phase amplification unit and the reverse-phase amplification unit. According to the capacitive screen repairing circuit, abnormal capacitance on the capacitive touch screen can be repaired, the repairing efficiency is high, burrs of the capacitive touch screen are repaired by applying high voltage to the capacitive touch screen, and when the current obtained by the feedback module does not exceed the current preset value, it is judged that repairing is completed, and the repairing efficiency is high. The output voltage of the power management module is reduced, so that the capacitive touch screen is protected, the screen is prevented from being burnt by continuously applied large voltage, the yield of products is improved, the production cost is reduced, the production speed is increased, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of capacitive touch screens, and specifically to a capacitive touch screen repair circuit. Background Art

[0002] Currently, for capacitive touch screens, it is difficult to detect abnormal conditions of the touch matrix resistance-capacitance, and it is even more difficult to repair the detected faults. When the detection cost and repair cost are too high, the screens with abnormal touch matrix resistance-capacitance will be discarded as defective products, which will cause huge waste, significantly increase the production cost, and delay the production speed. Therefore, improvements are needed. Summary of the Invention

[0003] The purpose of the present invention is to provide a capacitive touch screen repair circuit to solve the problems raised in the above background art.

[0004] To achieve the above purpose, the present invention provides the following technical solution: A capacitive touch screen repair circuit includes a control unit, a power management module, a non-inverting amplification unit, an inverting amplification unit, and a feedback module. The output end of the control unit is connected to the input end of the power management module. The output end of the power management module is respectively connected to the input ends of the non-inverting amplification unit and the inverting amplification unit. The output ends of the non-inverting amplification unit and the inverting amplification unit are respectively connected to the capacitive touch screen. The non-inverting amplification unit and the inverting amplification unit are connected to the feedback module, and the connection output end of the feedback module is connected to the input end of the control unit.

[0005] Preferably, during the process of the output voltage of the power management module increasing, when the current obtained by the feedback module does not exceed the preset current value, which is determined by the capacitive touch screen, the output voltage of the power management module is reduced to 0.

[0006] Preferably, during the process of the output voltage of the power management module increasing, if until the voltage increases to the highest preset voltage value, which is determined by the capacitive touch screen, and the current obtained by the feedback module is still greater than the preset current value, the highest preset voltage value is increased; during the process of the output voltage of the power management module increasing, if until the voltage increases to the highest preset voltage value and the current obtained by the feedback module is still greater than the preset current value, the output voltage of the power management module is reduced.

[0007] Preferably, the feedback module is used to monitor the magnitude of the current during the repair process and feedback this information to the control unit.

[0008] Preferably, the non-inverting amplification unit and the inverting amplification unit are responsible for amplifying the voltage signal output by the power management module, and these amplified signals will be used to repair the burrs on the touch screen;

[0009] The power management module is responsible for providing a stable working voltage and adjusting the magnitude of the output voltage according to the instructions of the control unit. This module needs to be able to output a sufficiently high voltage to repair the glitches on the touch screen.

[0010] Preferably, the feedback module includes:

[0011] A first resistor, which is connected to the non-inverting amplifier and the positive terminal of the capacitive touch screen;

[0012] A second resistor, which is connected to the inverting amplifier and the negative terminal of the capacitive touch screen;

[0013] A differential operational amplifier, whose positive terminal and negative terminal are respectively connected to the first resistor and the second resistor;

[0014] A feedback loop, whose function is to convert the voltage signal at the output terminal of the differential operational amplifier into a digital signal and transmit it to the control module.

[0015] Preferably, the non-inverting amplification unit includes:

[0016] A first amplifier for amplifying the non-inverting voltage signal;

[0017] A third resistor and a fourth resistor for adjusting the amplification factor of the first amplifier.

[0018] Preferably, at the same time, the magnitudes of the non-inverting voltage signal and the inverting voltage signal are the same and their directions are opposite; the amplification factor of the first amplifier is the same as that of the second amplifier.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] A capacitive screen repair circuit proposed by the present invention can repair abnormal capacitances on the capacitive touch screen, and the repair efficiency is high. By applying a high voltage to the capacitive touch screen, the glitches on the capacitive touch screen are repaired. And when the current obtained by the feedback module does not exceed the preset current value, it is determined that the repair is completed, and the output voltage of the power management module is reduced, thereby protecting the capacitive touch screen, avoiding the large voltage continuously applied from burning the screen, improving the yield rate of the product, reducing the production cost, accelerating the production speed, and improving the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is the overall structural schematic diagram of the repair circuit of the present invention.

[0022] Figure 2 It is the connection schematic diagram of the repair circuit of the present invention.

[0023] In the figure: control unit 10, power management module 20, non-inverting amplifier unit 30, feedback module 40, inverting amplifier unit 50, first switch 61, second switch 62. Detailed implementation

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0025] Please refer to Figures 1 to 2 , the present invention provides a technical solution: a capacitive touch screen repair circuit, including a control unit 10, a power management module 20, a non-inverting amplifier unit 30, an inverting amplifier unit 50, and a feedback module 40. The output end of the control unit 10 is connected to the input end of the power management module 20. The output end of the power management module 20 is respectively connected to the input ends of the non-inverting amplifier unit 30 and the inverting amplifier unit 50. The output ends of the non-inverting amplifier unit 30 and the inverting amplifier unit 50 are respectively connected to the capacitive touch screen. The non-inverting amplifier unit 30 and the inverting amplifier unit 50 are connected to the feedback module 40, and the connection output end of the feedback module 40 is connected to the input end of the control unit 10.

[0026] During the process of the output voltage of the power management module 20 increasing, when the current obtained by the feedback module 40 does not exceed the current preset value, the current preset value is determined by the capacitive touch screen, and the output voltage of the power management module 20 is reduced to 0.

[0027] During the process of the output voltage of the power management module 20 increasing, if until the voltage increases to the highest voltage preset value, the highest voltage preset value is determined by the capacitive touch screen, and the current obtained by the feedback module 40 is still greater than the current preset value, the highest voltage preset value is increased; during the process of the output voltage of the power management module 20 increasing, if until the voltage increases to the highest voltage preset value and the current obtained by the feedback module 40 is still greater than the current preset value, the output voltage of the power management module 20 is reduced.

[0028] The feedback module 40 is used to monitor the magnitude of the current during the repair process and feed this information back to the control unit 10, so that the control unit 10 can adjust the output voltage according to the feedback to ensure the safety and effectiveness of the repair process.

[0029] The non-inverting amplifier unit 30 and the inverting amplifier unit 50 are responsible for amplifying the voltage signals output by the power management module 20, and these amplified signals will be used to repair the burrs on the touch screen;

[0030] The power management module 20 is responsible for providing a stable working voltage and adjusting the magnitude of the output voltage according to the instructions of the control unit 10. This module needs to be able to output a high enough voltage to repair the burrs on the touch screen.

[0031] The feedback module 40 includes:

[0032] The first resistor R1, which is connected to the non-inverting amplification unit 30 and the positive terminal of the capacitive touch screen;

[0033] The second resistor R2, which is connected to the inverting amplification unit 50 and the negative terminal of the capacitive touch screen;

[0034] The differential operational amplifier, whose positive terminal and negative terminal are respectively connected to the first resistor R1 and the second resistor R2;

[0035] The feedback loop, whose function is to convert the voltage signal at the output terminal of the differential operational amplifier U1 into a digital signal and transmit it to the control unit 10.

[0036] The non-inverting amplification unit 30 includes:

[0037] The first amplifier APM1, which is used to amplify the non-inverting voltage signal;

[0038] The third resistor R3 and the fourth resistor R4, which are used to adjust the amplification factor of the first amplifier APM1.

[0039] The inverting amplification unit 50 includes:

[0040] The second amplifier APM2, which is used to amplify the inverting voltage signal;

[0041] The fifth resistor R5 and the sixth resistor R6, which are used to adjust the amplification factor of the second amplifier APM2.

[0042] At the same time, the magnitudes of the non-inverting voltage signal and the inverting voltage signal are the same and the directions are opposite; the amplification factor of the first amplifier APM1 is the same as that of the second amplifier APM2.

[0043] In actual use, the control unit 10 outputs a control signal to the power management module 20 to control the magnitude of the voltage output by the power management module 20. The voltage signals output by the power management module 20 are amplified by the in-phase amplification unit 30 and the in-phase amplification unit 50 respectively, and then the capacitive touch screen is repaired. The feedback module 40 is used to detect the magnitude of the current during the repair process of the capacitive touch screen and feed the result back to the control unit 10, so that the control unit 10 controls the voltage during the repair process of the capacitive touch screen in a closed-loop form. When repairing the burrs on the capacitive screen, large-current burrs need to be melted. The in-phase amplification unit 30 and the in-phase amplification unit 50 can improve the output current capacity of the power management module 20, increase the output currents of the in-phase amplification unit 30 and the in-phase amplification unit 50, and can efficiently remove burrs. Specific embodiments:

[0045] The power management module 20 increases the current. When the current obtained by the feedback module 40 does not exceed the preset value, the output voltage of the power management module 20 decreases.

[0046] Both the current preset value and the voltage preset value can be determined according to the capacitive screen. For capacitive screens of the same model and the same specification, the same current preset value and voltage preset value can be set. If there are more burrs or they are more difficult to remove, the voltage preset value and the voltage preset value can also be increased accordingly. After the current preset value and the voltage preset value are set, the preset values should be set in advance for capacitive screens of the same model and the same batch.

[0047] The capacitance preset value can correspond to the magnitude of the current required when all ideal burrs are removed. At this time, the entire capacitive touch screen will not be short-circuited due to burrs. The current preset value can also correspond to artificially set indicators. For example, a certain type of burr is specifically filtered to achieve a certain indicator.

[0048] After the current increases, the originally connected burrs, due to their own burr resistance, are melted by the high temperature generated by the sudden increase in current, so as to achieve the purpose of removing burrs and complete the repair of the capacitive touch screen.

[0049] When the voltage keeps increasing until all burrs are removed, the current will decrease to the preset value or be lower than the preset value. At this time, it is judged that the repair is completed, and the output voltage of the power management module 20 decreases.

[0050] When the current obtained by the feedback module 40 is equal to the current preset value during the voltage increase process of the power management module 20, the output voltage of the power management module 20 drops to zero. At this time, the power management module 20 completely stops pressurizing the capacitive touch screen, which can play a role in protecting the capacitive touch screen.

[0051] In another embodiment, during the process of the output voltage of the power management module 20 rising, if until the voltage rises to the highest preset voltage value, the current obtained by the feedback module 40 is still greater than the preset current value, the highest preset voltage value is increased. The corresponding scenario at this time is: when repairing multiple capacitive touchscreens of the same batch, all or most of the capacitive touchscreens cannot complete the repair process. At this time, it is judged that the set highest preset voltage value is insufficient to completely repair the short circuit, and the highest preset voltage value needs to be further increased to possibly complete the repair of more capacitive touchscreens.

[0052] In other embodiments, during the process of the output voltage of the power management module 20 rising, if until the voltage rises to the highest preset voltage value, the current obtained by the feedback module 40 is still greater than the preset current value, the output voltage of the power management module 20 is decreased. The corresponding scenario at this time is: until the voltage rises to the highest preset voltage value and the current has not reached the preset current value, indicating that the fault cannot be eliminated. At this time, this capacitive touchscreen is judged as a defective product that is difficult to repair, to avoid damaging other components due to continuously increasing the voltage.

[0053] Refer to Figure 2 Introduce the circuit;

[0054] The power management module 20 includes:

[0055] A first voltage management unit PUM1 that outputs a common-phase voltage and a second voltage management unit PUM2 that outputs an inverted-phase voltage; the first power management unit PUM1 and the second voltage management unit PUM2 can adjust the voltage output magnitude by the control unit 10.

[0056] The common-phase amplification unit 30 includes: a first amplifier APM1 that amplifies the common-phase voltage signal and a third resistor R3 and a fourth resistor R4 for adjusting the amplification factor.

[0057] The inverting amplification unit 50 includes: a second amplifier APM2 that amplifies the inverting voltage signal and a fifth resistor R5 and a sixth resistor R6 for adjusting the amplification factor.

[0058] The feedback module 40 includes: a first resistor R1, the first resistor R1 is connected to the common-phase amplification unit 30 and the positive end of the capacitive touchscreen; a second resistor R2, the second resistor R2 is connected to the inverting amplification unit 50 and the negative end of the capacitive touchscreen; a differential operational amplifier U1, whose positive end and negative end are respectively connected to the first resistor R1 and the second resistor R2; a feedback loop, whose function is to convert the voltage signal at the output end of the differential operational amplifier U1 into a digital signal and transmit it to the control unit 10; an analog-to-digital converter ADC1, which is used to convert the analog voltage signal at the output end of the differential operational amplifier U1 into a digital voltage signal and transmit it to the control module 10.

[0059] The first switch 61 and the second switch 62, the first switch 61 is connected between the first resistor R1 and the positive terminal of the capacitive touch screen, and the second switch 62 is connected between the second resistor R2 and the negative terminal of the capacitive touch screen. The opening and closing of the circuit are controlled by the two switches.

[0060] The repair circuit can repair the abnormal capacitance on the capacitive touch screen, and the repair efficiency is high. By applying a high voltage to the capacitive touch screen, the burrs on the capacitive touch screen are repaired. When the current obtained by the feedback module 40 does not exceed the preset current value, it is determined that the repair is completed, and the output voltage of the power management module 20 is reduced, thereby protecting the capacitive touch screen, avoiding the screen being burned by the continuously applied large voltage, improving the yield rate of the product, reducing the production cost, accelerating the production speed, and improving the production efficiency.

[0061] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A capacitive screen repair circuit, characterized in that: The invention comprises a control unit, a power management module, a common-phase amplification unit, an inverting amplification unit and a feedback module, wherein the output end of the control unit is connected to the input end of the power management module, the output end of the power management module is respectively connected to the input ends of the common-phase amplification unit and the inverting amplification unit, the output ends of the common-phase amplification unit and the inverting amplification unit are respectively connected to the capacitive touch screen, the common-phase amplification unit and the inverting amplification unit are connected to the feedback module, and the connection output end of the feedback module is connected to the input end of the control unit.

2. The capacitive screen repair circuit according to claim 1, characterized in that: During the process of increasing the output voltage of the power management module, when the current acquired by the feedback module does not exceed the preset current value, which is determined by the capacitive screen, the output voltage of the power management module is reduced to 0.

3. The capacitive screen repair circuit according to claim 1, characterized in that: During the process of increasing the output voltage of the power management module, if until the voltage rises to the maximum preset voltage value, which is determined by the capacitive screen, the current obtained by the feedback module is still greater than the current preset value, the maximum preset voltage value is increased; during the process of increasing the output voltage of the power management module, if until the voltage rises to the maximum preset voltage value, the current obtained by the feedback module is still greater than the current preset value, the output voltage of the power management module is reduced.

4. The capacitive screen repair circuit according to claim 1, characterized in that: The feedback module is used to monitor the current size during the repair process and feed back this information to the control unit, so that the control unit can adjust the output voltage according to the feedback to ensure the safety and effectiveness of the repair process.

5. The capacitive screen repair circuit according to claim 1, characterized in that: The in-phase amplifier unit and the inverting amplifier unit are responsible for amplifying the voltage signal output by the power management module, and these amplified signals will be used to repair the burrs of the touch screen; The power management module is responsible for providing a stable operating voltage and adjusting the output voltage according to the instructions of the control unit. This module needs to be able to output a sufficiently high voltage to repair the burrs on the touch screen.

6. The capacitive screen repair circuit according to claim 1, characterized in that: The feedback module comprises: A first resistor, wherein the first resistor is connected to the in-phase amplifier and to a positive terminal of the capacitive touch screen; A second resistor, the second resistor is connected to the inverting amplifier and the negative terminal of the capacitive touch screen; A differential operational amplifier, a positive terminal and a negative terminal of which are connected to the first resistor and the second resistor respectively; The feedback loop is used to convert the voltage signal at the output of the differential operational amplifier into a digital signal and transmit it to the control module.

7. The capacitive screen repair circuit according to claim 1, characterized in that: The in-phase amplification unit comprises: A first amplifier, used for amplifying the same-direction voltage signal; The third resistor and the fourth resistor are used to adjust the amplification factor of the first amplifier.

8. The capacitive screen repair circuit according to claim 1, characterized in that: The inverting amplification unit comprises: A second amplifier, used to amplify the reverse voltage signal; The fifth resistor and the sixth resistor are used to adjust the amplification factor of the second amplifier.

9. The capacitive screen repair circuit according to claim 8, characterized in that: At the same time, the voltage magnitudes of the same-direction voltage signal and the reverse-direction voltage signal are the same, but the directions are opposite; and the amplification factor of the first amplifier is the same as the amplification factor of the second amplifier.

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