Source driver, display device and flexible circuit board

Abstract

The utility model provides a source driver, a display device and a flexible circuit board, relates to the technical field of display, and aims to enhance the electrostatic protection capability and prevent the problems of electrostatic discharge splash screen and the like. The source driver includes a digital circuit, an analog circuit, and a protection circuit. Wherein the digital circuit is configured to receive a first voltage signal and output an enable control signal. The analog circuit is electrically connected with the digital circuit, and the analog circuit is configured to receive the enable control signal and the second voltage signal and output a clock control signal. The protection circuit is electrically connected with the digital circuit and the analog circuit, and the protection circuit is configured to control a voltage difference to be smaller than a threshold voltage under the condition that the first voltage signal and the second voltage signal generate the voltage difference. Based on this, when static attacks the ground signal, the voltage difference between the digital ground signal and the analog ground signal does not affect the digital logic operation, thereby ensuring the accuracy of the signal logic of the source electrode driver, and improving the antistatic capability of the source electrode driver.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a source driver, a display device and a flexible circuit board. BACKGROUND

[0002] With the development of technology, the wafer manufacturing process is gradually reduced. Taking the field of display technology as an example, the driving process of the active matrix organic light emitting diode (AMOLED) is mainly 28 / 40nm, but with the gradual increase of market requirements for the performance, power consumption and size of the driver, the research and development of 22 / 16nm process is also on the agenda.

[0003] However, the smaller the process is, the weaker the electrostatic protection ability of the driver is, and the problem of electrostatic discharge flash screen is prone to occur. UTILITY MODEL CONTENT

[0004] The present application provides a source driver, a display device, a flexible circuit board and a display device, which aims to improve the anti-static ability of the device.

[0005] To achieve the above purpose, the embodiments of the present application provide the following technical solutions:

[0006] In a first aspect, a source driver is provided, comprising a digital circuit, an analog circuit and a protection circuit. The digital circuit is configured to receive a first voltage signal and output an enable control signal. The analog circuit is electrically connected to the digital circuit, and the analog circuit is configured to receive the enable control signal and a second voltage signal and output a clock control signal. The protection circuit is electrically connected to the digital circuit and the analog circuit, and the protection circuit is configured to control the voltage difference to be less than a threshold voltage when a voltage difference between the first voltage signal and the second voltage signal is generated.

[0007] In some embodiments, the protection circuit includes a buffer sub-circuit and a switch sub-circuit. The buffer sub-circuit is electrically connected to the digital circuit and the analog circuit, and the switch sub-circuit is electrically connected to the digital circuit and the analog circuit. The switch sub-circuit is configured to be turned on when the voltage difference is greater than or equal to the threshold voltage, so that the buffer sub-circuit controls the voltage difference to be less than the threshold voltage.

[0008] In some embodiments, the protection circuit includes one capacitor and two diodes. The first end of the capacitor is electrically connected to the digital circuit, and the second end of the capacitor is electrically connected to the analog circuit. Among the two diodes, the first electrode of one diode is electrically connected to the first end of the capacitor, and the second electrode is electrically connected to the second end of the capacitor. The first electrode of the other diode is electrically connected to the second end of the capacitor, and the second electrode is electrically connected to the first end of the capacitor.

[0009] In some embodiments, the threshold voltage is a turn-on voltage of the diode.

[0010] In some embodiments, the digital circuit includes a first sub-circuit configured to output a digital control signal, and a first operational amplifier circuit electrically connected to the first sub-circuit and configured to receive the digital control signal and a first voltage signal and output an enable control signal. The analog circuit includes a second operational amplifier circuit configured to receive the enable control signal and a second voltage signal and output an analog control signal, and a second sub-circuit electrically connected to the second operational amplifier circuit and configured to output a clock control signal under control of the analog control signal.

[0011] In the embodiments of the present application, the digital circuit is configured to receive a first voltage signal, and the analog circuit is configured to receive a second voltage signal. When an electrostatic attack occurs on the ground, due to the existence of resistances of different sizes in the discharge path, the first voltage signal (for example, a digital ground DVSS signal) and the second voltage signal (for example, an analog ground VSS OSC signal) will produce different voltage drops during transmission, thereby causing a voltage difference between the first voltage signal and the second voltage signal. This will cause the ground signals of the digital circuit and the analog circuit to be disturbed, thereby causing the signal judgment reference to be inconsistent during system operation, which can easily affect the digital logic operation and cause the problem of false touch operation.

[0012] The protection circuit is configured to control the voltage difference to be less than the threshold voltage in the case that the voltage difference between the first voltage signal and the second voltage signal is generated. That is, the protection circuit is configured to control the voltage difference to be within a range below the threshold voltage. In this case, the voltage difference between the digital ground signal and the analog ground signal will not affect the digital logic operation, thereby ensuring the accuracy of the source driver signal logic and improving the anti-static capability of the source driver.

[0013] In a second aspect, the present application further provides a display device including the source driver and the display panel in any one of the embodiments of the first aspect.

[0014] The display device has the same technical effects as the above-mentioned source driver, and details are not repeated here.

[0015] In a third aspect, the present application further provides a flexible circuit board including a first power line, a second power line, and a protection circuit. The first power line is configured to transmit a first voltage signal, the second power line is configured to transmit a second voltage signal, and the protection circuit is electrically connected to the first power line and the second power line and is configured to control a voltage difference to be less than a threshold voltage in the case that the voltage difference between the first voltage signal and the second voltage signal is generated.

[0016] In some embodiments, the protection circuit includes a buffer sub-circuit and a switch sub-circuit. The buffer sub-circuit is electrically connected to the first power line and the second power line, and the switch sub-circuit is electrically connected to the first power line and the second power line. The switch sub-circuit is configured to be turned on when the voltage difference is greater than or equal to the threshold voltage, so that the buffer sub-circuit controls the voltage difference to be less than the threshold voltage.

[0017] In some embodiments, the protection circuit includes a capacitor and two diodes. The first end of the capacitor is electrically connected to the first power line, and the second end of the capacitor is electrically connected to the second power line. Among the two diodes, the first electrode of one diode is electrically connected to the first end of the capacitor, and the second electrode is electrically connected to the second end of the capacitor. The first electrode of the other diode is electrically connected to the second end of the capacitor, and the second electrode is electrically connected to the first end of the capacitor.

[0018] In some embodiments, the threshold voltage is the turn-on voltage of the diode.

[0019] In the embodiments of the present application, the first power line is used to transmit the first voltage signal, and the second power line is used to transmit the second voltage signal. When the electrostatic attack attacks the ground, due to the existence of resistances of different sizes in the discharge path, the first voltage signal (for example, the digital ground DVSS signal) on the first power line and the second voltage signal (for example, the digital ground DVSS signal) on the second power line will produce different voltage drops during transmission, thereby causing a voltage difference between the first voltage signal and the second voltage signal, and causing the ground signal of the digital circuit and the analog circuit in the source driver to be disturbed. This will cause the signal judgment reference to be inconsistent during system operation, which will easily affect the digital logic operation and cause the problem of false touch operation.

[0020] The protection circuit can control the voltage difference to be less than the threshold voltage when the first voltage signal and the second voltage signal produce a voltage difference. That is, the protection circuit is used to control the voltage difference to be within a range below the threshold voltage. In this case, the voltage difference between the digital ground signal and the analog ground signal will not affect the digital logic operation, ensuring the accuracy of the system signal logic, thereby improving the anti-static capability of the system.

[0021] In a fourth aspect, the present application also provides a display device, which includes the flexible circuit board in any one of the embodiments of the third aspect and a display panel, and the flexible circuit board is electrically connected to the display panel.

[0022] The display device has the same technical effects as the above-mentioned flexible circuit board, which will not be described here again. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the present application, the following will briefly introduce the drawings needed to be used in some embodiments of the present application. Obviously, the drawings described in the following description are only some of the drawings of the embodiments of the present application, and other drawings can also be obtained by those skilled in the art according to these drawings. In addition, the drawings in the following description can be regarded as schematic drawings, and are not the actual size of the product involved in the embodiments of the present application, or the actual process of the method.

[0024] Figure 1 A circuit structure schematic diagram of a source driver provided for an embodiment of the present application;

[0025] Figure 2 A discharge path schematic diagram when electrostatic attack ground provided for an embodiment of the present application;

[0026] Figure 3 A structure schematic diagram of a display device provided for an embodiment of the present application;

[0027] Figure 4 A structure schematic diagram of a flexible circuit board provided for an embodiment of the present application;

[0028] Figure 5 A structure schematic diagram of another display device provided for an embodiment of the present application. DETAILED DESCRIPTION

[0029] The technical solutions in some embodiments of the present application will be described clearly and completely below in combination with the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments provided in the present application, all other embodiments obtained by those skilled in the art belong to the scope of protection of the present application.

[0030] Unless otherwise required by the context, the term "comprising" is to be interpreted as open, inclusive meaning, i.e. "including, but not limited to".

[0031] Hereinafter, the terms "first", "second" are only used for description purpose, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more features. In the description of the embodiments of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0032] In describing some embodiments, use is made of the term "connected" and its derivatives. The term "connected" is used broadly and essentially means connected directly or indirectly. For example, when used in the context of two or more components being connected together, "connected" can be used to indicate that the two or more components are in direct physical or electrical contact with each other, or that there exists an intervening medium between the two or more components.

[0033] In addition, use of "based on" means open and inclusive, as "based on" one or more stated conditions or values can mean based on those conditions or values and others that are not stated.

[0034] It will be understood that when a layer or element is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate or intervening layers can also be present.

[0035] Exemplary embodiments are described herein with reference to cross-sectional illustrations that are idealized examples. In the drawings, the thickness of layers and regions are exaggerated for clarity. Accordingly, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and / or tolerances, are to be expected. Thus, the exemplary embodiments should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, an etched region illustrated as a rectangle will typically have rounded or curved features. Thus, the regions illustrated in the drawings are schematic and their shapes are not intended to illustrate the precise shape of a region that would be formed in a device and are not intended to limit the exemplary embodiments to a precise geometric shape. The exemplary embodiments are therefore to be understood as not being limited to the illustrations described herein and as including variations that result for example from manufacturing.

[0036] With the development of technology, the wafer manufacturing process is gradually reduced. The smaller the process is, the weaker the electrostatic protection ability inside the driver is, and the more difficult the design of the electrostatic impact resistance of the corresponding driver is. At present, the protection design of the electrostatic resistance of the driver is basically based on the protection design of the static impact falling on the high or low level signal itself, ignoring the ground potential disorder caused by the static attack of the ground signal. Ground potential disorder can cause system signal logic error. In the related art, the above problem is alleviated by continuously increasing the area of the ground plate, and there is a lack of a special protection circuit for avoiding the electrostatic discharge flash screen and other problems caused by the static attack of the ground signal.

[0037] To solve the above problems, the application provides a source driver, as shown in Figure 1 Figure 1 A circuit structure schematic diagram of a source driver provided by the embodiment of the application.

[0038] ​The source driver 1 includes a digital circuit 11, an analog circuit 12, and a protection circuit 13. The digital circuit 11 is configured to receive a first voltage signal D1 and output an enable control signal. The analog circuit 12 is electrically connected to the digital circuit 11 and configured to receive the enable control signal and a second voltage signal D2 and output a clock control signal. The protection circuit 13 is electrically connected to the digital circuit 11 and the analog circuit 12 and configured to control the voltage difference to be less than a threshold voltage when a voltage difference is generated between the first voltage signal D1 and the second voltage signal D2.

[0039] Exemplarily, the first voltage signal D1 received by the digital circuit 11 is a digital ground signal, such as a DVSS signal, and the enable control signal output by the digital circuit 11 is used to control the operating state of the analog circuit 12. The second voltage signal D2 received by the analog circuit 12 is an analog ground signal, such as VSS_OSC, and the clock control signal output by the analog circuit 12 is used to provide a reference clock signal, such as OSC_CLK, for the system.

[0040] When static electricity strikes the system ground, it will cause disturbance of the ground signal inside the source driver 1 , causing a voltage difference between the first voltage signal D1 and the second voltage signal D2 . The mechanism of this difference is described below.

[0041] like Figure 2 As shown, Figure 2 A schematic diagram of the discharge path when static electricity strikes the earth is provided in an embodiment of the present application.

[0042] When static electricity strikes the system ground, it is usually directly input through the copper leakage area 301 on the flexible circuit board 3. Figure 2 As shown in the leakage path L1, most of the energy can be discharged directly through the ground plane GND of the flexible circuit board 3 through the connector 14. Figure 2 As shown in the leakage path L2, due to the block design of the ground plate GND of the flexible circuit board 3, there are resistances of different sizes between the ground plates GND connected together through vias and ground wires. This will cause static electricity to enter the source driver 1 through conductive paths such as the digital ground signal DVSS ground wire, the analog ground signal VSS_OSC ground wire, and the binding pad 33, resulting in static electricity attacking the source driver, which in turn causes irreversible problems such as screen flickering and abnormal display on the display.

[0043] For example, in the discharge path L2, due to the resistances between the ground plates GND, the first voltage signal (for example, the digital ground DVSS signal) and the second voltage signal (for example, the analog ground VSS OSC signal) will produce different voltage drops during transmission, thereby causing a voltage difference between the first voltage signal and the second voltage signal, and the ground signals of the digital circuit 11 and the analog circuit 12 are disturbed, which will cause the signal judgment reference to be inconsistent during system operation, and easily affect the digital logic operation and cause the problem of false touch operation.

[0044] To solve the above problems, the protection circuit 13 in the embodiment of the present application can control the voltage difference to be less than the threshold voltage in the case that the voltage difference between the first voltage signal and the second voltage signal is generated. That is, the protection circuit 13 is used to control the voltage difference within the range below the threshold voltage, in which case, the voltage difference between the digital ground signal and the analog ground signal will not affect the digital logic operation, ensuring the accuracy of the signal logic of the source driver 1, thereby improving the anti-static capability of the source driver 1.

[0045] In the source driver 1, there are more than one connection nodes between the digital ground and the analog ground, and the protection circuit 13 is a basic protection unit. Each additional protection circuit 13 in the system can cut off a possible conduction path for static electricity discharge. The scheme of arranging the protection circuit 13 inside the source driver 1 in the embodiment of the present application can be referred to as an internal scheme.

[0046] For example, in the case that the source driver 1 has high cost and high performance requirements, the internal scheme can be used to enhance the stability of the system in the static environment.

[0047] In some embodiments, as shown in Figure 1 The protection circuit 13 includes a buffer sub-circuit 131 and a switch sub-circuit 132. The buffer sub-circuit 131 is electrically connected with the digital circuit 11 and the analog circuit 12, and the switch sub-circuit 132 is electrically connected with the digital circuit 11 and the analog circuit 12. The switch sub-circuit 132 is configured to be turned on in the case that the voltage difference between the first voltage signal and the second voltage signal is greater than or equal to the threshold voltage, so that the buffer sub-circuit 131 controls the voltage difference to be less than the threshold voltage.

[0048] In the embodiment of the present application, if the first voltage signal D1 and the second voltage signal D2 produce a voltage difference due to the static attack, the switch sub-circuit 132 is turned on in the case that the voltage difference is greater than or equal to the threshold voltage, so that the buffer sub-circuit 131 regulates the voltage difference between the first voltage signal and the second voltage signal, and reduces the voltage difference to below the threshold voltage, thereby ensuring the accuracy of the signal logic of the source driver 1.

[0049] In some embodiments, as shown in Figure 1As shown, the protection circuit 13 includes a capacitor and two diodes. The first end of the capacitor is electrically connected with the digital circuit 11, and the second end of the capacitor is electrically connected with the analog circuit 12. Among the two diodes, the first pole of one diode is electrically connected with the first end of the capacitor, and the second pole is electrically connected with the second end of the capacitor; the first pole of the other diode is electrically connected with the second end of the capacitor, and the second pole is electrically connected with the first end of the capacitor.

[0050] In the embodiment of the present application, based on the connection mode of the two diodes, in the case that the electrostatic attack causes the first voltage signal D1 and the second voltage signal D2 to generate a voltage difference, the absolute value of the voltage difference is greater than the conduction voltage of the diode, and one of the two diodes must be in the conduction state to connect the two ends of the capacitor.

[0051] By charging or discharging the capacitor, the voltage at the two ends of the capacitor can be made to approach, that is, the voltage values of the first voltage signal D1 and the second voltage signal D2 can be made to approach, thereby reducing the voltage difference between the two, and ensuring the accuracy of the signal logic of the source driver 1.

[0052] For example, the threshold voltage mentioned in the foregoing can be the conduction voltage of the diode, and in the case that the voltage difference between the first voltage signal D1 and the second voltage signal D2 is greater than the conduction voltage of the diode, one of the two diodes is turned on to connect the two ends of the capacitor.

[0053] By making the voltage values of the first voltage signal D1 and the second voltage signal D2 approach through the capacitor, until the voltage difference between the two is less than the conduction voltage of the diode, both diodes are cut off, at this time, the voltage difference between the two is small, which will not affect the digital logic operation, thereby ensuring the accuracy of the signal logic of the source driver 1.

[0054] In some embodiments, as Figure 1 As shown, the digital circuit 11 includes a first sub-circuit 111 configured to output a digital control signal, and a first operational amplifier circuit 112 electrically connected with the first sub-circuit 111 and configured to receive the digital control signal and the first voltage signal D1 and output an enable control signal. The analog circuit 12 includes a second sub-circuit 121 electrically connected with the second operational amplifier circuit 122 and configured to output a clock control signal under the control of an analog control signal, and a second operational amplifier circuit 122 configured to receive the enable control signal and the second voltage signal D2 and output the analog control signal.

[0055] For example, the first sub-circuit 111 includes an automatic power adjustment circuit, which receives image information and instruction information, and generates a digital control signal according to the image information and the instruction information. The first operational amplifier circuit 112 generates an enable control signal according to the digital control signal, which is used to control the working state of the analog circuit 12. The second operational amplifier circuit 122 in the analog circuit 12 generates an analog control signal matched with the analog circuit according to the enable control signal. For example, the enable control signal has a low voltage level, and the second sub-circuit 121 needs a driving signal with a high voltage level. The second operational amplifier circuit 122 has a signal amplification function, which can generate an analog control signal with a voltage level matched with the second sub-circuit 121 according to the enable control signal. For example, the second sub-circuit 121 includes a crystal oscillator circuit, and the clock control signal output by the crystal oscillator circuit is a reference clock signal, which is used to synchronize the periodic signals of each component, and ensure the accuracy and stability of data transmission, processing and control.

[0056] In a second aspect, the present application also provides a display device, which comprises the source driver 1 and the display panel 21. Figure 3 As shown in the figure, Figure 3 A structural schematic diagram of a display device provided by an embodiment of the present application is shown in the figure.

[0057] The display device 2 includes the source driver 1 and the display panel 21 in any one of the embodiments of the first aspect, and the source driver 1 is electrically connected with the display panel 21.

[0058] For example, the display panel 21 includes a plurality of sub-pixels, and the plurality of sub-pixels include a plurality of rows and a plurality of columns. Each row of sub-pixels is electrically connected with a gate line, and each column of sub-pixels is electrically connected with a data line. The gate line is used to transmit a gate scanning signal to the sub-pixels, and the data line is used to transmit a data signal to the sub-pixels, so as to drive the sub-pixels to emit light.

[0059] The source driver 1 is electrically connected with the plurality of data lines on the display panel 21. The source driver 1 outputs the data signal and provides the data signal to the plurality of data lines on the display panel 21.

[0060] In the display device 2, when the system ground is attacked by static electricity, the protection circuit 13 in the source driver 1 can control the voltage difference to be less than the threshold voltage in the case that the first voltage signal and the second voltage signal generate a voltage difference. That is, the protection circuit 13 is used to control the voltage difference to be within a range below the threshold voltage. In this case, the voltage difference between the digital ground signal and the analog ground signal does not affect the digital logic operation, which ensures the accuracy of the signal logic of the source driver 1, thereby improving the anti-static capability of the source driver 1, and further avoiding the display device 2 from generating a flashing screen, abnormal display and other non-recoverable problems.

[0061] In a third aspect, the present application also provides a flexible circuit board, which comprises the source driver 1 and the display panel 21. Figure 4As shown, Figure 4 A schematic structural diagram of a flexible circuit board provided in an embodiment of the present application.

[0062] The flexible circuit board 3 includes a first power line 31, a second power line 32, and a protection circuit 13. The first power line 31 is used to transmit a first voltage signal D1, and the second power line 32 is used to transmit a second voltage signal D2. The protection circuit 13 is electrically connected to the first power line 31 and the second power line 32. The protection circuit 13 is configured to control the voltage difference between the first voltage signal D1 and the second voltage signal D2 to be less than a threshold voltage when a voltage difference occurs.

[0063] For example, Figure 2 As shown, the first power line 31 is used to transmit a first voltage signal D1 (for example, a digital ground DVSS signal) to the digital circuit 11 in the source driver 1, and the second power line 32 is used to transmit a second voltage signal D2 (for example, an analog ground VSS_OSC signal) to the analog circuit 12 in the source driver 1.

[0064] Taking the leakage path L2 as an example, when static electricity strikes the ground, due to the different resistances between the grounding plates, the first voltage signal on the first power line 31 (for example, the digital ground DVSS signal) and the second voltage signal on the second power line 32 (for example, the digital ground DVSS signal) will produce different voltage drops during the transmission process, thereby causing a voltage difference between the first voltage signal and the second voltage signal, causing the ground signals of the digital circuit 11 and the analog circuit 12 in the source driver 1 to be disordered. This will cause inconsistent signal judgment benchmarks during system operation, which can easily affect digital logic operations and cause false touch operations.

[0065] To address the above issues, the protection circuit 13 in the embodiment of the present application can control the voltage difference between the first voltage signal and the second voltage signal to be less than the threshold voltage. That is, the protection circuit 13 is used to control the voltage difference to be below the threshold voltage. In this case, the voltage difference between the digital ground signal and the analog ground signal does not affect digital logic operations, thereby ensuring the accuracy of the signal logic of the source driver 1 and improving the anti-static capability of the system.

[0066] Compared to the previously described internal solution, the solution in which the protection circuit 13 is disposed within the flexible circuit board 3 in the present embodiment can be referred to as an external solution. For example, when the source driver 1 is relatively low-cost and has relatively low performance requirements, this external solution can be adopted to enhance the stability of the system in an electrostatic environment.

[0067] In some embodiments, as Figure 4As shown, the protection circuit 13 includes a buffer subcircuit 131 and a switch subcircuit 132. The buffer subcircuit 131 is electrically connected to the first power line 31 and the second power line 32, and the switch subcircuit 132 is electrically connected to the first power line 31 and the second power line 32. The switch subcircuit 132 is configured to be turned on when the voltage difference between the first voltage signal and the second voltage signal is greater than or equal to a threshold voltage, so that the buffer subcircuit 131 controls the voltage difference to be less than the threshold voltage.

[0068] In the embodiment of the present application, if an electrostatic attack causes a voltage difference to occur between the first voltage signal D1 on the first power line 31 and the second voltage signal D2 on the second power line 32, then when the voltage difference is greater than or equal to the threshold voltage, the switch sub-circuit 132 is turned on, so that the buffer sub-circuit 131 regulates the voltage difference between the first voltage signal and the second voltage signal, reducing the voltage difference to below the threshold voltage, thereby ensuring the accuracy of the signal logic.

[0069] In some embodiments, as Figure 4 As shown, the protection circuit 13 includes a capacitor and two diodes. The first end of the capacitor is electrically connected to the first power line 31, and the second end of the capacitor is electrically connected to the second power line 32. Of the two diodes, the first electrode of one diode is electrically connected to the first end of the capacitor, and the second electrode is electrically connected to the second end of the capacitor. The first electrode of the other diode is electrically connected to the second end of the capacitor, and the second electrode is electrically connected to the first end of the capacitor.

[0070] In an embodiment of the present application, based on the connection method of the two diodes, when an electrostatic attack causes a voltage difference between the first voltage signal D1 and the second voltage signal D2, the absolute value of the voltage difference is greater than the conduction voltage of the diode, and one of the two diodes must be in the conduction state to connect the two ends of the capacitor.

[0071] By charging or discharging the capacitor, the voltages at both ends of the capacitor can be made close, that is, the voltage values ​​of the first voltage signal D1 and the second voltage signal D2 can be made close, thereby reducing the voltage difference between the two and ensuring the accuracy of the signal logic.

[0072] Exemplarily, the threshold voltage mentioned above may be the conduction voltage of the diode. When the voltage difference between the first voltage signal D1 and the second voltage signal D2 is greater than the conduction voltage of the diode, one of the two diodes is turned on to connect the two ends of the capacitor.

[0073] The capacitor is used to make the voltage values ​​of the first voltage signal D1 and the second voltage signal D2 approach each other until the voltage difference between the two is less than the conduction voltage of the diode. Both diodes are cut off. At this time, the voltage difference between the two is small and will not affect the digital logic operation, thereby ensuring the accuracy of the signal logic of the source driver 1.

[0074] In a fourth aspect, the present application also provides a display device, such as Figure 5 As shown in the figure, Figure 5 Another structural schematic diagram of a display device provided by the embodiments of the present application is shown in the figure.

[0075] The display device 4 comprises the flexible circuit board 3 and the display panel 21 in any of the embodiments of the third aspect.

[0076] Exemplarily, the display panel 21 comprises a plurality of sub-pixels, the plurality of sub-pixels comprises a plurality of rows and a plurality of columns, each row of sub-pixels is electrically connected to a gate line, and each column of sub-pixels is electrically connected to a data line. A gate scanning signal is transmitted to the sub-pixels through the gate line, and a data signal is transmitted to the sub-pixels through the data line, so as to drive the sub-pixels to emit light.

[0077] The source electrode driver 1 is bound on the flexible circuit board 3, and the flexible circuit board 3 functions as signal transmission, for transmitting the data signal output by the source electrode driver 1 to the plurality of data lines of the display panel 21.

[0078] In the display device 4, when the system ground is attacked by static electricity, the protection circuit 13 on the flexible circuit board 3 can control the voltage difference to be less than the threshold voltage in the case that the first voltage signal and the second voltage signal generate a voltage difference. That is, the protection circuit 13 is used to control the voltage difference to be within a range below the threshold voltage, in which case the voltage difference between the digital ground signal and the analog ground signal does not affect the digital logic operation, ensuring the accuracy of the signal logic of the system, thereby improving the anti-static capability of the system, and further avoiding the display device 4 from generating problems such as flashing screen, abnormal display, and the like which cannot be recovered.

[0079] The display device described above can be any device that displays images whether in motion (e.g., video) or fixed (e.g., still images), and whether textual or pictorial. More specifically, it is contemplated that the embodiments can be implemented in or in association with a variety of electronic devices such as, but not limited to, mobile telephones, wireless devices, personal data assistants (PDAs), hand-held or portable computers, GPS receivers / navigators, cameras, MP4 players, camcorders, game consoles, wrist watches, clocks, calculators, television monitors, flat panel displays, computer monitors, auto displays (e.g., odometer display, etc.), cockpit controls and / or displays, camera view displays (e.g., display of a rear view camera in a vehicle), electronic photographs, electronic billboards or signs, projections, architectural structures, packaging, and aesthetic structures (e.g., display of images on a piece of jewelry) and the like.

[0080] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can think of the changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A source driver, characterized in that: include: a digital circuit configured to receive a first voltage signal and output an enable control signal; an analog circuit electrically connected to the digital circuit; The analog circuit is configured to receive the enable control signal and the second voltage signal, and output a clock control signal; A protection circuit is electrically connected to the digital circuit and the analog circuit; the protection circuit is configured to control a voltage difference between the first voltage signal and the second voltage signal to be less than a threshold voltage when the voltage difference is generated.

2. The source driver according to claim 1, wherein: The protection circuit includes a buffer subcircuit and a switch subcircuit; The buffer subcircuit is electrically connected to the digital circuit and the analog circuit, and the switch subcircuit is electrically connected to the digital circuit and the analog circuit; The switch sub-circuit is configured to be turned on when the voltage difference is greater than or equal to the threshold voltage, so that the buffer sub-circuit controls the voltage difference to be less than the threshold voltage.

3. The source driver according to claim 1, wherein: The protection circuit includes a capacitor and two diodes; The first end of the capacitor is electrically connected to the digital circuit, and the second end of the capacitor is electrically connected to the analog circuit; the first pole of one of the two diodes is electrically connected to the first end of the capacitor, and the second pole is electrically connected to the second end of the capacitor; the first pole of the other diode is electrically connected to the second end of the capacitor, and the second pole is electrically connected to the first end of the capacitor.

4. The source driver according to claim 3, wherein: The threshold voltage is the conduction voltage of the diode.

5. The source driver according to claim 1, wherein: The digital circuit includes a first sub-circuit and a first operational amplifier circuit, wherein the first sub-circuit is configured to output a digital control signal; the first operational amplifier circuit is electrically connected to the first sub-circuit, and the first operational amplifier circuit is configured to receive the digital control signal and the first voltage signal and output the enable control signal; The analog circuit includes a second sub-circuit and a second operational amplifier circuit, the second operational amplifier circuit is configured to receive the enable control signal and the second voltage signal and output an analog control signal; the second sub-circuit is electrically connected to the second operational amplifier circuit, and the second sub-circuit is configured to output the clock control signal under the control of the analog control signal.

6. A display device, characterized in that: include: The source driver according to any one of claims 1 to 5; The source driver is electrically connected to the display panel.

7. A flexible circuit board, characterized in that: include: A first power line, used for transmitting a first voltage signal; a second power line, for transmitting a second voltage signal; A protection circuit is electrically connected to the first power line and the second power line; the protection circuit is configured to control a voltage difference between the first voltage signal and the second voltage signal to be less than a threshold voltage when the voltage difference is generated.

8. The flexible circuit board according to claim 7, characterized in that: The protection circuit includes a buffer subcircuit and a switch subcircuit; The buffer sub-circuit is electrically connected to the first power line and the second power line, and the switch sub-circuit is electrically connected to the first power line and the second power line; The switch sub-circuit is configured to be turned on when the voltage difference is greater than or equal to the threshold voltage, so that the buffer sub-circuit controls the voltage difference to be less than the threshold voltage.

9. The flexible circuit board according to claim 7, characterized in that: The protection circuit includes a capacitor and two diodes; The first end of the capacitor is electrically connected to the first power line, and the second end of the capacitor is electrically connected to the second power line; the first pole of one of the two diodes is electrically connected to the first end of the capacitor, and the second pole is electrically connected to the second end of the capacitor; the first pole of the other diode is electrically connected to the second end of the capacitor, and the second pole is electrically connected to the first end of the capacitor.

10. The flexible circuit board according to claim 9, characterized in that: The threshold voltage is the conduction voltage of the diode.

11. A display device, characterized in that: include: The flexible circuit board according to any one of claims 7 to 10; The flexible circuit board is electrically connected to the display panel.

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