Source driver, display device, and flexible wiring board

Abstract

The application 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 problems such as electrostatic discharge flash screen. The source driver comprises 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 with 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 with 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. Based on this, when an electrostatic attack signal occurs, the voltage difference between the digital ground signal and the analog ground signal does not affect the digital logic operation, the accuracy of the source driver signal logic is ensured, and the anti-static ability of the source driver is improved.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to a source driver, a display device, and a flexible circuit board. Background Technology

[0002] With the development of technology, wafer manufacturing processes are gradually shrinking. Taking the display technology field as an example, the current mainstream driver process for Active Matrix Organic Light Emitting Diode (AMOLED) is 28 / 40nm. However, as the market's requirements for driver performance, power consumption, and size gradually increase, the development of 22 / 16nm process has also been put on the agenda.

[0003] However, the smaller the manufacturing process, the weaker the electrostatic protection capability inside the driver, making it prone to problems such as electrostatic discharge and screen flickering. Summary of the Invention

[0004] This application discloses a source driver, a display device, a flexible circuit board, and a display device, which aim to improve the anti-static capability of the device.

[0005] To achieve the above objectives, embodiments of this 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 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 both the digital and analog circuits and is configured to control the voltage difference between the first and second voltage signals to be less than a threshold voltage when a voltage difference exists between them.

[0007] In some embodiments, the protection circuit includes a buffer sub-circuit and a switching sub-circuit. The buffer sub-circuit is electrically connected to both digital and analog circuits, and the switching sub-circuit is also electrically connected to both. The switching sub-circuit is configured to turn on when the voltage difference is greater than or equal to a threshold voltage, thereby causing the buffer sub-circuit to control the voltage difference to be less than the threshold voltage.

[0008] In some embodiments, the protection circuit includes a capacitor and two diodes. A first terminal of the capacitor is electrically connected to a digital circuit, and a second terminal of the capacitor is electrically connected to an analog circuit. Of the two diodes, the first terminal of one diode is electrically connected to the first terminal of the capacitor, and the second terminal of the other diode is electrically connected to both terminals of the capacitor.

[0009] In some embodiments, the threshold voltage is the diode's forward voltage.

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

[0011] In this embodiment, the digital circuit is configured to receive a first voltage signal, and the analog circuit is configured to receive a second voltage signal. When static electricity strikes the ground, due to the presence of resistances of varying magnitudes in the discharge path, the first voltage signal (e.g., the digital ground DVSS signal) and the second voltage signal (e.g., the analog ground VSS_OSC signal) will generate different voltage drops during transmission, resulting in a voltage difference between the first and second voltage signals. This will cause the ground signals of the digital and analog circuits to become disordered, leading to inconsistent signal judgment benchmarks during system operation, which can easily affect digital logic operations and cause erroneous operation problems.

[0012] The protection circuit can control the voltage difference between the first and second voltage signals to be less than a threshold voltage. In other words, the protection circuit controls the voltage difference to be below the threshold voltage. Under these conditions, 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 source driver signal logic and thus improving the source driver's anti-static capability.

[0013] Secondly, this application also provides a display device, including a source driver and a display panel as described in any of the embodiments of the first aspect above, wherein the source driver is electrically connected to the display panel.

[0014] This display device has the same technical effect as the aforementioned source driver, which will not be described in detail here.

[0015] Thirdly, this application also provides a flexible circuit board, including a first power line, a second power line, and a protection circuit. The first power line is used to transmit a first voltage signal, the second power line is used to transmit a second voltage signal, and the protection circuit is electrically connected to the first and second power lines. The protection circuit is configured to control the voltage difference to be less than a threshold voltage when a voltage difference is generated between the first and second voltage signals.

[0016] In some embodiments, the protection circuit includes a buffer sub-circuit and a switching sub-circuit. The buffer sub-circuit is electrically connected to a first power line and a second power line, and the switching sub-circuit is electrically connected to both the first and second power lines. The switching sub-circuit is configured to turn on when the voltage difference is greater than or equal to a threshold voltage, thereby causing the buffer sub-circuit to control the voltage difference to be less than the threshold voltage.

[0017] In some embodiments, the protection circuit includes a capacitor and two diodes. A first terminal of the capacitor is electrically connected to a first power line, and a second terminal of the capacitor is electrically connected to a second power line. Of the two diodes, the first terminal of one diode is electrically connected to the first terminal of the capacitor, and the second terminal of the other diode is electrically connected to both the first and second terminals of the capacitor.

[0018] In some embodiments, the threshold voltage is the diode's forward voltage.

[0019] In this embodiment, the first power line is used to transmit a first voltage signal, and the second power line is used to transmit a second voltage signal. When static electricity strikes the ground, due to the varying resistances along the discharge path, the first voltage signal (e.g., the digital ground DVSS signal) on the first power line and the second voltage signal (e.g., the digital ground DVSS signal) on the second power line will generate different voltage drops during transmission. This will cause a voltage difference between the first and second voltage signals, resulting in disordered ground signals in the digital and analog circuits of the source driver. This will cause inconsistent signal judgment benchmarks during system operation, which may easily affect digital logic operations and lead to accidental operation.

[0020] The protection circuit can control the voltage difference between the first and second voltage signals to be less than a threshold voltage. In other words, the protection circuit controls the voltage difference to be below the threshold voltage. Under these conditions, the voltage difference between the digital ground signal and the analog ground signal will not affect digital logic operations, ensuring the accuracy of the system's signal logic and thus improving the system's anti-static capability.

[0021] Fourthly, this application also provides a display device, including a flexible circuit board and a display panel as described in any of the embodiments of the third aspect above, wherein the flexible circuit board and the display panel are electrically connected.

[0022] This display device has the same technical effects as the aforementioned flexible circuit board, which will not be described in detail here. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in some embodiments of this application will be briefly described below. Obviously, the drawings described below are only drawings of some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not actual dimensions of the products or actual processes of the methods involved in the embodiments of this application.

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

[0025] Figure 2 This application provides a schematic diagram of the discharge path when electrostatic discharge strikes the ground.

[0026] Figure 3 This is a schematic diagram of the structure of a display device provided in an embodiment of this application;

[0027] Figure 4 This is a schematic diagram of the structure of a flexible circuit board provided in an embodiment of this application;

[0028] Figure 5 This is a schematic diagram of another display device provided in an embodiment of this application. Detailed Implementation

[0029] The technical solutions in some embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application are within the scope of protection of this application.

[0030] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open and encompassing, that is, "including, but not limited to".

[0031] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this application, unless otherwise stated, "a plurality of" means two or more.

[0032] In describing some embodiments, the term "connection" and its derivative expressions may be used. The term "connection" should be interpreted broadly; for example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium. For example, in describing some embodiments, the term "connection" may be used to indicate that two or more components have direct physical or electrical contact with each other.

[0033] In addition, the use of “based on” implies openness and inclusivity, because processes, steps, calculations or other actions “based on” one or more of the stated conditions or values ​​may in practice be based on additional conditions or values ​​beyond those stated.

[0034] It should be understood that when a layer or element is referred to as being on another layer or substrate, it can mean that the layer or element is directly on the other layer or substrate, or that there is an intermediate layer between the layer or element and the other layer or substrate.

[0035] This document describes exemplary embodiments with reference to cross-sectional views, which are intended as idealized exemplary drawings. In the drawings, the thickness of the layers and the area of ​​the regions are enlarged for clarity. Therefore, variations in shape relative to the drawings are contemplated due to, for example, manufacturing techniques and / or tolerances. Thus, exemplary embodiments should not be construed as limited to the shapes of the regions shown herein, but rather include shape deviations caused, for example, by manufacturing processes. For example, etched areas shown as rectangular would typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shapes of the areas of the device, nor are they intended to limit the scope of the exemplary embodiments.

[0036] As technology advances and wafer manufacturing processes shrink, the smaller the process, the weaker the electrostatic discharge (ESD) protection capability of the driver. This makes the design of the driver to withstand ESD surges more difficult, requiring more ESD protection circuitry. Currently, driver ESD protection designs are primarily based on protection against ESD surges on the high or low level signals themselves, neglecting the ground potential disturbances caused by ESD attacks on ground signals. Ground potential disturbances can cause system signal logic errors. Related technologies mitigate this problem by continuously increasing the area of ​​the ground plane, but lack dedicated protection circuitry to prevent ESD-induced screen flickering and other issues caused by ESD attacks on ground signals.

[0037] To address the aforementioned problems, this application provides a source driver, such as... Figure 1 As shown, Figure 1 This is a schematic diagram of the circuit structure of a source driver provided in an embodiment of this 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 is 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 both the digital circuit 11 and the analog circuit 12 and 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 exists between them.

[0039] For example, the first voltage signal D1 received by the digital circuit 11 is a digital ground signal, such as the DVSS signal, and its output enable control signal 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 for the system, such as OSC_CLK.

[0040] When electrostatic discharge strikes the system ground, it causes disturbance of the ground signal inside the source driver 1, resulting in a voltage difference between the first voltage signal D1 and the second voltage signal D2. The mechanism is described below.

[0041] like Figure 2 As shown, Figure 2 This is a schematic diagram of the discharge path when electrostatic discharge strikes the ground, provided as an embodiment of this application.

[0042] When electrostatic discharge (ESD) strikes the system ground, it is typically input directly through the copper drain area 301 on the flexible circuit board 3. Typically, such as... Figure 2 As shown in the discharge path L1, most of the energy can be discharged directly through connector 14 via the ground plane GND of the flexible circuit board 3. However, as... Figure 2 As shown in the discharge path L2, due to the segmented design of the ground plane GND of the flexible circuit board 3, there are different resistances between the various ground plane GNDs connected together through vias and grounding wires. This can cause static electricity to enter the source driver 1 through conductive paths such as the digital ground signal DVSS grounding wire, the analog ground signal VSS_OSC grounding wire, and the bonding pad 33, resulting in an electrostatic discharge attack on the source driver, which in turn causes irreversible problems such as screen flickering and abnormal display.

[0043] Taking the leakage path L2 as an example, since there are different resistances between each ground plane GND, the first voltage signal (e.g., digital ground DVSS signal) and the second voltage signal (e.g., analog ground VSS_OSC signal) will generate different voltage drops during transmission, which will cause a voltage difference between the first voltage signal and the second voltage signal, causing the ground signals of digital circuit 11 and analog circuit 12 to be disordered. This will cause the signal judgment benchmark to be inconsistent during the operation of the system, which can easily affect digital logic operations and lead to the problem of accidental operation.

[0044] To address the aforementioned issues, the protection circuit 13 in this embodiment can control the voltage difference between the first voltage signal and the second voltage signal to be less than a threshold voltage when a voltage difference is generated. That is, the protection circuit 13 is used to control the voltage difference within a range below the threshold voltage. Under these conditions, 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] Within the source driver 1, there is more than one connection node between the digital ground and the analog ground. The protection circuit 13 serves as a basic protection unit. Each additional protection circuit 13 in the system can cut off a possible conduction path for electrostatic discharge. The scheme in this application embodiment that places the protection circuit 13 inside the source driver 1 can be referred to as an internal scheme.

[0046] For example, when the source driver 1 is expensive and has high performance requirements, this built-in solution can be used to enhance the stability of the system in an electrostatic environment.

[0047] In some embodiments, such as Figure 1 As shown, the protection circuit 13 includes a buffer sub-circuit 131 and a switch sub-circuit 132. The buffer sub-circuit 131 is electrically connected to the digital circuit 11 and the analog circuit 12, and the switch sub-circuit 132 is electrically connected to both the digital circuit 11 and the analog circuit 12. The switch sub-circuit 132 is configured to turn on when the voltage difference between the first voltage signal and the second voltage signal is greater than or equal to a threshold voltage, thereby causing the buffer sub-circuit 131 to control the voltage difference to be less than the threshold voltage.

[0048] In this embodiment, if an electrostatic discharge causes a voltage difference between the first voltage signal D1 and the second voltage signal D2, the switching sub-circuit 132 is turned on when the voltage difference is greater than or equal to a threshold voltage, so that the buffer sub-circuit 131 can regulate 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 of the source driver 1.

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

[0050] In this embodiment of the 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. Therefore, one of the two diodes must be in the conducting state to connect the two ends of the capacitor.

[0051] By charging or discharging the capacitor, the voltage across the capacitor can be brought closer together, which in turn can bring the voltage values ​​of the first voltage signal D1 and the second voltage signal D2 closer together, thereby reducing the voltage difference between them and ensuring the accuracy of the signal logic of the source driver 1.

[0052] For example, the threshold voltage mentioned above can be the diode's forward voltage. When the voltage difference between the first voltage signal D1 and the second voltage signal D2 is greater than the diode's forward voltage, one of the two diodes turns on to connect the two ends of the capacitor.

[0053] The voltage values ​​of the first voltage signal D1 and the second voltage signal D2 are brought closer together by a capacitor until the voltage difference between them is less than the forward voltage of the diodes. Both diodes are then turned off. At this point, the voltage difference between them is small and will not affect the digital logic operation, thus ensuring the accuracy of the signal logic of the source driver 1.

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

[0055] For example, the first sub-circuit 111 includes an automatic power adjustment circuit for receiving image information and instruction information, and generating digital control signals accordingly. The first operational amplifier circuit 112 generates an enable control signal based on this digital control signal to control the operating state of the analog circuit 12. The second operational amplifier circuit 122 in the analog circuit 12 generates an analog control signal that matches the analog circuit based on this enable control signal. For example, if the enable control signal voltage level is low, and the second sub-circuit 121, as part of the analog circuit 12, requires a higher voltage level for its drive signal, the signal amplification function of the second operational amplifier circuit 122 can generate an analog control signal that matches the voltage level of the second sub-circuit 121 based on the enable control signal. For example, the second sub-circuit 121 includes a crystal oscillator circuit, whose output clock control signal is a reference clock signal used to synchronize the periodic signals of the various components, ensuring the accuracy and stability of data transmission, processing, and control.

[0056] Secondly, this application also provides a display device, such as... Figure 3 As shown, Figure 3 This is a schematic diagram of the structure of a display device provided in an embodiment of this application.

[0057] The display device 2 includes a source driver 1 and a display panel 21 as described in any of the embodiments of the first aspect above, wherein the source driver 1 is electrically connected to the display panel 21.

[0058] For example, the display panel 21 includes a plurality of sub-pixels, which include multiple rows and multiple 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 scan 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 to drive the sub-pixels to emit light.

[0059] The source driver 1 is electrically connected to multiple data lines on the display panel 21. The source driver 1 outputs data signals and provides them to the multiple data lines on the display panel 21.

[0060] In this display device 2, when electrostatic discharge (ESD) strikes the system ground, the protection circuit 13 within the source driver 1 can control the voltage difference between the first voltage signal and the second voltage signal to be less than a threshold voltage. That is, the protection circuit 13 is used to control the voltage difference within a range below the threshold voltage. Under these conditions, the voltage difference between the digital ground signal and the analog ground signal will not affect digital logic operations, ensuring the accuracy of the signal logic of the source driver 1. This improves the anti-ESD capability of the source driver 1 and thus avoids irreversible problems such as screen flickering and abnormal display in the display device 2.

[0061] Thirdly, this application also provides a flexible circuit board, such as Figure 4As shown, Figure 4 This is a schematic diagram of the structure of a flexible circuit board provided in an embodiment of this 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, the second power line 32 is used to transmit a second voltage signal D2, and 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 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.

[0063] For example, such as Figure 2 As shown, the first power line 31 is used to transmit a first voltage signal D1 (e.g., 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 (e.g., analog ground VSS OSC signal) to the analog circuit 12 in the source driver 1.

[0064] Taking the discharge path L2 as an example, when electrostatic discharge strikes the ground, due to the varying resistance between the grounding plates, the first voltage signal (e.g., digital ground DVSS signal) on the first power line 31 and the second voltage signal (e.g., digital ground DVSS signal) on the second power line 32 will generate different voltage drops during transmission. This will cause a voltage difference between the first voltage signal and the second voltage signal, resulting in disorder of the ground signals of the digital circuit 11 and analog circuit 12 in the source driver 1. This will cause inconsistent signal judgment benchmarks during system operation, which may easily affect digital logic operations and lead to erroneous operation.

[0065] To address the aforementioned issues, the protection circuit 13 in this embodiment can control the voltage difference between the first voltage signal and the second voltage signal to be less than a threshold voltage when a voltage difference is generated. That is, the protection circuit 13 is used to control the voltage difference within a range below the threshold voltage. Under these conditions, 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 signal logic of the source driver 1 and improving the system's anti-static capability.

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

[0067] In some embodiments, such as Figure 4As shown, the protection circuit 13 includes a buffer sub-circuit 131 and a switch sub-circuit 132. The buffer sub-circuit 131 is electrically connected to the first power line 31 and the second power line 32, and the switch sub-circuit 132 is electrically connected to both the first power line 31 and the second power line 32. The switch sub-circuit 132 is configured to turn on when the voltage difference between the first voltage signal and the second voltage signal is greater than or equal to a threshold voltage, thereby causing the buffer sub-circuit 131 to control the voltage difference to be less than the threshold voltage.

[0068] In this embodiment of the application, if an electrostatic discharge causes a voltage difference 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 if 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 can regulate the voltage difference between the first voltage signal and the second voltage signal, reduce the voltage difference to below the threshold voltage, thereby ensuring the accuracy of the signal logic.

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

[0070] In this embodiment of the 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. Therefore, one of the two diodes must be in the conducting state to connect the two ends of the capacitor.

[0071] By charging or discharging the capacitor, the voltage across its terminals can be brought closer together. This, in turn, brings the voltage values ​​of the first voltage signal D1 and the second voltage signal D2 closer together, thereby reducing the voltage difference and ensuring the accuracy of the signal logic.

[0072] For example, the threshold voltage mentioned above can be the diode's forward voltage. When the voltage difference between the first voltage signal D1 and the second voltage signal D2 is greater than the diode's forward voltage, one of the two diodes turns on to connect the two ends of the capacitor.

[0073] The voltage values ​​of the first voltage signal D1 and the second voltage signal D2 are brought closer together by a capacitor until the voltage difference between them is less than the forward voltage of the diodes. Both diodes are then turned off. At this point, the voltage difference between them is small and will not affect the digital logic operation, thus ensuring the accuracy of the signal logic of the source driver 1.

[0074] Fourthly, this application also provides a display device, such as... Figure 5 As shown, Figure 5 This is a schematic diagram of another display device provided in an embodiment of this application.

[0075] The display device 4 includes a flexible circuit board 3 and a display panel 21 as described in any of the embodiments of the third aspect above, wherein the flexible circuit board 3 is electrically connected to the display panel 21.

[0076] For example, the display panel 21 includes a plurality of sub-pixels, which include multiple rows and multiple 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 scan 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 to drive the sub-pixels to emit light.

[0077] The flexible circuit board 3 is bound to the source driver 1. The flexible circuit board 3 plays the role of signal transmission, which is used to transmit the data signal output by the source driver 1 to multiple data lines of the display panel 21.

[0078] In this display device 4, when electrostatic discharge (ESD) strikes the system ground, the protection circuit 13 on the flexible circuit board 3 can control the voltage difference between the first voltage signal and the second voltage signal to be less than a threshold voltage. That is, the protection circuit 13 is used to control the voltage difference within a range below the threshold voltage. Under these conditions, the voltage difference between the digital ground signal and the analog ground signal will not affect digital logic operations, ensuring the accuracy of the system's signal logic, thereby improving the system's anti-static capability and preventing irreversible problems such as screen flickering and abnormal display from occurring in the display device 4.

[0079] The aforementioned display device can be any device that displays images, whether moving (e.g., video) or fixed (e.g., still images), and whether it contains text or images. More specifically, the embodiments described are contemplated to be implemented in or associated with a variety of electronic devices, such as (but not limited to) mobile phones, wireless devices, personal data assistants (PDAs), handheld or portable computers, GPS receivers / navigators, cameras, MP4 video players, camcorders, game consoles, watches, clocks, calculators, television monitors, flat panel displays, computer monitors, automotive displays (e.g., odometer displays, etc.), navigators, cockpit controllers and / or displays, displays of camera views (e.g., displays of rearview cameras in vehicles), electronic photographs, electronic billboards or signs, projectors, architectural structures, packaging and aesthetic structures (e.g., displays of images of a piece of jewelry), etc.

[0080] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

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

2. The source driver according to claim 1, characterized in that, 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 switching sub-circuit is configured to turn 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, characterized in that, The protection circuit includes a capacitor and two diodes; The first terminal of the capacitor is electrically connected to the digital circuit, and the second terminal of the capacitor is electrically connected to the analog circuit; of the two diodes, the first terminal of one diode is electrically connected to the first terminal of the capacitor, and the second terminal is electrically connected to the second terminal of the capacitor; the first terminal of the other diode is electrically connected to the second terminal of the capacitor, and the second terminal is electrically connected to the first terminal of the capacitor.

4. The source driver according to claim 3, characterized in that, The threshold voltage is the forward voltage of the diode.

5. The source driver according to claim 1, characterized in that, The digital circuit includes a first sub-circuit and a first operational amplifier circuit. 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 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: Source driver as described in 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: The first power line is used to transmit the first voltage signal; The second power supply line is used to transmit the 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 the voltage difference to be less than a threshold voltage when a voltage difference is generated between the first voltage signal and the second voltage signal.

8. The flexible circuit board according to claim 7, characterized in that, 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 switching sub-circuit is configured to turn 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; 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.

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

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

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