Control circuit for time schedule controller, display panel and display device

Abstract

The utility model relates to the technical field of display, in particular to a control circuit for a time schedule controller, a display panel and a display device, and the control circuit is connected with an output port of the time schedule controller through a control end of a main switch tube to access a control voltage signal. The voltage control circuit is connected with a main switching tube, a first end of the main switching tube is connected with a power supply module to access a first voltage signal, an output voltage signal is provided through a second end of the main switching tube, then the voltage control circuit is turned off in a first level state of the control voltage signal, and the output voltage signal is stabilized at the first voltage signal; or in a second level state of the control voltage signal, the voltage control circuit is switched on, the output voltage signal is stabilized at a preset voltage signal, and the preset voltage signal changes along with the change of the first voltage signal. Therefore, the anti-interference capability of the display module can be improved while the quality of the input signal is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of display, in particular to a control circuit for a timing controller, a display panel and a display device. Background Art

[0002] For a display panel to display an image, an input signal needs to be provided by a front-end system, such as an RGB (Red, Green, Blue) signal, an LVDS (Low Voltage Differential Signaling) signal, an eDP (Embedded Display Port) signal, etc. These input signals include RGB grayscale data signals, control signals, clock signals, etc. Therefore, the quality of the input signal determines the quality of the display panel's image.

[0003] The input signal provided by the front-end system is affected by the following three factors: The first is affected by the quality of the signal itself during generation; the second is affected by the resistance and capacitance in the input signal transmission line; the third is affected by the external electromagnetic field. There are many factors affecting the quality of the input signal. Once the quality of the input signal deteriorates, it will directly cause problems such as color deviation and screen flickering of the image. Therefore, it is very important to improve the quality of the input signal of the display panel. Currently, due to the different core voltages of various types of TCON (Timing Controller), there are certain differences in the maximum swing (i.e., the signal Swing value) output by them. The maximum Swing value has a great impact on the anti-interference ability of the display module. Therefore, during the panel design stage, sometimes considering the requirement of design power consumption, a TCON with a low core voltage is selected, and the corresponding maximum Swing value will also be small. At this time, the anti-interference ability of the display module will also decrease accordingly.

[0004] The commonly used method in the industry to improve the quality of the input signal is: after the control chip TCON of the display panel receives the input signal transmitted by the front-end system, the signal Swing value is adjusted by adjusting the TCON register, so that the fluctuation of the signal is obvious, and thus it is easier to obtain an effective signal output. However, this technology is limited by the TCON core voltage. Even if the maximum Swing voltage is output, the anti-interference ability of the display module may not meet the customer's requirements. Moreover, after the swing of the signal is increased, since the signal is enhanced, the EMC (Electro Magnetic Compatibility) of the display panel will also increase accordingly. This will not only cause electromagnetic interference to surrounding electronic products, but also be more susceptible to interference from other electronic products.

[0005] Therefore, how to improve the anti-interference ability of the display module while improving the quality of the input signal is an urgent problem to be solved. Summary of the Utility Model

[0006] To solve the above technical problems, the present utility model provides a control circuit for a timing controller, a display panel, and a display device, which can improve the input signal quality and the anti-interference ability of the display module at the same time.

[0007] On the one hand, a control circuit for a timing controller provided by the present utility model includes:

[0008] A main switch transistor, the control terminal of the main switch transistor is connected to the output port of the timing controller to receive a control voltage signal, the first terminal of the main switch transistor is connected to a power supply module to receive a first voltage signal, and the second terminal of the main switch transistor serves as the output terminal of the control circuit to provide an output voltage signal;

[0009] A voltage control circuit, the input terminal of the voltage control circuit is connected to the control terminal of the main switch transistor, and the output terminal of the voltage control circuit is connected to the second terminal of the main switch transistor.

[0010] When the control voltage signal is in the first level state, the voltage control circuit is turned off, and the output voltage signal is stabilized at the first voltage signal;

[0011] Or when the control voltage signal is in the second level state, the voltage control circuit is turned on, and the output voltage signal is stabilized at a preset voltage signal, and the preset voltage signal changes following the change of the first voltage signal.

[0012] Preferably, when the control voltage signal is in the first level state, the main switch transistor is turned on;

[0013] When the control voltage signal is in the second level state, the main switch transistor is turned off.

[0014] Preferably, the first level state of the control voltage signal is a low level state, and the second level state of the control voltage signal is a high level state;

[0015] Or, the first level state of the control voltage signal is a high level state, and the second level state of the control voltage signal is a low level state.

[0016] Preferably, the voltage control circuit includes:

[0017] A first resistor, a first switch transistor, and a first constant voltage source. The first end of the first resistor is grounded, the second end of the first resistor is connected to the first end of the first switch transistor, the second end of the first switch transistor is connected to the first constant voltage source to ground, and the control terminal of the first switch transistor serves as the input terminal of the voltage control circuit and is connected to the control terminal of the main switch transistor;

[0018] A second constant voltage source and a second switching transistor. The first terminal of the second constant voltage source is grounded, the second terminal of the second constant voltage source is connected to the first terminal of the second switching transistor, the second terminal of the second switching transistor serves as the output terminal of the voltage control circuit and is connected to the second terminal of the main switching transistor, and the control terminal of the second switching transistor is connected to the intermediate node between the first switching transistor and the first constant voltage source.

[0019] Preferably, in the first level state of the control voltage signal, both the first switching transistor and the second switching transistor are turned off;

[0020] In the second level state of the control voltage signal, both the first switching transistor and the second switching transistor are turned on.

[0021] Preferably, the first constant voltage source is built in the power supply module to provide a second voltage signal;

[0022] The second constant voltage source is the output node of a low dropout linear regulator to provide the preset voltage signal.

[0023] Preferably, any one of the main switching transistor, the first switching transistor, and the second switching transistor is a metal oxide semiconductor field effect transistor.

[0024] Preferably, both the main switching transistor and the second switching transistor are P-channel metal oxide semiconductor field effect transistors, and the first switching transistor is an N-channel metal oxide semiconductor field effect transistor.

[0025] On the other hand, a display panel provided by the present invention includes:

[0026] A plurality of sub-pixels arranged in an array in the display area;

[0027] A timing controller, a source driver, and a gate driver. The timing controller performs conversion processing on display data, then inputs signals related to gate driving to the gate driver, and inputs signals related to source driving to the source driver;

[0028] The control circuit for the timing controller as described above.

[0029] On the other hand, a display device provided by the present invention further includes the display panel as described above.

[0030] The beneficial effects of the present utility model are as follows: The present utility model provides a control circuit, a display panel and a display device for a timing controller. The control circuit accesses a control voltage signal through the control terminal of the main switching tube connected to the output port of the timing controller, connects the first end of the main switching tube to a power supply module to access a first voltage signal, and provides an output voltage signal through the second end of the main switching tube. Then, in the first level state of the control voltage signal, the voltage control circuit is in an off state to maintain the output voltage signal stable at the first voltage signal; or in the second level state of the control voltage signal, the voltage control circuit is in a conducting state to clamp the output voltage signal stable at a preset voltage signal, and the preset voltage signal changes following the potential of the first voltage signal. Thus, within the rated voltage range of the TCON and on the premise of meeting the design power consumption, by boosting the TCON core voltage, the output Swing voltage is increased, so that while improving the quality of the input signal, the anti-interference ability of the display module can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Through the following description of the embodiments of the present utility model with reference to the accompanying drawings, the above and other objects, features and advantages of the present utility model will become more apparent.

[0032] Figure 1 Showing a schematic diagram of the principle of the PCB board and the display area in the prior art;

[0033] Figure 2 Showing a schematic diagram of the principle of TCON and S-COF driving in the prior art;

[0034] Figure 3 Showing a schematic structural diagram of the display panel provided by the embodiment of the present utility model;

[0035] Figure 4 Showing Figure 3 A schematic diagram of the principle of the control circuit for the timing controller shown;

[0036] Figure 5a And Figure 5b Showing the waveform schematic diagrams of the maximum Swing voltages output in the prior art and in this embodiment respectively. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] To facilitate the understanding of the present utility model, the present utility model will be described more comprehensively below with reference to the relevant accompanying drawings. The preferred embodiments of the present utility model are shown in the drawings. However, the present utility model can be implemented in different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure content of the present utility model more thorough and comprehensive.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this utility model belongs. The terms used in the description of this utility model herein are for the purpose of describing specific embodiments only and are not intended to limit this utility model.

[0039] TFT-LCD (Thin Film Transistor Liquid Crystal Display) is one of the main types of current flat panel displays and has become an important display platform in modern IT and video products. The main driving principle of TFT-LCD is that the system main board connects the R / G / B compressed signals, control signals, and power through wires to the connector on the PCB board. After the data is processed by the timing controller chip on the PCB board, it passes through the PCB board and is connected to the display area through S-COF (Source-Chip on Film) and G-COF (Gate-Chip on Film), so that the LCD can obtain the required power and signals, such as Figure 1 and Figure 2 shown. The maximum swing of the differential signal of the mini-LVDS signal for communication between the timing controller TCON and the S-COF relative to the reference voltage is related to EMI (ElectroMagnetic Interference). The larger the Swing value, the greater the energy value at this frequency point, and the worse the EMI result. And the smaller the Swing value, the better the EMI result, but it may cause the S-COF to be unable to correctly read the data, affecting the quality of the input signal.

[0040] Based on this, the embodiments of this utility model provide a control circuit, a display panel, and a display device for a timing controller, which can improve the anti-interference ability of the display module while improving the quality of the input signal.

[0041] Next, this utility model will be described in detail with reference to the accompanying drawings.

[0042] Figure 3 shows a schematic structural diagram of a display panel provided by an embodiment of this utility model, Figure 4 shows Figure 3 the schematic principle diagram of the control circuit for the timing controller shown, Figure 5a and Figure 5b respectively show the waveform schematic diagrams of the maximum Swing voltage output in the prior art and this embodiment.

[0043] Referring to Figure 3 , the embodiments of this utility model provide a display panel 10, which includes:

[0044] A plurality of sub-pixels (not shown, for reference Figure 1 and understanding with the existing panel structure) are arranged in an array in the display area;

[0045] A timing controller 200 and a driving circuit 400 (a source driver and a gate driver), wherein the timing controller 200 performs conversion processing on display data, and then inputs a signal related to gate driving to the gate driver, and inputs a signal related to source driving to the source driver;

[0046] A control circuit 100 for the timing controller 200 provided in this embodiment.

[0047] Reference Figure 4 , an embodiment of the present invention provides a control circuit 100 for a timing controller 200, which may include: a main switching transistor PM1 and a voltage control circuit 110.

[0048] Wherein, the control end of the main switching transistor PM1 is connected to the output port of the timing controller 200 (in this embodiment, it is the TCON GPIO port), and a control voltage signal Vb is accessed. The first end of the main switching transistor PM1 is connected to the power supply module 300, and a first voltage signal V1 is accessed. The second end of the main switching transistor PM1 serves as the output end A of the control circuit 100 to provide an output voltage signal Vout;

[0049] The input end B of the voltage control circuit 110 is connected to the control end of the main switching transistor PM1, and the output end of the voltage control circuit 110 is connected to the second end A of the main switching transistor PM1.

[0050] In the first level state of the control voltage signal Vb, the voltage control circuit 110 is in an off state to maintain the output voltage signal Vout stable at the first voltage signal V1;

[0051] Or in the second level state of the control voltage signal Vb, the voltage control circuit 110 is in a conducting state to clamp the output voltage signal Vout stable at a preset voltage signal V3, and the preset voltage signal V3 changes following the potential of the first voltage signal V1.

[0052] In some embodiments, in the first level state of the control voltage signal Vb, the main switching transistor PM1 is in a conducting state; in the second level state of the control voltage signal Vb, the main switching transistor PM1 is in an off state.

[0053] In some embodiments, the first level state of the control voltage signal Vb is a low level state, and the second level state of the control voltage signal Vb is a high level state;

[0054] Alternatively, the first level state of the control voltage signal Vb is a high level state, and the second level state of the control voltage signal Vb is a low level state. In this embodiment, it is preferably that the first level state of the control voltage signal Vb is a low level state, and the second level state of the control voltage signal Vb is a high level state.

[0055] In some embodiments, the voltage control circuit 110 may include: a first resistor R1, a first switching transistor NM1, a first constant voltage source, a second constant voltage source, and a second switching transistor PM2.

[0056] Wherein, a first end of the first resistor R1 is grounded, a second end of the first resistor R1 is connected to a first end of the first switching transistor NM1, a second end of the first switching transistor NM1 is connected from the first constant voltage source to ground, and a control end of the first switching transistor NM1 serves as an input terminal B of the voltage control circuit 110 and is connected to a control end of the main switching transistor PM1; a first end of the second constant voltage source is grounded, a second end of the second constant voltage source is connected to a first end of the second switching transistor PM2, a second end of the second switching transistor PM2 serves as an output terminal A of the voltage control circuit 110 and is connected to a second end of the main switching transistor PM1, and a control end of the second switching transistor PM2 is connected to an intermediate node C between the first switching transistor NM1 and the first constant voltage source.

[0057] In some embodiments, in the first level state of the control voltage signal Vb, both the first switching transistor NM1 and the second switching transistor PM2 are in an off state; in the second level state of the control voltage signal Vb, both the first switching transistor NM1 and the second switching transistor PM2 are in an on state.

[0058] In some embodiments, the first constant voltage source is built in the power supply module 300 to provide a second voltage signal V2; the second constant voltage source is an output node of a low dropout linear regulator (LDO) to provide the preset voltage signal V3.

[0059] In some embodiments, any one of the main switching transistor PM1, the first switching transistor NM1, and the second switching transistor PM2 is a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET, hereinafter simply referred to as MOS transistor).

[0060] In some embodiments, both the main switching transistor PM1 and the second switching transistor PM2 are P-channel MOS transistors, and the first switching transistor NM1 is an N-channel MOS transistor.

[0061] In Figure 4 in the control circuit 100, if the magnitude of the first voltage signal V1 is set to 0.9V, the magnitude of the second voltage signal V2 is set to 1.8V, and the magnitude of the preset voltage signal V3 is set to 0.95V (the foregoing numerical values are only randomly set parameters for convenient experimental verification and can be set according to requirements in specific operations. Here, it is only used as an example and is not limited), in the first state (i.e., the Normal state, which is also the state without external interference), the control voltage signal Vb output by the TCON GPIO port is in a low level state, and the main switch PM1 is normally conducting. Therefore, the output voltage signal Vout at point A is 0.9V. At this time, the second switch PM2 and the first switch NM1 are not conducting. Therefore, the voltage at point B is 0V, and the voltage at point C is 1.8V. In the second state (such as the 2gmode state where the module is interfered by a mobile phone in a call), the control voltage signal Vb output by the TCON GPIO port is a high level of 3.3V, which causes the main switch PM1 to turn off. Subsequently, the first switch NM1 and the second switch PM2 conduct. Therefore, the voltage at point B is 3.3V, the voltage at point C is 0V, and the voltage at point A is 0.945V.

[0062] Therefore, through the control circuit 100 built between the power supply module 300 and the timing controller 200 in the above embodiments, each time the device is powered on, if the S-COF cannot correctly read the data, the control voltage signal Vb output by the TCON GPIO port is a high level. Through the control circuit 100, within the rated voltage range of the TCON, by boosting the TCON core voltage, the output Swing voltage is increased so that the S-COF can correctly read the data, enabling the display panel to still be able to normally transmit and display the display data under interference, thereby improving the anti-mobile phone interference ability of the module. Refer to Figure 5a and Figure 5b , when the control circuit solution in the embodiment of the present invention is not used, when the TCON core voltage is 0.9V, the maximum output Swing voltage is 717.379mv, and its anti-interference ability is poor; while when the control circuit solution in the embodiment of the present invention is used, the TCON core voltage is 0.945V, and the maximum output Swing voltage is 786.228mv, and the anti-interference ability is improved. Therefore, using the control circuit in this embodiment can, on the premise of meeting the panel design power consumption, increase the output Swing voltage of the TCON when the core voltage of the timing controller itself is relatively small, so as to improve the anti-interference ability of the module and meet the requirements of the customer.

[0063] Based on the same inventive concept, on the other hand, an embodiment of the present invention further provides a display device, which includes the display panel as described above. Therefore, it also has the same technical effects as the foregoing embodiments.

[0064] Further, the display device may further include a power supply module, a support frame, and a sensor disposed in the support frame. The display panel and the power supply module are fixed to the support frame. The power supply module is disposed on the back surface of the display panel, that is, the non-display surface of the display panel. The power supply module is used to provide a power supply voltage for image display of the display panel. The support frame provides fixation and support for the display panel and the power supply module. The sensor is disposed in the support frame above the display device and is used to convert the sensed ambient light signal into a sensed signal and output the sensed signal to the display panel. The display panel performs image display with different brightness according to different ambient light signals. The sensor may adopt a photodiode, a phototransistor, or other photosensitive elements, which is not limited in this embodiment.

[0065] In other embodiments, when the display device is a portable electronic device, such as a mobile phone, a tablet computer, etc., the display device may not need to be provided with a support frame.

[0066] The beneficial effects of the present utility model are as follows: The present utility model provides a control circuit 100, a display panel, and a display device for a timing controller 200. The control circuit 100 accesses a control voltage signal Vb through the control terminal of a main switching transistor PM1 connected to the output port of the timing controller 200, connects the first end of the main switching transistor PM1 to a power supply module 300 to access a first voltage signal V1, and provides an output voltage signal Vout through the second end of the main switching transistor PM1. Then, in the first level state of the control voltage signal Vb, the voltage control circuit 110 is in an off state to maintain the output voltage signal Vout stable at the first voltage signal V1; or in the second level state of the control voltage signal Vb, the voltage control circuit 110 is in a conducting state to clamp the output voltage signal Vout stable at a preset voltage signal V3, and the preset voltage signal V3 changes following the potential of the first voltage signal V1. Thus, within the rated voltage range of the TCON, on the premise of meeting the design power consumption, by boosting the TCON core voltage, the output Swing voltage is increased, so that the input signal quality can be improved while the anti-interference ability of the display module is improved.

[0067] It should be noted that in the description of the present utility model, it should be understood that the terms "upper", "lower", "inner", etc. indicating the orientation or position relationship are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present utility model.

[0068] In addition, in this text, the terms "including", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements but also other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0069] Finally, it should be noted that: Obviously, the above embodiments are merely examples given to clearly illustrate the present utility model and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present utility model.

Claims

1. A control circuit for a timing controller, characterized in that, Comprising: A main switch transistor, the control terminal of the main switch transistor is connected to the output port of the timing controller to access a control voltage signal, the first terminal of the main switch transistor is connected to a power supply module to access a first voltage signal, and the second terminal of the main switch transistor serves as the output terminal of the control circuit to provide an output voltage signal; A voltage control circuit, the input terminal of the voltage control circuit is connected to the control terminal of the main switch transistor, and the output terminal of the voltage control circuit is connected to the second terminal of the main switch transistor, In the first level state of the control voltage signal, the voltage control circuit is turned off, and the output voltage signal is stabilized at the first voltage signal; or in the second level state of the control voltage signal, the voltage control circuit is turned on, and the output voltage signal is stabilized at a preset voltage signal, and the preset voltage signal changes following the change of the first voltage signal.

2. The control circuit according to claim 1, wherein In the first level state of the control voltage signal, the main switch transistor is turned on; In the second level state of the control voltage signal, the main switch transistor is turned off.

3. The control circuit according to claim 2, wherein The first level state of the control voltage signal is a low level state, and the second level state of the control voltage signal is a high level state; Or, the first level state of the control voltage signal is a high level state, and the second level state of the control voltage signal is a low level state.

4. The control circuit according to claim 2, wherein The voltage control circuit includes: A first resistor, a first switch transistor and a first constant voltage source, the first terminal of the first resistor is grounded, the second terminal of the first resistor is connected to the first terminal of the first switch transistor, the second terminal of the first switch transistor is connected to the first constant voltage source to ground, and the control terminal of the first switch transistor serves as the input terminal of the voltage control circuit and is connected to the control terminal of the main switch transistor; A second constant voltage source and a second switch transistor, the first terminal of the second constant voltage source is grounded, the second terminal of the second constant voltage source is connected to the first terminal of the second switch transistor, the second terminal of the second switch transistor serves as the output terminal of the voltage control circuit and is connected to the second terminal of the main switch transistor, and the control terminal of the second switch transistor is connected to the intermediate node between the first switch transistor and the first constant voltage source.

5. The control circuit according to claim 4, characterized in that In the first level state of the control voltage signal, both the first switch transistor and the second switch transistor are turned off; In the second level state of the control voltage signal, both the first switch transistor and the second switch transistor are turned on.

6. The control circuit according to claim 5, wherein The first constant voltage source is built in the power supply module to provide a second voltage signal; The second constant voltage source is the output node of a low dropout linear regulator to provide the preset voltage signal.

7. The control circuit according to claim 6, wherein Any one of the main switch transistor, the first switch transistor and the second switch transistor is a metal oxide semiconductor field effect transistor.

8. The control circuit according to claim 7, wherein Both the main switch transistor and the second switch transistor are P-channel metal oxide semiconductor field effect transistors, and the first switch transistor is an N-channel metal oxide semiconductor field effect transistor.

9. A display panel, characterized in that, Comprising: A plurality of sub-pixels arranged in an array in the display area; A timing controller, a source driver, and a gate driver. The timing controller performs conversion processing on display data, and then inputs signals related to gate driving to the gate driver and inputs signals related to source driving to the source driver. The control circuit for a timing controller according to any one of claims 1-8.

10. A display device, characterized in that, Comprising a display panel according to claim 9.

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