Driving circuit of display panel, driving method of display panel, and display device

Abstract

The application discloses a display panel driving circuit, a display panel driving method and a display device, and mainly relates to the technical field of display. The output end of a control board is connected with the input end of a boost circuit module, and the output end of the boost circuit is connected with the input end of a source electrode driving circuit module. The input end and the output end of a selection step-down circuit module are connected between the output end of the control board and the input end of the boost circuit module, or the input end and the output end of the selection step-down circuit module are connected between the output end of the boost circuit module and the input end of the source electrode driving circuit module. The selection step-down circuit module is used for reducing the standard voltage signal higher than or equal to the threshold voltage output by the control board to less than the threshold voltage and outputting the standard voltage signal, and directly outputting the standard voltage signal lower than the threshold voltage output by the control board. The above design is realized, the source electrode driving circuit module is prevented from heating, display failure problems are avoided, and the cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a display panel driving circuit, a display panel driving method and a display device. BACKGROUND

[0002] Most of the display screens used by current display devices are liquid crystal display screens, which are composed of liquid crystal panels and backlight sources. In order to make the liquid crystal display screen display normally, appropriate driving power needs to be provided for the liquid crystal panel and the backlight source respectively.

[0003] However, the existing display panel driving circuit has the problem of abnormal heating of the source driving circuit module. SUMMARY

[0004] The present application aims to provide a display panel driving circuit, a display panel driving method and a display device, which can prevent the source driving circuit module from heating, avoid display failure and reduce cost.

[0005] The present application discloses a display panel driving circuit, which comprises a control board, a selection voltage reduction circuit module, a voltage increase circuit module and a source driving circuit module.

[0006] The output end of the control board is connected with the input end of the voltage increase circuit module, and the output end of the voltage increase circuit is connected with the input end of the source driving circuit module.

[0007] The input end and the output end of the selection voltage reduction circuit module are connected between the output end of the control board and the input end of the voltage increase circuit module, or the input end and the output end of the selection voltage reduction circuit module are connected between the output end of the voltage increase circuit module and the input end of the source driving circuit module.

[0008] The selection voltage reduction circuit module is used for reducing the standard voltage signal output by the control board, which is higher than or equal to the threshold voltage, to less than the threshold voltage, and directly outputting the standard voltage signal output by the control board, which is lower than the threshold voltage.

[0009] Optionally, the input end of the selection voltage reduction circuit module is connected with the output end of the control board, and is used for receiving the standard voltage signal output by the control board. The output end of the selection voltage reduction circuit module is connected with the input end of the voltage increase circuit module.

[0010] Optionally, the selection voltage reduction circuit module comprises a selection control unit, a first control switch, a second control switch and a voltage reduction control unit.

[0011] The input end of the selection control unit is connected with the output end of the control board, and the output end of the selection control unit is connected with the control end of the first control switch and the control end of the second control unit;

[0012] The input end of the first control switch is connected with the output end of the control board, and the output end of the first control switch is connected with the input end of the boost circuit module;

[0013] The input end of the second control switch is connected with the output end of the control board, the output end of the second control switch is connected with the input end of the step-down control unit, and the output end of the step-down control unit is connected with the input end of the boost circuit module;

[0014] The selection control unit is used for selecting one of the first control switch and the second control switch to be opened and the other to be closed according to the relationship between the input standard voltage signal and the threshold voltage, and the step-down control unit is used for reducing the voltage value of the input signal higher than or equal to the threshold voltage.

[0015] Optionally, the selection control unit comprises a voltage stabilizing diode, a first resistor, a second resistor, a first N-type transistor and a second N-type transistor;

[0016] The negative electrode of the voltage stabilizing diode is connected with the output end of the control board, the positive electrode of the voltage stabilizing diode is connected with the control end of the first N-type transistor, one end of the first resistor is connected with the output end of the control board, the other end is connected with the input end of the first N-type transistor, and the output end of the first N-type transistor is grounded;

[0017] The control end of the second N-type transistor is connected between the first resistor and the input end of the first N-type transistor, one end of the second resistor is connected with the output end of the control board, the other end is connected with the input end of the second N-type transistor, and the output end of the second N-type transistor is grounded;

[0018] The first control switch comprises a first P-type transistor;

[0019] The control end of the first P-type transistor is connected between the second resistor and the input end of the second N-type transistor, the input end of the first P-type transistor is connected with the output end of the control board, and the output end of the first P-type transistor is connected with the input end of the boost circuit module;

[0020] The second control switch comprises a second P-type transistor;

[0021] The control end of the second P-type transistor is connected with the first resistor and the input end of the first N-type transistor, the input end of the second P-type transistor is connected with the output end of the control board.

[0022] The voltage reduction control unit comprises a voltage dividing resistor;

[0023] Two ends of the voltage dividing resistor are connected with an output end of the second P-type transistor and an input end of the voltage boosting circuit module respectively.

[0024] Optionally, the selection control unit comprises a voltage stabilizing diode, a first resistor, a second resistor, a first N-type transistor and a second N-type transistor;

[0025] A negative electrode of the voltage stabilizing diode is connected with an output end of the control board, a positive electrode of the voltage stabilizing diode is connected with a control end of the first N-type transistor, one end of the first resistor is connected with the output end of the control board, the other end is connected with an input end of the first N-type transistor, and an output end of the first N-type transistor is grounded;

[0026] A control end of the second N-type transistor is connected between the first resistor and the input end of the first N-type transistor, one end of the second resistor is connected with the output end of the control board, the other end is connected with an input end of the second N-type transistor, and an output end of the second N-type transistor is grounded;

[0027] The first control switch comprises a first P-type transistor;

[0028] A control end of the first P-type transistor is connected between the second resistor and the input end of the second N-type transistor, an input end of the first P-type transistor is connected with the output end of the control board, and an output end of the first P-type transistor is connected with the input end of the voltage boosting circuit module;

[0029] The second control switch comprises a second P-type transistor;

[0030] A control end of the second P-type transistor is connected with the first resistor and the input end of the first N-type transistor, and an input end of the second P-type transistor is connected with the output end of the control board;

[0031] The voltage reduction control unit comprises a first transistor;

[0032] An input end of the first transistor is connected with an output end of the second P-type transistor, and an output end of the first transistor is connected with an output end of the control board;

[0033] The control end of the first transistor is used for accepting a control signal to adjust a conduction resistance of the first transistor.

[0034] Optionally, the driving circuit of the display panel further comprises a first voltage adjustment module, a second voltage adjustment module, a first step-down conversion circuit, a second step-down conversion circuit and a gate driving circuit module.

[0035] The input end of the first voltage adjustment module is connected with the output end of the control board, and the output end of the first voltage adjustment module is connected with the input end of the gate driving circuit module.

[0036] The input end of the second voltage adjustment module is connected with the output end of the control board, and the output end of the second voltage adjustment module is connected with the input end of the gate driving circuit module.

[0037] The input end of the first step-down conversion circuit is connected with the output end of the control board, and the output end of the first step-down conversion circuit is connected with the input end of the source driving circuit module.

[0038] The input end of the second step-down conversion circuit is connected with the output end of the control board, and the output end of the second step-down conversion circuit is connected with the input end of the source driving circuit module.

[0039] The selection step-down circuit module is connected only between the control board and the step-up circuit module, or the selection step-down circuit module is connected only between the step-up circuit module and the source driving circuit module.

[0040] The first voltage adjustment module is used for generating a VGH signal; the second voltage adjustment module is used for generating a VGL signal; the first step-down conversion circuit is used for generating a Vlogic signal; the second step-down conversion circuit is used for generating a Vcore signal; and the selection step-down circuit module and the step-up circuit module are used together for generating a VAA voltage.

[0041] Optionally, the output voltage of the control board is 12V, the breakdown voltage of the voltage stabilizing diode is 12V, and the resistance value of the step-down control unit is set to 5 ohms.

[0042] The application further discloses a driving method of a display panel, which is used for driving a driving circuit of a display panel and comprises the following steps:

[0043] The control board outputs a standard voltage signal.

[0044] The selection step-down circuit module receives the standard voltage signal, when the standard voltage signal is higher than or equal to a threshold voltage, controls the voltage value of the standard voltage signal to be reduced to less than the threshold voltage and then outputs the standard voltage signal to the step-up circuit module; and when the standard voltage signal is less than the threshold voltage, directly outputs the standard voltage signal to the step-up circuit module.

[0045] The boost circuit module receives the voltage signal output by the selection buck circuit module and boosts the voltage signal output by the selection buck circuit module to a VAA voltage and outputs the VAA voltage to a source driving circuit module.

[0046] Optionally, the selection buck circuit module comprises a selection control unit, a first control switch, a second control switch and a buck control unit.

[0047] The selection buck circuit module receives the standard voltage signal, and when the standard voltage signal is higher than or equal to a threshold voltage, the voltage value of the standard voltage signal is controlled to be reduced to less than the threshold voltage before being output to the boost circuit module; when the standard voltage signal is less than the threshold voltage, the standard voltage signal is directly output to the boost circuit module, and the step comprises:

[0048] The selection control unit receives the standard voltage signal.

[0049] When the standard voltage signal is lower than the threshold voltage, the first control switch is controlled to be opened and the second control switch is controlled to be closed, and the standard voltage signal is directly output to the boost circuit module through the first control switch.

[0050] When the standard voltage signal is higher than or equal to the threshold voltage, the first control switch is controlled to be closed and the second control switch is controlled to be opened, and the standard voltage signal is output to the buck control unit through the second control switch, and the buck control unit reduces the standard voltage signal to less than or equal to the threshold signal before outputting the standard voltage signal to the boost circuit module.

[0051] The application also discloses a display device, which comprises a display panel and a driving circuit of the display panel.

[0052] Compared with the prior art, the selection buck circuit module is added to reduce the voltage entering the source driving circuit module, so that the difference between the voltage input into the source driving circuit module and the output voltage of the source driving circuit module is reduced, the problem of heat loss of the triode in the source driving circuit is avoided, the source driving circuit module is prevented from generating heat, and the display failure problem is avoided; and since a heat sink does not need to be attached to the source driving circuit module, the method can also reduce the cost. BRIEF DESCRIPTION OF DRAWINGS

[0053] The accompanying drawings, which are included to provide a further understanding of the embodiments and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It is to be understood that the drawings are solely for purposes of illustration and that other drawings can be derived from these drawings without paying creative labor. In the drawings:

[0054] Figure 1 is a schematic diagram of a display device according to an embodiment of the present application;

[0055] Figure 2 is a schematic diagram of a driving circuit of a display panel according to a first embodiment of the present application;

[0056] Figure 3 is a schematic diagram of a source driving circuit module according to a first embodiment of the present application;

[0057] Figure 4 is a schematic diagram of a source driving circuit module according to a first embodiment of the present application;

[0058] Figure 5 is a schematic diagram of a source driving circuit module according to a first embodiment of the present application;

[0059] Figure 6A is a schematic diagram of a simulation waveform diagram according to a first embodiment of the present application;

[0060] Figure 6B is a schematic diagram of a simulation waveform diagram according to a first embodiment of the present application;

[0061] Figure 6C is a schematic diagram of a simulation waveform diagram according to a first embodiment of the present application;

[0062] Figure 7 is a schematic diagram of a driving circuit of a display panel according to a second embodiment of the present application;

[0063] Figure 8 is a schematic diagram of a source driving circuit module according to a second embodiment of the present application;

[0064] Figure 9 is a schematic diagram of a source driving circuit module according to a second embodiment of the present application;

[0065] Figure 10 is a schematic diagram of a source driving circuit module according to a third embodiment of the present application;

[0066] Figure 11 is a schematic diagram of a driving method of a display panel according to an embodiment of the present application.

[0067] Wherein, 10, display device; 20, display panel; 30, drive circuit of display panel; 100, control board; 200, selection step-down circuit module; 210, selection control unit; 211, voltage stabilizing diode; 212, first resistor; 213, second resistor; 214, first N-type transistor; 215, second N-type transistor; 216, third resistor; 220, first control switch; 221, first P-type transistor; 230, second control switch; 231, second P-type transistor; 240, step-down control unit; 241, voltage dividing resistor; 242, first transistor; 243, control end 243 of first transistor; 250, step-up circuit module; 261, fourth resistor; 262, fifth resistor; 271, input end of selection step-down circuit module; 272, output end of selection step-down circuit module; 300, source driving circuit module; 310, source driving output circuit; 311, power supply input end; 312, digital to analog voltage signal input end; 313, first triode; 314, second triode; 315, data signal output end; 400, first voltage adjustment module; 500, second voltage adjustment module; 600, first step-down conversion circuit; 700, second step-down conversion circuit; 800, gate driving circuit module; 900, PWM control chip. DETAILED DESCRIPTION

[0068] It is to be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to be limiting. It is also possible that the application can be carried out in other ways than those specifically set forth herein without departing from the essence of the application.

[0069] In the description of the application, the terms "first", "second", "third", etc. are used only for descriptive purposes and are not to be construed as indicating relative importance or a number of indicated technical features. Thus, unless otherwise stated, features defined with "first", "second" or "third" can explicitly or implicitly include one or more of the features; the meaning of "a plurality" is two or more. The term "comprising" and any variation thereof means inclusive, not exclusive, and can have one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0070] In addition, the terms indicating the orientation or positional relationship of "center", "transverse", "upper", "lower", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like are described based on the orientation or relative position relationship shown in the drawings, and are only for the convenience of the simplified description of the application, and are not intended to indicate that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0071] In addition, unless specifically stated and limited otherwise, the terms "mounting", "connected", "connecting" should be interpreted broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, can be electrically connected; can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0072] The application will be described in detail below with reference to the accompanying drawings and optional embodiments.

[0073] Figure 1 is a schematic diagram of a display device according to an embodiment of the application, as Figure 1 As shown in the figure, the application discloses a display device 10, which comprises a display panel 20 and a display panel driving circuit 30 connected with the display panel 20 to provide driving signals for the display panel 20.

[0074] The application also discloses a display panel driving circuit 30, which can be used in the above-mentioned display device 10. For the display panel driving circuit 30, the application provides the following design, which is specifically introduced through several embodiments:

[0075] Embodiment 1:

[0076] Figure 2 is a schematic diagram of a display panel driving circuit according to a first embodiment of the application, as Figure 2 As shown in the figure, the application discloses a display panel driving circuit 30, which comprises a control board 100, a selection step-down circuit module 200, a step-up circuit module 250 and a source driving circuit module 300.

[0077] The output end of the control board 100 is connected with the input end of the step-up circuit module 250, and the output end of the step-up circuit is connected with the input end of the source driving circuit module 300.

[0078] The input end 271 and the output end 272 of the selection step-down circuit module are respectively connected between the output end of the control board 100 and the input end of the step-up circuit module 250, or the input end 271 and the output end 272 of the selection step-down circuit module are respectively connected between the output end of the step-up circuit module 250 and the input end of the source driving circuit module 300.

[0079] The input end 271 and the output end 272 of the selection voltage reduction circuit module are connected between the output end of the control board 100 and the input end of the voltage boosting circuit module 250.

[0080] The selection voltage reduction circuit module 200 is used to reduce the standard voltage signal output by the control board 100 to less than the threshold voltage and output the signal, while directly outputting the standard voltage signal output by the control board 100 which is less than the threshold voltage.

[0081] The existing general control board 100 is used to output a standard voltage signal, the voltage boosting circuit module 250 is a BOOST voltage boosting circuit used to generate a VAA voltage (analog power supply voltage), the source drive circuit module 300 generates a data signal according to the VAA voltage and outputs the data signal to the display panel 20, and the data signal is used to control the liquid crystal in the display panel 20 to deflect.

[0082] Figure 3 is a schematic diagram of a source drive circuit module according to the first embodiment of the present application, and Figures 2-3 As shown in the figure, the source drive circuit module 300 includes a plurality of source drive output circuits 310, and each source drive output circuit 310 includes a power supply input end 311, a digital-to-analog voltage signal input end 312, a first triode 313, a second triode 314, and a data signal output end 315.

[0083] The digital-to-analog voltage signal input end 312 is connected to the control end of the first triode 313 and the control end of the second triode 314, the input end of the first triode 313 is connected to the power supply input end 311, and in this embodiment, the input end of the first triode 313 is connected to the output end of the voltage boosting circuit module 250.

[0084] In another embodiment, when the selection voltage reduction circuit module 200 is arranged between the voltage boosting circuit module 250 and the source drive circuit module 300, the input end of the first triode 313 is connected to the output end 272 of the selection voltage reduction circuit module.

[0085] The output end of the first triode 313 is connected to the data signal output end 315, the input end of the second triode 314 is grounded, and the output end of the second triode 314 is connected to the output end of the first triode 313.

[0086] For example, the type of the first triode 313 can be an NPN triode, and the type of the second triode 314 can be a PNP triode.

[0087] The digital-to-analog voltage signal input terminal 312 inputs a digital-to-analog voltage signal, and the data signal output terminal 315 outputs a data voltage to the display panel 20, which is used to charge the pixel electrode and control the deflection of the liquid crystal.

[0088] The first transistor 313 and the second transistor 314 are controlled by the voltage input through the digital-to-analog voltage signal input terminal 312, so that the voltage of the data signal output by the data signal output terminal 315 is the same as the voltage of the digital-to-analog voltage signal input by the digital-to-analog voltage signal input terminal 312.

[0089] In short, the first transistor 313 and the second transistor 314 can be considered as variable resistors that change with the voltage of the digital-to-analog voltage signal, and the voltage of the data signal required by the display panel 20 is obtained under the voltage division of the first transistor 313 and the second transistor 314.

[0090] The applicant found that when the display device 10 is working, a large amount of heat will be generated on the source driving circuit module 300, and the source driving circuit module 300 is generally located beside the rubber frame of the display panel 20. If effective heat dissipation is not performed, the display panel 20 may be damaged when the local temperature is too high, and even there is a safety risk. Therefore, a heat dissipation sticker is attached to the source driving circuit module 300 before, but the heat dissipation sticker will increase the cost.

[0091] The applicant found that the main reason for the heat generated on the source driving circuit module 300 is that the VAA voltage output by the existing driving circuit of the display panel fluctuates and outputs a larger voltage, which is caused by the lower data signal required for driving the deflection of the liquid crystal in the display panel 20, as follows.

[0092] The standard voltage signal generated by the control board 100 is 12V, and the current boost circuit module 250 adopts a BOOST boost circuit. The main principle is to control the boost of the standard voltage signal through the PWM signal generated by the PWM control chip 900. However, due to the limitation of the PWM control chip 900, the voltage of the standard voltage signal generated by the control board 100 can only be about 1.14 times of the standard voltage signal 12V after being boosted by the boost circuit module 250, that is, the ideal VAA voltage is 13.68V. However, the standard voltage signal fluctuates by ±10%, so the actual standard voltage signal ranges from 10.8V to 13.2V, and the actual VAA voltage can only range from 12.312V to 15.048V.

[0093] Nowadays, with the low-voltage liquid crystal being used more and more widely, even if the voltage of liquid crystal deflection can be made lower and lower, the data signal of commonly used low-voltage liquid crystal can be reduced to work below 13V, and even 11V can realize deflection, so the voltage range of the ideal VAA voltage output by the existing boost circuit module 250 is 12.312~15.048V, which will cause the heat loss of the first transistor 313 and the second transistor 314 to be larger, thereby causing the heating problem of the source driving circuit module 300.

[0094] The voltage range value of the threshold voltage of the present application is less than or equal to the ideal VAA voltage / 1.14.

[0095] The present application reduces the voltage entering the source driving circuit module 300 by increasing the selection of the buck circuit module 200, thereby reducing the difference between the voltage input to the source driving circuit module 300 and the output voltage of the source driving circuit module 300, thereby avoiding the heat loss of the transistors inside the source driving voltage, thereby preventing the source driving circuit module 300 from heating and avoiding display failure problems; and without the need to paste a heat sink on the source driving circuit module 300, it can also reduce the cost.

[0096] Moreover, it is not necessary to improve the control board 100, and the scope of application of the present application is wider.

[0097] The driving circuit 30 of the display panel of the present application further comprises a first voltage adjustment module 400, a second voltage adjustment module 500, a first buck conversion circuit 600, a second buck conversion circuit 700 and a gate driving circuit module 800.

[0098] For example, the first voltage adjustment module 400 comprises a BOOST circuit or a Charge Pump circuit; the second voltage adjustment module 500 comprises a BUCK-BOOST circuit or a Charge Pump circuit; the first buck conversion circuit comprises a BUCK circuit; the second buck conversion circuit 700 comprises a BUCK circuit; and the gate driving circuit module 800 is a GDL circuit (Gate Driver less).

[0099] The input end of the first voltage adjustment module 400 is connected with the output end of the control board 100, and the output end of the first voltage adjustment module 400 is connected with the input end of the gate driving circuit module 800.

[0100] The input end of the second voltage adjustment module 500 is connected with the output end of the control board 100, and the output end of the second voltage adjustment module 500 is connected with the input end of the gate drive circuit module 800.

[0101] The input end of the first step-down conversion circuit 600 is connected with the output end of the control board 100, and the output end of the first step-down conversion circuit 600 is connected with the input end of the source drive circuit module 300.

[0102] The input end of the second step-down conversion circuit 700 is connected with the output end of the control board 100, and the output end of the second step-down conversion circuit 700 is connected with the input end of the source drive circuit module 300.

[0103] The first voltage adjustment module 400 is used for generating a VGH signal, the VGH signal is used for controlling the brightness and the gray scale of the display panel 20, and the VGH signal is usually a positive voltage. The second voltage adjustment module 500 is used for generating a VGL signal, the VGL signal is used for controlling the refreshing and switching of the liquid crystal display, and the VGL signal is usually a negative voltage.

[0104] The first step-down conversion circuit 600 is used for generating a Vlogic signal (logic voltage signal), the Vlogic signal is used for controlling the logic on-off of the internal digital circuit of the source drive circuit module 300 and the high-low level of the external interface, and the second step-down conversion circuit is used for generating a Vcore signal (core voltage signal), the Vcore signal is also used for controlling the logic on-off of the internal digital circuit of the source drive circuit module 300. The selection step-down circuit module 200 and the step-up circuit module 250 are used for generating a VAA voltage together.

[0105] The application connects the selection step-down circuit module 200 only between the control board 100 and the step-up circuit module 250 or only between the step-up circuit module 250 and the source drive circuit module 300, that is, the application only performs step-down processing on the VAA voltage which needs to be transmitted into the display panel 20, so that the increased selection step-down circuit module 200 does not affect the voltages of other circuit modules, and the display abnormal phenomenon is avoided.

[0106] The input end 271 of the selection step-down circuit module is connected with the output end of the control board 100, and is used for receiving the standard voltage signal output by the control board 100. The output end 272 of the selection step-down circuit module is connected with the input end of the step-up circuit module 250.

[0107] Compared with the scheme that the selection voltage reduction circuit module 200 is arranged between the voltage boosting circuit board and the source driving circuit module 300, the VAA voltage output by the voltage boosting circuit module 250 is more stable and has smaller fluctuation compared with the VAA voltage output by the selection voltage reduction circuit module 200.

[0108] Figure 4 is a modularized schematic diagram of a source driving circuit module of the first embodiment of the present application, as Figure 4 The selection voltage reduction circuit module 200 includes a selection control unit 210, a first control switch 220, a second control switch 230 and a voltage reduction control unit 240, an input end of the selection control unit 210 is connected with an output end of the control board 100, and output ends of the selection control unit 210 are connected with control ends of the first control switch 220 and the second control unit.

[0109] An input end of the first control switch 220 is connected with an output end of the control board 100, and an output end of the first control switch 220 is connected with an input end of the voltage boosting circuit module 250.

[0110] An input end of the second control switch 230 is connected with an output end of the control board 100, an output end of the second control switch is connected with an input end of the voltage reduction control unit 240, and an output end of the voltage reduction control unit 240 is connected with an input end of the voltage boosting circuit module 250.

[0111] The selection control unit 210 is configured to select one of the first control switch 220 and the second control switch 230 to be opened and the other to be closed according to a relationship between an input standard voltage signal and a threshold voltage, and the voltage reduction control unit 240 is configured to reduce a voltage value of an input signal higher than or equal to the threshold voltage.

[0112] When the selection control unit 210 detects that the input standard voltage signal is greater than or equal to the threshold voltage, the first control switch 220 is controlled to be closed and the second control switch 230 is controlled to be opened, so that the input standard voltage signal is output to the source driving circuit module 300 along the second control switch 230 and through the voltage reduction control unit 240, and the input standard voltage signal can be reduced to be less than the threshold voltage through voltage division of the voltage reduction control unit 240.

[0113] When the selection control unit 210 detects that the input standard voltage signal is less than the threshold voltage, the first control switch 220 is controlled to be opened and the second control switch 230 is controlled to be closed, so that the input standard voltage signal is directly output to the source driving circuit module 300 along the first control switch 220.

[0114] Figure 5is a schematic diagram of a source driving circuit module of a first embodiment of the present application, as Figure 5 As shown, specifically, the selection control unit 210 includes a zener diode 211, a first resistor 212, a second resistor 213, a first N-type transistor 214, and a second N-type transistor 215.

[0115] The negative electrode of the zener diode 211 is connected to the output end of the control board 100, the positive electrode of the zener diode 211 is connected to the control end of the first N-type transistor 214, one end of the first resistor 212 is connected to the output end of the control board 100, the other end is connected to the input end of the first N-type transistor 214, and the output end of the first N-type transistor 214 is grounded; the first N-type transistor 214 is an NMOS transistor, which is turned off at a low level and turned on at a high level.

[0116] The control end of the second N-type transistor 215 is connected between the first resistor 212 and the input end of the first N-type transistor 214, one end of the second resistor 213 is connected to the output end of the control board 100, the other end is connected to the input end of the second N-type transistor 215, and the output end of the second N-type transistor 215 is grounded; the second N-type transistor 215 is an NMOS transistor, which is turned off at a low level and turned on at a high level.

[0117] The first control switch 220 includes a first P-type transistor 221; the first P-type transistor 221 is a PMOS transistor, which is turned on at a low level and turned off at a high level.

[0118] The control end of the first P-type transistor 221 is connected between the second resistor 213 and the input end of the second N-type transistor 215, the input end of the first P-type transistor 221 is connected to the output end of the control board 100, and the output end of the first P-type transistor 221 is connected to the input end of the boost circuit module 250.

[0119] The second control switch 230 includes a second P-type transistor 231; the second P-type transistor 231 is a PMOS transistor, which is turned on at a low level and turned off at a high level.

[0120] The control end of the second P-type transistor 231 is connected to the input end of the first resistor 212 and the first N-type transistor 214, and the input end of the second P-type transistor 231 is connected to the output end of the control board 100.

[0121] The voltage reduction control unit 240 comprises a voltage dividing resistor 241; the voltage dividing resistor 241 performs voltage dividing processing on the standard voltage signal; two ends of the voltage dividing resistor 241 are respectively connected with an output end of the second P-type transistor 231 and an input end of the voltage boosting circuit module 250.

[0122] The voltage stabilizing diode 211 is used to avoid current equal to or greater than the threshold voltage being directly output from the first P-type transistor 221; for example, the breakdown voltage of the voltage stabilizing diode 211 is equal to the threshold voltage.

[0123] Further, the selection control unit 210 can further comprise a third resistor 216, and the selection voltage reduction circuit module 200 further comprises a fourth resistor 261 and a fifth resistor 262; one end of the third resistor 216 is connected with the anode of the voltage stabilizing diode 211, and the other end is grounded; the control end of the first N-type transistor 214 is connected between the third resistor 216 and the anode of the voltage stabilizing diode 211; two ends of the fourth resistor 261 are respectively connected between the input end and the control end of the first control switch 220; two ends of the fifth resistor 262 are respectively connected between the input end and the control end of the second control switch 230.

[0124] The third resistor 216 is used to generate a voltage at Va when the voltage stabilizing diode 211 is reversely broken down and conducts, so that the first N-type transistor 214 is turned on when the voltage at Va is greater than the turn-on voltage of the first N-type transistor 214; the fourth resistor 261 is used to prevent the first P-type transistor 221 from being mistakenly turned on; and the fifth resistor 262 is used to prevent the second P-type transistor 231 from being mistakenly turned on.

[0125] The voltage stabilizing diode 211 with a breakdown voltage less than or equal to the ideal VAA voltage / 1.14 is selected as the voltage stabilizing diode of the present application.

[0126] When the voltage input from the input end 271 of the selection voltage reduction circuit module is greater than or equal to the breakdown voltage of the voltage stabilizing diode 211, the voltage stabilizing diode 211 is broken down at this time, the Va voltage is pulled high, the first N-type transistor 214 is turned on, the Vb voltage is equal to 0V, the second N-type transistor 215 is turned off; the voltage at Vc is pulled high, the first P-type transistor 221 is turned off, and the second P-type transistor 231 is turned on, so that the voltage input from the input end 271 of the selection voltage reduction circuit module is output through the voltage dividing resistor 241.

[0127] When the voltage entering from the input terminal 271 of the selection voltage reduction circuit module is less than the breakdown voltage of the voltage stabilizing diode 211, at this time the voltage stabilizing diode 211 is not broken down, the voltage at Va is equal to OV, the first N-type transistor 214 is closed, the voltage at Vb is pulled high, the second N-type transistor 215 is opened, the voltage at Vc is equal to OV, the first P-type transistor 221 is opened, and the second P-type transistor 231 is closed, then the voltage entering from the input terminal 271 of the selection voltage reduction circuit module is directly outputted from the first P-type transistor 221.

[0128] Figure 6A is a schematic diagram of a simulation waveform of the first embodiment of the present application, Figure 6B is a schematic diagram of a simulation waveform of the first embodiment of the present application, Figure 6C is a schematic diagram of a simulation waveform of the first embodiment of the present application, as Figures 6A-6C shown, Figure 6A the abscissa represents time, and the ordinate represents voltage, Figure 6A the solid line M1 in indicates the relationship between the voltage signal entering from the input terminal of the selection voltage reduction circuit module 200 and time, and the solid line M2 indicates the relationship between the voltage signal outputted from the output terminal of the selection voltage reduction circuit module 200 and time; Figure 6B is the relationship between the conduction current of the first control switch 220 and time, the abscissa represents time, and the ordinate represents current; Figure 6C is the relationship between the conduction current of the second control switch 230 and time, the abscissa represents time, and the ordinate represents current.

[0129] For example, the output voltage of the control board 100 is 12V, the breakdown voltage of the voltage stabilizing diode 211 is 12V, and the resistance value of the voltage reduction control unit 240 is set to 5 ohms.

[0130] The simulation of the present circuit is carried out, the standard voltage signal is gradually increased from 10V to 15V, the breakdown voltage of the voltage stabilizing diode 211 is 12V, and the resistance value of the voltage reduction control unit 240 is set to 5 ohms. When the standard voltage signal is increased to 12V, the voltage stabilizing diode 211 is broken down, at the same time the first control switch 220 is closed, the second control switch 230 is opened, and the voltage signal entering from the input terminal of the selection voltage reduction circuit module 200 is reduced and outputted from the output terminal of the selection voltage reduction circuit module 200.

[0131] Second Embodiment:

[0132] Figure 7 is a schematic diagram of a driving circuit of a display panel of the second embodiment of the present application, Figure 8 is a modularized schematic diagram of a source driving circuit module of the second embodiment of the present application, Figure 9is a schematic diagram of a source driving circuit module of a second embodiment of the present application, as Figures 7-9 The difference between the first embodiment and the second embodiment is that the voltage reduction control unit 240 of the second embodiment comprises a controllable resistor, specifically, the selection control unit 210 comprises a voltage stabilizing diode 211, a first resistor 212, a second resistor 213, a first N-type transistor 214 and a second N-type transistor 215.

[0133] The negative electrode of the voltage stabilizing diode 211 is connected to the output terminal of the control board 100, the positive electrode of the voltage stabilizing diode 211 is connected to the control terminal of the first N-type transistor 214, one end of the first resistor 212 is connected to the output terminal of the control board 100, the other end is connected to the input terminal of the first N-type transistor 214, and the output terminal of the first N-type transistor 214 is grounded.

[0134] The control terminal of the second N-type transistor 215 is connected between the first resistor 212 and the input terminal of the first N-type transistor 214, one end of the second resistor 213 is connected to the output terminal of the control board 100, the other end is connected to the input terminal of the second N-type transistor 215, and the output terminal of the second N-type transistor 215 is grounded.

[0135] The first control switch 220 comprises a first P-type transistor 221, the control terminal of the first P-type transistor 221 is connected between the second resistor 213 and the input terminal of the second N-type transistor 215, the input terminal of the first P-type transistor 221 is connected to the output terminal of the control board 100, and the output terminal of the first P-type transistor 221 is connected to the input terminal of the voltage boosting circuit module 250.

[0136] The second control switch 230 comprises a second P-type transistor 231, the control terminal of the second P-type transistor 231 is connected to the first resistor 212 and the input terminal of the first N-type transistor 214, and the input terminal of the second P-type transistor 231 is connected to the output terminal of the control board 100.

[0137] The voltage reduction control unit 240 comprises a first transistor 242, the input terminal of the first transistor 242 is connected to the output terminal of the second P-type transistor 231, and the output terminal of the first transistor 242 is connected to the output terminal of the control board 100.

[0138] The control terminal 243 of the first transistor is used to receive a control signal to adjust the on-resistance of the first transistor 242.

[0139] The first transistor 242 comprises an NMOS transistor or a PMOS transistor. The control end 243 of the first transistor can receive a signal generated by the PWM control chip 900 to change the on-resistance of the first transistor 242, so that the on-resistance of the first transistor 242 can be controlled in a programmatic manner. That is, the driving circuit 30 of the display panel further comprises a PWM control chip 900, and the PWM control chip 900 is connected to the control end 243 of the first transistor.

[0140] Compared with the scheme in which the voltage reduction control unit 240 directly adopts the voltage dividing resistor 241 in the first embodiment, the scheme in this embodiment can change the on-resistance of the first transistor 242 through the PWM control chip 900, so that the program control is more flexible, and the voltage dividing resistor 241 does not need to be replaced when the output VAA voltage needs to be adjusted.

[0141] Embodiment 3

[0142] Figure 10 FIG. 3 is a schematic diagram of a source driving circuit module according to a third embodiment of the present application, as shown in the figure, different from the first embodiment, the input end 271 and the output end 272 of the selection voltage reduction circuit module are respectively connected between the output end of the voltage boosting circuit module 250 and the input end of the source driving circuit module 300. Figure 10

[0143] Specifically, the input end 271 of the selection voltage reduction circuit module is connected to the output end of the voltage boosting circuit, for receiving a standard voltage signal output by the control board 100 and boosted by the voltage boosting circuit module 250, and the output end 272 of the selection voltage reduction circuit module is connected to the input end of the source driving circuit module 300, so as to transmit the VAA voltage to the source driving circuit module 300.

[0144] Figure 11 FIG. 5 is a schematic diagram of a driving method of a display panel according to an embodiment of the present application, as shown in the figure, the present application also discloses a driving method of a display panel 20, the driving method of the display panel 20 is used for driving the driving circuit 30 of the display panel, and the driving method of the display panel 20 comprises the steps of: Figure 11

[0145] S1: The control board outputs a standard voltage signal.

[0146] ​​S2: the selection voltage reduction circuit module receives the standard voltage signal, when the standard voltage signal is higher than or equal to a threshold voltage, the voltage value of the standard voltage signal is reduced to less than the threshold voltage and then output to the voltage increase circuit module; when the standard voltage signal is less than the threshold voltage, the standard voltage signal is directly output to the voltage increase circuit module;

[0147] S3: the voltage increase circuit module receives the voltage signal output by the selection voltage reduction circuit module, and performs voltage increase processing on the voltage signal output by the selection voltage reduction circuit module to obtain a VAA voltage, and outputs the VAA voltage to the source driving circuit module.

[0148] The application reduces the difference between the voltage input to the source driving circuit module 300 and the output voltage of the source driving circuit module 300 by adding the selection voltage reduction circuit module 200, thereby avoiding heat loss of the triode inside the source driving voltage, preventing the source driving circuit module 300 from heating, and avoiding display failure problems; and the source driving circuit module 300 does not need to be attached with a heat sink, which also reduces the cost.

[0149] Further, the selection voltage reduction circuit module 200 includes a selection control unit 210, a first control switch 220, a second control switch 230, and a voltage reduction control unit 240.

[0150] S2: the selection voltage reduction circuit module receives the standard voltage signal, when the standard voltage signal is higher than or equal to a threshold voltage, the voltage value of the standard voltage signal is reduced to less than the threshold voltage and then output to the voltage increase circuit module; when the standard voltage signal is less than the threshold voltage, the standard voltage signal is directly output to the voltage increase circuit module.

[0151] S21: the selection control unit receives the standard voltage signal.

[0152] S22: when the standard voltage signal is lower than the threshold voltage, the first control switch is controlled to be opened and the second control switch is controlled to be closed, and the standard voltage signal is directly output to the voltage increase circuit module through the first control switch.

[0153] S23: when the standard voltage signal is higher than or equal to the threshold voltage, the first control switch is controlled to be closed and the second control switch is controlled to be opened, and the standard voltage signal is output to the voltage reduction control unit through the second control switch, and the voltage reduction control unit reduces the standard voltage signal to less than or equal to the threshold signal and then outputs the voltage signal to the voltage increase circuit module.

[0154] Thus, the standard voltage signal output by the control board 100 and higher than the threshold voltage is stepped down and then processed by the voltage boosting circuit module 250 to output the required VAA voltage.

[0155] The technical solution of the present application can be widely used in various display panels, such as TN (Twisted Nematic), IPS (In-Plane Switching), VA (Vertical Alignment), and MVA (Multi-Domain Vertical Alignment) display panels, all of which can be applied to the above-mentioned solution.

[0156] It should be noted that the steps involved in the present solution are not limited to the order of execution, as long as the specific solution can be implemented. The steps can be executed in the order described above, or in the reverse order, or even simultaneously. Any combination of the above-described embodiments or technical features, without conflict, shall be considered within the scope of the present application.

[0157] It should be noted that the inventive concept of the present application can form a very large number of embodiments, but the length of the application file is limited and cannot list them all. Therefore, on the premise of not conflicting, the above-described embodiments or technical features can be combined to form new embodiments. The combination of each embodiment or technical feature will enhance the original technical effect.

[0158] The above is a further detailed description of the present application in combination with specific optional embodiments, and the specific implementation of the present application should not be limited to these descriptions. For ordinary skilled persons in the art to which the present application belongs, without departing from the concept of the present application, a number of simple deductions or substitutions can be made, which should be considered within the scope of protection of the present application.

Claims

1. A drive circuit of a display panel, characterized by, The driving circuit of the display panel comprises a control board, a selection voltage reduction circuit module, a voltage increase circuit module and a source driving circuit module; The output end of the control board is connected with the input end of the voltage increase circuit module, and the output end of the voltage increase circuit is connected with the input end of the source driving circuit module; The input end and the output end of the selection voltage reduction circuit module are connected between the output end of the control board and the input end of the voltage increase circuit module, respectively; The selection voltage reduction circuit module is used for reducing the standard voltage signal output by the control board to less than the threshold voltage and outputting the standard voltage signal, and directly outputting the standard voltage signal lower than the threshold voltage output by the control board; The input end of the selection voltage reduction circuit module is connected with the output end of the control board, and is used for receiving the standard voltage signal output by the control board, and the output end of the selection voltage reduction circuit module is connected with the input end of the voltage increase circuit module; The selection voltage reduction circuit module comprises a selection control unit, a first control switch, a second control switch and a voltage reduction control unit; The input end of the selection control unit is connected with the output end of the control board, and the output end of the selection control unit is connected with the control end of the first control switch and the control end of the second control unit; The input end of the first control switch is connected with the output end of the control board, and the output end of the first control switch is connected with the input end of the voltage increase circuit module; The input end of the second control switch is connected with the output end of the control board, the output end of the second control switch is connected with the input end of the voltage reduction control unit, and the output end of the voltage reduction control unit is connected with the input end of the voltage increase circuit module; The selection control unit is used for selecting one of the first control switch and the second control switch to be opened and the other to be closed according to the relationship between the input standard voltage signal and the threshold voltage, and the voltage reduction control unit is used for reducing the voltage value of the input signal higher than or equal to the threshold voltage.

2. The driving circuit of the display panel according to claim 1, wherein The selection control unit comprises a voltage stabilizing diode, a first resistor, a second resistor, a first N-type transistor and a second N-type transistor; The negative electrode of the voltage stabilizing diode is connected with the output end of the control board, the positive electrode of the voltage stabilizing diode is connected with the control end of the first N-type transistor, one end of the first resistor is connected with the output end of the control board, the other end is connected with the input end of the first N-type transistor, and the output end of the first N-type transistor is grounded; The control end of the second N-type transistor is connected between the first resistor and the input end of the first N-type transistor, one end of the second resistor is connected with the output end of the control board, the other end is connected with the input end of the second N-type transistor, and the output end of the second N-type transistor is grounded; The first control switch comprises a first P-type transistor; The control end of the first P-type transistor is connected between the second resistor and the input end of the second N-type transistor, the input end of the first P-type transistor is connected with the output end of the control board, and the output end of the first P-type transistor is connected with the input end of the voltage increase circuit module. The second control switch comprises a second P-type transistor; The control end of the second P-type transistor is connected with the first resistor and the input end of the first N-type transistor, and the input end of the second P-type transistor is connected with the output end of the control board; The voltage reduction control unit comprises a voltage dividing resistor; The two ends of the voltage dividing resistor are respectively connected with the output end of the second P-type transistor and the input end of the voltage boosting circuit module.

3. The driving circuit of the display panel according to claim 1, wherein The selection control unit comprises a voltage stabilizing diode, a first resistor, a second resistor, a first N-type transistor and a second N-type transistor; The negative electrode of the voltage stabilizing diode is connected with the output end of the control board, the positive electrode of the voltage stabilizing diode is connected with the control end of the first N-type transistor, one end of the first resistor is connected with the output end of the control board, and the other end is connected with the input end of the first N-type transistor, and the output end of the first N-type transistor is grounded; The control end of the second N-type transistor is connected between the first resistor and the input end of the first N-type transistor, one end of the second resistor is connected with the output end of the control board, and the other end is connected with the input end of the second N-type transistor, and the output end of the second N-type transistor is grounded; The first control switch comprises a first P-type transistor; The control end of the first P-type transistor is connected between the second resistor and the input end of the second N-type transistor, the input end of the first P-type transistor is connected with the output end of the control board, and the output end of the first P-type transistor is connected with the input end of the voltage boosting circuit module; The second control switch comprises a second P-type transistor; The control end of the second P-type transistor is connected with the first resistor and the input end of the first N-type transistor, and the input end of the second P-type transistor is connected with the output end of the control board; The voltage reduction control unit comprises a first transistor; The input end of the first transistor is connected with the output end of the second P-type transistor, and the output end of the first transistor and the output end of the control board are connected; The control end of the first transistor is used for receiving a control signal to adjust the on-resistance of the first transistor.

4. The driving circuit of a display panel according to claim 1, wherein The driving circuit of the display panel further comprises a first voltage adjustment module, a second voltage adjustment module, a first voltage reduction conversion circuit, a second voltage reduction conversion circuit and a gate driving circuit module; The input end of the first voltage adjustment module is connected with the output end of the control board, and the output end of the first voltage adjustment module is connected with the input end of the gate driving circuit module; The input end of the second voltage adjustment module is connected with the output end of the control board, and the output end of the second voltage adjustment module is connected with the input end of the gate driving circuit module; The input end of the first voltage reduction conversion circuit is connected with the output end of the control board, and the output end of the first voltage reduction conversion circuit is connected with the input end of the source driving circuit module; The input end of the second voltage reduction conversion circuit is connected with the output end of the control board, and the output end of the second voltage reduction conversion circuit is connected with the input end of the source driving circuit module; The selection voltage reduction circuit module is connected only between the control board and the voltage increase circuit module; The first voltage adjustment module is configured to generate a VGH signal; the second voltage adjustment module is configured to generate a VGL signal; the first voltage reduction conversion circuit is configured to generate a Vlogic signal; the second voltage reduction conversion circuit is configured to generate a Vcore signal; and the selection voltage reduction circuit module and the voltage increase circuit module are collectively configured to generate a VAA voltage.

5. The driving circuit of the display panel according to claim 2 or 3, wherein The output voltage of the control board is 12V, the breakdown voltage of the voltage stabilizing diode is 12V, and the resistance value of the voltage reduction control unit is set to 5 ohms.

6. A drive circuit of a display panel, characterized by comprising: The driving circuit of the display panel comprises a control board, a selection voltage reduction circuit module, a voltage increase circuit module, and a source driving circuit module; The output end of the control board is connected with the input end of the voltage increase circuit module, and the output end of the voltage increase circuit is connected with the input end of the source driving circuit module; The input end and the output end of the selection voltage reduction circuit module are connected between the output end of the voltage increase circuit module and the input end of the source driving circuit module, respectively; The selection voltage reduction circuit module is configured to reduce the standard voltage signal output by the control board, which is higher than or equal to a threshold voltage, to less than the threshold voltage, and output the standard voltage signal, and directly output the standard voltage signal output by the control board, which is lower than the threshold voltage; The input end of the selection voltage reduction circuit module is connected with the output end of the voltage increase circuit module, configured to receive the standard voltage signal output by the control board, and the output end of the selection voltage reduction circuit module is connected with the input end of the source driving circuit module; The selection voltage reduction circuit module comprises a selection control unit, a first control switch, a second control switch, and a voltage reduction control unit; The input end of the selection control unit is connected with the output end of the voltage increase circuit module, and the output end of the selection control unit is connected with the control end of the first control switch and the control end of the second control unit; The input end of the first control switch is connected with the output end of the control board, and the output end of the first control switch is connected with the input end of the voltage increase circuit module; The input end of the second control switch is connected with the output end of the control board, the output end of the second control switch is connected with the input end of the voltage reduction control unit, and the output end of the voltage reduction control unit is connected with the input end of the source driving circuit module; The selection control unit is configured to select one of the first control switch and the second control switch to be opened and the other to be closed according to the relationship between the input standard voltage signal and the threshold voltage, and the voltage reduction control unit is configured to reduce the voltage value of the input signal higher than or equal to the threshold voltage.

7. A driving method of a display panel, characterized by, The driving method of the display panel is configured to drive the driving circuit of the display panel as claimed in any one of claims 1-6, and the driving method of the display panel comprises the steps of: The control board outputs a standard voltage signal; The selection voltage reduction circuit module receives the standard voltage signal, and when the standard voltage signal is higher than or equal to a threshold voltage, controls the voltage value of the standard voltage signal to be reduced to less than the threshold voltage and then output to the voltage increase circuit module; when the standard voltage signal is less than the threshold voltage, directly outputs the standard voltage signal to the voltage increase circuit module. The voltage increase circuit module receives the voltage signal output by the selection voltage reduction circuit module, and performs voltage increase processing on the voltage signal output by the selection voltage reduction circuit module to be a VAA voltage, and outputs to a source driving circuit module.

8. The driving method of the display panel according to claim 7, wherein The selection voltage reduction circuit module comprises a selection control unit, a first control switch, a second control switch, and a voltage reduction control unit. The selection voltage reduction circuit module receives the standard voltage signal, and when the standard voltage signal is higher than or equal to a threshold voltage, controls the voltage value of the standard voltage signal to be reduced to less than the threshold voltage and then output to the voltage increase circuit module; when the standard voltage signal is less than the threshold voltage, directly outputs the standard voltage signal to the voltage increase circuit module. The step of directly outputting the standard voltage signal to the voltage increase circuit module when the standard voltage signal is less than the threshold voltage comprises: The selection control unit receives the standard voltage signal; When the standard voltage signal is lower than the threshold voltage, controls the first control switch to be opened and the second control switch to be closed, and the standard voltage signal is directly output to the voltage increase circuit module through the first control switch; When the standard voltage signal is higher than or equal to the threshold voltage, controls the first control switch to be closed and the second control switch to be opened, and the standard voltage signal is output to the voltage reduction control unit through the second control switch, and the voltage reduction control unit reduces the standard voltage signal to be less than or equal to the threshold signal and then outputs to the voltage increase circuit module.

9. A display device, characterized by comprising: The display device comprises a display panel and a driving circuit of the display panel as claimed in any one of claims 1-6, the driving circuit of the display panel is connected with the display panel, and provides a driving signal for the display panel.

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