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WO2022188197A1 - 一种背光驱动电路及液晶显示装置 - Google Patents

一种背光驱动电路及液晶显示装置 Download PDF

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Publication number
WO2022188197A1
WO2022188197A1 PCT/CN2021/081280 CN2021081280W WO2022188197A1 WO 2022188197 A1 WO2022188197 A1 WO 2022188197A1 CN 2021081280 W CN2021081280 W CN 2021081280W WO 2022188197 A1 WO2022188197 A1 WO 2022188197A1
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WO
WIPO (PCT)
Prior art keywords
light
transistor
emitting
liquid crystal
backlight
Prior art date
Application number
PCT/CN2021/081280
Other languages
English (en)
French (fr)
Inventor
刘金风
Original Assignee
Tcl华星光电技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tcl华星光电技术有限公司 filed Critical Tcl华星光电技术有限公司
Priority to US17/281,122 priority Critical patent/US11967288B2/en
Publication of WO2022188197A1 publication Critical patent/WO2022188197A1/zh

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Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/3406—Control of illumination source
    • G09G3/342—Control of illumination source using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/3406—Control of illumination source
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G09G3/3611—Control of matrices with row and column drivers
    • G09G3/3685—Details of drivers for data electrodes
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/0237—Switching ON and OFF the backlight within one frame
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/024—Scrolling of light from the illumination source over the display in combination with the scanning of the display screen
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/08—Details of timing specific for flat panels, other than clock recovery
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/0257—Reduction of after-image effects
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals

Definitions

  • the present application relates to the field of display technology, and in particular, to a backlight driving circuit and a liquid crystal display device.
  • Liquid Crystal Display uses voltage to control the flip angle of the liquid crystal to control the screen to display different images.
  • higher and higher refresh rates in the process of liquid crystal flip, if the liquid crystal flip has not reached the When the backlight is always on in a steady state, the human eye will see the problem of smearing.
  • the inventor of the present application found that the image quality evaluation of some display panels requires the display to support full-frame black insertion (Black Frame Insertion, BFI) function, requires the backlight to insert black in the whole frame when the LCD panel (open cell, OC) is scanned, and the backlight is turned on after the LCD is turned over to a steady state after scanning.
  • BFI Black Frame Insertion
  • AMMini-led Active Matrix Mini light-emitting diode
  • the present application provides a backlight driving circuit and a liquid crystal display device, which can realize the whole frame black insertion of an active matrix liquid crystal display, so as to improve the display effect and improve the problem of smearing of the display screen.
  • the present application provides a backlight driving circuit, including:
  • the light-emitting device is connected in series to the light-emitting circuit formed by the first power supply signal and the second power supply signal;
  • a driving transistor, the source and drain of the driving transistor are connected in series with the light-emitting circuit, the gate of the driving transistor is electrically connected to the first node, and the driving transistor is used to control the light-emitting circuit flowing through the light-emitting circuit. current;
  • a data signal is written to the transistor, the source of the data signal is written to a data signal, the drain of the data signal is written to the transistor is electrically connected to the first node, and the gate of the data signal is written to the transistor Pole access scanning signal;
  • a storage capacitor a first end of the storage capacitor is electrically connected to the first node, and a second end of the storage capacitor is connected to the second power supply signal;
  • a lighting control module which is connected to a lighting control signal and connected to the lighting circuit in series, is used to control the lighting circuit to be turned on or off based on the lighting control signal.
  • the lighting control module includes a lighting control transistor
  • the source of the light-emitting control transistor is connected to the first power supply signal, the drain of the light-emitting control transistor is electrically connected to the light-emitting device, and the gate of the light-emitting control transistor is connected to the enable signal.
  • the combination of the scan signal and the enable signal sequentially corresponds to a scan phase, a display phase, and a black insertion phase.
  • the scan signal in the scan phase, is at a high level, and the enable signal is at a low level.
  • the scan signal is at a low level
  • the enable signal is at a high level
  • the scan signal is at a low level
  • the enable signal is at a low level
  • the data signal writing transistor, the light-emitting control transistor, and the driving transistor are all low-temperature polysilicon thin film transistors.
  • the data signal writing transistor, the light-emitting control transistor, and the driving transistor are all oxide semiconductor thin film transistors.
  • the data signal writing transistor, the light-emitting control transistor, and the driving transistor are all amorphous silicon thin film transistors.
  • the light-emitting device is a light-emitting diode
  • the drain of the light-emitting control transistor is electrically connected to the anode of the light-emitting diode.
  • the present application also provides a liquid crystal display device, comprising a backlight module, an array substrate, a color filter substrate, and a liquid crystal layer disposed between the array substrate and the color filter substrate, and the backlight module is disposed on the The side of the array substrate away from the liquid crystal layer, the backlight module is provided with a backlight drive circuit, and the backlight drive circuit includes:
  • the light-emitting device is connected in series to the light-emitting circuit formed by the first power supply signal and the second power supply signal;
  • a driving transistor, the source and drain of the driving transistor are connected in series with the light-emitting circuit, the gate of the driving transistor is electrically connected to the first node, and the driving transistor is used to control the light-emitting circuit flowing through the light-emitting circuit. current;
  • a data signal is written to the transistor, the source of the data signal is written to a data signal, the drain of the data signal is written to the transistor is electrically connected to the first node, and the gate of the data signal is written to the transistor Pole access scanning signal;
  • a storage capacitor a first end of the storage capacitor is electrically connected to the first node, and a second end of the storage capacitor is connected to the second power supply signal;
  • a lighting control module the lighting control module is connected to an enable signal and connected in series with the lighting circuit, and the lighting control module is used to control the lighting circuit to be turned on or off based on the enable signal.
  • the driving sequence of the backlight driving circuit includes a scanning phase, a display phase, and a black insertion phase.
  • the scanning phase the liquid crystal in the liquid crystal layer is deflected line by line
  • the display stage the deflection of the liquid crystal layer is stable
  • the backlight driving circuit drives the backlight module to emit light, so that the liquid crystal display device can display a normal screen.
  • the black insertion stage the backlight driving circuit controls The backlight module is turned off.
  • the scan signal in the scan phase, is at a high level, and the enable signal is at a low level.
  • the scan signal is at a low level
  • the enable signal is at a high level
  • the scan signal is at a low level
  • the enable signal is at a low level
  • the lighting control module includes a lighting control transistor
  • the source of the light-emitting control transistor is connected to the first power supply signal, the drain of the light-emitting control transistor is electrically connected to the light-emitting device, and the gate of the light-emitting control transistor is connected to the enable signal.
  • the data signal writing transistor, the light-emitting control transistor, and the driving transistor are all low-temperature polysilicon thin film transistors.
  • the data signal writing transistor, the light-emitting control transistor, and the driving transistor are all oxide semiconductor thin film transistors.
  • the data signal writing transistor, the light-emitting control transistor, and the driving transistor are all amorphous silicon thin film transistors.
  • the present application provides a backlight driving circuit and a liquid crystal display device.
  • the present application adds a light-emitting control module to the backlight driving circuit, and the light-emitting control module can be used to control the lighting or extinguishing of the light-emitting device, so as to realize the black insertion of the backlight of the liquid crystal display device frame by frame. , to meet the functional requirements of BFI and improve product quality.
  • FIG. 1 is a schematic structural diagram of a backlight driving circuit provided by the present application.
  • Fig. 2 is the first circuit schematic diagram of the backlight driving circuit provided by the present application.
  • Fig. 3 is the second circuit schematic diagram of the backlight driving circuit provided by the present application.
  • Fig. 4 is the third circuit schematic diagram of the backlight driving circuit provided by the present application.
  • FIG. 6 is a schematic diagram of the passage of the backlight driving circuit provided by the present application in the scanning stage t1 under the driving sequence shown in FIG. 5;
  • FIG. 7 is a schematic diagram of the path of the backlight driving circuit provided by the present application in the display stage t2 under the driving sequence shown in FIG. 5;
  • FIG. 8 is a schematic diagram of the path of the backlight driving circuit provided by the present application in the black insertion stage t3 under the driving sequence shown in FIG. 5;
  • FIG. 9 is a schematic structural diagram of a liquid crystal display device provided by the present application.
  • FIG. 10 is a timing diagram of a driving circuit of the backlight module provided by the present application.
  • the source and drain of the transistor used in this application are symmetrical, the source and drain thereof are interchangeable.
  • one electrode is called the source electrode, and the other electrode is called the drain electrode.
  • the transistors used in the present application may include P-type transistors and/or N-type transistors, wherein the P-type transistor is turned on when the gate is at a low level and turned off when the gate is at a high level, and the N-type transistor is when the gate is at a low level. It is turned on when the gate is high and turned off when the gate is low.
  • the present application provides a backlight driving circuit and a liquid crystal display device. Each of them will be described in detail below. It should be noted that the description order of the following embodiments is not intended to limit the preferred order of the embodiments.
  • FIG. 1 is a schematic structural diagram of a backlight driving circuit provided by the present application.
  • the present application provides a backlight driving circuit 100 , including a light emitting device 101 , a driving transistor DT, a data signal writing transistor T1 , a storage capacitor C and a light emitting control module 102 .
  • the light-emitting device 101 is connected in series to a light-emitting circuit formed by the first power supply signal VDD and the second power supply signal VSS.
  • the source and drain of the driving transistor DT are connected in series with the light-emitting circuit.
  • the gate of the driving transistor DT is electrically connected to the first node a.
  • the drive transistor DT is used to control the current flowing through the light-emitting circuit.
  • the source of the data signal writing transistor T1 is connected to the data signal D.
  • the drain of the data signal writing transistor T1 is electrically connected to the first node a.
  • the gate of the data signal writing transistor T1 is connected to the scan signal G.
  • the first end of the storage capacitor C is electrically connected to the first node a.
  • the second end of the storage capacitor C is connected to the second power supply signal VSS.
  • the lighting control module 102 is connected to the enable signal En, and is connected to the lighting circuit in series. The lighting control module 102 is used to control the lighting circuit to be turned on or off based on the enable signal En.
  • the present application only needs to ensure that the light-emitting control module 102 and the light-emitting device 101 are connected in series to the light-emitting circuit, and the backlight driving circuit 100 shown in FIG. Location. That is, the light-emitting control module 102 and the light-emitting device 101 can be connected in series at any position on the light-emitting circuit.
  • the driving transistor DT is used to control the current flowing through the light-emitting circuit.
  • the data signal writing transistor T1 is used for writing the data signal D into the first node a under the control of the scan signal G.
  • the lighting control module 102 is used to control the lighting loop to be turned on or off under the control of the enable signal En.
  • the backlight driving circuit 100 used in the present application adds a light-emitting control module 102 on the basis of scanning and lighting the backlight line by line.
  • the light-emitting control module 102 is used to control the light-emitting circuit to be turned on or off under the control of the enable signal En, thereby controlling the light-emitting device 101 to be turned on or off.
  • FIG. 2 is a first circuit schematic diagram of the backlight driving circuit provided by the present application. 1 and 2, the light-emitting control module 102 includes a light-emitting control transistor T2, and the light-emitting device 101 is a light-emitting diode (LED).
  • the source of the light-emitting control transistor T2 is connected to the first power supply signal VDD.
  • the drain of the light-emitting control transistor T2 is electrically connected to the anode of the light-emitting diode LED.
  • the gate of the light-emitting control transistor T2 is connected to the enable signal En.
  • the cathode of the light emitting diode LED is electrically connected to the source of the driving transistor DT.
  • the drain of the driving transistor DT is electrically connected to the second power supply signal VSS.
  • the light-emitting control module 102 can also be formed by using a plurality of transistors in series, and the light-emitting device 101 can also be a mini-LED or a micro-LED.
  • the present application adopts the backlight driving circuit 100 of the 2T1C (two transistors and one storage capacitor) structure to drive the light emitting diode LED to emit light, uses fewer components, has a simple and stable structure, and saves costs.
  • the present application only needs to add one transistor to control the on-off of the light-emitting circuit, so as to realize the BFI, the circuit design is optimized, and the circuit structure is simplified.
  • FIG. 3 is a second circuit schematic diagram of the backlight driving circuit provided by the present application. 1 and 3, the light-emitting control module 102 includes a light-emitting control transistor T2, and the light-emitting device 101 is a light-emitting diode (LED).
  • the source of the light-emitting control transistor T2 is electrically connected to the cathode of the light-emitting diode LED.
  • the drain of the light-emitting control transistor T2 is electrically connected to the drain of the driving transistor DT, and the drain of the driving transistor DT is electrically connected to the second power supply signal VSS.
  • the gate of the light-emitting control transistor T2 is connected to the enable signal En.
  • the anode of the light emitting diode LED is connected to the first power supply signal VDD.
  • the light-emitting control module 102 can also be formed by using a plurality of transistors in series, and the light-emitting device 101 can also be a mini-LED or a micro-LED.
  • FIG. 4 is a third circuit schematic diagram of the backlight driving circuit provided by the present application.
  • the light-emitting control module 102 includes a light-emitting control transistor T2 .
  • the light emitting device 101 is a light emitting diode LED.
  • the source of the light-emitting control transistor T2 is electrically connected to the source of the driving transistor DT.
  • the drain of the light-emitting control transistor T2 is electrically connected to the second node b, and the gate of the light-emitting control transistor T2 is connected to the enable signal En.
  • the anode of the light emitting diode LED is connected to the first power signal VDD, and the cathode of the light emitting diode LED is electrically connected to the drain of the driving transistor DT.
  • the light-emitting control module 102 can also be formed by using a plurality of transistors in series, and the light-emitting device 101 can also be a mini-LED or a micro-LED.
  • the above embodiment is only an example of the position of the lighting control module 102 provided by the present application.
  • the lighting control module 102 of the present application is used to control the on-off of the light-emitting device 101, so it only needs to be connected in series in the lighting circuit.
  • the schematic diagram of the driving circuit is not a limitation of this application.
  • both the first power supply signal VDD and the second power supply signal VSS are used to output a predetermined voltage value.
  • the potential of the first power supply signal VDD is greater than the potential of the second power supply signal VSS.
  • the potential of the second power supply signal VSS may be the potential of the ground terminal.
  • the potential of the second power supply signal can also be other low voltage signals.
  • the data signal writing transistor T1, the light-emitting control transistor T2 and the driving transistor DT are all low temperature polysilicon thin film transistors, oxide semiconductor thin film transistors or amorphous silicon thin film transistors.
  • the transistors in the backlight driving circuit 100 provided by the present application are all of the same type of transistors, so as to avoid the influence of the differences between different types of transistors on the backlight driving circuit 100 .
  • FIG. 5 is a timing diagram of the backlight driving circuit provided by the present application. As shown in FIG. 1 and FIG. 5 , the combination of the scan signal G and the enable signal En sequentially corresponds to the scan phase t1 , the display phase t2 and the black insertion phase t3 .
  • FIG. 6 is a schematic diagram of the path of the backlight driving circuit 100 provided by the present application in the scanning stage t1 under the driving sequence shown in FIG. 5 .
  • the scanning signal G is at a high level, at this time the data signal writing transistor T1 is turned on, the data signal D is transmitted to the first node a, and the storage capacitor C is charged.
  • the potential of the first node a is pulled up to a high potential, the gate-source voltage Vgs of the driving transistor DT is greater than the threshold voltage Vth, and the driving transistor DT is turned on.
  • the enable signal En is at a low level, the light-emitting control transistor T2 is turned off, and the light-emitting circuit is not turned on. Therefore, the light emitting diode LED at this time does not emit light.
  • the gate-source voltage Vgs of the driving transistor DT refers to the potential difference between the first node a and the second node b, that is, the voltage difference between the gate of the driving transistor DT and the source of the driving transistor DT.
  • the scan signal G is at a low level, and the enable signal En is at a high level.
  • FIG. 7 is a schematic diagram of the path of the backlight driving circuit provided by the present application in the display stage t2 under the driving timing shown in FIG. 5 .
  • the scanning signal G is at a low level, at this time the data signal writing transistor T1 is turned off, and the scanning charging has been completed.
  • the potential of the first node a remains at a high level, the gate-source voltage difference Vgs of the driving transistor DT is greater than the threshold voltage Vth, and the driving transistor DT is turned on.
  • the enable signal En is at a high level
  • the light-emitting control transistor T2 is turned on, and the light-emitting circuit is turned on.
  • the light-emitting diode LED is powered by the first power signal VDD, and the current is transmitted to the cathode of the light-emitting diode LED through the anode of the light-emitting diode LED, and the light-emitting diode LED emits light.
  • the scan signal G is at a low level, and the enable signal En is at a low level.
  • FIG. 8 is a schematic diagram of the path of the backlight driving circuit provided by the present application in the black insertion stage t3 under the driving timing shown in FIG. 5 .
  • the scan signal G is low, the data signal writing transistor T1 is turned off, the enable signal En is low, the light-emitting control transistor T2 is turned off, the light-emitting circuit is turned off, and the light-emitting diode LED stops emitting light.
  • the scanning stage t1 and the black insertion stage t3 constitute the whole frame black insertion of the backlight.
  • the time for one scanning phase t1, display phase t2 and black insertion phase t3 is one frame, and the black insertion phase t3 may be in the vertical erasing period, but this is not a limitation of the application .
  • FIG. 9 is a schematic structural diagram of the liquid crystal display device provided by the present application.
  • the liquid crystal display device 1000 includes a backlight module 10 , an array substrate 20 , a color filter substrate 40 , and a liquid crystal layer 30 disposed between the array substrate 20 and the color filter substrate 40 .
  • the backlight module 10 is disposed on the side of the array substrate 20 away from the liquid crystal layer 30 .
  • the backlight module 10 is provided with the backlight driving circuits described in the above embodiments, and the backlight driving circuits are not shown in the figures.
  • the liquid crystal display device 1000 may further include pixel electrodes, common electrodes or other devices. The specific arrangement and assembly of the liquid crystal display device 1000 are technical means well known to those skilled in the art, and will not be repeated here.
  • the liquid crystal display device 1000 provided by the present application adopts a backlight driving circuit, and the backlight driving circuit includes a lighting control module, and the lighting control module is used to control the lighting circuit to be turned on or off under the control of an enable signal, thereby controlling the lighting The device turns on or off.
  • the liquid crystal display device provided by the present application adopts the backlight driving circuit, which can realize the black insertion of the whole frame during the display process, improve the smear phenomenon, improve the product quality, and realize the BFI technology.
  • FIG. 10 is a timing diagram of a driving circuit of the backlight module provided by the present application.
  • the driving timing of the backlight driving circuit includes a scanning phase t1, a display phase t2, and a black insertion phase t3.
  • the scanning stage t1 driven by the pixel electrode and the common electrode, the liquid crystal in the liquid crystal layer 30 is deflected line by line, and the backlight driving circuit performs line-by-line scanning charging under the control of the scanning signal.
  • the backlight module 10 of the liquid crystal display device 1000 includes n rows of backlight units, each row of backlight units is charged row by row under the driving of the corresponding backlight driving circuit, but does not turn on.
  • G1, G2, G3, . . . Gn represent the scanning signals corresponding to the backlight units of the n rows respectively.
  • the deflection of the liquid crystal layer 30 is stable, and the backlight driving circuit drives the backlight module 10 to emit light, so that the liquid crystal display device 1000 displays.
  • the backlight driving circuit simultaneously turns off n rows of backlight units, and the liquid crystal display device does not display at this time.
  • the scan signal G is at a high level
  • the enable signal En is at a low level.
  • the liquid crystal layer 30 is deflected line by line under the control of the pixel electrode and the common electrode, until the voltage between the pixel electrode and the common electrode reaches a preset value, and the liquid crystal deflection in the liquid crystal layer 30 is stable.
  • the scanning signals G1, G2, G3... Bright are the scanning signals G1, G2, G3... Bright.
  • This embodiment is described by taking the backlight driving circuit of the backlight unit of the first row as an example.
  • G1 is at a high level
  • the data signal writing transistor T1 corresponding to the backlight unit of the first row is turned on, the data signal D is transmitted to the first node a, and the Charge the storage capacitor C.
  • the potential of the first node a is pulled up to a high potential
  • the gate-source voltage Vgs of the driving transistor DT is greater than the threshold voltage Vth
  • the driving transistor DT is turned on.
  • the enable signal En since the enable signal En is at a low level, the light-emitting control transistor T2 is turned off, and the light-emitting circuit is not turned on. Therefore, the backlight units of the first row at this time do not emit light.
  • the liquid crystal display device 1000 does not display a screen.
  • the gate-source voltage Vgs of the driving transistor DT refers to the potential difference between the first node a and the second node b, that is, the voltage difference between the gate of the driving transistor DT and the source of the driving transistor DT.
  • the scan signals G1, G2, G3 . . . Gn are all kept at a low level, and the enable signal En is at a high level.
  • the enable signal En is at a high level.
  • the deflection of the liquid crystal layer 30 is completed and the state is stable.
  • the scanning signals G1, G2, G3...Gn are all low level, the data signal writing transistor T1 of the backlight driving circuit in each row of backlight units is turned off, and the scanning charging has been completed.
  • the potential of the first node a remains at a high level, the gate-source voltage difference Vgs of the driving transistor DT is greater than the threshold voltage Vth, and the driving transistor DT is turned on.
  • the enable signal En of the backlight drive circuit in each row of backlight units is at a high level, the light-emitting control transistor T2 is turned on, the light-emitting circuit is turned on, and the current is transmitted through the anode of the light-emitting diode LED to the cathode of the light-emitting diode LED, and the light-emitting diode LED glows.
  • the backlight module 10 is turned on, and the liquid crystal display device 1000 performs screen display.
  • the scan signals G1, G2, G3 . . . Gn are at a low level, and the enable signal En is at a low level.
  • the first power signal VDD no longer supplies power to the light-emitting diode LED, and the light-emitting diode LED stops emitting light.
  • the present application adds a black insertion stage t3, which can release the charge of the storage capacitor C in the backlight driving circuit to achieve the effect of a circuit reset.
  • the backlight can be completely turned off in the black insertion stage t3, so as to avoid that the backlight is not completely turned off in the next frame scanning stage t1, and the liquid crystal will leave afterimages when deflecting, resulting in poor display effect.
  • the circuit can be reset by a potential, so that the scanning charging of the next frame is more accurate, and it is not affected by the residual charge, so as to avoid affecting the luminous brightness of the backlight.
  • the liquid crystal display device 1000 of the present application cyclically reciprocates in the scanning stage, the display stage and the black insertion stage, and finally realizes the function of displaying black insertion frame by frame of the liquid crystal display device 1000, which meets the BFI function requirements and improves the product quality.
  • the liquid crystal display device 1000 of the present application performs backlight display after the deflection of the liquid crystal layer 30 is stable, and the backlight is not turned on when the deflection of the liquid crystal does not reach a stable state. Therefore, the problem of screen smearing when displaying the screen can also be improved.
  • the liquid crystal display device 1000 of the present application can be applied to an active-matrix LED-backlit liquid crystal display, an active-matrix LED-backlit liquid crystal display, or an active-matrix LED-backlit liquid crystal display.
  • the liquid crystal display device 1000 may be an electronic device with a display function, such as a mobile phone, a tablet computer, a notebook, a game console, a digital camera, a car navigation system, an electronic billboard, and an automatic teller machine.
  • a backlight driving circuit and a liquid crystal display device provided by the present application have been introduced in detail above. Specific examples are used to illustrate the principles and implementations of the present application. The descriptions of the above embodiments are only used to help understand the present application. At the same time, for those skilled in the art, according to the idea of the application, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be construed as a Application restrictions.

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Abstract

一种背光驱动电路（100）及液晶显示装置（1000）。背光驱动电路（100）中增加了一个发光控制模块（102），用于控制发光器件（101）的点亮或熄灭，从而控制背光打开或关闭，实现液晶显示装置（1000）背光逐帧插黑，满足BFI功能需求。此外，液晶显示装置（1000）在液晶层（30）偏转稳定之后点亮背光，进行正常画面显示，从而可以改善显示画面拖尾的问题。

Description

一种背光驱动电路及液晶显示装置 技术领域
本申请涉及显示技术领域，具体涉及一种背光驱动电路及液晶显示装置。
 背景技术
液晶显示器（Liquid Crystal Display, LCD）是通过电压控制液晶的翻转角度来控制屏幕显示不同画面的，然而在越来越高刷新率的应用下，在液晶翻转的过程中，若液晶翻转还未到达稳态时背光常亮，人眼就会看到拖尾的问题。
在对现有技术的研究和实践过程中，本申请的发明人发现，一些显示面板的画质评测要求显示器支持整帧插黑（Black Frame Insertion,BFI）的功能，要求背光在液晶面板（open cell, OC）扫描时整帧插黑不显示，待液晶扫描完毕翻转到稳态后再点亮背光。
但主动矩阵式迷你发光二极管（Active Matrix Mini light-emitting diode, AMMini-led）产品的背光是扫描式逐行打开的，无法做到BFI要求的背光整帧插黑，易导致显示画面的拖尾问题。因此，急需解决方案可实现AMMini-led产品整帧插黑。
 技术问题
本申请提供一种背光驱动电路及液晶显示装置，可以实现主动矩阵式液晶显示器的整帧插黑，以提升显示效果，改善显示画面拖尾的问题。
 技术解决方案
本申请提供一种背光驱动电路，包括：
发光器件，所述发光器件串接于第一电源信号与第二电源信号构成的发光回路；
驱动晶体管，所述驱动晶体管的源极以及漏极串接于所述发光回路，所述驱动晶体管的栅极电性连接于第一节点，所述驱动晶体管用于控制流经所述发光回路的电流；
数据信号写入晶体管，所述数据信号写入晶体管的源极接入数据信号，所述数据信号写入晶体管的漏极电性连接于所述第一节点，所述数据信号写入晶体管的栅极接入扫描信号；
存储电容，所述存储电容的第一端电性连接于所述第一节点，所述存储电容的第二端接入所述第二电源信号；
发光控制模块，所述发光控制模块接入发光控制信号，并串接于所述发光回路，所述发光控制模块用于基于所述发光控制信号控制所述发光回路导通或者截止。
可选的，在本申请的一些实施例中，所述发光控制模块包括发光控制晶体管；
所述发光控制晶体管的源极接入所述第一电源信号，所述发光控制晶体管的漏极与所述发光器件电性连接，所述发光控制晶体管的栅极接入所述使能信号。
可选的，在本申请的一些实施例中，所述扫描信号和所述使能信号相组合先后对应于扫描阶段、显示阶段以及插黑阶段。
可选的，在本申请的一些实施例中，在所述扫描阶段，所述扫描信号为高电平，所述使能信号为低电平。
可选的，在本申请的一些实施例中，在所述显示阶段，所述扫描信号为低电平，所述使能信号为高电平。
可选的，在本申请的一些实施例中，在所述插黑阶段，所述扫描信号为低电平，所述使能信号为低电平。
可选的，在本申请的一些实施例中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为低温多晶硅薄膜晶体管。
可选的，在本申请的一些实施例中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为氧化物半导体薄膜晶体管。
可选的，在本申请的一些实施例中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为非晶硅薄膜晶体管。
可选的，在本申请的一些实施例中，所述发光器件为发光二极管，所述发光控制晶体管的漏极与所述发光二极管的阳极电性连接。
相应的，本申请还提供一种液晶显示装置，包括背光模组、阵列基板、彩膜基板以及设置于所述阵列基板和所述彩膜基板之间的液晶层，所述背光模组设置在所述阵列基板远离所述液晶层的一侧，所述背光模组上设置有背光驱动电路，所述背光驱动电路，包括：
发光器件，所述发光器件串接于第一电源信号与第二电源信号构成的发光回路；
驱动晶体管，所述驱动晶体管的源极以及漏极串接于所述发光回路，所述驱动晶体管的栅极电性连接于第一节点，所述驱动晶体管用于控制流经所述发光回路的电流；
数据信号写入晶体管，所述数据信号写入晶体管的源极接入数据信号，所述数据信号写入晶体管的漏极电性连接于所述第一节点，所述数据信号写入晶体管的栅极接入扫描信号；
存储电容，所述存储电容的第一端电性连接于所述第一节点，所述存储电容的第二端接入所述第二电源信号；
发光控制模块，所述发光控制模块接入使能信号，并串接于所述发光回路，所述发光控制模块用于基于所述使能信号控制所述发光回路导通或者截止。
可选的，在本申请的一些实施例中，所述背光驱动电路的驱动时序包括扫描阶段、显示阶段以及插黑阶段，在所述扫描阶段，所述液晶层中的液晶逐行发生偏转，在所述显示阶段，所述液晶层偏转稳定，所述背光驱动电路驱动所述背光模组发光，使所述液晶显示装置进行正常画面显示，在所述插黑阶段，所述背光驱动电路控制所述背光模组关闭。
可选的，在本申请的一些实施例中，在所述扫描阶段，所述扫描信号为高电平，所述使能信号为低电平。
可选的，在本申请的一些实施例中，在所述显示阶段，所述扫描信号为低电平，所述使能信号为高电平。
可选的，在本申请的一些实施例中，在所述插黑阶段，所述扫描信号为低电平，所述使能信号为低电平。
可选的，在本申请的一些实施例中，所述发光控制模块包括发光控制晶体管；
所述发光控制晶体管的源极接入所述第一电源信号，所述发光控制晶体管的漏极与所述发光器件电性连接，所述发光控制晶体管的栅极接入所述使能信号。
可选的，在本申请的一些实施例中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为低温多晶硅薄膜晶体管。
可选的，在本申请的一些实施例中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为氧化物半导体薄膜晶体管。
可选的，在本申请的一些实施例中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为非晶硅薄膜晶体管。
 有益效果
本申请提供一种背光驱动电路及液晶显示装置。本申请在逐行扫描点亮背光的基础上，在背光驱动电路中增加了一个发光控制模块，该发光控制模块可用于控制发光器件的点亮或熄灭，从而实现液晶显示装置背光逐帧插黑，满足BFI功能需求，提升产品品位。
 附图说明
为了更清楚地说明本申请中的技术方案，下面将对实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本申请的一些实施例，对于本领域技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1是本申请提供的背光驱动电路的结构示意图；
图2是本申请提供的背光驱动电路的第一种电路示意图；
图3是本申请提供的背光驱动电路的第二种电路示意图；
图4是本申请提供的背光驱动电路的第三种电路示意图；
图5是本申请提供的背光驱动电路的一种时序图；
图6是本申请提供的背光驱动电路在图5所示的驱动时序下的扫描阶段t1的通路示意图；
图7是本申请提供的背光驱动电路在图5所示的驱动时序下的显示阶段t2的通路示意图；
图8是本申请提供的背光驱动电路在图5所示的驱动时序下的插黑阶段t3的通路示意图；
图9是本申请提供的液晶显示装置的一种结构示意图；
图10是本申请提供的背光模组的一种驱动电路时序图。
 本发明的实施方式
下面将结合本申请中的附图，对本申请中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。此外，应当理解的是，此处所描述的具体实施方式仅用于说明和解释本申请，并不用于限制本申请。在本申请中，在未作相反说明的情况下，使用的方位词如“上”和“下”通常是指装置实际使用或工作状态下的上和下，具体为附图中的图面方向；而“内”和“外”则是针对装置的轮廓而言的。
需要说明的是，由于本申请采用的晶体管的源极、漏极是对称的，所以其源极、漏极是可以互换的。在本申请中，为区分晶体管除栅极之外的两极，将其中一极称为源极，另一极称为漏极。此外本申请所采用的晶体管可以包括P型晶体管和/或N型晶体管两种，其中，P型晶体管在栅极为低电平时导通，在栅极为高电平时截止，N型晶体管为在栅极为高电平时导通，在栅极为低电平时截止。
本申请提供一种背光驱动电路及液晶显示装置。以下分别进行详细说明。需说明的是，以下实施例的描述顺序不作为对实施例优选顺序的限定。
请参阅图1，图1是本申请提供的背光驱动电路的结构示意图。本申请提供了一种背光驱动电路100，包括发光器件101、驱动晶体管DT、数据信号写入晶体管T1、存储电容C以及发光控制模块102。
其中，发光器件101串接于第一电源信号VDD与第二电源信号VSS构成的发光回路。驱动晶体管DT的源极以及漏极串接于发光回路。驱动晶体管DT的栅极电性连接于第一节点a。驱动晶体管DT用于控制流经发光回路的电流。数据信号写入晶体管T1的源极接入数据信号D。数据信号写入晶体管T1的漏极电性连接于第一节点a。数据信号写入晶体管T1的栅极接入扫描信号G。存储电容C的第一端电性连接于第一节点a。存储电容C的第二端接入第二电源信号VSS。发光控制模块102接入使能信号En，并串接于发光回路，发光控制模块102用于基于使能信号En控制发光回路导通或者截止。
需要说明的是，本申请只需保证发光控制模块102以及发光器件101串接于发光回路即可，图1所示的背光驱动电路100仅仅示意出发光控制模块102以及发光器件101的一种具体位置。也即，发光控制模块102以及发光器件101可以串接在发光回路上的任意位置。
具体的，驱动晶体管DT用于控制流经发光回路的电流。数据信号写入晶体管T1用于在扫描信号G的控制下，将数据信号D写入第一节点a。发光控制模块102用于在使能信号En的控制下控制发光回路导通或截止。
本申请采用的背光驱动电路100，在逐行扫描点亮背光的基础上，增加一个发光控制模块102。该发光控制模块102用于在使能信号En的控制下，控制发光回路导通或截止，进而控制发光器件101的点亮或熄灭。采用本申请的背光驱动电路100，可在显示过程中实现整帧插黑，改善拖尾现象，提升产品品位。
请参阅图2，图2是本申请提供的背光驱动电路的第一种电路示意图。结合图1和图2所示，发光控制模块102包括发光控制晶体管T2，发光器件101为发光二极管LED。发光控制晶体管T2的源极接入第一电源信号VDD。发光控制晶体管T2的漏极与发光二极管LED的阳极电性连接。发光控制晶体管T2的栅极接入使能信号En。发光二极管LED的阴极与驱动晶体管DT的源极电性连接。驱动晶体管DT的漏极电性连接于第二电源信号VSS。当然，可以理解地，发光控制模块102还可以采用多个晶体管串联形成，发光器件101还可以为mini-LED或micro-LED。
本申请采用2T1C（2个晶体管以及1个存储电容）结构的背光驱动电路100驱动发光二极管LED发光，用了较少的元器件，结构简单稳定，节约了成本。并且，本申请只需要增加一个晶体管便可控制发光回路的通断，实现BFI的同时，优化了电路设计，简化了电路结构。
请参阅图3，图3是本申请提供的背光驱动电路的第二种电路示意图。结合图1和图3所示，发光控制模块102包括发光控制晶体管T2，发光器件101为发光二极管LED。发光控制晶体管T2的源极与发光二极管LED的阴极电性连接。发光控制晶体管T2的漏极与驱动晶体管DT的漏极电性连接，驱动晶体管DT的漏极电性连接于第二电源信号VSS。发光控制晶体管T2的栅极接入使能信号En。发光二极管LED的阳极接入第一电源信号VDD。当然，可以理解地，发光控制模块102还可以采用多个晶体管串联形成，发光器件101还可以为mini-LED或micro-LED。
请参阅图4，图4是本申请提供的背光驱动电路的第三种电路示意图。结合图1和图4所示，发光控制模块102包括发光控制晶体管T2。发光器件101为发光二极管LED。发光控制晶体管T2的源极与驱动晶体管DT的源极电性连接。发光控制晶体管T2的漏极电性连接于第二节点b，发光控制晶体管T2的栅极接入使能信号En。发光二极管LED的阳极接入第一电源信号VDD，发光二极管LED的阴极与驱动晶体管DT的漏极电性连接。当然，可以理解地，发光控制模块102还可以采用多个晶体管串联形成，发光器件101还可以为mini-LED或micro-LED。
以上实施例仅为对本申请提供的发光控制模块102的位置的示例，实际上本申请的发光控制模块102用于控制发光器件101的通断，因此只需要串接于发光回路中即可，以上的驱动电路示意图不作为对本申请的限制。
在一些实施例中，第一电源信号VDD和第二电源信号VSS均用于输出一预设电压值。此外，在本申请中，第一电源信号VDD的电位大于第二电源信号VSS的电位。具体的，第二电源信号VSS的电位可以为接地端的电位。当然，可以理解地，第二电源信号的电位还可以为其它低电压信号。
在一些实施例中，数据信号写入晶体管T1、发光控制晶体管T2以及驱动晶体管DT均为低温多晶硅薄膜晶体管、氧化物半导体薄膜晶体管或非晶硅薄膜晶体管。本申请提供的背光驱动电路100中的晶体管均为同一种类型的晶体管，从而避免不同类型的晶体管之间的差异性对背光驱动电路100造成的影响。
请参阅图1和图5，图5是本申请提供的背光驱动电路的一种时序图。结合图1和图5所示，扫描信号G和使能信号En相组合先后对应于扫描阶段t1、显示阶段t2以及插黑阶段t3。
在一些实施例中，在扫描阶段t1，扫描信号G为高电平，使能信号En为低电平。具体的，请同时参阅图5和图6，图6是本申请提供的背光驱动电路100在图5所示的驱动时序下的扫描阶段t1的通路示意图。其中，在扫描阶段t1，扫描信号G为高电平，此时数据信号写入晶体管T1打开，数据信号D传输至第一节点a，并向存储电容C充电。此时，第一节点a的电位被拉高至高电位，驱动晶体管DT的栅源电压Vgs大于阈值电压Vth，驱动晶体管DT打开。但是，由于使能信号En为低电平，发光控制晶体管T2关闭，发光回路不导通。因此，此时的发光二极管LED不发光。
其中，驱动晶体管DT的栅源电压Vgs是指第一节点a与第二节点b之间的电位差，也就是驱动晶体管DT的栅极与驱动晶体管DT的源极之间的电压差。
在一些实施例中，在显示阶段t2，扫描信号G为低电平，使能信号En为高电平。具体的，请同时参阅图5和图7，图7是本申请提供的背光驱动电路在图5所示的驱动时序下的显示阶段t2的通路示意图。其中，在显示阶段t2，扫描信号G为低电平，此时数据信号写入晶体管T1关闭，扫描充电已经完成。第一节点a的电位保持为高电平，驱动晶体管DT的栅源电压差Vgs大于阈值电压Vth，驱动晶体管DT打开。此时，使能信号En为高电平，发光控制晶体管T2打开，发光回路导通。发光二极管LED得到第一电源信号VDD供电，则电流通过发光二极管LED的阳极传输至发光二极管LED的阴极，发光二极管LED发光。
在一些实施例中，在插黑阶段t3，扫描信号G为低电平，使能信号En为低电平。具体的，请同时参阅图5和图8，图8是本申请提供的背光驱动电路在图5所示的驱动时序下的插黑阶段t3的通路示意图。其中，在插黑阶段t3，扫描信号G为低电平，数据信号写入晶体管T1关闭，使能信号En为低电平，发光控制晶体管T2关闭，发光回路截止，发光二极管LED停止发光。
需要说明的是，在扫描阶段t1和插黑阶段t3，发光回路均处于截止状态，发光二极管LED不发光。即，扫描阶段t1和插黑阶段t3构成了背光整帧插黑。
需要说明的是，本申请中进行一次扫描阶段t1、显示阶段t2以及插黑阶段t3的时间为一帧，其中插黑阶段t3可以处于垂直消影周期中，但这并不作为对本申请的限制。
本申请提供一种液晶显示装置，请参阅图9，图9是本申请提供的液晶显示装置的一种结构示意图。该液晶显示装置1000包括背光模组10、阵列基板20、彩膜基板40以及设置于阵列基板20和彩膜基板40之间的液晶层30。背光模组10设置在阵列基板20远离液晶层30的一侧。背光模组10上设置有上述各实施例所述的背光驱动电路，图中未示出背光驱动电路。其中，液晶显示装置1000还可以包括像素电极、公共电极或其他装置，液晶显示装置1000的具体设置方式及装配是本领域技术人员所熟知的技术手段，在此不再赘述。
本申请提供的液晶显示装置1000采用一种背光驱动电路，该背光驱动电路包括一个发光控制模块，该发光控制模块用于在使能信号的控制下，控制发光回路导通或截止，进而控制发光器件的点亮或熄灭。本申请提供的液晶显示装置采用了该背光驱动电路，可在显示过程中实现整帧插黑，改善拖尾现象，提升产品品位，实现BFI技术。
请同时参阅图10，图10是本申请提供的背光模组的一种驱动电路时序图，下面结合图9和图10进行说明。在一些实施例中，背光驱动电路的驱动时序包括扫描阶段t1、显示阶段t2以及插黑阶段t3。在扫描阶段t1，在像素电极和公共电极的驱动下，液晶层30中的液晶逐行发生偏转，同时背光驱动电路在扫描信号的控制下进行逐行扫描充电。具体的，液晶显示装置1000的背光模组10包括n行背光单元，每行背光单元在相应的背光驱动电路的驱动下逐行充电，但不启亮。其中，G1、G2、G3……Gn表示n行背光单元分别对应的扫描信号。在显示阶段t2，液晶层30偏转稳定，背光驱动电路驱动背光模组10发光，使液晶显示装置1000显示。在插黑阶段t3，背光驱动电路同时关闭n行背光单元，此时液晶显示装置不显示。
具体的，在一些实施例中，在扫描阶段t1，扫描信号G为高电平，使能信号En为低电平。具体的，请同时参阅图5、图6、图9和图10。在扫描阶段t1，液晶层30在像素电极和公共电极的控制下进行逐行偏转，直至像素电极和公共电极之间的电压到达预设值，液晶层30中的液晶偏转稳定。同时，扫描信号G1、G2、G3……Gn依次由低电平转变为高电平，背光驱动电路在相应扫描信号的控制下控制背光模组10中的背光单元进行逐行充电，但不启亮。
本实施例以第一行背光单元的背光驱动电路为例进行说明，G1为高电平时，第一行背光单元对应的数据信号写入晶体管T1打开，数据信号D传输至第一节点a，并向存储电容C充电。此时，第一节点a的电位被拉高至高电位，驱动晶体管DT的栅源电压Vgs大于阈值电压Vth，驱动晶体管DT打开。但是，由于使能信号En为低电平，发光控制晶体管T2关闭，发光回路不导通。因此，此时的第一行背光单元不发光。
需要说明的是，其他行的背光单元在扫描阶段的工作原理同理，在此不再赘述。因此，在扫描阶段t1，液晶显示装置1000不显示画面。
其中，驱动晶体管DT的栅源电压Vgs是指第一节点a与第二节点b之间的电位差，也就是驱动晶体管DT的栅极与驱动晶体管DT的源极之间的电压差。
具体的，在一些实施例中，在显示阶段t2，扫描信号G1、G2、G3……Gn均保持为低电平，使能信号En为高电平。具体的，请同时参阅图5、图7、图9和图10。在显示阶段t2，液晶层30偏转完成，状态稳定。此时，扫描信号G1、G2、G3……Gn均为低电平，每行背光单元中的背光驱动电路的数据信号写入晶体管T1关闭，扫描充电已经完成。第一节点a的电位保持为高电平，驱动晶体管DT的栅源电压差Vgs大于阈值电压Vth，驱动晶体管DT打开。此时，每行背光单元中的背光驱动电路的使能信号En为高电平，发光控制晶体管T2打开，发光回路导通，电流通过发光二极管LED的阳极传输至发光二极管LED的阴极，发光二极管LED发光。则背光模组10被点亮，液晶显示装置1000进行画面显示。
在一些实施例中，在插黑阶段t3，扫描信号G1、G2、G3……Gn为低电平，使能信号En为低电平。具体的，请同时参阅图5、图8、图9和图10。在插黑阶段t3，扫描信号G1、G2、G3……Gn仍保持为低电平，数据信号写入晶体管T1关闭，使能信号En为低电平，发光控制晶体管T2关闭，发光回路截止，第一电源信号VDD不再向发光二极管LED供电，发光二极管LED停止发光。
本申请加入插黑阶段t3，可以将背光驱动电路中存储电容C的电荷释放掉，达到一个电路复位的效果。一方面，可以在插黑阶段t3使背光完全关闭，避免在下一帧扫描阶段t1时，背光没有完全关闭，使液晶在偏转时留有残影，导致显示效果不佳。另一方面，可以对电路进行一个电位的复位，使下一帧扫描充电更准确，不受到残留电荷的影响，从而避免影响背光的发光亮度。
本申请的液晶显示装置1000在扫描阶段、显示阶段和插黑阶段循环往复，最终实现液晶显示装置1000的显示逐帧插黑的功能，满足BFI功能需求，提升产品品位。另外，本申请的液晶显示装置1000是在液晶层30偏转稳定之后再进行背光显示，在液晶偏转未达到稳态的时候不点亮背光。因此，也可以改善显示画面时画面拖尾的问题。
本申请的液晶显示装置1000可应用于主动矩阵式发光二极管背光液晶显示器、主动矩阵式迷你发光二极管背光液晶显示器或主动矩阵式微型发光二极管背光液晶显示器。该液晶显示装置1000可以为手机、平板电脑、笔记本、游戏机、数码相机、车载导航仪、电子广告牌、自动取款机等具有显示功能的电子设备。
以上对本申请所提供的一种背光驱动电路及液晶显示装置进行了详细介绍，本文中应用了具体个例对本申请的原理及实施方式进行了阐述，以上实施例的说明只是用于帮助理解本申请的方法及其核心思想；同时，对于本领域的技术人员，依据本申请的思想，在具体实施方式及应用范围上均会有改变之处，综上所述，本说明书内容不应理解为对本申请的限制。

Claims (20)

  1. 一种背光驱动电路，其中，包括：
    发光器件，所述发光器件串接于第一电源信号与第二电源信号构成的发光回路；
    驱动晶体管，所述驱动晶体管的源极以及漏极串接于所述发光回路，所述驱动晶体管的栅极电性连接于第一节点，所述驱动晶体管用于控制流经所述发光回路的电流；
    数据信号写入晶体管，所述数据信号写入晶体管的源极接入数据信号，所述数据信号写入晶体管的漏极电性连接于所述第一节点，所述数据信号写入晶体管的栅极接入扫描信号；
    存储电容，所述存储电容的第一端电性连接于所述第一节点，所述存储电容的第二端接入所述第二电源信号；
    发光控制模块，所述发光控制模块接入使能信号，并串接于所述发光回路，所述发光控制模块用于基于所述使能信号控制所述发光回路导通或者截止。
  2. 根据权利要求1所述的背光驱动电路，其中，所述发光控制模块包括发光控制晶体管；
    所述发光控制晶体管的源极接入所述第一电源信号，所述发光控制晶体管的漏极与所述发光器件电性连接，所述发光控制晶体管的栅极接入所述使能信号。
  3. 根据权利要求1所述的背光驱动电路，其中，所述扫描信号和所述使能信号相组合先后对应于扫描阶段、显示阶段以及插黑阶段。
  4. 根据权利要求3所述的背光驱动电路，其中，在所述扫描阶段，所述扫描信号为高电平，所述使能信号为低电平。
  5. 根据权利要求3所述的背光驱动电路，其中，在所述显示阶段，所述扫描信号为低电平，所述使能信号为高电平。
  6. 根据权利要求3所述的背光驱动电路，其中，在所述插黑阶段，所述扫描信号为低电平，所述使能信号为低电平。
  7. 根据权利要求1所述的背光驱动电路，其中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为低温多晶硅薄膜晶体管。
  8. 根据权利要求1所述的背光驱动电路，其中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为氧化物半导体薄膜晶体管。
  9. 根据权利要求1所述的背光驱动电路，其中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为非晶硅薄膜晶体管。
  10. 根据权利要求2所述的背光驱动电路，其中，所述发光器件为发光二极管，所述发光控制晶体管的漏极与所述发光二极管的阳极电性连接。
  11. 一种液晶显示装置，其中，包括背光模组、阵列基板、彩膜基板以及设置于所述阵列基板和所述彩膜基板之间的液晶层，所述背光模组设置在所述阵列基板远离所述液晶层的一侧，所述背光模组上设置有背光驱动电路，所述背光驱动电路，包括：
    发光器件，所述发光器件串接于第一电源信号与第二电源信号构成的发光回路；
    驱动晶体管，所述驱动晶体管的源极以及漏极串接于所述发光回路，所述驱动晶体管的栅极电性连接于第一节点，所述驱动晶体管用于控制流经所述发光回路的电流；
    数据信号写入晶体管，所述数据信号写入晶体管的源极接入数据信号，所述数据信号写入晶体管的漏极电性连接于所述第一节点，所述数据信号写入晶体管的栅极接入扫描信号；
    存储电容，所述存储电容的第一端电性连接于所述第一节点，所述存储电容的第二端接入所述第二电源信号；
    发光控制模块，所述发光控制模块接入使能信号，并串接于所述发光回路，所述发光控制模块用于基于所述使能信号控制所述发光回路导通或者截止。
  12. 根据权利要求11所述的液晶显示装置，其中，所述背光驱动电路的驱动时序包括扫描阶段、显示阶段以及插黑阶段；
    在所述扫描阶段，所述液晶层中的液晶逐行发生偏转，在所述显示阶段，所述液晶层偏转稳定，所述背光驱动电路驱动所述背光模组发光，所述液晶显示装置进行正常画面显示，在所述插黑阶段，所述背光驱动电路控制所述背光模组关闭。
  13. 根据权利要求12所述的液晶显示装置，其中，在所述扫描阶段，所述扫描信号为高电平，所述使能信号为低电平。
  14. 根据权利要求12所述的液晶显示装置，其中，在所述显示阶段，所述扫描信号为低电平，所述使能信号为高电平。
  15. 根据权利要求12所述的液晶显示装置，其中，在所述插黑阶段，所述扫描信号为低电平，所述使能信号为低电平。
  16. 根据权利要求11所述的液晶显示装置，其中，所述发光控制模块包括发光控制晶体管；
    所述发光控制晶体管的源极接入所述第一电源信号，所述发光控制晶体管的漏极与所述发光器件电性连接，所述发光控制晶体管的栅极接入所述使能信号。
  17. 根据权利要求16所述的背光驱动电路，其中，所述发光器件为发光二极管，所述发光控制晶体管的漏极与所述发光二极管的阳极电性连接。
  18. 根据权利要求11所述的液晶显示装置，其中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为低温多晶硅薄膜晶体管。
  19. 根据权利要求11所述的液晶显示装置，其中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为氧化物半导体薄膜晶体管。
  20. 根据权利要求11所述的液晶显示装置，其中，所述数据信号写入晶体管、所述发光控制晶体管、所述驱动晶体管均为非晶硅薄膜晶体管。
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