Driving circuit, backlight module and driving method therefor, and display apparatus

Abstract

The present disclosure provides a driving circuit, a backlight module and a driving method therefor, and a display apparatus. The driving circuit comprises a driving transistor and a voltage adjusting circuit; a source of the driving transistor is coupled to a first voltage signal end, a drain of the driving transistor is coupled to a light-emitting device group, and a gate of the driving transistor is coupled to an output end of the voltage adjusting circuit, wherein the light-emitting device group comprises a plurality of light-emitting regions arranged in a first direction, and each light-emitting region comprises at least one light-emitting device; a first input end of the voltage adjusting circuit is coupled to a second voltage signal end; the voltage of the second voltage signal end is a preset driving voltage Vgs of the driving transistor; the voltage adjusting circuit is used for: in the case that the number of light-emitting regions comprised in the light-emitting device group is not equal to a preset number, outputting a driving voltage Vgs' of the driving transistor according to the input preset driving voltage, the number of the light-emitting regions comprised in the light-emitting device group and the preset number, wherein Vgs' is not equal to Vgs.

Description

Driving circuit, backlight module and driving method thereof, and display device Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a driving circuit, a backlight module and a driving method thereof, and a display device. Background Art

[0002] With the continuous development of display technology, in order to achieve large-size, high-resolution displays, liquid crystal display panels can use mini light-emitting diodes (Mini-LEDs) as the light source of the backlight module. The backlight source includes multiple Mini-LED light-emitting device groups, each Mini-LED light-emitting device group includes multiple partitions, each partition includes at least one Mini-LED, and the multiple Mini-LED light-emitting device groups are driven by different driving circuits, and the driving current corresponding to each light-emitting device group is the same. However, in order to meet the structure and visual range requirements of the display device, the display device usually has a cut corner, and the number of partitions in the Mini-LED light-emitting device group corresponding to the cut corner is less than the number of partitions in the Mini-LED light-emitting device group in the non-cut corner area. When the driving currents corresponding to each Mini-LED light-emitting device group are the same, for a Mini-LED light-emitting device group, the driving current is evenly distributed to multiple partitions in the Mini-LED light-emitting device group. Since the number of partitions in the Mini-LED light-emitting device group corresponding to the cut corner is less than the number of partitions in the Mini-LED light-emitting device group in the non-cut corner area, the current of a partition in the Mini-LED light-emitting device group corresponding to the cut corner is greater than the current of a partition in the Mini-LED light-emitting device group in the non-cut corner area. Therefore, the brightness of the Mini-LED in the Mini-LED light-emitting device group corresponding to the cut corner is greater than the brightness of the Mini-LED in the Mini-LED light-emitting device group in the non-cut corner area, resulting in differences in brightness in different areas of the backlight module, affecting the display effect.

[0003] Summary of the Invention

[0004] An embodiment of the present disclosure provides a driving circuit, the driving circuit comprising: a driving transistor and a voltage regulating circuit;

[0005] The source of the driving transistor is coupled to the first voltage signal terminal, the drain of the driving transistor is used to couple to the light-emitting device group, and the gate of the driving transistor is coupled to the output terminal of the voltage regulation circuit; wherein the light-emitting device group includes a plurality of light-emitting areas arranged along the first direction, and the light-emitting areas include at least one light-emitting device;

[0006] The first input terminal of the voltage regulating circuit is coupled to the second voltage signal terminal; the voltage of the second voltage signal terminal is a preset driving voltage Vgs of the driving transistor; the number of light-emitting areas included in the light-emitting device group is less than, equal to, or greater than a preset number;

[0007] The voltage regulating circuit is used to: when the number of light-emitting areas included in the light-emitting device group is not equal to the preset number, output the driving voltage Vgs' of the driving transistor according to the input preset driving voltage, the number of light-emitting areas included in the light-emitting device group and the preset number; wherein Vgs' is not equal to Vgs.

[0008] In some embodiments, the driving voltage Vgs′ of the driving transistor and the preset driving voltage Vgs satisfy: Wherein, m is the number of light-emitting areas included in the light-emitting device group, n is a preset number, and Vth is the threshold voltage of the driving transistor.

[0009] In some embodiments, the voltage regulating circuit includes: a first operational amplifier, and a second operational amplifier;

[0010] The non-inverting input terminal of the first operational amplifier is coupled to the second voltage signal terminal, the inverting input terminal of the first operational amplifier is coupled to the positive electrode of the fixed voltage source, the inverting input terminal of the second operational amplifier, and the output terminal of the second operational amplifier, and the output terminal of the first operational amplifier is coupled to the inverting input terminal of the second operational amplifier;

[0011] The negative electrode of the fixed voltage source is grounded, and the voltage of the fixed voltage source is the threshold voltage Vth of the driving transistor;

[0012] The gain of the first operational amplifier is

[0013] A non-inverting input terminal of the second operational amplifier is grounded, and an output terminal of the second operational amplifier is coupled to the gate of the driving transistor.

[0014] In some embodiments, the voltage regulating circuit further includes: a first resistor, a second resistor, a third resistor, and a fourth resistor;

[0015] A first end of the first resistor is coupled to the output terminal of the first operational amplifier, and a second end of the first resistor is coupled to the inverting input terminal of the second operational amplifier;

[0016] A first end of the second resistor is coupled to the inverting input terminal of the first operational amplifier, and a second end of the second resistor is coupled to the inverting input terminal of the second operational amplifier;

[0017] A first end of the third resistor is coupled to the output terminal of the second operational amplifier, and a second end of the third resistor is coupled to the inverting input terminal of the second operational amplifier;

[0018] A first end of the fourth resistor is grounded, and a second end of the fourth resistor is coupled to the non-inverting input terminal of the second operational amplifier;

[0019] The resistance values ​​of the first resistor, the second resistor, the third resistor and the fourth resistor are all the same.

[0020] In some embodiments, the voltage regulating circuit further includes: a filter capacitor; a first electrode of the filter capacitor is coupled to the positive electrode of the fixed voltage source and the first end of the second resistor, and a second electrode of the filter capacitor is grounded.

[0021] In some embodiments, the voltage regulation circuit further includes: a first pulse modulation switch; a first end of the first pulse modulation switch is coupled to the second voltage signal end, and a second end of the first pulse modulation switch is coupled to the non-inverting input end of the first operational amplifier.

[0022] In some embodiments, the driving circuit further includes a pulse modulation circuit connected in parallel with the first input terminal and the output terminal of the voltage regulating circuit.

[0023] In some embodiments, the pulse modulation circuit includes: a second pulse modulation switch and a third pulse modulation switch;

[0024] The first end of the second pulse modulation switch is coupled to the second voltage signal end, the second end of the second pulse modulation switch is coupled to the first end of the third pulse modulation switch and the gate of the driving transistor; the second end of the third pulse modulation switch is grounded.

[0025] In some embodiments, the driving circuit further includes: a third operational amplifier and a fourth operational amplifier;

[0026] A non-inverting input terminal of the third operational amplifier is coupled to the second voltage signal terminal, an inverting input terminal of the third operational amplifier is coupled to the source of the driving transistor, and an output terminal of the third operational amplifier is coupled to the non-inverting input terminal of the fourth operational amplifier;

[0027] The inverting input terminal of the fourth operational amplifier is coupled to the output terminal of the fourth operational amplifier, and the output terminal of the fourth operational amplifier is coupled to the first input terminal of the voltage regulating circuit.

[0028] In some embodiments, the driving circuit further includes: an operational amplifier circuit and a fifth resistor; a first input terminal of the operational amplifier circuit is coupled to the second voltage signal terminal, a second input terminal of the operational amplifier circuit is coupled to the current multiplication factor adjustment signal terminal, a third input terminal of the operational amplifier circuit is coupled to the first terminal of the fifth resistor, and an output terminal of the operational amplifier circuit is coupled to the non-inverting input terminal of the third operational amplifier;

[0029] A second terminal of the fifth resistor is grounded.

[0030] In some embodiments, the driving circuit further comprises: a feedback circuit; the feedback circuit comprises a feedback resistor;

[0031] The first end of the feedback resistor is coupled to the source of the driving transistor, and the second end of the feedback resistor is coupled to the first voltage signal end; the first voltage signal end is a ground potential signal end.

[0032] In some embodiments, the driving transistor is an N-type metal-oxide-semiconductor field-effect transistor.

[0033] The embodiment of the present disclosure provides a backlight module, which includes: a plurality of light-emitting device groups and a plurality of first driving circuits; the first driving circuit is the driving circuit provided by the embodiment of the present disclosure;

[0034] The light emitting device group includes a plurality of light emitting areas arranged along a first direction, and the light emitting areas include at least one light emitting device;

[0035] The plurality of light-emitting device groups include a plurality of first light-emitting device groups and a plurality of second light-emitting device groups; the number of light-emitting areas included in the second light-emitting device group is equal to a preset number, and the number of light-emitting areas included in the first light-emitting device group is less than the number of light-emitting areas included in the second light-emitting device group;

[0036] The plurality of first light emitting device groups are respectively coupled to different first driving circuits.

[0037] In some embodiments, the plurality of second light-emitting device groups are respectively coupled to different first driving circuits.

[0038] In some embodiments, the backlight module further includes a plurality of second driving circuits; the plurality of second light-emitting device groups are respectively coupled to different second driving circuits;

[0039] The second driving circuit includes: a driving transistor, a pulse modulation circuit, a voltage stabilization circuit, a feedback circuit, an operational amplifier circuit and a fifth resistor.

[0040] An embodiment of the present disclosure provides a method for driving a backlight module, wherein the method includes:

[0041] controlling a driving circuit coupled to the first light emitting device group to input a preset driving voltage;

[0042] The control voltage regulating circuit outputs a driving voltage of the driving transistor according to the preset driving voltage, the number of light-emitting areas and the preset number to control the driving transistor to be turned on, thereby driving the light-emitting devices in the first light-emitting device group to emit light.

[0043] In some embodiments, the voltage regulating circuit includes a first pulse modulation switch that controls a driving circuit coupled to the first light-emitting device group to input a preset driving voltage, and further includes:

[0044] The first pulse modulation switch is controlled to be closed, and a preset driving voltage is provided to the first input terminal of the voltage regulation circuit through the first pulse modulation switch.

[0045] In some embodiments, the driving circuit further includes a second pulse modulation switch and a third pulse modulation switch, and while controlling the first pulse modulation switch to be closed, further includes:

[0046] The second pulse modulation switch and the third pulse modulation switch are controlled to be turned off.

[0047] In some embodiments, the plurality of second light-emitting device groups are respectively coupled to different driving circuits, and the method further includes:

[0048] The first pulse modulation switch of the driving circuit coupled to the first light emitting device group is controlled to be disconnected, and the second pulse modulation switch is controlled to be closed, so as to control the driving transistor to be turned on and drive the light emitting devices in the second light emitting device group to emit light.

[0049] An embodiment of the present disclosure provides a display device, including:

[0050] The backlight module provided by the embodiment of the present disclosure;

[0051] The display panel is located on the light-emitting side of the backlight module. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0053] FIG1 is a schematic structural diagram of a backlight module provided by an embodiment of the present disclosure;

[0054] FIG2 is a schematic structural diagram of a driving circuit provided by an embodiment of the present disclosure;

[0055] FIG3 is a schematic structural diagram of another driving circuit provided by an embodiment of the present disclosure;

[0056] FIG4 is a schematic structural diagram of another driving circuit provided by an embodiment of the present disclosure;

[0057] FIG5 is a schematic structural diagram of another driving circuit provided by an embodiment of the present disclosure;

[0058] FIG6 is a schematic structural diagram of another driving circuit provided by an embodiment of the present disclosure;

[0059] FIG7 is a schematic structural diagram of another driving circuit provided by an embodiment of the present disclosure;

[0060] FIG8 is a schematic structural diagram of another driving circuit provided by an embodiment of the present disclosure;

[0061] FIG9 is a schematic structural diagram of another driving circuit provided in an embodiment of the present disclosure;

[0062] FIG10 is a schematic structural diagram of another backlight module provided in an embodiment of the present disclosure;

[0063] FIG11 is a schematic structural diagram of another backlight module provided in an embodiment of the present disclosure;

[0064] FIG12 is a schematic structural diagram of another backlight module provided in an embodiment of the present disclosure;

[0065] FIG13 is a schematic flow chart of a method for driving a backlight module according to an embodiment of the present disclosure;

[0066] FIG14 is a schematic structural diagram of a display device provided by an embodiment of the present disclosure;

[0067] FIG15 is a schematic structural diagram of another display device provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0068] In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. And in the absence of conflict, the embodiments in the present disclosure and the features in the embodiments can be combined with each other. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0069] Unless otherwise defined, the technical or scientific terms used in this disclosure should have the usual meanings understood by persons of ordinary skill in the field to which this disclosure belongs. The words "first", "second" and similar terms used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0070] It should be noted that the sizes and shapes of the figures in the accompanying drawings do not reflect the actual scale and are only for the purpose of illustrating the present disclosure. The same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions.

[0071] In the related art, a non-rectangular backlight module is shown in FIG1 , for example, in which the shape of the backlight module 7 is a rectangular shape with cut corners, that is, a shape with the right-angled area of ​​the rectangle cut off. The plurality of light-emitting device groups 4 include a plurality of first light-emitting device groups 8 and a plurality of second light-emitting device groups 9; the first light-emitting device group 8 is located in the area corresponding to the cut corners, and the second light-emitting device group 9 is located in the area outside the cut corners. The number of light-emitting areas 5 in the first light-emitting device group 8 is less than the number of light-emitting areas in the second light-emitting device group 9. The number of light-emitting areas included in the second light-emitting device group 9 is the preset number. That is, due to the existence of the cut corners, the number of light-emitting areas 5 included in the first light-emitting device group 8 located in the area corresponding to the cut corners is less than the preset number. In specific implementation, it is necessary to use a driving transistor to drive the light-emitting device group to emit light, and the driving current of the driving transistor, that is, the total current I of each light-emitting device group, meets the following conditions:

[0072] I=(1 / 2)UnCox(W / L)*(V'-Vth) 2 (1);

[0073] Wherein, Un is the electron migration rate, Cox is the gate oxide capacitance per unit area, W / L is the oxide width-to-length ratio of the driving transistor, V' is the gate voltage of the driving transistor, and Vth is the threshold voltage of the driving transistor. Taking the first light-emitting device group 8 corresponding to the reference numerals in FIG1 as an example, the first light-emitting device group 8 includes four light-emitting areas, while the second light-emitting device group 9 includes eight light-emitting areas. The driving current of each light-emitting area in the first light-emitting device group 8 corresponding to the reference numerals in FIG1 is 1 / 4, while the driving current of each light-emitting area in the second light-emitting device group 9 is 1 / 8. The driving current of each light-emitting area in the first light-emitting device group 8 is greater than the driving current of each light-emitting area in the second light-emitting device group 9. Accordingly, the brightness of each light-emitting area in the first light-emitting device group 8 is higher than the brightness of each light-emitting area in the second light-emitting device group 9. There is a large difference between the brightness of the cut-corner area and the brightness of the non-cut-corner area of ​​the backlight module, which affects the brightness uniformity of the backlight module. When the backlight module is used in a display product, it further affects the display uniformity of the display product.

[0074] The embodiment of the present disclosure provides a driving circuit, as shown in FIG2 , the driving circuit 1 includes: a driving transistor 2 and a voltage regulating circuit 3;

[0075] The source S of the driving transistor 2 is coupled to the first voltage signal terminal V1, the drain g of the driving transistor 2 is used to couple to the light-emitting device group 4, and the gate g of the driving transistor 2 is coupled to the output terminal of the voltage regulation circuit 1. The light-emitting device group 4 includes a plurality of light-emitting regions 5 arranged along a first direction Y, each light-emitting region 5 including at least one light-emitting device 6. The number of light-emitting regions 5 included in the light-emitting device group 4 is less than, equal to, or greater than a predetermined number.

[0076] The first input terminal of the voltage regulating circuit 3 is coupled to the second voltage signal terminal Vref; the voltage of the second voltage signal terminal Vref is the preset driving voltage Vgs of the driving transistor 2;

[0077] The voltage regulating circuit 3 is used to: when the number of light-emitting areas 5 included in the light-emitting device group 4 is not equal to the preset number, output the driving voltage Vgs' of the driving transistor 2 according to the input preset driving voltage, the number of light-emitting areas included in the light-emitting device group 4 and the preset number; wherein Vgs' is not equal to Vgs.

[0078] The driving circuit provided in the embodiments of the present disclosure includes a voltage regulating circuit. The voltage regulating circuit can adjust a preset driving voltage input according to the number of light-emitting areas in the light-emitting device group coupled to the driving circuit and a preset number, so that the driving voltage Vgs' output by the voltage regulating circuit of the driving transistor is not equal to the preset driving voltage Vgs. In this way, the total driving current of the light-emitting device group is not equal to the total driving current corresponding to the preset driving voltage Vgs. Compared with the case where the preset driving voltage Vgs is used to control the driving transistor to turn on to drive the light-emitting device group to emit light, the light-emitting brightness of each light-emitting device in the light-emitting device group can be increased or decreased, thereby avoiding large differences in brightness between different areas of the backlight module and preventing the brightness uniformity of the backlight module from being affected.

[0079] In some embodiments, when the number of light-emitting areas included in the light-emitting device group is less than a preset number, the voltage regulating circuit is used to: output a driving voltage Vgs' of the driving transistor according to the input preset driving voltage, the number of light-emitting areas included in the light-emitting device group, and the preset number; wherein Vgs' <Vgs。

[0080] In the driving circuit provided by the embodiments of the present disclosure, when the number of light-emitting regions included in the light-emitting device group coupled to the driving circuit is less than a preset number, the voltage regulation circuit can regulate the input preset driving voltage based on the number of light-emitting regions in the light-emitting device group coupled to the driving circuit and the preset number, so that the driving voltage Vgs' output by the voltage regulation circuit for the driving transistor is less than the preset driving voltage Vgs. Accordingly, the total driving current of the light-emitting device group is less than the total driving current corresponding to the preset driving voltage Vgs. Compared to the case where the preset driving voltage Vgs is used to control the driving transistor to turn on to drive the light-emitting device group to emit light, the luminance of each light-emitting device in the light-emitting device group can be reduced, thereby avoiding large differences in luminance between different areas of the backlight module and preventing a loss in luminance uniformity of the backlight module.

[0081] Of course, a light-emitting device group in FIG2 may also be a light-emitting device group having a number of light-emitting regions greater than a preset number. When the number of light-emitting regions included in the light-emitting device group is greater than the preset number, in some embodiments, the voltage regulation circuit is configured to output a driving voltage Vgs' of the driving transistor based on an input preset driving voltage, the number of light-emitting regions included in the light-emitting device group, and the preset number; wherein Vgs'>Vgs.

[0082] The driving circuit provided by the embodiment of the present disclosure has the following characteristics: when the number of light-emitting areas included in the light-emitting device group coupled to the driving circuit is greater than a preset number, the total driving current of the light-emitting device group is greater than the total driving current corresponding to the preset driving voltage Vgs. Compared with the case where the preset driving voltage Vgs is used to control the driving transistor to turn on to drive the light-emitting device group to emit light, the luminous brightness of each light-emitting device in the light-emitting device group can be increased, thereby avoiding large differences in brightness between different areas of the backlight module and avoiding affecting the brightness uniformity of the backlight module.

[0083] It should be noted that, for ease of description, the following description will describe a light-emitting device group having a number of light-emitting zones that is not equal to the preset number as a first light-emitting device group, and a light-emitting device group having a number of light-emitting zones that is equal to the preset number as a second light-emitting device group. The second light-emitting device group also needs to be coupled to a driving transistor so that the light-emitting devices in the second light-emitting device group can be controlled to emit light by the driving transistor.

[0084] In a specific implementation, the first light-emitting device group is usually located at the edge of the backlight module, and the number of the first light-emitting device group is usually less than the number of the second light-emitting device group; adjusting the driving voltage of the first light-emitting device group instead of adjusting the driving voltage of the second light-emitting device group can reduce the design and driving difficulty of the backlight module.

[0085] In a specific implementation, the driving voltage of the driving transistor coupled to the second light-emitting device group is the preset driving voltage Vgs. Accordingly, the driving current of the driving transistor coupled to the second light-emitting device group, i.e., the total driving current of the second light-emitting device group, is Id=(1 / 2)UnCox(W / L)*(Vgs-Vth). 2 The number of light-emitting areas included in the second light-emitting device group is n, that is, the preset number is n; therefore, the driving current corresponding to each light-emitting area in the second light-emitting device group is When the driving voltage Vgs' of the driving transistor in the driving circuit provided by the embodiment of the present disclosure is , the driving current of the driving transistor coupled to the first light-emitting device group, i.e., the total driving current of the first light-emitting device group, is Id'=(1 / 2)UnCox(W / L)*(Vgs'-Vth) 2 , the number of light-emitting areas included in the first light-emitting device group is m, so the driving current corresponding to each light-emitting area in the first light-emitting device group is

[0086] In some embodiments, Therefore, the driving current corresponding to each light-emitting area in the first light-emitting device group is equal to the driving current corresponding to each light-emitting area in the second light-emitting device group. The brightness of the light-emitting devices in each light-emitting device group is the same, which can eliminate the brightness difference in different areas of the backlight module and provide the brightness uniformity of the backlight module.

[0087] Specifically, according to It can be deduced that:

[0088]

[0089]

[0090] It can be concluded that the driving voltage Vgs' of the driving transistor and the preset driving voltage Vgs satisfy:

[0091] That is, when the driving voltage of the driving transistor coupled to the second light-emitting device group is the preset driving voltage Vgs and the first light-emitting device group is coupled to the driving circuit provided by the embodiment of the present disclosure, the input preset driving voltage is adjusted by the voltage regulating circuit so that the driving voltage of the driving transistor output by the voltage regulating circuit is Vgs. The brightness of the light emitting devices in the first light emitting device group can be made the same as the brightness of the light emitting devices in the second light emitting device group, which can eliminate the brightness difference in different areas of the backlight module and provide brightness uniformity of the backlight module.

[0092] In some embodiments, as shown in FIG3 , the voltage regulating circuit 3 includes: a first operational amplifier 301 , and a second operational amplifier 302 ;

[0093] The non-inverting input terminal of the first operational amplifier 301 is coupled to the second voltage signal terminal Vref, the inverting input terminal of the first operational amplifier 301 is coupled to the positive electrode of the fixed voltage source V2, the inverting input terminal of the second operational amplifier 302, and the output terminal of the second operational amplifier 302, and the output terminal of the first operational amplifier 301 is coupled to the inverting input terminal of the second operational amplifier 302;

[0094] The negative electrode of the fixed voltage source V2 is grounded, and the voltage of the fixed voltage source V2 is the threshold voltage Vth of the driving transistor;

[0095] The gain of the first operational amplifier 301 is Wherein, m is the number of light-emitting areas, and n is the preset number;

[0096] A non-inverting input terminal of the second operational amplifier 302 is grounded, and an output terminal of the second operational amplifier 302 is coupled to the gate g of the driving transistor 2 .

[0097] In a specific implementation, the gain of the first operational amplifier is determined according to the number of light-emitting areas in the light-emitting device group and the preset number. The non-inverting input terminal of the first operational amplifier is used as the first input terminal of the voltage regulating circuit. The voltage input to the non-inverting input terminal of the first operational amplifier is Vgs, and the voltage input to the inverting input terminal of the first operational amplifier is Vth. Since the gain of the first operational amplifier is Therefore, the voltage output from the output terminal of the first operational amplifier is When the output terminal of the first operational amplifier outputs V301 and the inverting input terminal of the second operational amplifier 302 is also coupled to the positive electrode of the fixed voltage source V2 and the fixed voltage source V2 outputs Vth, V301 and Vth serve as the voltages input to the inverting input terminal of the second operational amplifier 302.

[0098] In some embodiments, as shown in FIG4 , the voltage regulating circuit further includes: a first resistor R1 , a second resistor R2 , a third resistor R3 , and a fourth resistor R4 ;

[0099] A first end of the first resistor R1 is coupled to the output terminal of the first operational amplifier 301 , and a second end of the first resistor R1 is coupled to the inverting input terminal of the second operational amplifier 302 ;

[0100] A first end of the second resistor R2 is coupled to the inverting input terminal of the first operational amplifier 301 , and a second end of the second resistor R2 is coupled to the inverting input terminal of the second operational amplifier 302 ;

[0101] A first end of the third resistor R3 is coupled to the output terminal of the second operational amplifier 302 , and a second end of the third resistor R3 is coupled to the inverting input terminal of the second operational amplifier 302 ;

[0102] A first terminal of the fourth resistor R4 is grounded, and a second terminal of the fourth resistor R4 is coupled to the non-inverting input terminal of the second operational amplifier 302;

[0103] The resistance values ​​of the first resistor R1 , the second resistor R2 , the third resistor R3 and the fourth resistor R4 are all the same.

[0104] In a specific implementation, for the voltage regulation circuit shown in FIG4 , when the output terminal of the first operational amplifier outputs V301, the inverting input terminal of the second operational amplifier 302 is also coupled to the positive electrode of the fixed voltage source V2, and the fixed voltage source V2 outputs Vth, V301 and Vth serve as the inverting input terminal of the second operational amplifier 302. Since the non-inverting input terminal of the second operational amplifier 302 is grounded via a fourth resistor, the virtual short circuit principle shows that the voltage V- at the inverting input terminal of the second operational amplifier 302 = the voltage V at the inverting input terminal of the second operational amplifier 302. +=0. The resistance values ​​of the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4 are all R. According to the virtual circuit principle, the sum of the currents passing through the second resistor R2 and the first resistor R1 is equal to the current passing through the third resistor R3. Therefore, (V301–V-) / R+(Vth–V-) / R=(V302–V-) / R, where V302 is the voltage output by the output terminal of the second operational amplifier 302. Substituting V-=0 into the equation, we can obtain (V301–0) / R+(Vth–0) / R=(V302–0) / R, and thus we can obtain The voltage V302 outputted from the output terminal of the second operational amplifier 302 is the driving voltage Vgs' of the driving transistor. Therefore, by adjusting the preset driving voltage using the voltage regulating circuit provided in the embodiment of the present disclosure, the driving voltage of the driving transistor outputted by the voltage regulating circuit can be adjusted. The brightness of the light-emitting devices in the first light-emitting device group can be made equal to the brightness of the light-emitting devices in the second light-emitting device group, eliminating brightness differences between different areas of the backlight module and improving brightness uniformity of the backlight module. Furthermore, by setting the gain of the first operational amplifier based on the number of light-emitting areas in the light-emitting device group and a preset number, the voltage regulation circuit provided in the embodiments of the present disclosure is used to regulate the driving voltage of the driving transistor, resulting in a simple and precise adjustment method.

[0105] In some embodiments, the first operational amplifier is a programmable operational amplifier.

[0106] It should be noted that when a backlight module includes multiple light-emitting device groups, and the multiple light-emitting device groups include multiple first light-emitting device groups, the multiple first light-emitting device groups need to be coupled to different drive circuits. While the n value of the multiple first light-emitting device groups may be the same, the m values ​​of the multiple first light-emitting device groups may differ. For first light-emitting device groups with different m values, the gains of the first operational amplifiers in the drive circuits coupled to them may also differ. The first operational amplifier in the drive circuit provided in the embodiments of the present disclosure is a programmable operational amplifier, allowing the gain of the first operational amplifier to be specifically set through programming based on the specific values ​​of m and n.

[0107] In some embodiments, the second operational amplifier is a negative feedback operational amplifier.

[0108] In some embodiments, as shown in FIG4 , the voltage regulating circuit 3 further includes a filter capacitor C1 ; a first electrode of the filter capacitor C1 is coupled to the positive electrode of the fixed voltage source V2 and the first end of the second resistor R2 , and a second electrode of the filter capacitor C1 is grounded.

[0109] The driving circuit provided by the embodiment of the present disclosure and the voltage regulation circuit further include a filter capacitor, thereby filtering out the AC signal, making the working performance of the voltage regulation circuit more stable.

[0110] In some embodiments, as shown in Figures 3 and 4, the voltage regulation circuit 1 also includes: a first pulse modulation switch PWM1; the first end of the first pulse modulation switch PWM1 is coupled to the second voltage signal end Vref, and the second end of the first pulse modulation switch PWM1 is coupled to the non-inverting input end of the first operational amplifier 301.

[0111] In a specific implementation, when the voltage regulating circuit is needed to regulate the driving voltage of the driving transistor, the first pulse modulation switch PWM1 is controlled to be closed. When the voltage regulating circuit is not needed to regulate the driving voltage of the driving transistor, the first pulse modulation switch PWM1 is controlled to be open.

[0112] In some embodiments, as shown in FIG5 , the driving circuit further includes a pulse modulation circuit 10 connected in parallel with the first input terminal and the output terminal of the voltage regulating circuit 3 .

[0113] In some embodiments, as shown in FIG5 , the pulse modulation circuit 10 includes: a second pulse modulation switch PWM2 and a third pulse modulation switch PWM3 ;

[0114] The first end of the second pulse modulation switch PWM2 is coupled to the second voltage signal end Vref, the second end of the second pulse modulation switch PWM2 is coupled to the first end of the third pulse modulation switch PWM3 and the gate g of the driving transistor 2; the second end of the third pulse modulation switch PWM3 is grounded.

[0115] In a specific implementation, when the voltage regulation circuit is required to regulate the driving voltage of the driving transistor, the first pulse modulation switch PWM1 is controlled to be closed and the second pulse modulation switch PWM2 is controlled to be opened. When the voltage regulation circuit is not required to regulate the driving voltage of the driving transistor, the first pulse modulation switch PWM1 is controlled to be opened. In this case, the light-emitting devices in the light-emitting device group can be controlled to be unlit by controlling both the second pulse modulation switch PWM2 and the third pulse modulation switch PWM3 to be closed, or the second pulse modulation switch PWM2 can be controlled to be closed and the third pulse modulation switch PWM3 to be opened so that the driving voltage is provided to the driving transistor via the second pulse modulation switch PWM2.

[0116] It should be noted that, in order to facilitate the production of the backlight module, the second light-emitting device group can also be coupled to the driving circuit provided in the embodiment of the present disclosure. However, since the number of light-emitting areas in the second light-emitting device group has not been reduced, there is no need to adjust the driving voltage of the driving transistor through the voltage regulation circuit. In this case, the first pulse modulation switch PWM1 can be controlled to be disconnected, and the second pulse modulation switch PWM2 can be controlled to be closed while the third pulse modulation switch PWM3 is disconnected to provide a driving voltage to the driving transistor through the second pulse modulation switch PWM2 to drive the light-emitting devices in the second light-emitting device group to emit light.

[0117] In some embodiments, as shown in FIG6 , the driving circuit further includes: a voltage stabilizing circuit 11 ; the voltage stabilizing circuit 11 includes: a third operational amplifier 1102 and a fourth operational amplifier 1101 ;

[0118] A non-inverting input terminal of the third operational amplifier 1102 is coupled to the second voltage signal terminal Vref, an inverting input terminal of the third operational amplifier 1102 is coupled to the source s of the driving transistor 2, and an output terminal of the third operational amplifier 1102 is coupled to a non-inverting input terminal of the fourth operational amplifier 1101;

[0119] An inverting input terminal of the fourth operational amplifier 1101 is coupled to an output terminal of the fourth operational amplifier 1101 , and the output terminal of the fourth operational amplifier 1101 is coupled to a first input terminal of the voltage regulating circuit 3 .

[0120] In a specific implementation, as shown in FIG6 , when the voltage regulation circuit 3 includes the first pulse modulation switch PWM1, the output terminal of the fourth operational amplifier 1101 is coupled to the non-inverting input terminal of the first operational amplifier 301 via the first pulse modulation switch PWM1. When the drive circuit 1 further includes the pulse modulation circuit 10, the output terminal of the fourth operational amplifier 1101 is also coupled to the first terminal of the second pulse modulation switch PWM2.

[0121] In some embodiments, as shown in FIG7 , the driving circuit further includes: an operational amplifier circuit and a fifth resistor R5; a first input terminal of the operational amplifier circuit is coupled to the second voltage signal terminal Vref, a second input terminal of the operational amplifier circuit is coupled to the current multiplication factor adjustment signal terminal ISET, a third input terminal of the operational amplifier circuit is coupled to the first terminal of the fifth resistor R5, and an output terminal of the operational amplifier circuit is coupled to the non-inverting input terminal of the third operational amplifier 1102;

[0122] A second terminal of the fifth resistor R5 is grounded.

[0123] In a specific implementation, a reference voltage is input to the first input terminal of the operational amplifier circuit, and the operational amplifier circuit adjusts the current multiplication factor of the reference voltage under the control of the current multiplication factor adjustment signal of the current multiplication factor adjustment signal terminal ISET, and outputs the reference voltage after the current multiplication factor adjustment.

[0124] In some embodiments, as shown in FIG8 , the driving circuit further includes: a feedback circuit 12 ; the feedback circuit includes a feedback resistor R6 ;

[0125] A first terminal of the feedback resistor R6 is coupled to the source s of the driving transistor 2 , and a second terminal of the feedback resistor R6 is coupled to the first voltage signal terminal V1 ; the first voltage signal terminal V1 is a ground potential signal terminal.

[0126] In some embodiments, as shown in FIG9 , the feedback circuit 12 further includes a digital-to-analog converter DAC located between the feedback resistor R6 and the ground potential signal terminal.

[0127] In some embodiments, the driving transistor is a metal-oxide-semiconductor field-effect transistor. For example, as shown in Figures 2 to 9, the driving transistor 2 is an N-type metal-oxide-semiconductor field-effect transistor. Of course, in a specific implementation, the driving transistor can also be a P-type metal-oxide-semiconductor field-effect transistor.

[0128] Based on the same inventive concept, the embodiment of the present disclosure further provides a backlight module, as shown in FIG1 and FIG10 , the backlight module includes: a plurality of light-emitting device groups 4, and a plurality of first drive circuits; the first drive circuit is the drive circuit 1 provided in the embodiment of the present disclosure;

[0129] The light emitting device group 4 includes a plurality of light emitting areas 5 arranged along a first direction Y, and the light emitting area 5 includes at least one light emitting device 6;

[0130] The plurality of light-emitting device groups 4 include a plurality of first light-emitting device groups 8 and a plurality of second light-emitting device groups 9; the number of light-emitting areas 5 included in the second light-emitting device group 9 is equal to a preset number, and the number of light-emitting areas 5 included in the first light-emitting device group 8 is not equal to the number of light-emitting areas 5 included in the second light-emitting device group 9;

[0131] The plurality of first light emitting device groups 8 are respectively coupled to different driving circuits 1 (ie, first driving circuits).

[0132] The first driving circuit provided in the backlight module according to the embodiment of the present disclosure is the aforementioned driving circuit provided in the embodiment of the present disclosure. Since the first driving circuit includes a voltage regulating circuit, the voltage regulating circuit can adjust the input preset driving voltage according to the number of light-emitting zones in the light-emitting device group coupled to the first driving circuit and the preset number, so that the driving voltage Vgs' output by the voltage regulating circuit of the driving transistor is not equal to the preset driving voltage Vgs. When the first light-emitting device group is coupled to the first driving circuit, the total driving current of the first light-emitting device group is not equal to the total driving current corresponding to the preset driving voltage Vgs. Compared with the case where the preset driving voltage Vgs is used to control the driving transistor to turn on to drive the first light-emitting device group to emit light, the luminance of each light-emitting device in the first light-emitting device group can be increased or decreased, thereby avoiding a large difference in luminance between the light-emitting devices in the first light-emitting device group and the second light-emitting device group, thereby avoiding affecting the luminance uniformity of the backlight module.

[0133] It should be noted that FIG1 illustrates an example in which the number of light-emitting regions 5 included in the first light-emitting device group 8 is less than the number of light-emitting regions 5 included in the second light-emitting device group 9. When the first light-emitting device group is coupled to the first drive circuit, the voltage regulation circuit can adjust the input preset driving voltage based on the number of light-emitting regions in the light-emitting device group coupled to the first drive circuit and the preset number, so that the voltage regulation circuit outputs a driving voltage Vgs' of the driving transistor less than the preset driving voltage Vgs. Accordingly, the total driving current of the first light-emitting device group is less than the total driving current corresponding to the preset driving voltage Vgs. Compared to the case where the preset driving voltage Vgs is used to control the driving transistor to turn on to drive the first light-emitting device group to emit light, the brightness of each light-emitting device in the first light-emitting device group can be reduced, thereby avoiding a large difference in brightness between the light-emitting devices in the first light-emitting device group and the second light-emitting device group, and thus preventing an impact on the brightness uniformity of the backlight module.

[0134] Of course, in a specific implementation, the number of light-emitting areas included in the first light-emitting device group may be greater than the number of light-emitting areas included in the second light-emitting device group. When the first light-emitting device group is coupled to the first drive circuit, the voltage regulation circuit may adjust the input preset driving voltage according to the number of light-emitting areas in the light-emitting device group coupled to the first drive circuit and the preset number, so that the voltage regulation circuit outputs a driving voltage Vgs' of the driving transistor greater than the preset driving voltage Vgs. Accordingly, the total driving current of the first light-emitting device group is greater than the total driving current corresponding to the preset driving voltage Vgs. Compared to the case where the preset driving voltage Vgs is used to control the driving transistor to turn on to drive the first light-emitting device group to emit light, the luminance of each light-emitting device in the first light-emitting device group can be increased, thereby avoiding a large difference in the luminance of the light-emitting devices in the first light-emitting device group and the second light-emitting device group, and avoiding affecting the brightness uniformity of the backlight module.

[0135] In a specific implementation, as shown in FIG1 , the shape of the backlight module 7 is a rectangular shape with cut corners, that is, a shape with the right-angled area of ​​the rectangle cut off. In a specific implementation, when the backlight module is applied to a virtual reality (VR) display, for example, when applied to VR glasses, the VR glasses include two display screens, each of which includes the backlight module provided by the embodiment of the present disclosure. The shape of the backlight module corresponds to the shape of the display screen, that is, the entire display screen is also a rectangular shape with cut corners, which can reduce the pupil distance between the two display screens. In addition, for VR glasses, when the user uses the glasses, the human eye is very close to the display screen and will not notice the boundary of the display screen. Therefore, the cut corners do not affect the viewing angle and can also reduce the weight of the VR glasses.

[0136] It should be noted that FIG1 does not show all light-emitting device groups. FIG1 illustrates an example in which the second light-emitting device group includes eight light-emitting zones, i.e., the preset number of light-emitting zones is eight, and the first light-emitting device group includes four or six light-emitting zones. Of course, the number of light-emitting device groups, the preset number of light-emitting zones, and the number of light-emitting zones in multiple first light-emitting device groups can be set based on the actual size and shape of the backlight module.

[0137] It should be noted that the second light-emitting device group is not shown in Figure 10. Furthermore, Figure 10 illustrates an example in which the first driving circuit includes a voltage regulation circuit and a driving transistor. In a specific implementation, the first driving circuit may further include a pulse modulation circuit, a voltage stabilization circuit, a feedback circuit, an operational amplifier circuit, and a fifth resistor.

[0138] In some embodiments, as shown in FIG11 , when the driving circuit 1 (ie, the first driving circuit) includes an operational amplifier circuit and a fifth resistor R5 , multiple driving circuits 1 (ie, the first driving circuits) can share the operational amplifier circuit and the fifth resistor R5 .

[0139] In some embodiments, as shown in FIG11 , a plurality of second light-emitting device groups 9 are respectively coupled to different driving circuits 1 (ie, first driving circuits).

[0140] That is, in the backlight module provided by the embodiment of the present disclosure, each light emitting device group is coupled to the above-mentioned driving circuit provided by the embodiment of the present disclosure in a one-to-one correspondence, thereby simplifying the design and manufacturing difficulty of the backlight module driving circuit.

[0141] Of course, in a specific implementation, the driving circuits connected to the multiple second light-emitting device groups may not be coupled to the driving circuits provided in the embodiments of the present disclosure. In some embodiments, as shown in FIG12 , the backlight module further includes multiple second driving circuits 33. Among the multiple light-emitting device groups, only the first light-emitting device group is coupled to the first driving circuit, while the second light-emitting device group is coupled to the second driving circuit. As shown in FIG12 , the second driving circuit 33, for example, includes: a driving transistor 2, a pulse modulation circuit 10, a voltage stabilizing circuit 11, a feedback circuit 12, an operational amplifier circuit, and a fifth resistor R5. The connection relationship between the driving transistor, the pulse modulation circuit, the voltage stabilizing circuit, the feedback circuit, the operational amplifier circuit, and the fifth resistor included in the second driving circuit is the same as the connection relationship of the above-mentioned circuits in the first driving circuit. The specific composition of the pulse modulation circuit, the voltage stabilizing circuit, the feedback circuit, and the operational amplifier circuit included in the second driving circuit is the same as the specific composition of the above-mentioned circuits in the first driving circuit, and will not be repeated here. As shown in FIG12 , when the driving circuit 1 (i.e., the first driving circuit) and the second driving circuit 33 both include an operational amplifier circuit and a fifth resistor R5, multiple driving circuits 1 (i.e., the first driving circuit) and multiple second driving circuits 33 can share the operational amplifier circuit and the fifth resistor R5.

[0142] In a specific implementation, as shown in Figures 10 and 11, the drain of the driving transistor is coupled to the cathode of the light-emitting device, and the anode of the light-emitting device is coupled to the anode voltage signal terminal PVDD, which provides an anode voltage signal to the anode of the light-emitting device. In a specific implementation, the light-emitting areas 5 are arranged in an array along a first direction Y and a second direction X, with the first direction Y intersecting the second direction X. Figures 10 and 11 illustrate this by taking the first direction Y and the second direction X as an example. The anodes of the light-emitting devices in a row of light-emitting areas 5 arranged along the second direction X are coupled to the same anode signal line 18. Specifically, the anode signal line can also be coupled to the anode voltage signal terminal PVDD via a data selector (MUX). This MUX controls whether the anode voltage signal is input to each light-emitting area in a row. The number of MUXs is the same as the number of pre-set light-emitting areas. Figures 10 and 11 illustrate this by taking the example of each light-emitting area 5 including one light-emitting device 6. In a specific implementation, each light-emitting area can also include multiple light-emitting devices arranged along the first direction Y.

[0143] In practice, the backlight module provided by the embodiments of the present disclosure can be driven to achieve two lighting modes: a constant-on mode and a blackout mode. In the constant-on mode, the light-emitting devices in each light-emitting device group are constantly on. In the blackout mode, timing control is employed. For example, in a row of light-emitting areas coupled to a MUX, only one MUX is turned on at a time, and the light-emitting devices in the corresponding row of light-emitting areas are illuminated. This cycle repeats, utilizing the human persistence of vision to display the entire backlight, thus achieving low-power display.

[0144] In some embodiments, the light emitting device is a micro-sized inorganic light emitting diode, which may be, for example, a mini light emitting diode (Mini Light Emitting Diode, Mini-LED) or a micro light emitting diode (Micro Light Emitting Diode, Micro-LED).

[0145] An embodiment of the present disclosure provides a method for driving a backlight module, as shown in FIG13 , including:

[0146] S101, controlling a driving circuit coupled to a first light-emitting device group to input a preset driving voltage;

[0147] S102 , the control voltage regulating circuit outputs a driving voltage of the driving transistor according to the preset driving voltage, the number of light-emitting areas and the preset number, controls the driving transistor to be turned on, and drives the light-emitting devices in the first light-emitting device group to emit light.

[0148] The embodiment of the present disclosure provides a driving method for a backlight module, which uses a voltage regulation circuit to regulate the input preset driving voltage according to the number of light-emitting areas in the first light-emitting device group and a preset number, so that the driving voltage Vgs' output by the voltage regulation circuit of the driving transistor is not equal to the preset driving voltage Vgs, and the total driving current of the first light-emitting device group is not equal to the total driving current corresponding to the preset driving voltage Vgs. Compared with the case of using the preset driving voltage Vgs to control the driving transistor to turn on to drive the first light-emitting device group to emit light, the luminous brightness of each light-emitting device in the first light-emitting device group can be increased or decreased, thereby avoiding a large difference in the brightness of the light-emitting devices in the first light-emitting device group and the second light-emitting device group, and avoiding affecting the brightness uniformity of the backlight module.

[0149] In some embodiments, the voltage regulating circuit includes a first pulse modulation switch that controls a driving circuit coupled to the first light-emitting device group to input a preset driving voltage, and further includes:

[0150] The first pulse modulation switch is controlled to be closed, and a preset driving voltage is provided to the first input terminal of the voltage regulation circuit through the first pulse modulation switch.

[0151] In some embodiments, the driving circuit further includes a second pulse modulation switch and a third pulse modulation switch, and while controlling the first pulse modulation switch to be closed, further includes:

[0152] The second pulse modulation switch and the third pulse modulation switch are controlled to be turned off.

[0153] In some embodiments, the plurality of second light-emitting device groups are respectively coupled to different driving circuits, further comprising:

[0154] The first pulse modulation switch of the driving circuit coupled to the first light emitting device group is controlled to be disconnected, and the second pulse modulation switch is controlled to be closed, so as to control the driving transistor to be turned on and drive the light emitting devices in the second light emitting device group to emit light.

[0155] In some embodiments, it further includes:

[0156] The first pulse modulation switch is controlled to be opened, and the second pulse modulation switch and the third pulse modulation switch are controlled to be closed.

[0157] In some embodiments, while controlling the driving transistor to be turned on to drive the light-emitting devices in the first light-emitting device group to emit light, or while controlling the driving transistor to be turned on to drive the light-emitting devices in the second light-emitting device group to emit light, the method further includes:

[0158] An anode voltage signal is provided to the anode of the light emitting device through the anode voltage signal terminal.

[0159] Based on the same inventive concept, an embodiment of the present disclosure further provides a display device, as shown in FIG14 , comprising:

[0160] The backlight module 13 provided in the embodiment of the present disclosure;

[0161] The display panel 14 is located on the light-emitting side of the backlight module 13 .

[0162] In some embodiments, the display panel is a liquid crystal display panel. As shown in FIG15 , the liquid crystal display panel includes an array substrate 15 and an opposite substrate 16 that are oppositely arranged, and a liquid crystal layer 17 located between the array substrate 15 and the opposite substrate 16 .

[0163] In some embodiments, as shown in FIG15 , the array substrate 15 includes a first base substrate 20, a buffer layer 21 disposed on the side of the first base substrate 20 facing the liquid crystal layer 17, an active layer 19 of the thin-film transistor (TFT), a gate insulating layer 22, a gate electrode G of the thin-film transistor (TFT), an interlayer insulating layer 23, a source electrode S and a drain electrode D of the thin-film transistor (TFT), a planarization layer 24, a common electrode 25, a passivation layer 26, a pixel electrode 27, and a protective layer 28. The counter substrate 16 includes a second base substrate 29, a color resist 30 located on the side of the second base substrate 29 facing the liquid crystal layer 17, and a black matrix 31. The black matrix 31 includes a plurality of openings 32, and the color resist 30 is located within the openings 32.

[0164] The display device provided in the embodiments of the present disclosure is any product or component with a display function, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or navigation system. Other essential components of the display device are well understood by those skilled in the art and are not described here in detail, nor should they be construed as limitations of the present disclosure. The implementation of the display device can be referenced to the aforementioned embodiments of the drive circuit and backlight module, and any repetitive details will not be repeated.

[0165] In summary, the embodiments of the present disclosure provide a driving circuit, a backlight module, a driving method thereof, and a display device. The driving circuit includes a voltage regulation circuit. The voltage regulation circuit can adjust a preset driving voltage input based on the number of light-emitting areas in the light-emitting device group coupled to the driving circuit and a preset number, so that the driving voltage Vgs' output by the voltage regulation circuit for the driving transistor is not equal to the preset driving voltage Vgs. Accordingly, the total driving current of the light-emitting device group is not equal to the total driving current corresponding to the preset driving voltage Vgs. Compared to the case where the preset driving voltage Vgs is used to control the driving transistor to turn on to drive the light-emitting device group to emit light, the luminance of each light-emitting device in the light-emitting device group can be increased or decreased, thereby avoiding large differences in brightness between different areas of the backlight module and preventing the brightness uniformity of the backlight module from being affected.

[0166] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0167] Obviously, those skilled in the art may make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, if such changes and modifications of the embodiments of the present invention fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A driving circuit, wherein: The driving circuit includes: a driving transistor and a voltage regulating circuit; The source of the driving transistor is coupled to the first voltage signal terminal, the drain of the driving transistor is used to couple to the light-emitting device group, and the gate of the driving transistor is coupled to the output terminal of the voltage regulation circuit; wherein the light-emitting device group includes a plurality of light-emitting areas arranged along a first direction, each light-emitting area including at least one light-emitting device; the number of the light-emitting areas included in the light-emitting device group is less than, equal to, or greater than a preset number; The first input terminal of the voltage regulating circuit is coupled to the second voltage signal terminal; the voltage of the second voltage signal terminal is the preset driving voltage Vgs of the driving transistor; The voltage regulating circuit is used to: when the number of the light-emitting areas included in the light-emitting device group is not equal to the preset number, output the driving voltage Vgs' of the driving transistor according to the input preset driving voltage, the number of the light-emitting areas included in the light-emitting device group and the preset number; wherein Vgs' is not equal to Vgs.

2. The driving circuit according to claim 1, wherein: The driving voltage Vgs′ of the driving transistor and the preset driving voltage Vgs satisfy: Wherein, m is the number of the light-emitting areas included in the light-emitting device group, n is the preset number, and Vth is the threshold voltage of the driving transistor.

3. The driving circuit according to claim 2, wherein: The voltage regulating circuit includes: a first operational amplifier and a second operational amplifier; The non-inverting input terminal of the first operational amplifier is coupled to the second voltage signal terminal, the inverting input terminal of the first operational amplifier is coupled to the positive electrode of the fixed voltage source, the inverting input terminal of the second operational amplifier, and the output terminal of the second operational amplifier, and the output terminal of the first operational amplifier is coupled to the inverting input terminal of the second operational amplifier; The negative electrode of the fixed voltage source is grounded, and the voltage of the fixed voltage source is the threshold voltage Vth of the driving transistor; The gain of the first operational amplifier is A non-inverting input terminal of the second operational amplifier is grounded, and an output terminal of the second operational amplifier is coupled to the gate of the driving transistor.

4. The driving circuit according to claim 3, wherein: The voltage regulating circuit further includes: a first resistor, a second resistor, a third resistor and a fourth resistor; A first end of the first resistor is coupled to the output end of the first operational amplifier, and a second end of the first resistor is coupled to the inverting input end of the second operational amplifier; A first end of the second resistor is coupled to the inverting input terminal of the first operational amplifier, and a second end of the second resistor is coupled to the inverting input terminal of the second operational amplifier; A first end of the third resistor is coupled to the output end of the second operational amplifier, and a second end of the third resistor is coupled to the inverting input end of the second operational amplifier; A first end of the fourth resistor is grounded, and a second end of the fourth resistor is coupled to the non-inverting input terminal of the second operational amplifier; The resistance values ​​of the first resistor, the second resistor, the third resistor, and the fourth resistor are all the same.

5. The driving circuit according to claim 4, wherein: The voltage regulating circuit further includes: a filter capacitor; a first electrode of the filter capacitor is coupled to the positive electrode of the fixed voltage source and the first end of the second resistor, and a second electrode of the filter capacitor is grounded.

6. The driving circuit according to any one of claims 3 to 5, wherein: The voltage regulation circuit further includes: a first pulse modulation switch; a first end of the first pulse modulation switch is coupled to the second voltage signal end, and a second end of the first pulse modulation switch is coupled to the non-inverting input end of the first operational amplifier.

7. The driving circuit according to any one of claims 1 to 6, wherein: The driving circuit further includes a pulse modulation circuit connected in parallel with the first input terminal and the output terminal of the voltage regulating circuit.

8. The driving circuit according to claim 7, wherein: The pulse modulation circuit includes: a second pulse modulation switch and a third pulse modulation switch; The first end of the second pulse modulation switch is coupled to the second voltage signal end, the second end of the second pulse modulation switch is coupled to the first end of the third pulse modulation switch and the gate of the driving transistor; the second end of the third pulse modulation switch is grounded.

9. The driving circuit according to claim 7 or 8, wherein: The driving circuit further includes: a voltage stabilizing circuit; the voltage stabilizing circuit includes: a third operational amplifier and a fourth operational amplifier; The non-inverting input terminal of the third operational amplifier is coupled to the second voltage signal terminal, the inverting input terminal of the third operational amplifier is coupled to the source of the driving transistor, and the output terminal of the third operational amplifier is coupled to the non-inverting input terminal of the fourth operational amplifier; The inverting input terminal of the fourth operational amplifier is coupled to the output terminal of the fourth operational amplifier, and the output terminal of the fourth operational amplifier is coupled to the first input terminal of the voltage regulating circuit.

10. The driving circuit according to claim 9, wherein: The driving circuit further includes: an operational amplifier circuit and a fifth resistor; a first input terminal of the operational amplifier circuit is coupled to the second voltage signal terminal, a second input terminal of the operational amplifier circuit is coupled to the current multiplication factor adjustment signal terminal, a third input terminal of the operational amplifier circuit is coupled to the first terminal of the fifth resistor, and an output terminal of the operational amplifier circuit is coupled to the non-inverting input terminal of the third operational amplifier; A second end of the fifth resistor is grounded.

11. The driving circuit according to any one of claims 1 to 10, wherein: The driving circuit further includes: a feedback circuit; the feedback circuit includes a feedback resistor; The first end of the feedback resistor is coupled to the source of the driving transistor, and the second end of the feedback resistor is coupled to the first voltage signal end; the first voltage signal end is a ground potential signal end.

12. The driving circuit according to any one of claims 1 to 11, wherein: The driving transistor is an N-type metal-oxide-semiconductor field-effect transistor.

13. A backlight module, wherein: The backlight module comprises: a plurality of light emitting device groups and a plurality of first driving circuits; the first driving circuit is a driving circuit according to any one of claims 1 to 12; The light emitting device group includes a plurality of light emitting areas arranged along a first direction, and the light emitting area includes at least one light emitting device; The plurality of light-emitting device groups include a plurality of first light-emitting device groups and a plurality of second light-emitting device groups; the number of the light-emitting areas included in the second light-emitting device group is equal to a preset number, and the number of the light-emitting areas included in the first light-emitting device group is less than the number of the light-emitting areas included in the second light-emitting device group; The plurality of first light emitting device groups are respectively coupled to different first driving circuits.

14. The backlight module according to claim 13, wherein: The plurality of second light emitting device groups are respectively coupled to different first driving circuits.

15. The backlight module according to claim 13, wherein: The backlight module further includes a plurality of second driving circuits; the plurality of second light emitting device groups are respectively coupled to different second driving circuits; The second driving circuit includes: a driving transistor, a pulse modulation circuit, a voltage stabilization circuit, a feedback circuit, an operational amplifier circuit and a fifth resistor.

16. A method for driving a backlight module according to any one of claims 13 to 15, wherein: The method comprises: controlling the driving circuit coupled to the first light-emitting device group to input a preset driving voltage; The voltage regulating circuit is controlled to output the driving voltage of the driving transistor according to the preset driving voltage, the number of the light-emitting areas and the preset number to control the driving transistor to be turned on, thereby driving the light-emitting devices in the first light-emitting device group to emit light.

17. The method according to claim 16, wherein The voltage regulating circuit includes a first pulse modulation switch, which controls the driving circuit coupled to the first light-emitting device group to input a preset driving voltage, and further includes: The first pulse modulation switch is controlled to be closed, and the preset driving voltage is provided to the first input terminal of the voltage regulating circuit through the first pulse modulation switch.

18. The method according to claim 17, wherein The driving circuit further includes a second pulse modulation switch and a third pulse modulation switch, and while controlling the first pulse modulation switch to be closed, the driving circuit further includes: The second pulse modulation switch and the third pulse modulation switch are controlled to be turned off.

19. The method according to claim 18, wherein The plurality of second light-emitting device groups are respectively coupled to different driving circuits, and the method further includes: The first pulse modulation switch of the driving circuit coupled to the first light emitting device group is controlled to be disconnected, and the second pulse modulation switch is controlled to be closed, and the driving transistor is controlled to be turned on to drive the light emitting devices in the second light emitting device group to emit light.

20. A display device, wherein: include: The backlight module according to claim 14 or 15; The display panel is located on the light-emitting side of the backlight module.