Mini LED backlight channel light bar control circuit and display device
Through multiple switch units, the sequential lighting method of the Mini LED backlight channel light strip module is controlled, which solves the problem of poor transition smoothness of the Mini LED backlight channel light strip and cumbersome debugging, and realizes the effect of instantaneous current value reduction and smooth brightness smoothness. promote.
Patent Information
- Application Number
- CN202420489034.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-13
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2034-03-13
AI Technical Summary
The existing Mini LED backlight channel light strip has poor picture brightness transition effect, and the debugging method is cumbersome and time-consuming. The phase delay function of the backlight chip is difficult to achieve in high-partition solutions and has poor results.
Multiple switch units are used to control the multi-group backlight strip modules to light up in sequence, instead of the backlight chip's phase error delay technology, and the switching order of the backlight strip module is controlled by grouping method, reducing the instantaneous current value and improving the smooth transition of brightness. Effect.
It achieves the improvement of smooth transition of picture brightness, simplifies the debugging process, reduces power stress, and does not require individual debugging of each Mini LED backlight channel light bar, and the debugging method is simple and fast.
Smart Images
Figure CN222192596U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of electronic circuits, and in particular to a Mini LED backlight channel light bar control circuit and a display device. Background Art
[0002] The Mini LED backlight channel light strips in the backlight module of the display device often use regional dimming to control the backlight. Regional dimming can be used to control the brightness of the specified area of the screen to achieve a smooth transition in the brightness of the screen display. In the existing regional dimming method, if all the Mini LED backlight channel light strips in the backlight module partition are turned on at the same time, the instantaneous value of the generated current will be large, so that the power supply is subjected to greater stress and the protection function is easily triggered. In order to solve the problem of causing the power supply to be subjected to greater stress and easily triggering the protection function, the prior art usually uses the phase-shifting delay function of the backlight chip in the backlight module. This function allows the backlight module partition controlled by the backlight chip to stagger the opening and closing times of the Mini LED backlight channel light strips within a Vsync (vertical synchronization) cycle to achieve the requirement of reducing the dynamic load capacity of the power supply. However, the use of the staggered phase delay function of the backlight chip requires that the light strips controlled by the backlight chip are evenly distributed in the backlight module, which requires engineers to manually adjust the switching order of the backlight chip channels of each channel. This adjustment method is very cumbersome and time-consuming, and is not easy to implement in high-partition backlight module solutions. In addition, the smooth brightness transition of the picture achieved by the staggered phase delay function of the backlight chip is not good, and its feasibility in practical applications is low.
[0003] Therefore, in order to solve the above problems, the utility model provides a Mini LED backlight channel light bar control circuit and display device which can reduce the stress of the power board and have a smoother picture brightness transition effect. Utility Model Content
[0004] The utility model provides a Mini LED backlight channel light bar control circuit and a display device, aiming to solve the problems of poor smooth transition of picture brightness of existing Mini LED backlight channel light bars and complicated debugging methods.
[0005] In order to solve the above technical problems, the utility model provides a Mini LED backlight channel light bar control circuit on the one hand, which includes: a backlight light bar unit, which includes multiple groups of backlight light bar modules, and the multiple groups of backlight light bar modules are used to light up according to the brightness signal sent by the backlight chip; a switch unit, which includes multiple groups of switch modules, and the number of the multiple groups of switch modules is the same as the number of the multiple groups of backlight light bar modules. One end of the switch module is connected to the corresponding backlight light bar module, and the other end is used to receive the control signal sent by the backlight chip, and the multiple groups of switch modules are used to control the multiple groups of backlight light bar modules to light up in sequence according to the control signal and the brightness signal.
[0006] Furthermore, the backlight bar module includes a first group of backlight bar sub-modules, a second group of backlight bar sub-modules and a third group of backlight bar sub-modules, the first group of backlight bar sub-modules includes a first backlight bar and a second backlight bar; the first backlight bar, the second group of backlight bar sub-modules, the second backlight bar and the third group of backlight bar sub-modules are arranged in sequence, and the first group of backlight bar sub-modules, the second group of backlight bar sub-modules and the third group of backlight bar sub-modules are all connected to the backlight chip and the switch unit.
[0007] Furthermore, the switch unit includes a first switch module, a second switch module and a third switch module, one end of the first switch module is connected to the first group of backlight strip sub-modules, and the other end is used to receive the control signal; one end of the second switch module is connected to the second group of backlight strip sub-modules, and the other end is used to receive the control signal; one end of the third switch module is connected to the third group of backlight strip sub-modules, and the other end is used to receive the control signal.
[0008] Furthermore, the first switch module, the second switch module and the third switch module all include a control switch and an isolation module, the first connection end of the control switch is used to receive the control signal, the second connection end of the control switch is connected to one end of the isolation module, the other end of the isolation module is connected to the corresponding backlight bar module, and the third connection end of the control switch is grounded.
[0009] Furthermore, the first switch module, the second switch module and the third switch module all include a first resistor, one end of the first resistor is used to be connected to the input voltage, and the other end is connected to the control switch and the isolation module.
[0010] Furthermore, the control switch is a transistor, the base of the transistor is used to receive the control signal, the collector of the transistor is connected to the isolation module and the first resistor, and the emitter of the transistor is grounded.
[0011] Furthermore, the isolation module includes a plurality of isolation diodes, an anode of each isolation diode is connected to the backlight bar unit, and a cathode of the isolation diode is connected to the collector of the transistor and the first resistor.
[0012] Furthermore, each group of the backlight bar modules also includes multiple MOS tubes and multiple second resistors, the gate of each of the MOS tubes is used to be connected to the backlight chip and the anode of the isolation diode, the drain of each of the MOS tubes is connected to the backlight bar module, the source of each of the MOS tubes is used to be connected to the backlight chip and one end of the second resistor, and the other end of the second resistor is grounded.
[0013] Furthermore, the Mini LED backlight channel light bar control circuit also includes a control unit, which includes multiple backlight chips, and the sampling pin of each backlight chip is connected to the source of the MOS tube; the brightness signal output pin of each backlight chip is connected to the gate of the MOS tube; and the control signal pin of each backlight chip is connected to the base of the transistor.
[0014] On the other hand, the utility model further provides a display device, which includes the above-mentioned Mini LED backlight channel light bar control circuit.
[0015] The Mini LED backlight channel light bar control circuit and display device disclosed in the utility model replace the staggered phase delay technology of the backlight chip itself by controlling multiple groups of backlight light bar modules to light up in sequence through multiple groups of switch units, which can not only reduce the instantaneous value of the current of the backlight light bar unit at startup, but also provide a better smooth transition effect of the picture brightness; and multiple Mini LED backlight channel light bars are integrated into multiple groups of backlight light bar modules in a grouping manner, and the switching order of each group of backlight light bar modules is staggered in a grouping manner, so there is no need to debug each Mini LED backlight channel light bar separately, and the debugging method is simple, fast and easy to implement. The Mini LED backlight channel light bar control circuit disclosed in the utility model solves the problem that the existing Mini LED backlight channel light bar has a poor smooth transition effect of picture brightness and a complicated debugging method. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0017] Figure 1It is a structural schematic diagram of a Mini LED backlight channel light bar control circuit provided by an embodiment of the utility model;
[0018] Figure 2 This is a schematic diagram of the arrangement of the backlight strip modules provided in one embodiment of the utility model;
[0019] Figure 3 It is a schematic diagram of the arrangement and distribution of the backlight strip module in the prior art;
[0020] Figure 4 This is a circuit schematic diagram of a switch unit provided in one embodiment of the utility model;
[0021] Figure 5 This is a circuit schematic diagram of a plurality of backlight strip modules provided in one embodiment of the utility model;
[0022] Figure 6 It is a circuit schematic diagram of a control unit provided in one embodiment of the utility model;
[0023] Figure 7 This is a schematic diagram of the timing of turning on multiple groups of backlight strip modules provided by an embodiment of the utility model;
[0024] Figure 8 It is a structural schematic diagram of a display device provided by an embodiment of the utility model;
[0025] Reference numerals:
[0026] 10. Mini LED backlight channel light bar control circuit; 11. Backlight light bar unit; 111. Backlight light bar module; 1111. First group of backlight light bar sub-modules; 11111. First backlight light bar; 11112. Second backlight light bar; 1112. Second group of backlight light bar sub-modules; 1113. Third group of backlight light bar sub-modules; 1114. Second resistor; 12. Switch unit; 121. Switch module; 1211. First switch module; 1212. Second switch module; 122. First resistor; 13. Control switch; 14. Isolation module; 141. Isolation diode; 15. Control unit; 100. Display device. DETAILED DESCRIPTION
[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0028] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.
[0029] It should also be understood that the terms used in this utility model specification are only for the purpose of describing specific embodiments and are not intended to limit the utility model. As used in this utility model specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.
[0030] It should be further understood that the term “and / or” used in the present specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.
[0031] Figures 1 to 8 An embodiment of the Mini LED backlight channel light bar control circuit provided by the utility model is shown. The Mini LED backlight channel light bar control circuit 10 of this embodiment includes a backlight light bar unit 11 and a switch unit 12, wherein the backlight light bar unit 11 includes a plurality of backlight light bar modules 111, and the plurality of backlight light bar modules 111 are used to light up according to the brightness signal sent by the backlight chip; the switch unit 12 includes a plurality of switch modules 121, and the number of the plurality of switch modules 121 is the same as the number of the plurality of backlight light bar modules 111, one end of the switch module 121 is connected to the corresponding backlight light bar module 111, and the other end is used to receive the control signal sent by the backlight chip, and the plurality of switch modules 121 are used to control the plurality of backlight light bar modules 111 to light up in sequence according to the control signal and the brightness signal. In this embodiment, multiple groups of backlight strip modules 111 are controlled to light up in sequence by multiple groups of switch units 12 to replace the phase-shifting delay technology of the backlight chip itself, which can not only reduce the instantaneous value of the current of the backlight strip unit 11 at startup, but also provide a better smooth transition effect of the picture brightness; and multiple Mini LED backlight channel light strips are integrated into multiple groups of backlight strip modules 111 in a grouped manner, and the switching order of each group of backlight strip modules 111 is staggered in a grouped manner, without the need to debug each Mini LED backlight channel light strip separately, and the debugging method is simple, fast and easy to implement.
[0032] In one embodiment, such as this embodiment, Figure 2 As shown, the backlight strip module 111 includes a first group of backlight strip sub-modules 1111 (i.e. Figure 2The orange part in the middle), the second group of backlight strip submodules 1112 (i.e. Figure 2 The green part) and the third group of backlight strip submodules 1113 (i.e. Figure 2 The first backlight strip submodule 1111 includes a first backlight strip 11111 and a second backlight strip 11112; the first backlight strip 11111, the second backlight strip submodule 1112, the second backlight strip 11112 and the third backlight strip submodule 1113 are arranged in sequence, and the first backlight strip submodule 1111, the second backlight strip submodule 1112 and the third backlight strip submodule 1113 are all connected to the backlight chip and the switch unit 12. It should be noted that in this embodiment, Figure 2 The numbers in the figure represent the number of each backlight channel. Each backlight channel has a corresponding Mini LED backlight strip.
[0033] It should be noted that, in this embodiment, please refer to Figure 3 , Figure 3 This is a schematic diagram of the distribution of backlight strip module settings in the prior art. Figure 3 Each number represents a backlight channel light bar, from Figure 3 It can be seen from the figure that the prior art requires that the backlight chip be evenly distributed in the backlight partition when realizing the staggered phase delay function. This requires staggered phase delay to be performed according to a single channel light bar, which is different from the embodiment of the present invention. Figure 2 Compared with the grouping method used in Figure 2 The grouping method in can save adjustment time.
[0034] In one embodiment, such as this embodiment, Figure 4 As shown, the multiple groups of switch units 12 include a first switch module 1211, a second switch module 1212 and a third switch module (not shown in the figure), one end of the first switch module 1211 is connected to the first group of backlight bar sub-modules 1111, and the other end is used to receive the control signal; one end of the second switch module 1212 is connected to the second group of backlight bar sub-modules 1112, and the other end is used to receive the control signal; one end of the third switch module is connected to the third group of backlight bar sub-modules 1113, and the other end is used to receive the control signal. Specifically, the first switch module 1211, the second switch module 1212 and the third switch module each include a control switch 13 and an isolation module 14, the first connection end of the control switch 13 is used to receive the control signal, the second connection end of the control switch 13 is connected to one end of the isolation module 14, the other end of the isolation module 14 is connected to the corresponding backlight bar module 111, and the third connection end of the control switch 13 is grounded. It should be noted that, in this embodiment, Figure 4 Only two groups of switch modules are shown, which are respectively connected to corresponding backlight strip sub-modules to control the lighting of the corresponding connected backlight strip sub-modules. It can be understood that the number of backlight strip modules 111 included in the backlight strip unit 11 and the number of switch modules 121 included in the switch unit 12 can be set according to actual application requirements and are not limited to the above-mentioned number limits. This application does not make specific limitations here. The above-mentioned number settings are only used as examples of embodiments.
[0035] Furthermore, the first switch module 1211 , the second switch module 1212 and the third switch module all include a first resistor 121 , one end of the first resistor 121 is used to be connected to the input voltage Vref, and the other end is connected to the control switch 13 and the isolation module 14 .
[0036] Further, the control switch 13 is a transistor, the base of the transistor is used to receive the control signal, the collector of the transistor is connected to the isolation module 14 and the first resistor 122, and the emitter of the transistor is grounded. The isolation module 14 includes a plurality of isolation diodes 141, the anode of each isolation diode 141 is connected to the backlight bar unit 11 (that is, the anode of each isolation diode 141 is connected to its corresponding backlight bar module), and the cathode of the isolation diode 141 is connected to the collector of the transistor and the first resistor 122. Among them, the isolation diode 141 is used to isolate signals of different channels. It should be noted that, in this embodiment, the transistor is an NPN transistor.
[0037] In one embodiment, such as this embodiment, Figure 4 and Figure 5 As shown, each group of the backlight strip module 111 further includes a plurality of MOS tubes and a plurality of second resistors 1114, the gate of each MOS tube is used to be connected to the backlight chip and the anode of the isolation diode 141, the drain of each MOS tube is connected to the backlight strip module 111, the source of each MOS tube is used to be connected to the backlight chip and one end of the second resistor 1114, and the other end of the second resistor 1114 is grounded. It should be noted that in this embodiment, the MOS tube is an NMOS tube.
[0038] In one embodiment, such as this embodiment, Figure 6As shown, the Mini LED backlight channel light bar control circuit 10 also includes a control unit 15, and the control unit 15 includes a plurality of the backlight chips, and the sampling pin of each of the backlight chips is connected to the source of the MOS tube, so as to collect the current on the source of each MOS tube; the brightness signal output pin of each of the backlight chips is connected to the gate of the MOS tube, so as to control the on and off of the light bar in the backlight light bar module 111 through the brightness signal; the control signal pin of each of the backlight chips is connected to the base of the transistor, and the conduction and closing of the switch module 121 are controlled through the control signal.
[0039] For ease of understanding, the working process of the Mini LED backlight channel light bar control circuit 10 of the present invention to realize staggered phase delay to control multiple groups of backlight light bar modules 111 to light up in sequence is described as follows:
[0040] By connecting multiple groups of backlight strip modules 111 with corresponding switch modules 121, that is, connecting the first group of backlight strip sub-modules 1111 with the first switch module 1211, connecting the second group of backlight strip sub-modules 1112 with the second switch module 1212, and connecting the third backlight strip sub-module 1113 with the third switch module, when the control signal received by the control end of the switch module 121 (that is, the base of the transistor) is a high level, the transistor is turned on, and all the backlight strip modules 111 are clamped to a low level (that is, the gate of the MOS tube is a low level). At this time, all the backlight strip modules 111 cannot be turned on and lit.
[0041] See also Figure 7 , Figure 7 This is a schematic diagram of the timing for turning on multiple groups of backlight strip modules. During the Vsync signal cycle, when the backlight strip module 111 needs to be controlled to turn on and light up, the gates of the MOS tubes of all the backlight strip modules 111 will receive the brightness signal (high level) sent by the backlight chip. However, since all the backlight strip modules 111 are clamped at a low level by the switch module 121 at this time, the backlight strips at this time still cannot be turned on and light up. Therefore, it is necessary to change the level signal of the base of the transistor to control the backlight strip module 111 to turn on the circuit. First, the base of the transistor of the first switch module 1211 is changed from a high level to a low level. At this time, the brightness signal on the gate of the MOS tube of the first group of backlight strip sub-modules 1111 takes effect, and the MOS tube is turned on, correspondingly turning on and lighting up the light strips in the first group of backlight strip sub-modules. Then, by analogy, the control signals of the second switch module 1212 and the third switch module are changed in turn, so as to realize lighting up multiple groups of backlight strip modules 111 in turn. From Figure 7 It can be seen from the figure that there is a time delay in the phases of the control signal 1 and the control signal 2, and this time delay can achieve a phase-shifting delay effect of the multiple groups of backlight strip modules 111.
[0042] To sum up, by utilizing multiple groups of switch modules 121 to achieve staggered phase delay, the stress on the power board of the backlight strip circuit when it is started can be reduced; moreover, it has been verified through actual application that the staggered phase delay of the switch module 121 of this embodiment can allow a smooth transition of brightness when the display screen switches, and the screen display effect is better; in addition, compared with the existing staggered phase delay utilizing the backlight chip itself, the staggered phase delay of this embodiment simplifies the process and debugging, which can not only reduce the MCU cost, but also save time and labor costs.
[0043] In an embodiment, such as this embodiment, a display device 100 is also provided. Figure 8 The display device 100 includes the above-mentioned Mini LED backlight channel light bar control circuit 10, wherein the Mini LED backlight channel light bar control circuit 10 includes a control unit 15, a backlight light bar unit 11 and a switch unit 12, and the control unit 15 is connected to the backlight light bar unit 11 and the switch unit 12, and is used to send a brightness signal to the backlight light bar unit 11, and send a control signal to the switch unit 12, so as to control multiple groups of backlight light bar modules 111 to light up in sequence through the control signal and the brightness signal.
[0044] The Mini LED backlight channel light bar control circuit and display device provided by the utility model replace the staggered phase delay technology of the backlight chip itself by controlling multiple groups of backlight light bar modules to light up in sequence through multiple groups of switch units, which can not only reduce the instantaneous value of the current of the backlight light bar unit at startup, but also provide a better smooth transition effect of the picture brightness; and multiple Mini LED backlight channel light bars are integrated into multiple groups of backlight light bar modules by grouping, and the switching order of each group of backlight light bar modules is staggered in a grouping manner, so there is no need to debug each Mini LED backlight channel light bar separately, and the debugging method is simple, fast and easy to implement. The Mini LED backlight channel light bar control circuit disclosed by the utility model solves the problem that the existing Mini LED backlight channel light bar has a poor smooth transition effect of picture brightness and a complicated debugging method.
[0045] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the utility model, and these modifications or replacements should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.
Claims
1. A Mini LED backlight channel light bar control circuit, characterized in that: include: A backlight bar unit, comprising a plurality of backlight bar modules, wherein the plurality of backlight bar modules are used to light up according to brightness signals sent by the backlight chip; The switch unit comprises a plurality of switch modules, wherein the number of the plurality of switch modules is the same as the number of the plurality of backlight strip modules, one end of the switch module is connected to the corresponding backlight strip module, and the other end is used to receive a control signal sent by the backlight chip, and the plurality of switch modules are used to control the plurality of backlight strip modules to light up in sequence according to the control signal and the brightness signal.
2. The Mini LED backlight channel light bar control circuit according to claim 1, characterized in that: The backlight bar module includes a first group of backlight bar sub-modules, a second group of backlight bar sub-modules and a third group of backlight bar sub-modules, the first group of backlight bar sub-modules includes a first backlight light bar and a second backlight light bar; the first backlight light bar, the second group of backlight light bar sub-modules, the second backlight light bar and the third group of backlight light bar sub-modules are arranged in sequence, and the first group of backlight light bar sub-modules, the second group of backlight light bar sub-modules and the third group of backlight light bar sub-modules are all connected to the backlight chip and the switch unit.
3. The Mini LED backlight channel light bar control circuit according to claim 2, characterized in that: The switch unit includes a first switch module, a second switch module and a third switch module, one end of the first switch module is connected to the first group of backlight bar sub-modules, and the other end is used to receive the control signal; one end of the second switch module is connected to the second group of backlight bar sub-modules, and the other end is used to receive the control signal; one end of the third switch module is connected to the third group of backlight bar sub-modules, and the other end is used to receive the control signal.
4. The Mini LED backlight channel light bar control circuit according to claim 3, characterized in that: The first switch module, the second switch module and the third switch module all include a control switch and an isolation module. The first connection end of the control switch is used to receive the control signal, the second connection end of the control switch is connected to one end of the isolation module, the other end of the isolation module is connected to the corresponding backlight strip module, and the third connection end of the control switch is grounded.
5. The Mini LED backlight channel light bar control circuit according to claim 4, characterized in that: The first switch module, the second switch module and the third switch module all include a first resistor, one end of the first resistor is used to be connected to the input voltage, and the other end of the first resistor is connected to the control switch and the isolation module.
6. The Mini LED backlight channel light bar control circuit according to claim 5, characterized in that: The control switch is a triode, the base of the triode is used to receive the control signal, the collector of the triode is connected to the isolation module and the first resistor, and the emitter of the triode is grounded.
7. The Mini LED backlight channel light bar control circuit according to claim 6, characterized in that: The isolation module includes a plurality of isolation diodes, an anode of each isolation diode is connected to the backlight bar unit, and a cathode of the isolation diode is connected to the collector of the transistor and the first resistor.
8. The Mini LED backlight channel light bar control circuit according to claim 7, characterized in that: Each group of the backlight strip modules also includes multiple MOS tubes and multiple second resistors, the gate of each MOS tube is used to be connected to the backlight chip and the anode of the isolation diode, the drain of each MOS tube is connected to the backlight strip module, the source of each MOS tube is used to be connected to the backlight chip and one end of the second resistor, and the other end of the second resistor is grounded.
9. The Mini LED backlight channel light bar control circuit according to claim 8, characterized in that: The Mini LED backlight channel light bar control circuit also includes a control unit, which includes multiple backlight chips, a sampling pin of each backlight chip is connected to the source of the MOS tube; a brightness signal output pin of each backlight chip is connected to the gate of the MOS tube; and a control signal pin of each backlight chip is connected to the base of the transistor.
10. A display device, characterized in that: The display device includes a Mini LED backlight channel light bar control circuit as described in any one of claims 1-9.