LED drive circuit, backlight system and display device

Abstract

The utility model provides an LED drive circuit, a backlight system and a display device, and the LED drive circuit comprises an image processing unit which is used for outputting a dimming signal in a first data format through a first pin; the input end of the driving unit is connected with the first pin, and the output end of the driving unit is connected with the second pin of the image processing unit; the driving unit is used for receiving the dimming signal and outputting a feedback signal according to the dimming signal; according to the LED driving circuit, the image processing unit is directly communicated with the driving unit, so that a driving control unit in an existing LED driving circuit is omitted, the circuit design is simplified, and the circuit cost is reduced.

Description

Technical Field

[0001] The utility model relates to the field of backlight display, in particular to an LED drive circuit, a backlight system and a display device. Background Art

[0002] With the continuous development of LED drivers, user experience is also constantly upgrading. Now the backlight partitions of LCD display products (such as LCD TVs, LCD screens, etc.) can reach 5,000 partitions, or even tens of thousands of partitions.

[0003] However, in addition to application scenarios such as LCD TVs and LCD screens that require a high number of partitions, there are other application scenarios that do not require a high number of backlight partitions. Therefore, in application scenarios that do not require a high number of backlight partitions, existing LED drive circuits have the problems of complex circuits and high circuit costs.

[0004] Therefore, providing an LED driving circuit with a simple circuit, low circuit cost and suitable for application scenarios has become a technical problem that the industry urgently needs to solve. Utility Model Content

[0005] The technical problem solved by the utility model is to provide an LED driving circuit, a backlight system and a display device, which solve the problems of complex circuits and high circuit costs in the existing LED driving circuits.

[0006] In order to solve the above technical problems, the present utility model provides an LED driving circuit, comprising:

[0007] An image processing unit, the image processing unit being configured to output a dimming signal in a first data format through a first pin;

[0008] A driving unit, wherein the input end of the driving unit is connected to the first pin, and the output end of the driving unit is connected to the second pin of the image processing unit; the driving unit is used to receive the dimming signal and output a feedback signal according to the dimming signal.

[0009] Optionally, the driving unit includes several driving sub-units connected in series, the input end of the first driving sub-unit serves as the input end of the driving unit, the output end of each driving sub-unit is connected to the input end of an adjacent driving sub-unit, and the output end of the last driving sub-unit serves as the output end of the driving unit.

[0010] Optionally, the first pin is specifically a MOSI pin.

[0011] Optionally, the image processing unit further includes an SPI interface, and the MOSI pin is arranged in the SPI interface.

[0012] Optionally, the second pin is specifically a RX pin.

[0013] Optionally, the image processing unit further includes a UART interface, and the RX pin is arranged in the UART interface.

[0014] Optionally, the driving unit specifically includes an LED driving chip.

[0015] Optionally, the image processing unit includes at least any one of a system-level chip, an image quality enhancement chip and a screen driving chip.

[0016] Correspondingly, the technical solution of the utility model further provides a backlight system, including the LED driving circuit provided by the technical solution of the utility model.

[0017] Correspondingly, the technical solution of the present utility model further provides a display device, including the backlight system provided by the technical solution of the present utility model.

[0018] Compared with the prior art, the technical solution of the embodiment of the utility model has the following beneficial effects:

[0019] In the LED driving circuit of the technical solution of the utility model, the image processing unit directly communicates with the driving unit, eliminating the driving control unit in the existing LED driving circuit, thereby simplifying the circuit design and reducing the circuit cost.

[0020] Furthermore, since the MOSI pin of the SPI interface and the RX pin of the UART interface are both interface pins provided by the image processing unit, the circuit cost is further reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a circuit structure schematic diagram of an embodiment of an LED driving circuit;

[0022] Figure 2 The circuit structure diagram of the LED driving circuit provided by the technical solution of the utility model is as follows Figure 1 ;

[0023] Figure 3 The circuit structure of the LED driving circuit provided by the embodiment of the utility model is shown in FIG. Figure 2 .

[0024] Reference numerals:

[0025] 10- Image processing unit;

[0026] 20- drive unit;

[0027] 21- driving subunit;

[0028] 101-first pin;

[0029] 102 - second pin. DETAILED DESCRIPTION

[0030] As described in the background art, the existing LED driving circuit has the problems of complex circuit and high circuit cost, which will be described in detail below with reference to the accompanying drawings.

[0031] Figure 1 The present invention is a circuit structure diagram of an embodiment of an LED driving circuit.

[0032] Please refer to Figure 1 , Figure 1 The LED driving circuit shown includes an image processing unit, a driving control unit and several links of LED driving units. The image processing unit generates a dimming signal and transmits it to the driving control unit via an SPI interface. The driving control unit converts the received dimming signal into a data format that can be received by the LED driving unit, transmits it to the LED driving unit of the corresponding link, and receives feedback information from the LED driving unit of the corresponding link.

[0033] Figure 1 The LED driving circuit shown is suitable for display products that have high requirements for the number of backlight partitions, such as liquid crystal resistors, liquid crystal display screens, etc. However, for display products that do not require the number of backlight partitions and pay more attention to product cost, Figure 1 The LED driving circuit shown has the problems of complex circuit and high circuit cost.

[0034] In view of this, the technical solution of the utility model provides a new LED driving circuit.

[0035] in, Figure 2 The circuit structure diagram of the LED driving circuit provided by the technical solution of the utility model is as follows Figure 1 .

[0036] Please refer to Figure 2 The LED driving circuit provided by the technical solution of the utility model includes:

[0037] An image processing unit 10, wherein the image processing unit 10 is configured to output a dimming signal in a first data format through a first pin 101;

[0038] The driving unit 20 has an input end connected to the first pin 101 and an output end connected to the second pin 102 of the image processing unit 10; the driving unit 20 is used to receive the dimming signal and output a feedback signal according to the dimming signal.

[0039] Through the above technical means, the utility model realizes a LED driving circuit with simple circuit and low circuit cost. The specific principle is as follows:

[0040] The dimming signal in the first data format is directly output to the input end of the driving unit 20 through the first pin 101 of the image processing unit 10, so that the driving unit 20 outputs the feedback signal according to the dimming signal, and feeds the feedback signal back to the second pin 102 of the image processing unit 10. Figure 1 The driving control unit in the LED driving circuit shown simplifies the circuit design and reduces the circuit cost.

[0041] In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0042] Figure 3 The circuit structure of the LED driving circuit provided by the embodiment of the utility model is shown in FIG. Figure 2 .

[0043] Please refer to Figure 3 As a specific implementation, the driving unit 20 includes a plurality of driving subunits 21 connected in series, the input end of the first driving subunit 21 serves as the input end of the driving unit 20, the output end of each driving subunit 21 is connected to the input end of the adjacent driving subunit 21, and the output end of the last driving subunit 21 serves as the output end of the driving unit 20. The following is a description of the workflow of a plurality of driving subunits 21 connected in series outputting the feedback signal according to the received dimming signal:

[0044] After the image processing unit 10 completes the address editing of each driver unit 21. The graphics processing unit will output a dimming signal according to the different requirements for each driver unit 21. The dimming signal is generally a data packet, which contains task instructions for each driver unit 21 and a data space for storing the output information of the driver unit 21. Among them, the task instructions for each driver unit 21 may include a control task for the driver unit 21 and a reading task for reading the data stored in the driver unit 21. After receiving the dimming signal, the first driver unit 21 will call the task instruction corresponding to its own address. If the first driver unit 21 has data that needs to be read, the first driver unit 21 will upload the data to the data packet and output the data packet to the adjacent driver unit 21 behind. The subsequent driver unit 21 will also call and complete the task instruction corresponding to its own address, and output the data packet to the adjacent driver unit 21 behind, until the last driver unit 21 outputs the data packet to the second pin 102 of the image processing unit 10, that is, output the feedback signal.

[0045] Specifically, the driving unit 20 includes an LED driving chip. The specific model of the LED driving chip can be selected according to the needs and is not limited here.

[0046] Please refer to Figure 3 As a specific implementation, the first data format is specifically a data format that can be received and used by the driving unit 20. For example, the first data format includes BMC-coded data or data that identifies binary "0" and "1" according to the duty cycle. Of course, the specific format of the first data format can be selected according to the specific needs of the driving subunit 21 and is not limited here.

[0047] Please refer to Figure 3 As a specific implementation, the first pin 101 is specifically a MOSI pin in the SPI interface of the image processing unit 10. The first pin 101 is specifically a RX pin in the UART interface of the image processing unit 10.

[0048] The above embodiment has the beneficial effect that the communication with the driving unit 20 is completed through the pins provided by default on the image processing unit 10, thereby further reducing the circuit cost. The specific principle is as follows:

[0049] The image processing unit 10 generally includes at least one of a system-level chip, a picture quality enhancement chip and a screen driver chip. Of course, other chips with data processing functions are not excluded and are not limited here. The above-mentioned chip applied to the image processing unit 10 usually has an additional set of SPI interfaces and UART interfaces. The MOSI pin in the SPI interface supports sending data to the outside in serial mode, and the RX pin in the UART interface can receive serial data. Therefore, the dimming signal can be sent through the MOSI pin provided on the image processing unit 10, and the feedback signal can be received through the RX pin provided on the image processing unit 10, thereby realizing the communication between the image processing unit 10 and the driver unit 20.

[0050] It should be noted that, in addition to the MOSI pin in the SPI interface, the first pin 101 can also be replaced by a pin in the USART interface. Of course, other hardware interfaces that can continuously send bit data streams can be used as the first pin 101, and there is no limitation here. Similarly, other hardware interfaces that can continuously receive bit data streams can also be used as the second pin 102, and there is no limitation here.

[0051] In summary, the LED driving circuit provided by the embodiment of the utility model directly communicates with a plurality of driving units connected in series, eliminating the driving control unit in the existing LED driving circuit, thereby simplifying the circuit design and reducing the circuit cost.

[0052] Furthermore, the first pin is a MOSI pin of the SPI interface, and the second pin is a RX pin of the UART interface. Since the MOSI pin of the SPI interface and the RX pin of the UART interface are both interface pins provided by the image processing unit, the circuit cost is further reduced.

[0053] The technical solution of the utility model also provides a backlight system, including the LED driving circuit.

[0054] The technical solution of the utility model also provides a display device, including the backlight system.

[0055] Although the utility model is disclosed as above, the utility model is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the utility model. Therefore, the protection scope of the utility model shall be subject to the scope defined by the claims.

Claims

1. An LED driving circuit, characterized in that: include: An image processing unit, the image processing unit being configured to output a dimming signal in a first data format through a first pin; A driving unit, wherein the input end of the driving unit is connected to the first pin, and the output end of the driving unit is connected to the second pin of the image processing unit; the driving unit is used to receive the dimming signal and output a feedback signal according to the dimming signal.

2. The LED driving circuit according to claim 1, characterized in that: The driving unit includes a plurality of driving subunits connected in series, the input end of the first driving subunit serves as the input end of the driving unit, the output end of each driving subunit is connected to the input end of an adjacent driving subunit, and the output end of the last driving subunit serves as the output end of the driving unit.

3. The LED driving circuit according to claim 1, characterized in that: The first pin is specifically a MOSI pin.

4. The LED driving circuit according to claim 3, characterized in that: The image processing unit also includes an SPI interface, and the MOSI pin is arranged in the SPI interface.

5. The LED driving circuit according to claim 1, characterized in that: The second pin is specifically a RX pin.

6. The LED driving circuit according to claim 5, characterized in that: The image processing unit further comprises a UART interface, and the RX pin is arranged in the UART interface.

7. The LED driving circuit according to claim 1, characterized in that: The driving unit specifically includes an LED driving chip.

8. The LED driving circuit according to claim 1, characterized in that: The image processing unit includes at least one of a system-level chip, a picture quality enhancement chip and a screen driving chip.

9. A backlight system, characterized in that: The LED driving circuit comprises the LED driving circuit according to any one of claims 1 to 8.

10. A display device, characterized in that: The backlight system comprises the backlight system described in claim 9.

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