KR102648889B1 - Light emitting diode driving device and display device for local dimming - Google Patents

Abstract

An LED driving device that generates LED (light emitting diode) driving currents based on input signals includes a first pin group and a second pin group facing each other in a first direction, and a second pin group facing each other in a second direction orthogonal to the first direction. may include a third pin group and a fourth pin group, the first pin group may include pins that receive input signals, and the second pin group may be provided to an adjacent LED driving device in the first direction. may include pins that output output signals generated based on input signals, and a third pin group may include pins that draw LED driving currents from a plurality of LEDs, and a fourth pin group may include pins that receive supply voltages that provide power to the LED driving device.

Description

LED driving device and display device for local dimming {LIGHT EMITTING DIODE DRIVING DEVICE AND DISPLAY DEVICE FOR LOCAL DIMMING}

The technical idea of the present disclosure relates to driving a light emitting diode (LED), and more specifically, to an LED driving device and a display device for local dimming.

Light emitting diodes (LEDs) are used in a variety of applications due to their advantageous properties such as low power consumption and small size. For example, LED can be used as a backlight for a display, and as an example of using LED as a backlight, mini LED closely arranges LEDs of small size (e.g., hundreds of μm) and adjusts the brightness of the LED according to the display content. It can refer to a method of control. Such local dimming can achieve a detailed contrast ratio as the density of LEDs increases, that is, as the number of local dimming zones increases. Accordingly, it may be important to accurately and efficiently drive multiple LEDs in a mini LED.

The technical idea of the present disclosure provides an LED driving device and a display device for efficiently performing local dimming.

In order to achieve the above object, an LED driving device that generates LED (light emitting diode) driving currents based on input signals according to one aspect of the technical idea of the present disclosure includes a first pin facing in a first direction. A group and a second pin group, and a third pin group and a fourth pin group facing each other in a second direction orthogonal to the first direction, wherein the first pin group may include pins that receive input signals. The second pin group may include pins that output output signals generated based on input signals to be provided to an LED driving device adjacent to the first direction, and the third pin group may include a plurality of LEDs. and a fourth pin group may include pins that receive supply voltages that provide power to the LED driving device.

According to an exemplary embodiment of the present disclosure, the first pin group may include a first input pin that receives an input data signal including information about the magnitude of the LED driving current among the input signals, and a second pin The group may include a first output pin that outputs an output data signal generated based on an input data signal among the output signals, and the first input pin and the first output pin may face each other in a first direction. .

According to an exemplary embodiment of the present disclosure, the first pin group may include a second input pin that receives an input clock signal synchronized to an input data signal among the input signals, and the second pin group may include an output signal Among them, it may include a second output pin that outputs an output clock signal generated based on the input clock signal, and the second input pin and the second output pin may face each other in the first direction.

According to an exemplary embodiment of the present disclosure, the first pin group may include a third input pin that receives an input synchronization signal instructing update of LED driving currents, and the second pin group may include one of the output signals. It may include a third output pin that outputs a first output synchronization signal generated based on the input synchronization signal, and the third input pin and the third output pin may face each other in the first direction.

According to an exemplary embodiment of the present disclosure, the first pin group further includes a fourth output pin for outputting a second output synchronization signal generated based on the input synchronization signal to provide it to an adjacent LED driving device in the second direction. It may include, and the third input pin and fourth output pin may be arranged at the outermost part of the first pin group.

According to an exemplary embodiment of the present disclosure, the fourth pin group may include a first pin and a second pin configured to be applied with a positive supply voltage, and at least one third pin configured to be applied with a negative supply voltage. The third pin may be disposed between the first pin and the second pin in the fourth pin group.

According to an exemplary embodiment of the present disclosure, the LED driving device may further include a conductive member electrically connecting the first pin and the second pin.

According to an exemplary embodiment of the present disclosure, the conductive member may include at least one of a bonding wire, a pattern of a wiring layer, and a lead-frame.

According to an exemplary embodiment of the present disclosure, the fourth pin group may further include a fourth input pin that receives a mode signal for setting the mode of the LED driving device, and the LED driving device outputs output based on the mode. At least one of the signals may be generated differently.

According to an exemplary embodiment of the present disclosure, the LED driving device may identify the mode based on at least one of a voltage applied to the fourth input pin and an open state of the fourth input pin, and the fourth input pin is, It may be disposed between the first pin and the third pin in the fourth pin group.

A display device according to one aspect of the technical idea of the present disclosure includes a driver array including a plurality of LEDs (light emitting diodes), a plurality of LED driving devices each driving at least one of the plurality of LEDs, and a plurality of LEDs. It may include a substrate on which LEDs and a driver array are mounted, and the substrate includes a driver array, a plurality of first patterns connecting the plurality of LEDs, and a plurality of first patterns connecting adjacent LED driving devices in each row of the driver array. The second patterns may include a third pattern commonly connected to the LED driving devices in each of the rows of the driver array, and the plurality of first patterns, the plurality of second patterns, and the third pattern may include: It may be included in the same conductive layer.

According to an exemplary embodiment of the present disclosure, the plurality of second patterns include at least one second pattern transmitting at least one signal from a first LED driving device to a second LED driving device adjacent in the row direction, and a second It may include at least one second pattern that transfers a positive supply voltage from the LED driving device to the first LED driving device.

According to an exemplary embodiment of the present disclosure, the substrate may further include a plurality of fourth patterns connecting adjacent LED driving devices in each of the rows of the driver array, and the plurality of fourth patterns may be included in the conductive layer. You can.

According to an exemplary embodiment of the present disclosure, each of the plurality of LED driving devices may include a mode input pin for receiving a mode signal for setting a mode, and the plurality of LED driving devices may include a first maximum signal of the driver array. It may include a first group included in the outer column, a second group included in the second outermost column of the driver array, and a third group excluding the first group and the second group, and the substrate may include a first group of the first group. The mode input pins, the second group of mode input pins, and the third group of mode input pins may further include a plurality of fifth patterns arranged to mutually exclusively correspond to a positive supply voltage, a negative supply voltage, and an open state. and a plurality of fifth patterns may be included in the conductive layer.

According to the LED driving device and display device according to exemplary embodiments of the present disclosure, multiple LED driving devices can be controlled by a simple structure, and thus low cost, high productivity, and high reliability can be achieved.

In addition, according to the LED driving device and display device according to the exemplary embodiment of the present disclosure, the LED driving devices can be easily monitored, so errors or malfunctions can be easily detected and calibration can be easily performed. It can be.

The effects that can be obtained from the exemplary embodiments of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned are common knowledge in the technical field to which the exemplary embodiments of the present disclosure belong from the following description. It can be clearly derived and understood by those who have it. That is, unintended effects resulting from implementing the exemplary embodiments of the present disclosure may also be derived by those skilled in the art from the exemplary embodiments of the present disclosure.

FIG. 1 is a diagram illustrating a display device according to an exemplary embodiment of the present disclosure.
Figure 2 is a block diagram showing an example of a backlight unit according to example embodiments of the present disclosure.
Figure 3 is a block diagram showing an LED driving device according to an exemplary embodiment of the present disclosure.
Figure 4 is a timing diagram showing signals according to an exemplary embodiment of the present disclosure.
5A and 5B are timing diagrams showing signals according to example embodiments of the present disclosure.
Figure 6 is a diagram showing an LED driving device according to an exemplary embodiment of the present disclosure.
Figure 7 is a diagram showing a backlight unit according to an exemplary embodiment of the present disclosure.
8A to 8C are diagrams showing examples of the internal structure of a semiconductor package according to example embodiments of the present disclosure.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. Examples of the present invention are provided to more completely explain the present invention to those with average knowledge in the art. Since the present invention can be subject to various changes and can have various forms, specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to a specific disclosed form, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention. When describing each drawing, similar reference numerals are used for similar components. In the attached drawings, the dimensions of the structures are enlarged or reduced from the actual size to ensure clarity of the present invention.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless clearly defined in the present application, be interpreted as having an ideal or excessively formal meaning. It doesn't work.

FIG. 1 is a diagram illustrating a display device 100 according to an exemplary embodiment of the present disclosure. Specifically, FIG. 1 shows the backlight unit (BLU) 110 and the color panel 120 included in the display panel of the display device 100 separately for convenience of illustration.

The display device 100 may refer to any device that outputs content, that is, images or videos, through a display panel. For example, the display device 100 may be an independent device for display purposes, such as a TV or monitor, or may be included in the system as a part for a function that requires a display, such as a smart phone display, a vehicle cluster, etc. It may be possible. The display device 100 can output content in any manner using the backlight unit 110. For example, the backlight unit 110 and the color panel 120 may be included in a liquid crystal display (LCD) panel, and the color panel 120 includes a polarizer, a thin film transistor (TFT), liquid crystal, and a color filter. can do. Hereinafter, the display device 100 is assumed to include an LCD panel, but it is noted that the exemplary embodiments of the present disclosure are not limited thereto.

The backlight unit 110 may include a plurality of LEDs as light sources. For example, as shown in FIG. 1, the backlight unit 110 may include a plurality of LEDs arranged in an array. Light output from the LEDs of the backlight unit 110 may be output by combining colors corresponding to content by the color panel 120. The mini LED densely arranges LEDs of small sizes (e.g., hundreds of μm) in the backlight unit 110, and outputs the brightness of a local dimming zone consisting of at least one LED, that is, from the local dimming zone. It can refer to a method of adjusting the intensity of light depending on the content. These mini LEDs can solve the low contrast ratio of LCD displays, thereby enabling high-quality, low-cost display devices.

The higher the density of local dimming zones included in the backlight unit 110, the more precise local dimming may be possible, and as a result, a higher contrast ratio may be achieved. Accordingly, it is important not only to accurately control a plurality of local dimming zones included in the backlight unit 110, but also to control the local dimming zones at a high speed to respond to rapid changes in content (i.e., high frame rate). It can be important. Additionally, in order to reduce the cost of the display device 100, it may be advantageous to implement the backlight unit 110 at a low cost. Hereinafter, an LED driving device and a display device that provide advantages to mini LEDs will be described with reference to the drawings.

Figure 2 is a block diagram showing an example of a backlight unit according to example embodiments of the present disclosure. In the block diagram of FIG. 2, the backlight unit 200 is assumed to include 16 LED driving devices and provide 64 local dimming zones for convenience of illustration, but the exemplary embodiments are not limited thereto. It is noted. For example, backlight unit 110 of FIG. 1 may include less than 16 or more than 16 LED driving devices, each of which may correspond to less than 4 or more than 4 local dimming zones. there is. In some embodiments, one LED shown in FIG. 2 may correspond to a plurality of LEDs connected to each other in series and/or parallel.

Referring to FIG. 2, the backlight unit 200 may include a plurality of LEDs and a plurality of LED driving devices. For example, as shown in FIG. 2, the backlight unit 200 may include a plurality of LED driving devices 211 to 214 in a first row and a plurality of LED driving devices 211 to 214 in a second row. (221 to 224), may include a plurality of LED driving devices (231 to 234) in the third row, and may include a plurality of LED driving devices (241 to 244) in the fourth row. You can. In some embodiments, the LED driving device may correspond to one chip or one semiconductor package manufactured through a semiconductor process, and a plurality of LED driving devices included in the backlight unit 200 may be the same. For example, a plurality of LED driving devices included in the backlight unit 200 may be mounted on a board while being spaced apart from each other, and may be electrically connected to each other through a pattern formed on the board. In this specification, as shown in FIG. 2, a plurality of LED driving devices arranged in row and column directions may be referred to as a driver array.

Each of the plurality of LED driving devices can independently drive four LEDs corresponding to four local dimming zones, and for this purpose, generate four LED driving currents. An LED voltage (V _LED ) may be applied to a plurality of LEDs, and each of the plurality of LEDs may emit light with an intensity corresponding to the magnitude of the LED driving current.

The LED driving device may provide an output signal to adjacent LED driving devices in the row direction. For example, the input signal IN may include first dimming information for the LED driving device 211 and second dimming information for the LED driving device 212. The LED driving device 211 may generate an output signal (OUT11) corresponding to the input signal (IN) from which the first dimming information has been removed (or deactivated) and provide the output signal (OUT11) to the LED driving device 212. 212 may identify second dimming information from the output signal OUT11. Accordingly, overhead for addressing LED driving devices, such as a structure and/or operation for assigning a unique address to the LED driving device, and a structure and/or operation for providing an address of the LED driving device can be omitted. . For example, the signal path for controlling LED driving devices can be shortened, and the influence of parasitic components can be reduced due to the shortened signal path, so malfunctions and delays in LED control can be prevented. Additionally, productivity of the backlight unit 200 and the display device can be improved due to the simple structure.

In some embodiments, an LED driving device may add state information to an output signal provided to an LED driving device adjacent in the row direction. For example, the LED driving device 211 may generate an output signal (OUT11) including status information, and the LED driving device 212 may generate the LED included in the output signal (OUT11) as well as the state information of the LED itself. An output signal OUT12 containing status information of the driving device 211 may be generated. Accordingly, the LED driving device 214 located last in the row may generate an output signal (not shown) containing status information of the LED driving devices 211 to 214 included in the row. Accordingly, LED driving devices can be easily monitored.

As shown in FIG. 2, the LED driving devices 211, 221, 231, and 241 arranged in the first column may commonly receive the input signal IN. Each of the LED driving devices 211, 221, 231, and 241 can receive dimming information for all LED driving devices included in the input signal IN, while responding to its own dimming information by a synchronization signal to be described later. LED drive current can be generated to emit light of a certain intensity.

The LED driving device may receive a synchronization signal and provide the received synchronization signal or a delayed synchronization signal generated by delaying the synchronization signal to an LED driving device adjacent in the row direction. For example, the LED driving device 211 may generate a delayed synchronization signal from the vertical synchronization signal (VSYNC), and output signal OUT11 including the delayed synchronization signal to the LED driving device 212 adjacent in the row direction. can be provided. The LED driving device 212 may generate an output signal OUT12 including a synchronization signal that does not delay the synchronization signal included in the output signal OUT11. The LED driving device 211 may update the LED driving current based on a synchronization signal delayed from the vertical synchronization signal (VSYNC), while the LED driving devices 212 to 214 may update the LED driving current based on the synchronization signal included in the received output signal. Based on this, the LED driving current can be updated. Accordingly, LED driving devices included in one row can update LED driving currents at substantially the same time. The vertical synchronization signal (VSYNC) may be activated at a period corresponding to one frame section in the display device, and the brightness of each local dimming zone may vary on a frame-by-frame basis.

The LED driving device may receive a synchronization signal and provide a delayed synchronization signal generated by delaying the synchronization signal to an LED driving device adjacent in the column direction. For example, the LED driving device 211 may generate a delayed output synchronization signal (SOUT21) from the vertical synchronization signal (VSYNC) and provide the output synchronization signal (SOUT21) to the LED driving device 221 adjacent in the column direction. can do. Additionally, the LED driving device 221 can generate a delayed output synchronizing signal (SOUT22) from the output synchronizing signal (SOUT21) and provide the output synchronizing signal (SOUT22) to the LED driving device 231 adjacent in the column direction. there is. Accordingly, rows in the driver array may be sequentially updated.

Figure 3 is a block diagram showing an LED driving device 300 according to an exemplary embodiment of the present disclosure. For example, the block diagram of FIG. 3 shows an example of an LED driving device included in the backlight unit 200 of FIG. 2. In some embodiments, the LED driving devices included in the backlight unit 200 of FIG. 2 may have the same structure as the LED driving device 300 of FIG. 3. Hereinafter, FIG. 3 will be explained with reference to FIG. 2 .

Referring to FIG. 3, the LED driving device 300 may include a controller 320 and first to fourth LED driving devices 340. Each of the components of the LED driving device 300 may include a circuit designed to perform a unique function, and may include a logic gate in some embodiments. As shown in FIG. 3, the LED driving device 300 can receive an input signal (IN), an input synchronization signal (SIN), and an input mode signal (MIN), and an output signal (OUT) and a second output synchronization signal. A signal (SOUT2) can be output. Additionally, the LED driving device 300 may draw first to fourth LED driving currents (I _LED1 to I _LED4 ). As shown in FIG. 3, the input signal IN may include an input data signal DIN and an input clock signal CIN, and the output signal OUT may include a first output synchronization signal SOUT1 and an output data signal SOUT1. It may include a signal (DOUT) and an output clock signal (COUT).

The controller 320 may receive an input data signal (DIN), an input clock signal (CIN), and an input synchronization signal (SIN). For example, when the LED driving device 300 is disposed in the LED driving device 211 of FIG. 2, the input data signal (DIN) and the input clock signal (CIN) may be included in the input signal (IN) of FIG. 2. And the input synchronization signal (SIN) may correspond to the vertical synchronization signal (VSYNC) of FIG. 2. In addition, when the LED driving device 300 is disposed in the LED driving device 212 of FIG. 2, the input data signal (DIN), input clock signal (CIN), and input synchronization signal (SIN) are the output signal ( OUT11).

The controller 320 may identify dimming information by decoding the input data signal (DIN) based on the input clock signal (CIN). For example, the input data signal DIN may be synchronized to the input clock signal CIN, and the controller 320 may detect packets in the input data signal DIN based on the input clock signal CIN. . The controller 320 may extract dimming information from the detected packet and identify the sizes of the first to fourth LED driving currents (I _LED1 to I _LED4 ) corresponding to the dimming information.

The controller 320 may control the first to fourth LED driving devices 340 based on dimming information and the input synchronization signal (SIN). For example, when the input synchronization signal (SIN) is activated or when the synchronization signal delayed from the input synchronization signal (SIN) is activated, the controller 320 generates the first to fourth LED driving currents (I _LED1 to I _LED4 ) The control signal CTR may be generated to have a size corresponding to the dimming information identified based on the input data signal DIN and the input clock signal CIN.

The controller 320 may generate an output data signal (DOUT) and an output clock signal (COUT) based on the input data signal (DIN) and the input clock signal (CIN). For example, the controller 320 may generate an output data signal DOUT with the dimming information identified in the input data signal DIN removed (or disabled), and an output synchronized to the output data signal DOUT. A clock signal (COUT) can be generated. Additionally, the controller 320 may generate an output data signal DOUT including status information of the LED driving device 340. Accordingly, status information of the LED driving device 300 can be propagated, LED driving devices included in the backlight unit can be monitored, errors or malfunctions can be easily detected, and calibration can be easily performed. It can be done. The status information may include, as non-limiting examples, the size of the set LED driving current, the size of the sensed LED driving current, the detected LED voltage, temperature, etc.

The controller 320 may receive the input mode signal MIN and may be set to one of a plurality of modes according to the input mode signal MIN. For example, in the driver array of FIG. 2, the LED driving devices 211, 221, 231, and 241 included in the first column may be set to the first mode, and the LED driving devices 214 and 241 included in the last column may be set to the first mode. 224, 234, 244) can be set to the third mode, and the remaining LED driving devices (212, 213, 222, 223, 232, 233, 242, 243) can be set to the second mode. In the first mode, the controller 320 may generate a first output synchronization signal (SOUT1) and a second output synchronization signal (SOUT2) generated by delaying the input synchronization signal (SIN). In addition, the controller 320 updates the first to fourth LED driving currents ILED1 to ILED4 based on a synchronization signal delayed from the input synchronization signal SIN, for example, the first output synchronization signal SOUT1, in the first mode. A control signal (CTR) can be generated as much as possible. In the second mode, the controller 320 may not delay the input synchronization signal SIN and may generate the first output synchronization signal SOUT1 corresponding to the input synchronization signal SIN. In the third mode, the controller 320 may generate an output data signal DOUT that includes both the accumulated state information of the LED driving devices and the state information of the LED driving device 300. In the second mode and the third mode, the controller 320 may generate a control signal (CTR) to update the first to fourth LED driving currents (ILED1 to ILED4) based on the input synchronization signal (SIN).

Figure 4 is a timing diagram showing signals according to an exemplary embodiment of the present disclosure. For example, Figure 4 shows an example of the input signal (IN) and output signals (OUT11 to OUT14) of Figure 2. As described above with reference to FIG. 3, the input signal IN may include an input data signal DIN and an input clock signal CIN. Additionally, the output signal OUT11 may include an output data signal DOUT11 and an output clock signal COUT11, and the output signal OUT12 may include an output data signal DOUT12 and an output clock signal COUT12. The output signal OUT13 may include an output data signal DOUT13 and an output clock signal COUT13, and the output signal OUT14 may include an output data signal DOUT14 and an output clock signal COUT14. there is. Note that the number of clock edges corresponding to one packet is not limited to that shown in FIG. 4. Hereinafter, FIG. 4 will be explained with reference to FIG. 2 .

Referring to FIG. 4, the LED driving device 211 may sequentially receive the first to fourth packets PKT1 to PKT4 at time t41. The LED driving device 211 may detect the first packet PKT1 from the input data signal DIN based on the input clock signal CIN and identify dimming information in the first packet PKT1. The LED driving device 211 may generate the output data signal DOUT11 based on the input data signal DIN. The LED driving device 211 may remove (or disable) the first packet (PKT) from the output data signal (DOUT11) while adding status information to the second packet (PKT2) of the input data signal (DIN). A second packet (PKT2') can be generated. The LED driving device 211 may generate an output data signal (DOUT11) and an output clock signal (COUT11) so that the second packet and the clock edge are synchronized at time t42.

At time t42, the LED driving device 212 may receive the second packet PKT2' and identify dimming information from the second packet PKT2'. In addition, the LED driving device 212 may remove the second packet (PKT2') from the output data signal (OUT12), and the status information and self of the LED driving device 211 included in the second packet (PKT2'). A third packet (PKT3') including status information can be generated from the third packet (PKT3).

At time t43, the LED driving device 213 may receive the third packet PKT3' and identify dimming information from the third packet PKT3'. In addition, the LED driving device 213 may remove the third packet (PKT3') from the output data signal (OUT13), and the states of the LED driving devices (211 and 212) included in the third packet (PKT3') A fourth packet (PKT4') including information and its own status information can be generated from the fourth packet (PKT4).

At time t44, the LED driving device 214 may receive the fourth packet PK43' and identify dimming information from the fourth packet PKT4'. In addition, the LED driving device 214 may remove the fourth packet (PKT4') from the output data signal (OUT14), and the states of the LED driving devices (211 to 213) included in the fourth packet (PKT4') A fifth packet (PKT5) containing information and its own status information can be generated. In some embodiments, differently from what is shown in FIG. 4, the output clock signal COUT14 included in the output signal OUT14 may not vibrate due to the LED driving device 214 being set to the third mode.

5A and 5B are timing diagrams showing signals according to example embodiments of the present disclosure. For example, the timing diagram in FIG. 5A shows the input synchronization signal (SIN), the first output synchronization signal (SOUT1), and the second output synchronization signal (SOUT2) in the LED driving device set to the first mode, and the timing diagram in FIG. 5B The figure shows an input synchronization signal (SIN) and a first output synchronization signal (SOUT1) in the LED driving device set to the second mode. As described above with reference to FIG. 3, the LED driving devices 211, 221, 231, and 241 included in the first column in the driver array of FIG. 2 may be set to the first mode, and the LEDs included in the last column may be set to the first mode. The driving devices 214, 224, 234, and 244 may be set to the second mode, and the remaining LED driving devices (212, 213, 222, 223, 232, 233, 242, and 243) may be set to the third mode. It can be. In some embodiments, the LED driving device set to the third mode may generate the first output synchronization signal SOUT1 in the same way as the second mode. Hereinafter, FIGS. 5A and 5B will be explained with reference to FIG. 3 .

Referring to FIG. 5A, the input synchronization signal (SIN) may be activated every period (T _SYNC ). The period (T _SYNC ) may be the same as the period in which the vertical synchronization signal (VSYNC) is activated. The LED driving device 300 (or controller 320) set to the first mode may generate a first output synchronization signal (SOUT1) delayed by the first delay (D1) from the input synchronization signal (SIN), and A second output synchronization signal SOUT2 delayed by the second delay D2 may be generated from the synchronization signal SIB. As shown in FIG. 5A, the second delay (D2) may be greater than the first delay (D1) (D2>D1), and accordingly, the LED driving devices can sequentially update the LED driving currents on a row-by-row basis. . In some embodiments, the second delay (D2) may be equal to the first delay (D1).

Referring to FIG. 5B, the input synchronization signal (SIN) may be activated every period (T _SYNC ). The LED driving device 300 (or the controller 320) set to the second mode may generate a first output synchronization signal (SOUT1) that is not delayed from the input synchronization signal (SIN). Accordingly, LED driving devices included in the same row can update LED driving currents simultaneously.

FIG. 6 is a diagram illustrating an LED driving device 600 according to an exemplary embodiment of the present disclosure. For example, Figure 6 shows an LED driving device 600 implemented in a semiconductor package. The LED driving device 600 may be manufactured by a semiconductor process and may be mounted on a substrate, such as a printed circuit board (PCB).

Referring to FIG. 6, the LED driving device 600 may include a plurality of pins, and the pins may be electrically connected to a pattern included in the substrate. As shown in FIG. 6, the LED driving device 600 has a first pin group (G1) and a second pin group (G2) facing each other in the X-axis direction (in this specification, may be referred to as the first direction). ) and may include a third fin group G3 and a fourth fin group G4 facing each other in the Y-axis direction (in this specification, may be referred to as the second direction).

The first pin group (G1) includes input pins that respectively receive an input synchronization signal (SIN), an input data signal (DIN), and an input clock signal (CIN), and an output pin that outputs a second output synchronization signal (SOUT2). can do. The second pin group G2 may include output pins that respectively output a first output synchronization signal (SOUT1), an output data signal (DOUT), and an output clock signal (COUT). The third pin group G3 may include pins that respectively draw the first to fourth LED currents (I _LED1 to I _LED4 ). The fourth pin group G4 may include pins that respectively receive a positive supply voltage (VDD), a ground potential (GND), and an input mode signal (MIN).

If the LED driving device 600 operates as described above with reference to the drawings and includes pins as shown in FIG. 6, a backlight unit including a plurality of LED driving devices, as will be described later with reference to FIG. 7. can have a simple structure and can provide low cost, high productivity and high reliability.

FIG. 7 is a diagram illustrating a backlight unit 700 according to an exemplary embodiment of the present disclosure. In FIG. 7 , for convenience of illustration, the backlight unit 700 is shown as including only the first to sixth LED driving devices 701 to 706, and the LEDs are omitted. Each of the first to sixth LED driving devices 701 to 706 may have the same structure as the LED driving device 600 of FIG. 6.

Referring to FIG. 7 , the backlight unit 700 may include a substrate 710, and the first to sixth LED driving devices 701 to 706 may be mounted on the substrate 710. The substrate 710 may include an LED driving device and a pattern for connecting the LEDs. For example, as shown in FIG. 7, the substrate 710 may include a first pattern (P1), and the first pattern (P1) includes a first LED driving device 701 and an LED (not shown). can be connected to The fourth LED driving current may flow through the first pattern (P1). The substrate 710 may include patterns connecting adjacent LED driving devices in a row of the driver array. For example, as shown in FIG. 7 , the substrate 710 may include second patterns P21 and P22, and the second patterns P21 and P22 may be connected to the first LED driving device 701. And it can be connected to the second LED driving device 702. A synchronization signal and a positive supply voltage (VDD) may be transmitted through the second patterns (P21 and P22), respectively. Substrate 710 may include a pattern commonly connected to the LED driving devices in a row of the driver array. For example, as shown in FIG. 7, the substrate 710 may include a third pattern (P3), and the third pattern (P3) is applied to the first to third LED driving devices 701 to 703. Can be connected in common. A ground potential (GND) may be commonly provided to the first to third LED driving devices 701 to 703 through the third pattern P3. The substrate 710 may include patterns connecting adjacent LED driving devices in a row of the driver array. For example, as shown in FIG. 7, the substrate 710 may include a fourth pattern (P4), and the fourth pattern (P4) includes the first LED driving device 701 and the fourth LED driving device. (704) can be connected. A delayed synchronization signal may be transmitted through the fourth pattern P4.

The substrate 710 may include a pattern for setting the mode of the LED driving device. As described above with reference to FIGS. 2 and 3, the first LED driving device 701 and the fourth LED driving device 704 may be set to the first mode, and the second LED driving device 702 and the fourth LED driving device 704 may be set to the first mode. The 5 LED driving device 705 may be set to the second mode, and the third LED driving device 703 and the 6th LED driving device 706 may be set to the third mode. In some embodiments, the LED driving device may be set to the first mode when a positive supply voltage (VDD) is applied to the pin that receives the input mode signal (MIN), and receives the input mode signal (MIN). If the pin that receives the input mode signal (MIN) is floated, it may be set to the second mode, and if the ground potential (GND) is applied to the pin that receives the input mode signal (MIN), it may be set to the third mode. To this end, as shown in FIG. 7, the substrate 710 may include fifth patterns P51 and P52, and the fifth patterns P51 and P52 are connected to the positive supply voltage VDD and ground. Each potential (GND) can be transmitted. It is noted that the setting of the mode is not limited to the voltage and floating state shown in Figure 7.

In the backlight unit 700, a positive supply voltage (VDD) and a ground potential (GND) may be provided from the +X-axis direction to the -X-axis direction. The ground potential (GND) can be provided by the third pattern (P3) commonly connected to the first to third LED driving devices (701 to 703), while the positive supply voltage (VDD) is provided via the chip. It can be. For example, the second LED driving device 702 receives a positive supply voltage (VDD) from the third LED driving device 703 through a pin in the +X axis direction among the two pins corresponding to the positive supply voltage (VDD). VDD) can be received, and the received positive supply voltage (VDD) can be output through the pin in the -X axis direction. The first LED driving device 701 may receive the positive supply voltage (VDD) from the second LED driving device 702 through the second pattern (P22). That is, the LED driving device may include a structure that internally electrically connects two pins corresponding to the positive supply voltage (VDD). Below, examples of a structure that electrically connects two pins will be described with reference to FIGS. 8A to 8C.

As shown in FIG. 7, the patterns included in the substrate 710 may not intersect each other and may be formed on one conductive layer. Accordingly, the productivity and reliability of the substrate 710 can be improved, and the cost of the substrate 710 can be reduced. This effect may become more noticeable as the area of the display device increases.

8A to 8C are diagrams showing examples of the internal structure of a semiconductor package according to example embodiments of the present disclosure. For example, FIGS. 8A to 8C show examples of a structure that electrically connects two pins corresponding to a positive supply voltage (VDD). As described above with reference to the drawings, the LED driving device may be implemented as a semiconductor package, and as described above with reference to FIG. 7, the semiconductor package electrically connects two pins corresponding to the positive supply voltage (VDD). It may include a connecting structure. Hereinafter, overlapping content in the description of FIGS. 8A to 8C will be omitted, and FIGS. 8A to 8C will be described with reference to FIGS. 6 and 7.

Referring to FIG. 8A, the LED driving device 800a includes a lead-frame land pattern 810, a chip (or die) 820, and a plurality of pin land patterns (P11 to P14, etc.) ) may include. A plurality of chips (or dies) may be formed on the wafer through a semiconductor process, and the chip 820 separated from the wafer may be seated on the lead-frame land pattern 810. The chip 820 may include externally exposed pads, and as shown in FIG. 8A, the pads may be connected to the pin land pattern by a bonding wire.

The pin land patterns may correspond to the pin arrangement as described above with reference to FIG. 6 . For example, the pin land patterns P11 to P14 may respectively correspond to the input synchronization signal (SIN), the input data signal (DIN), the input clock signal (CIN), and the second output synchronization signal (SOUT2). The pin land patterns P21 to P23 may respectively correspond to the first output synchronization signal SOUT1, the output data signal DOUT, and the output clock signal COUT. The pin land patterns P41 to P44 may respectively correspond to a positive supply voltage (VDD), an input mode signal (MIN), a ground potential (GND), and a positive supply voltage (VDD). The pin land patterns (P31 to P34) may respectively correspond to the first to fourth LEDs (LED1 to LED4).

The LED driving device 800a may include a bonding wire W8 connecting the pin land patterns P41 and P44 corresponding to the positive supply voltage VDD. Accordingly, the positive supply voltage (VDD) can be received by the LED driving device (800a) through the pin land pattern (P44), and the LED driving device (800a) through the bonding wire (W8) and the pin land pattern (P41). ) can be output outside of.

Referring to FIG. 8B, in the LED driving device 800b, the pin land patterns P41 and P44 corresponding to the positive supply voltage VDD may be electrically connected through the conductive pattern of the chip 820. For example, as shown in FIG. 8B, the pin land pattern P44 receiving the positive supply voltage (VDD) may be connected to the first pad of the chip 820 through a bonding wire, and the chip may be connected to the first pad of the chip 820. It may include a conductive pattern 821 connecting the pad and the second pad. The pin land pattern P41 may be connected to the second pad through a bonding wire and, as a result, may be electrically connected to the pin land pattern P44.

Referring to FIG. 8C , in the LED driving device 800c, the pin land patterns P41 and P44 corresponding to the positive supply voltage VDD may be electrically connected through the lead-frame land pattern 810. For example, as shown in FIG. 8C, the pin land patterns P41 and P44 may be connected to the lead-frame land pattern 810 and thus may be electrically connected. In some embodiments, the fin land patterns P41 and P44 and the lead-frame land pattern 810 may be integrally formed as one pattern.

As above, exemplary embodiments have been disclosed in the drawings and specification. Although embodiments have been described in this specification using specific terms, this is only used for the purpose of explaining the technical idea of the present disclosure and is not used to limit the meaning or scope of the present disclosure as set forth in the claims. . Therefore, those skilled in the art will understand that various modifications and other equivalent embodiments are possible therefrom. Therefore, the true technical protection scope of the present disclosure should be determined by the technical spirit of the attached patent claims.

Claims (14)

An LED driving device configured to generate light emitting diode (LED) driving currents based on input signals, comprising:
a first pin group and a second pin group facing each other in a first direction; and
A third fin group and a fourth fin group facing each other in a second direction perpendicular to the first direction,
The first pin group includes pins configured to receive the input signals,
The second pin group includes pins configured to output output signals generated based on the input signals to provide to an LED driving device adjacent in the first direction,
The third pin group includes pins configured to draw the LED driving currents from a plurality of LEDs,
The fourth pin group includes pins configured to receive supply voltages that provide power to the LED drive device,
The fourth pin group is,
a first pin and a second pin configured to be applied with a positive supply voltage; and
At least one third pin configured to apply a negative supply voltage,
The third pin is disposed between the first pin and the second pin in the fourth pin group,
The LED driving device further includes a conductive member electrically connecting the first pin and the second pin so that the positive supply voltage is received through the first pin and output through the second pin. Featured LED driving device. In claim 1,
The first pin group includes a first input pin configured to receive an input data signal including information about the magnitude of the LED driving current among the input signals,
The second pin group includes a first output pin configured to output an output data signal generated based on the input data signal among the output signals,
The first input pin and the first output pin are opposite to each other in the first direction. In claim 2,
The first pin group includes a second input pin configured to receive an input clock signal synchronized to the input data signal among the input signals,
The second pin group includes a second output pin configured to output an output clock signal generated based on the input clock signal among the output signals,
The second input pin and the second output pin are opposite to each other in the first direction. delete An LED driving device configured to generate light emitting diode (LED) driving currents based on input signals, comprising:
a first pin group and a second pin group facing each other in a first direction; and
A third fin group and a fourth fin group facing each other in a second direction perpendicular to the first direction,
The first pin group includes pins configured to receive the input signals,
The second pin group includes pins configured to output output signals generated based on the input signals to provide to an LED driving device adjacent in the first direction,
The third pin group includes pins configured to draw the LED driving currents from a plurality of LEDs,
The fourth pin group includes pins configured to receive supply voltages that provide power to the LED drive device,
The first pin group includes a third input pin configured to receive an input synchronization signal instructing update of the LED driving currents,
The second pin group includes a third output pin configured to output a first output synchronization signal generated based on the input synchronization signal among the output signals,
The third input pin and the third output pin face each other in the first direction,
The first pin group further includes a fourth output pin configured to output a second output synchronization signal generated based on the input synchronization signal to be provided to an LED driving device adjacent to the second direction,
The third input pin and the fourth output pin are arranged at the outermost part of the first pin group. delete delete In claim 1,
The conductive member is an LED driving device characterized in that it includes at least one of a bonding wire, a pattern of a wiring layer, and a lead-frame. In claim 1,
The fourth pin group further includes a fourth input pin configured to receive a mode signal for setting a mode of the LED driving device,
The LED driving device is configured to differently generate at least one of the output signals based on the mode. In claim 9,
The LED driving device is configured to identify the mode based on at least one of a voltage applied to the fourth input pin and an open state of the fourth input pin,
The fourth input pin is an LED driving device, characterized in that disposed between the first pin and the third pin in the fourth pin group. a plurality of LEDs (light emitting diodes);
a driver array including a plurality of LED driving devices each configured to drive at least one of the plurality of LEDs; and
Comprising a substrate on which the plurality of LEDs and the driver array are mounted,
The substrate is,
a plurality of first patterns connecting the driver array and the plurality of LEDs;
a plurality of second patterns connecting adjacent LED driving devices in each row of the driver array; and
Comprising a third pattern commonly connected to the LED driving devices in each row of the driver array,
The plurality of first patterns, the plurality of second patterns, and the third pattern are included in the same conductive layer of the substrate,
The plurality of second patterns are,
at least one second pattern configured to transmit at least one signal from the first LED driving device to a second LED driving device adjacent to the row direction; and
A display device comprising at least one second pattern configured to transfer a positive supply voltage from the second LED driving device to the first LED driving device. delete In claim 11,
The substrate further includes a plurality of fourth patterns connecting adjacent LED driving devices in each row of the driver array,
A display device, wherein the plurality of fourth patterns are included in the conductive layer. a plurality of LEDs (light emitting diodes);
a driver array including a plurality of LED driving devices each configured to drive at least one of the plurality of LEDs; and
Comprising a substrate on which the plurality of LEDs and the driver array are mounted,
The substrate is,
a plurality of first patterns connecting the driver array and the plurality of LEDs;
a plurality of second patterns connecting adjacent LED driving devices in each row of the driver array; and
Comprising a third pattern commonly connected to the LED driving devices in each row of the driver array,
The plurality of first patterns, the plurality of second patterns, and the third pattern are included in the same conductive layer of the substrate,
Each of the plurality of LED driving devices includes a mode input pin configured to receive a mode signal for setting a mode,
The plurality of LED driving devices,
a first group included in a first outermost column of the driver array;
a second group included in the second outermost column of the driver array; and
Including a third group excluding the first group and the second group,
The substrate is arranged such that the first group of mode input pins, the second group of mode input pins, and the third group of mode input pins mutually exclusively correspond to a positive supply voltage, a negative supply voltage, and an open state. Further comprising a plurality of fifth patterns,
A display device, wherein the plurality of fifth patterns are included in the conductive layer.

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