LED display driving circuit and LED display device including same

Abstract

An LED display driving circuit and an LED display device including the same are provided. The LED display driving circuit includes a channel driving circuit configured to provide a channel current to a plurality of channel lines according to a pulse width modulation (PWM) control signal; a scan driving circuit including a plurality of scan switches connected to the plurality of scan lines and selectively turned on or off according to a scan signal to select a scan line connected to an LED to emit light, and a plurality of pre-charge switches connected to the plurality of scan lines and operated complementarily with the scan switches; and a data controller configured to generate a PWM control signal, a scan signal, and a pre-charge control signal, and when a short-circuited LED of the plurality of LEDs is detected, when a scan switch of a target scan line to which the short-circuited LED is connected is turned off, maintain the target scan line in a floating state by turning off a pre-charge switch connected to the target scan line.

Description

Technical Field

[0001] The present disclosure relates to a display device, and more particularly, to a light emitting diode (LED) display. Background Art

[0002] With the advancement of informatization, various display devices that can visualize information are being developed. Liquid crystal display (LCD) devices, organic light-emitting diode (OLED) display devices, and plasma display panel (PDP) display devices are examples of display devices that have already been developed or are currently under development. These display devices are evolving to be capable of displaying high-resolution images.

[0003] However, while display devices have the advantage of high resolution, they are difficult to scale up. For example, large OLED display devices developed to date have sizes of 80 inches (about 2 meters) or 100 inches (about 2.5 meters), making them unsuitable for manufacturing large displays exceeding 10 meters in width.

[0004] As a solution to this scaling issue, interest in LED displays has been growing recently. In LED display technology, a desired number of modular LED pixels can be arranged to form a single large panel. Alternatively, a desired number of unit panels composed of multiple LED pixels can be arranged to form a single large panel structure. This makes it easier to implement large-scale displays by expanding and arranging LED pixels as needed.

[0005] LED display devices have the advantage of being able to not only expand but also diversify panel sizes. LED display device technology allows horizontal and vertical sizes to be adjusted in various ways according to appropriate arrangement of LED pixels.

[0006] In an LED display device, when the LED of a specific pixel is short-circuited, there is a problem that the overall brightness of normal LEDs connected to the same channel line as the short-circuited LED may become brighter (bright line) or darker (dark line), resulting in image quality failure.

[0007] As a method of solving this problem, it may be considered to detect and repair the short-circuited LED or replace the short-circuited LED with a normal LED, but there is a problem in that repairing or replacing the short-circuited LED is expensive and time-consuming. Summary of the Invention

[0008] Therefore, a light emitting diode (LED) display driving circuit that can reduce line failure caused by a short-circuited LED and an LED display device including the same are provided.

[0009] Also provided are an LED display driving circuit capable of compensating the brightness of a normal LED connected to the same channel line as the short-circuited LED, and an LED display device including the LED display driving circuit.

[0010] According to one aspect of the present disclosure, an LED display driver is provided, the LED display driver comprising: a channel driver circuit configured to supply a channel current to each of a plurality of channel lines according to a pulse width modulation (PWM) control signal and to cause a plurality of LEDs connected to each of the channel lines to emit light; a scan driver circuit comprising a plurality of scan switches and a plurality of precharge switches, the plurality of scan switches being connected to the plurality of scan lines and selectively turned on or off according to scan signals to select a scan line connected to an LED to be emitted light, the plurality of precharge switches being connected to the plurality of scan lines and configured to operate complementarily with the scan switches according to a precharge control signal and being turned on when each of the scan switches is turned off to supply a precharge voltage to the corresponding scan line; and a data controller configured to generate a PWM control signal, a scan signal, and a precharge control signal, and, upon detecting a short-circuited LED among the plurality of LEDs, maintain the target scan line in a floating state by turning off the precharge switch connected to the target scan line when the scan switch of the target scan line to which the short-circuited LED is connected is turned off.

[0011] According to another aspect of the present disclosure, an LED display device is provided, the LED display device comprising: a display panel including a plurality of LEDs arranged in a plurality of sub-pixels where a plurality of channel lines and a plurality of scan lines intersect; and an LED display drive circuit configured to provide channel currents to the plurality of LEDs and cause the plurality of LEDs to emit light, wherein the LED display drive circuit comprises: a channel drive circuit configured to provide the channel current through each channel line according to a pulse width modulation (PWM) control signal; a scan drive circuit comprising a plurality of scan switches and a plurality of pre-charge switches, the plurality of scan switches being connected to the plurality of scan lines. The data controller includes a plurality of pre-charge switches connected to the plurality of scan lines and configured to operate complementarily with the scan switches according to a pre-charge control signal, and to be turned on when each of the scan switches is off to provide a pre-charge voltage to the corresponding scan line; and a data controller configured to generate a PWM control signal, a scan signal and a pre-charge control signal, and when a short-circuited LED among the plurality of LEDs is detected, when the scan switch of the target scan line to which the short-circuited LED is connected is turned off, the target scan line is kept in a floating state by turning off the pre-charge switch connected to the target scan line. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this application. The drawings illustrate embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure. In the drawings:

[0013] Figure 1 is a diagram showing a configuration of a light emitting diode (LED) display device according to one embodiment of the present disclosure;

[0014] Figure 2 is a schematic diagram showing the configuration of an LED display driving circuit according to one embodiment of the present disclosure;

[0015] Figure 3 is a diagram showing a waveform of a scan signal in an LED display device according to an embodiment of the present disclosure;

[0016] Figure 4 It shows Figure 3 A timing diagram showing the operating timing of some components of a normal LED display device;

[0017] Figure 5A and Figure 5B is a diagram showing a line defect phenomenon caused by a short-circuited LED;

[0018] Figure 6A is a diagram showing a phenomenon in which all LEDs connected to the first channel line to which the short-circuited LED is connected light up (bright line) when the level of the precharge voltage is higher than the level of the first channel voltage of the first channel line;

[0019] Figure 6B is a diagram showing a phenomenon in which all LEDs connected to the first channel line to which the short-circuited LED is connected dim (dark line) when the level of the precharge voltage is lower than the level of the first channel voltage of the first channel line;

[0020] Figure 7 is a timing diagram illustrating the operational timing of some components of an LED display device including a short-circuited LED;

[0021] Figure 8A is a waveform diagram conceptually illustrating a method for calculating a brightness compensation amount by a brightness compensation circuit according to one embodiment of the present disclosure;

[0022] Figure 8B is a block diagram showing a configuration of a brightness compensation circuit according to one embodiment of the present disclosure;

[0023] Figure 9A is a waveform diagram conceptually illustrating a method for calculating a brightness compensation amount by a brightness compensation circuit according to another embodiment of the present disclosure;

[0024] Figure 9B is a block diagram showing a configuration of a brightness compensation circuit according to another embodiment of the present disclosure; and

[0025] Figure 10A and Figure 10B This is a diagram showing a dot darkening phenomenon in which only a short-circuited LED does not emit light. DETAILED DESCRIPTION

[0026] The advantages and features of the present disclosure and their implementation methods will be illustrated by the following exemplary embodiments described with reference to the accompanying drawings. However, the present disclosure can be implemented in different forms and should not be considered as limited to the exemplary embodiments described herein. On the contrary, these exemplary embodiments are provided so that the present disclosure will be thorough and complete and will fully convey the scope of the present disclosure to those skilled in the art. Furthermore, the present disclosure is limited only by the scope of the claims.

[0027] Throughout this disclosure, the same reference numerals denote substantially the same elements. In the following description, when it is determined that a detailed description of related known functions or configurations would unnecessarily obscure the key points of this disclosure, such detailed descriptions will be omitted. In addition, the names of the elements used in the following description are examples and may differ from the names of the actual products corresponding to the elements.

[0028] In case where “including,” “having,” and “comprising” described in the present disclosure are used, another part may be added. Unless otherwise indicated, terms in the singular form may include plural forms.

[0029] When interpreting an element, the element is interpreted as including a range of error although there is no explicit description.

[0030] It should be understood that although the terms "first," "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. In addition, the first element mentioned below may be referred to as the second element without departing from the scope of this disclosure.

[0031] The term "at least one" should be understood to include any and all combinations of one or more of the associated listed items. For example, "at least one of the first, second, and third items" means each of the first, second, and third items, as well as all combinations of two or more of the first, second, and third items.

[0032] The features of the various exemplary embodiments of the present disclosure may be coupled or combined with each other in part or in whole, and may interoperate or combine with each other in various ways and be technically driven as will be fully understood by those skilled in the art. The exemplary embodiments of the present disclosure may be performed independently of each other, or may be performed together in a mutually dependent relationship.

[0033] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0034] Figure 1 is a diagram illustrating a configuration of a light emitting diode (LED) display device according to one embodiment of the present disclosure.

[0035] like Figure 1 As shown, the LED display device 100 according to one embodiment of the present disclosure includes a display panel 110 and an LED display driving circuit 120 .

[0036] The display panel 110 may include a plurality of pixels P. The plurality of pixels P may be arranged along a first direction (eg, Figure 1 horizontal direction) and a second direction (e.g., Figure 1 The pixels P may be arranged in a matrix (in a vertical direction). At least one LED may be provided in each pixel P, and the brightness of the pixel P may be determined according to the brightness of the LED. That is, the display panel 110 may be an LED display panel.

[0037] Each pixel P may include multiple sub-pixels. For example, each pixel P may include three sub-pixels. Each pixel P may include a red sub-pixel that emits red light, a green sub-pixel that emits green light, and a blue sub-pixel that emits blue light. An LED may be provided in each sub-pixel.

[0038] A plurality of channel lines CL1 to CLm and a plurality of scan lines SL1 to SLn are provided in the display panel 110. Each subpixel may be provided in a region where a channel line and a scan line intersect. That is, an LED provided in each subpixel may be electrically connected to one of the channel lines CL1 to CLm and one of the scan lines SL1 to SLn.

[0039] The channel lines CL1 to CLm can connect one side of the sub-pixel in the second direction, and the scan lines SL1 to SLn can connect the other side of the sub-pixel in the first direction. For example, the anode of the LED set in the sub-pixel can be electrically connected to the channel lines CL1 to CLm, and the cathode of the LED can be electrically connected to the scan lines SL1 to SLn. Because the cathodes of the LEDs are connected in common, Figure 1 The example shown is also referred to as a common cathode structure, but the present disclosure is not limited to this structure.

[0040] The LED display driving circuit 120 provides channel current to the plurality of LEDs included in the display panel 110 so that the plurality of LEDs emit light. In one embodiment, the LEDs may be driven in a pulse width modulation (PWM) manner, and the LED display driving circuit 120 may perform PWM control on each pixel P based on image data DATA received from an external component.

[0041] The grayscale value of each pixel P may be included in the image data DATA. The LED display driving circuit 120 may receive the image data DATA from an external component according to a clock CLK and obtain the grayscale value for each pixel P from the image data DATA.

[0042] The LED display driver circuit 120 can determine the PWM control time for the LEDs provided in each sub-pixel based on the grayscale value and perform PWM control on each LED. As described above, when driving LEDs in a PWM manner, the brightness of the LEDs can be determined based on the ratio of the on-time to the PWM control time. Therefore, the LED display driver circuit 120 can control the brightness of the LEDs by controlling the on-time within the PWM control time.

[0043] Specifically, the brightness of the LED in each subpixel can be determined by the amount of channel current supplied through the channel line connected to the corresponding LED among the channel lines CL1 to CLm. When the LED is turned on by the channel current, a forward voltage can be applied to the LED. When the product of the forward voltage and the channel current accumulates during the on-time within the PWM control time, the amount of driving power supplied to the LED is obtained, and the brightness of the LED can be determined based on the driving power amount.

[0044] In the following, reference will be made to Figure 2 An LED display driving circuit according to the present disclosure is described.

[0045] Figure 2 Schematic diagram showing the configuration of an LED display driving circuit according to an embodiment of the present disclosure. Figure 2 , the display panel 110 is shown to include three scan lines SL1 to SL3 , three channel lines CL1 to CL3 , and nine LEDs.

[0046] like Figure 2 As shown, the LED display driving circuit 120 may include a scan driving circuit 122 , a channel driving circuit 124 and a data controller 126 .

[0047] The scan driving circuit 122 is connected to the plurality of scan lines SL1 to SL3 and drives the scan lines SL1 to SL3 according to the scan signals SCAN_1 to SCAN_3 provided from the data controller 126. Figure 2 As shown, the scan driving circuit 122 includes a plurality of scan switches SW1 to SW3.

[0048] exist Figure 2 In the embodiment, since the display panel 110 is shown as including only three scan lines SL1 to SL3, the scan driving circuit 122 is shown as including only three scan switches SW1 to SW3. However, when the display panel 110 includes n scan lines SL1 to SLn, the scan driving circuit 122 may include n scan switches SW1 to SWn.

[0049] A plurality of scan switches SW1 to SW3 are connected to scan lines SL1 to SL3, respectively. The plurality of scan switches SW1 to SW3 are selectively turned on or off according to scan signals SCAN_1 to SCAN_3 provided from the data controller 126. When the corresponding scan switches SW1 to SW3 are turned on according to the supply of the scan signals SCAN_1 to SCAN_3, the scan lines SL1 to SL3 may each be connected to a low voltage portion of the LED display device 100, for example, a ground (GND) level.

[0050] Since the scan switches SW1 to SW3 are selectively turned on or off according to the scan signals SCAN_1 to SCAN_3 , the scan lines SL1 to SL3 to which the channel current is supplied among the plurality of scan lines SL1 to SL3 are determined.

[0051] In the above example, although the scan switches SW1 to SW3 are described as being formed within the LED display driving circuit 120 , in another example, the scan switches SW1 to SW3 may be formed in the display panel 110 or on a separate substrate.

[0052] Figure 3 is a diagram illustrating a waveform of a scan signal in an LED display device according to an embodiment of the present disclosure.

[0053] Reference Figure 1 and Figure 3 , one frame is formed by N segments (N is a natural number), and scan signals SCAN_1 to SCAN_n can be sequentially provided to scan switches SW1 to SWn for each segment unit. Here, a frame can be each image constituting an image, and one segment can be a unit for performing a scan operation for one cycle.

[0054] According to the scan signals SCAN_1 to SCAN_n, the first to nth scan lines SL1 to SLn may be sequentially driven. However, according to an example, the order of the scan operations may not be in the order from the first to nth scan lines SL1 to SLn. For example, the order of the scan operations may be determined by considering printed circuit board (PCB) wiring.

[0055] In one embodiment, when each subpixel is PWM-controlled once per frame, the grayscale value can be directly converted into a PWM control value, and each subpixel can be controlled based on the PWM control value. Alternatively, when a frame is divided into N segments, the grayscale value is divided into N segments and allocated, and the PWM control value can be determined based on the grayscale value allocated to each segment. In this case, each subpixel can be controlled based on the PWM control value converted based on the grayscale value allocated to each segment.

[0056] Refer again Figure 2 , the scan driving circuit 122 according to the present disclosure may further include a pre-charge voltage source 210 and pre-charge switches PSW1 to PSW3. Figure 2 In the embodiment, since the display panel 110 is shown as including only three scan lines SL1 to SL3, the scan driving circuit 122 is shown as including only three pre-charging switches PSW1 to PSW3. However, when the display panel 110 includes n scan lines SL1 to SLn, the scan driving circuit 122 may include n pre-charging switches PSW1 to PSWn.

[0057] The precharge voltage source 210 supplies a precharge voltage Vprecharge to the scan lines SL1 to SL3 whose scan operations have ended, to prevent a ghost phenomenon in which the LEDs connected to the scan lines SL1 to SL3 whose scan operations have ended emit light. Precharge is an operation that charges the capacitors C1 to C3 connected to the scan lines SL1 to SL3 whose scan operations have ended before the scan operations of the other scan lines SL1 to SL3 begin. Precharge can be performed between the time when a scan operation ends and the time when the next scan operation begins.

[0058] Since the precharge voltage source 210 precharges the capacitors C1 to C3, the voltage of the capacitors C1 to C3 can be increased. Therefore, the LEDs connected to the capacitors C1 to C3 remain in a reverse bias state, so no current can flow in the LEDs. Therefore, the LEDs connected to the capacitors C1 to C3 of the scan lines SL1 to SL3 whose scan operation has ended cannot emit light.

[0059] In this case, the capacitors C1 to C3 may be parasitic capacitors of the LED. The capacitors C1 to C3 may be capacitors that form electrostatic capacitance within the LED display device 100 according to the operation of the LED display driving circuit 120 or the display panel 110. The capacitors C1 to C3 may be virtual capacitors rather than physical capacitors.

[0060] Capacitors C1 to C3 form electrostatic capacitance between the LEDs and the scan switches SW1 to SW3. Figure 2 2 and 3. The display panel 110 is shown to include three capacitors C1 to C3, but when the display panel 110 includes n scan lines SL1 to SLn, the display panel 110 may include n capacitors C1 to Cn.

[0061] The precharge switches PSW1 to PSW3 are selectively turned on or off by precharge control signals PCS_1 to PCS_3 generated by the data controller 126, thereby providing a precharge voltage to the scan lines SL1 to SL3. When the precharge switches PSW1 to PSW3 are turned on by the precharge control signals PCS_1 to PCS_3, the corresponding scan lines SL1 to SL3 are connected to the precharge voltage power supply 210, thereby charging the capacitors C1 to C3 of the corresponding scan lines SL1 to SL3 with the precharge voltage.

[0062] In the following, reference will be made to Figure 4 A scan operation and a precharge operation performed in the first scan line SL1 are briefly described.

[0063] Figure 4 It shows Figure 3The timing diagram shown shows the operating timing of each component of the LED device.

[0064] like Figure 4 As shown in FIG. 1 , the first scan switch SW1 is turned on according to the first scan signal SCAN_1, and thus the first scan line SL1 is connected to ground. In this case, the first precharge switch PSW1 is turned off according to the first precharge control signal PCS_1. Therefore, the voltage of the first capacitor C1 provided on the first scan line SL1 can decrease from the time the first scan switch SW1 is turned on, and then can be maintained at a minimum value until the time the first scan switch SW1 is turned off.

[0065] Thereafter, the first scan switch SW1 is turned off in accordance with the first scan signal SCAN_1, so that the first scan line SL1 is maintained at the scan-off level, and after a predetermined time has passed, the second scan switch SW2 is turned on in accordance with the second scan signal SCAN_2. In this case, the second scan switch SW2 is turned on after a predetermined time has passed from the time point when the first scan switch SW1 was turned off in order to prevent the LEDs connected to the first scan line SL1 and the second scan line SL2 from emitting light simultaneously due to overlapping operations of the first scan line SL1 and the second scan line SL2.

[0066] At the same time, the first scan switch SW1 is turned off, and the first precharge switch PSW1 is simultaneously turned on by the first precharge control signal PCS_1. As a result, the first capacitor C1 connected to the first scan line SL1 is charged with a precharge voltage. As the charge of the first capacitor C1 increases, the voltage of the first capacitor C1 may increase. The voltage of the first capacitor C1 may reach a maximum value before the second scan switch SW2 is turned on, and may then remain at the maximum value until the first scan line SL1 is driven again.

[0067] That is, the first capacitor C1 can be precharged between the time point when the first scan switch SW1 is turned off and the time point when the second scan switch SW2 is turned on, and as the first capacitor C1 is precharged, the voltage of the first capacitor C1 maintains a maximum value, so the LED connected to the first capacitor C1 maintains a reverse bias state, thereby preventing the ghost phenomenon.

[0068] Thereafter, the second scan switch SW2 is turned on according to the second scan signal SCAN_2, thereby connecting the second scan line SL2 to ground. In this case, the second precharge switch PSW2 is turned off according to the second precharge control signal PCS_2. Therefore, the voltage of the second capacitor C2 provided on the second scan line SL2 can decrease from the time when the second scan switch SW2 is turned on, and then can be maintained at a minimum value until the time when the second scan switch SW2 is turned off.

[0069] Thereafter, the second scan switch SW2 is turned off according to the second scan signal SCAN_2 , so the second scan line SL2 is maintained at a scan-off level, and after a predetermined time elapses, the third scan switch SW3 is turned on according to the third scan signal SCAN_3 .

[0070] At the same time, the second scan switch SW2 is turned off, and the second precharge switch PSW2 is simultaneously turned on by the second precharge control signal PCS_2, so that the second capacitor C2 connected to the second scan line SL2 is charged with the precharge voltage. As the amount of charge in the second capacitor C2 increases, the voltage of the second capacitor C2 may increase. The voltage of the second capacitor C2 may reach a maximum value before the third scan switch SW3 is turned on, and may then be maintained at the maximum value until the second scan line SL2 is driven again.

[0071] That is, the second capacitor C2 can be precharged between the time point when the second scan switch SW2 is turned off and the time point when the third scan switch SW3 is turned on, and as the second capacitor C2 is precharged, the voltage of the second capacitor C2 maintains a maximum value, so the LED connected to the second capacitor C2 maintains a reverse bias state, thereby preventing the ghost phenomenon.

[0072] Thereafter, the third scan switch SW3 is turned on according to the third scan signal SCAN_3, thereby connecting the third scan line SL3 to ground. In this case, the third precharge switch PSW3 is turned off according to the third precharge control signal PCS_3. Therefore, the voltage of the third capacitor C3 provided on the third scan line SL3 can decrease from the time when the third scan switch SW3 is turned on, and then can be maintained at a minimum value until the time when the third scan switch SW3 is turned off.

[0073] Thereafter, the third scan switch SW3 is turned off according to the third scan signal SCAN_3 , so the third scan line SL3 is maintained at a scan-off level, and after a predetermined time elapses, the fourth scan switch SW4 is turned on according to the fourth scan signal SCAN_4 .

[0074] At the same time, the third scan switch SW3 is turned off, and the third precharge switch PSW3 is simultaneously turned on by the third precharge control signal PCS_3. As a result, the third capacitor C3 connected to the third scan line SL3 is charged with a precharge voltage. As the charge of the third capacitor C3 increases, the voltage of the third capacitor C3 may increase. The voltage of the third capacitor C3 may reach a maximum value before the fourth scan switch SW4 is turned on, and may then remain at the maximum value until the third scan line SL3 is driven again.

[0075] That is, the third capacitor C3 can be precharged between the time point when the third scan switch SW3 is turned off and the time point when the fourth scan switch SW4 is turned on, and as the third capacitor C3 is precharged, the voltage of the third capacitor C3 maintains a maximum value, so the LED connected to the third capacitor C3 maintains a reverse bias state, thereby preventing the ghost phenomenon.

[0076] Refer again Figure 2 The channel driving circuit 124 is connected to a plurality of channel lines CL1 to CLm and provides a channel current to the sub-pixels connected to each of the channel lines CL1 to CLm through each of the channel lines CL1 to CLm. In this case, the channel driving circuit 124 can control the amount of channel current provided to the LED connected to each of the channel lines CL1 to CLm according to the PWM control signals PWM_1 to PWM_m provided by the data controller 126.

[0077] To this end, the channel driving circuit 124 may include channel current sources 220_1 to 220 — m and PWM switches 230_1 to 230 — m for the channel lines CL1 to CLm.

[0078] For ease of description, Figure 2 1 to 3. FIGURE 1 shows only three channel lines CL1 to CL3 included in the display panel 110, and thus the channel driver circuit 124 is shown as including first to third channel current sources 220_1 to 220_3 and first to third PWM switches 230_1 to 230_3. However, when the display panel 110 includes m channel lines CL1 to CLm, the channel driver circuit 124 may include m channel current sources 220_1 to 220_m and m PWM switches 230_1 to 230_m.

[0079] The operations of the first to third channel current sources 220_1 to 220_3 are identical to each other, and the operations of the first to third PWM switches 230_1 to 230_m are also identical to each other, so only the operations of the first channel current source 220_1 and the first PWM switch 230_1 will be described below.

[0080] The first channel current source 220_1 can generate a channel current using an externally provided LED driving voltage VLED. The channel current generated by the first channel current source 220_1 can be provided to the LED connected to the first channel line CL1 via the first channel line CL1. The first channel current source 220_1 can be connected in series between a power line of the LED driving voltage VLED and the first PWM switch 230_1.

[0081] The first PWM switch 230_1 is selectively turned on or off according to a first PWM control signal PWM_1 received from the data controller 126, thereby controlling the time when a channel current is supplied through the first channel line CL1. The amount of channel current supplied through the first channel line CL1 can be determined by the time when the first PWM switch 230_1 is turned on. Therefore, the brightness of the LED connected to the first channel line CL1 can be determined.

[0082] like Figure 4 As shown, the first PWM control signal PWM_1 may include an ON period and an OFF period (corresponding to a period other than the ON period). The first PWM switch 230_1 is turned on during the ON period of the first PWM control signal PWM_1 to supply the channel current provided by the first channel current source 220_1 to the first channel line CL1, and is turned off during the OFF period of the first PWM control signal PWM_1 to block the channel current provided by the first channel current source 220_1 from being supplied to the first channel line CL1.

[0083] The first PWM switch 230_1 may be connected in series between the LED and the first channel current source 210_1 .

[0084] In one embodiment, Figure 4 As shown, while the scan lines SL1 to SL3 are driven, when the first PWM switch 203_1 is turned on and thus supplies a channel current to the first channel line CL1, the first channel voltage V_CH1 applied to the first channel line CL1 may increase from a level of a reference voltage VOFF that is higher than a level of the ground GND, and when the first PWM switch 203_1 is turned off and stops supplying the channel current, the first channel voltage V_CH1 may decrease again to the level of the reference voltage VOFF.

[0085] In the present disclosure, the reason why the first channel voltage V_CH1 applied to the first channel line CL1 is maintained at a level of the reference voltage VOFF that is higher than a level of the ground GND level when driving each of the scan lines SL1 to SL3 is to reduce the time it takes for the first channel voltage V_CH1 of the first channel line CL1 to increase to a maximum value according to the supply of the channel current.

[0086] For this reason, Figure 2 As shown, the channel driving circuit 124 according to the present disclosure may further include a first reference voltage generating circuit 240_1 for generating a reference voltage VOFF and a first reference voltage applying switch 250_1 for selectively applying the reference voltage VOFF to the first channel line CL1. In this case, the first reference voltage applying switch 250_1 may be selectively turned on or off according to a first reference voltage applying signal RVS_1 transmitted from the data controller 126.

[0087] For ease of description, Figure 2 1 to 3. FIG. 4 shows only three channel lines CL1 to CL3 included in the display panel 110, and thus the channel driving circuit 124 is shown as including first to third reference voltage generating circuits 240_1 to 240_3 and first to third reference voltage applying switches 250_1 to 250_3. However, when the display panel 110 includes m channel lines CL1 to CLm, the channel driving circuit 124 may include m reference voltage generating circuits 240_1 to 240_m and m reference voltage applying switches 250_1 to 250_m.

[0088] The data controller 216 may generate scan signals SCAN_1 to SCAN_n, PWM control signals PWM_1 to PWM_m, precharge control signals PCS_1 to PCS_n, and reference voltage application signals RVS_1 to RVS_m. The data controller 216 applies the scan signals SCAN_1 to SCAN_n and precharge control signals PCS_1 to PCS_n to the scan driving circuit 122, and applies the PWM control signals PWM_1 to PWM_m and reference voltage application signals RVS_1 to RVS_m to the channel driving circuit 124.

[0089] In one embodiment, the data controller 216 can adjust the length of the ON period of the PWM control signals PWM_1 to PWM_m based on the internal clock GCLK. The data controller 216 can adjust the length of the ON period of the PWM control signals PWM_1 to PWM_m by matching one unit of grayscale value with one period of the internal clock GCLK. For example, when the grayscale value is 1, the length of the ON period of the PWM control signals PWM_1 to PWM_m can be equal to one period of the internal clock GCLK.

[0090] In the LED display device 100, when any one of the plurality of LEDs included in the display panel 110 is short-circuited, as shown in FIG. Figure 5A and Figure 5B As shown, a line defect phenomenon may occur in which the brightness of all LEDs connected to the corresponding channel line becomes brighter or darker.

[0091] Specifically, if Figure 6AAs shown, when the first LED L11 connected to the first channel line CL1 and the first scan line SL1 is short-circuited and the level of the pre-charge voltage is higher than the first channel voltage V_CH1 of the first channel line CL1, and when the second LED L12 to the nth LED L1n connected to the first channel line CL1 emit light, since the pre-charge voltage provided through the first scan line SL is also provided to the second LED L12 to the nth LED L1n through the short-circuited first LED L11, a phenomenon occurs in which all LEDs connected to the first channel line CL1 become bright (bright line).

[0092] As another example, Figure 6B As shown, when the first LED L11 connected to the first channel line CL1 and the first scan line SL1 is short-circuited and the level of the pre-charge voltage is lower than the first channel voltage V_CH1 of the first channel line CL1, and when the second LED L12 to the nth LED L1n connected to the first channel line CL1 emit light, since the channel current that should be provided through the first channel line CL1 is discharged through the short-circuited first LED L11, a phenomenon occurs in which all LEDs connected to the first channel line CL1 become dim (dark line).

[0093] Therefore, in order to reduce the image defects caused by the short-circuited LED, the LED display driving circuit 120 according to the present disclosure may further include short-circuit detection circuits 260_1 to 260_3, such as Figure 2 shown.

[0094] exist Figure 2 In the example, short-circuit detection circuits 260_1 to 260_3 are shown as being provided for each channel line CL1 to CL3, but this is merely an example. A single short-circuit detection circuit can be connected to all channel lines CL1 to CL3 to detect a shorted LED for each of the channel lines CL1 to CL3. In this example, the short-circuit detection circuit can be included in the channel driver circuit 124 or implemented in a component separate from the channel driver circuit 24.

[0095] The short-circuit detection circuits 260_1 to 260_3 detect a short-circuited LED among a plurality of LEDs included in the display panel 110. In one embodiment, the short-circuit detection circuits 260_1 to 260_3 may determine whether each of the LEDs is short-circuited using a channel voltage generated when a channel current is supplied through the channel lines CL1 to CL3 to the LEDs connected to the scan lines SL1 to SL3 selected by the scan driving circuit 122. For example, the short-circuit detection circuits 260_1 to 260_3 may detect an LED whose channel voltage is lower than a predetermined reference voltage as a short-circuited LED.

[0096] When a short-circuited LED is detected, the short-circuit detection circuits 260_1 to 260_3 can generate and store the short-circuited LED's position information based on the information about the scan lines SL1 to SL3 and the channel lines CL1 to CL3 to which the short-circuited LED is connected. For example, when the short-circuited LED is connected to the first scan line SL1 and the first channel line CL1, the short-circuit detection circuits 260_1 to 260_3 can generate and store the short-circuited LED's position information as (1, 1). Hereinafter, for ease of description, the scan line to which the short-circuited LED is connected is referred to as a target scan line, and the channel line to which the short-circuited LED is connected is referred to as a target channel line.

[0097] The short-circuit detection circuits 260_1 to 260_3 can provide the data controller 126 with the position information of the short-circuited LED. Hereinafter, for ease of description, it is assumed that the first LED L11 connected to the first scan line SL1 and the first channel line CL1 is short-circuited. According to this example, the first scan line SL1 becomes the target scan line, and the first channel line CL1 becomes the target channel line.

[0098] When the driving of the target scan line SL1 to which the short-circuited LED L11 is connected is terminated, the data controller 126 may float the target scan line SL1 based on the position information of the short-circuited LED L11 transmitted from the short-circuited detection circuits 260_1 to 260_3. Figure 7 As shown, when the light-emitting period of the short-circuited LED L11 ends and thus the scan switch of the target scan line SL1 to which the short-circuited LED L11 is connected is turned off again, the data controller 126 generates a precharge control signal PCS_1 for turning off the first precharge switch PSW1 connected to the target scan line SL1, and applies the precharge control signal PCS_1 to the first precharge switch PSW1.

[0099] Therefore, if Figure 7 As shown, after the first scan switch SW1 connected to the target scan line SL1 is turned off, the first precharge switch PSW1 connected to the target scan line SL1 is turned off, so that the target scan line SL is in a floating state. Therefore, the target scan line SL1 to which the short-circuited LED L11 is connected remains in a floating state until the target scan line SL1 is driven again. In the floating state, the voltage of the target scan line SL1 can be maintained at a level lower than the scan-off voltage when the first scan switch SW1 connected to the target scan line SL1 is turned off and higher than the ground level when the scan switch is turned on.

[0100] At the same time, when the short-circuited LED L11 emits light, the data controller 126 may block the supply of the channel current of the target channel line CL1 connected to the short-circuited LED L11 based on the position information of the short-circuited LED L11 sent from the short-circuited detection circuits 260_1 to 260_3. Figure 7 As shown, when the short-circuited LED L11 emits light, the data controller 126 may generate a first PWM control signal PWM_1 for turning off the first PWM switch 230_1 of the target channel line CL1 to which the short-circuited LED L11 is connected. Therefore, the supply of channel current to the short-circuited LED L11 is blocked.

[0101] In one embodiment, when the short-circuited LED L11 emits light, the data controller 126 may also block the supply of the reference voltage VOFF to the target channel line CL1 connected to the short-circuited LED L11. Figure 7 As shown, when the short-circuited LED L11 emits light, the first channel voltage V_CH1 of the target channel line CL1 to which the short-circuited LED L11 is connected can be maintained at the level of the ground GND. To this end, when the short-circuited LED L11 emits light, the data controller 126 can generate a first reference voltage applying signal RVS_1 for turning off the first reference voltage applying switch 250_1 to the target channel line CL1 to which the short-circuited LED L11 is connected, and transmit the first reference voltage applying signal RVS_1 to the first reference voltage applying switch 250_1.

[0102] As described above, according to the present disclosure, when a short-circuited LED L11 is detected by the short-circuit detection circuits 260_1 to 260_3, the data controller 126 can turn off the first pre-charge switch PSW_1 connected to the target scan line SL1 to which the short-circuited LED L11 is connected, thereby maintaining the target scan line SL1 in a floating state, and can simultaneously turn off the first PWM switch 230_1 of the target channel line CL1 to which the short-circuited LED L11 is connected, thereby blocking the supply of channel current through the target channel line CL1, thereby preventing the occurrence of a phenomenon in which all LEDs connected to the target channel line CL1 become brighter or darker due to the short-circuited LED L11.

[0103] Meanwhile, in order to maximize the effect of preventing image quality defects, the LED display driving circuit 120 according to one embodiment of the present disclosure may further include a brightness compensation circuit 130 .

[0104] Specifically, when the short circuit LED L11 occurs, the data controller 126 makes the target scan line SL1 float, as shown in FIG. Figure 7As shown in FIG. 1 , when driving the other normal LEDs L12 to L13 connected to the target channel line CL1, the time it takes for the first channel voltage V_CH1 to increase from the reference voltage to the maximum value may be longer than when no short-circuited LEDs occur. That is, when any one of the scan lines SL2 and SL3 other than the target scan line SL1 is selected, when the increasing inclination of the first channel voltage V_CH1 of the target channel line CL1 is less than the reference inclination when no short-circuited LEDs occur, the brightness compensation circuit 130 may determine to compensate for the brightness of the normal LEDs connected to the target channel line CL1.

[0105] According to the above example, during the light emission period of the normal LEDs, the brightness of the normal LEDs L12 and L13 connected to the target channel line CL1 may be compensated using the brightness compensation circuit 130 .

[0106] Specifically, the brightness compensation circuit 130 may compensate for the brightness of the normal LEDs L12 and L13 connected to the target channel line CL1 using the first channel voltage V_CH1 of the target channel line CL1 .

[0107] In one embodiment, Figure 8A As shown, the brightness compensation circuit 130 can generate a comparison signal COMP by comparing the first channel voltage V_CH1 of the target channel line CL1 with a predetermined reference voltage VREF, and generate a brightness compensation amount Δt as a time Δt corresponding to the difference between the comparison signal COMP and the first PWM signal PWM_1 to be provided to the first PWM switch 230_1 of the target channel line CL1. The brightness compensation circuit 130 provides the brightness compensation amount Δt to the data controller 126. The data controller 126 generates a final first PWM control signal PWM_1′ by increasing the ON period of the first PWM control signal PWM_1 to be provided to the first PWM switch 230_1 of the target channel line CL1 by an amount equal to the brightness compensation amount Δt, and provides the generated final first PWM control signal PWM_1′ to the first PWM switch 230_1 of the target channel line CL1. Therefore, the first PWM switch 230_1 connected to the target channel line CL1 is additionally turned on by the brightness compensation amount Δt, and thus, the time during which the first channel voltage V_CH1 is maintained at the maximum value when the normal LEDs L12 and L13 emit light increases by as much as the brightness compensation amount Δt, so that the brightness of the normal LEDs L12 and L13 can be increased.

[0108] In the following, reference will be made to Figure 8B The configuration of the brightness compensation circuit 130 for realizing the above-mentioned functions according to one embodiment of the present disclosure is described in more detail.

[0109] Figure 8B : is a block diagram showing the configuration of a brightness compensation circuit according to one embodiment of the present disclosure. Figure 8B As shown, the brightness compensation circuit 130 according to one embodiment of the present disclosure may include a comparator 810 , a logic AND operator 820 , a counter 830 , and a subtractor 840 .

[0110] The comparator 810 compares the reference voltage VREF with the first channel voltage V_CH1 of the target channel line CL1 to generate a comparison signal COMP. For example, when the reference voltage VREF is greater than the first channel voltage V_CH1 of the target channel line CL1, the comparator 810 outputs a high-level comparison signal COMP. When the reference voltage VREF is less than or equal to the first channel voltage V_CH1 of the target channel line CL1, the comparator 810 outputs a low-level comparison signal COMP.

[0111] The logical AND operator 820 performs a logical AND operation on the comparison signal COMP output from the comparator 810 and the internal clock GCLK. Therefore, only a period in which the comparison signal COMP is at a high level can be output in synchronization with the internal clock GCLK.

[0112] The counter 830 counts the number of clocks output from the logical AND operator 820 , that is, counts the number of clocks during which the comparison signal COMP is maintained at a high level.

[0113] The subtractor 840 calculates the brightness compensation amount Δt by calculating the difference between the initial first PWM control signal PWM_1 to be supplied to the first PWM switch of the target channel line CL1 and the count value output from the counter 830. The subtractor 840 supplies the calculated brightness compensation amount Δt to the data controller 126.

[0114] The data controller 126 increases the ON period of the initial first PWM control signal PWM_1 to be supplied to the first PWM switch 230_1 of the target channel line CL1 by the brightness compensation amount Δt to generate the final first PWM control signal PWM_1′ and supplies the final first PWM control signal PWM_1′ to the first PWM switch 230_1 of the target channel line CL1. Figure 7 As shown, the first PWM switch 230_1 connected to the target channel line CL1 is additionally turned on by the brightness compensation amount Δt, and therefore, the time for which the first channel voltage V_CH1 is maintained at the maximum value when the normal LEDs L12 and L13 emit light increases by as much as the brightness compensation amount Δt, so that the brightness of the normal LEDs L12 and L13 can be increased.

[0115] At the same time, if Figure 8BAs shown, when generating the final first PWM control signal PWM_1 ′, the data controller 126 may additionally reflect the offset value stored in the offset register 850 in the final first PWM control signal PWM_1 ′.

[0116] Although it has been described in the above example that the ON period of the initial first PWM control signal PWM_1 increases by as much as the brightness compensation amount Δt, the ON period of the initial first PWM control signal PWM_1 may decrease by as much as the brightness compensation amount Δt.

[0117] Although the above example describes comparing the first channel voltage V_CH1 of the target channel line CL1 with the reference voltage VREF, in another example, the first channel voltage V_CH1 of the target channel line CL1 may be compared with the channel voltage of a normal channel line adjacent to the target channel line CL1. Hereinafter, the description will be made assuming that the second channel line CL2 adjacent to the target channel line CL1 is a normal channel line.

[0118] Specifically, if Figure 9A As shown, the brightness compensation circuit 130 can generate a comparison signal COMP by comparing the first channel voltage V_CH1 of the target channel line CL1 with the second channel voltage V_CH2 of the normal channel line CL2, and generate a brightness compensation amount Δt as a time Δt corresponding to the difference between the comparison signal COMP and the initial first PWM signal PWM_1 to be provided to the first PWM switch 230_1 of the target channel line CL1. The brightness compensation circuit 130 provides the brightness compensation amount Δt to the data controller 126. The data controller 126 generates a final first PWM control signal PWM_1′ by increasing the ON period of the first PWM control signal PWM_1 to be provided to the first PWM switch 230_1 of the target channel line CL1 by an amount equal to the brightness compensation amount Δt, and provides the generated final first PWM control signal PWM_1′ to the first PWM switch 230_1 of the target channel line CL1.

[0119] Therefore, the first PWM switch 230_1 connected to the target channel line CL1 is additionally turned on by the brightness compensation amount Δt, and thus, the time during which the first channel voltage V_CH1 is maintained at the maximum value when the normal LEDs L12 and L13 emit light increases by as much as the brightness compensation amount Δt, so that the brightness of the normal LEDs L12 and L13 can be increased.

[0120] In the following, reference will be made to Figure 9B The configuration of the brightness compensation circuit 130 for realizing the above-mentioned functions according to another embodiment of the present disclosure is described in more detail.

[0121] Figure 9B : is a block diagram showing the configuration of a brightness compensation circuit according to another embodiment of the present disclosure. Figure 9B As shown, the brightness compensation circuit 130 according to another embodiment of the present disclosure may include a comparator 910 , a logic AND operator 920 , a counter 930 , and a subtractor 940 .

[0122] The comparator 910 compares the first channel voltage V_CH1 of the target channel line CL1 with the second channel voltage V_CH2 of the normal channel line CL2 to generate a comparison signal COMP. For example, when the second channel voltage V_CH2 of the normal channel line CL2 is greater than the first channel voltage V_CH1 of the target channel line CL1, the comparator 910 outputs a high-level comparison signal COMP. When the second channel voltage V_CH2 of the normal channel line CL2 is less than or equal to the first channel voltage V_CH1 of the target channel line CL1, the comparator 910 outputs a low-level comparison signal COMP.

[0123] The logical AND operator 920 performs a logical AND operation on the comparison signal COMP output from the comparator 910 and the internal clock GCLK. Therefore, only a period in which the comparison signal COMP is at a high level can be output in synchronization with the internal clock GCLK.

[0124] The counter 930 counts the number of clocks output from the logical AND operator 920 , that is, counts the number of clocks during which the comparison signal COMP is maintained at a high level.

[0125] The subtractor 940 calculates the brightness compensation amount Δt by calculating the difference between the initial first PWM control signal PWM_1 to be supplied to the first PWM switch 230_1 of the target channel line CL1 and the count value output from the counter 930. The subtractor 940 supplies the calculated brightness compensation amount Δt to the data controller 126.

[0126] The data controller 126 increases the ON period of the initial first PWM control signal PWM_1 to be supplied to the first PWM switch 230_1 of the target channel line CL1 by an amount equal to the brightness compensation amount Δt to generate a final first PWM control signal PWM_1′, and supplies the final first PWM control signal PWM_1′ to the first PWM switch 230_1 of the target channel line CL1. Therefore, the first PWM switch 230_1 connected to the target channel line CL1 is additionally turned on by an amount equal to the brightness compensation amount Δt. Therefore, the time during which the first channel voltage V_CH1 is maintained at its maximum value when the normal LEDs L12 and L13 emit light increases by an amount equal to the brightness compensation amount Δt, thereby increasing the brightness of the normal LEDs L12 and L13.

[0127] At the same time, if Figure 9B As shown, when generating the final first PWM control signal PWM_1 ′, the data controller 126 may additionally reflect the offset value stored in the offset register 950 in the final first PWM control signal PWM_1 ′.

[0128] Although it has been described in the above example that the ON period of the initial first PWM control signal PWM_1 increases by as much as the brightness compensation amount Δt, the ON period of the initial first PWM control signal PWM_1 may decrease by as much as the brightness compensation amount Δt.

[0129] As described above, according to the present disclosure, Figure 10A and Figure 10B As shown, only a point defect (dark point) occurs which causes only the short-circuited LED to not emit light, and a line defect (dark line) which causes a change in the brightness of all other normal LEDs connected to the target channel line to which the short-circuited LED is connected is prevented, thereby having the effect of being able to present image quality close to normal without repairing or replacing the short-circuited LED.

[0130] According to the present disclosure, by floating the target scan line connected to the short-circuited light emitting diode (LED) during the non-light-emitting period of the short-circuited LED, only a point defect (dark point) that causes only the short-circuited LED to not emit light occurs, and a line defect (dark line) that causes the brightness of all other normal LEDs connected to the target channel line to which the short-circuited LED is connected to change is prevented, thereby having the effect of being able to present image quality close to normal without repairing or replacing the short-circuited LED.

[0131] In addition, according to the present disclosure, when a normal LED connected to a target channel line emits light, the brightness of the normal LED can be compensated by compensating a pulse width modulation (PWM) control signal for the normal LED to emit light, thereby having the effect of preventing image quality defects due to a short circuit of the LED.

[0132] It will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is intended to cover modifications and variations of the present disclosure.

[0133] The various embodiments described above can be combined to provide further embodiments. These and other changes can be made to the embodiments in light of the above detailed description. Generally, in the appended claims, the terms used should not be interpreted as limiting the claims to the specific embodiments disclosed in the specification and claims, but should be interpreted to include all possible embodiments and the full range of equivalents to which these claims are entitled. Therefore, the claims are not limited by this disclosure.

[0134] CROSS-REFERENCE TO RELATED APPLICATIONS

[0135] This application claims the benefit of Korean Patent Application No. 10-2024-0037414, filed on March 18, 2024, and Korean Patent Application No. 10-2025-0018333, filed on February 12, 2025, which are hereby incorporated by reference as if fully set forth herein.

Claims

1. A light emitting diode (LED) display driving circuit, comprising: a channel driving circuit configured to provide a channel current to each of the plurality of channel lines according to a pulse width modulation (PWM) control signal and to cause a plurality of LEDs connected to each channel line to emit light; a scan driving circuit comprising a plurality of scan switches and a plurality of precharge switches, the plurality of scan switches being connected to a plurality of scan lines and selectively turned on or off according to scan signals to select a scan line connected to an LED to be emitted, the plurality of precharge switches being connected to the plurality of scan lines and configured to operate complementarily with the scan switches according to a precharge control signal, and being turned on when each of the scan switches is off to supply a precharge voltage to the corresponding scan line; as well as a data controller configured to generate the PWM control signal, the scan signal, and the pre-charge control signal, and, upon detecting a short-circuited LED among the plurality of LEDs, maintain the target scan line in a floating state by turning off a pre-charge switch connected to the target scan line when a scan switch of the target scan line to which the short-circuited LED is connected is turned off.

2. The LED display driving circuit according to claim 1, wherein: The channel driving circuit includes: a plurality of channel current sources provided for each of the channel lines and configured to generate a channel current to be provided through each channel line using an externally provided voltage; a plurality of PWM switches connected between the channel wires and the channel current sources and turned on or off according to the PWM control signal to control the amount of the channel current provided to each channel wire; and a short-circuit detection circuit configured to detect the short-circuited LED among the plurality of LEDs, The data controller generates the PWM control signal for turning off the PWM switch of the target channel line connected to the short-circuited LED during the on-period of the scan switch of the target scan line.

3. The LED display driving circuit according to claim 1, wherein: The channel driving circuit includes a short circuit detection circuit configured to detect the short-circuited LED among the plurality of LEDs; and When a specific scan line is selected by the scan driving circuit, the short detection circuit determines whether each LED is short-circuited based on a channel voltage of each channel line according to the channel current supplied through each channel line.

4. The LED display driving circuit according to claim 3, wherein: The short-circuit detection circuit detects an LED connected to a channel line having a channel voltage less than a predetermined reference voltage as the short-circuited LED.

5. The LED display driving circuit according to claim 1 , further comprising a brightness compensation circuit, wherein when any one of the scan lines other than the target scan line is selected and when an increase slope of the channel voltage due to the channel current supplied to the target channel line is less than a reference slope, the brightness of the normal LED connected to the target channel line connected to the short-circuited LED is compensated.

6. The LED display driving circuit according to claim 5, wherein: The brightness compensation circuit generates a comparison signal by comparing the channel voltage of the target channel line with a predetermined reference voltage, and calculates a difference between the comparison signal and an initial PWM control signal for the target channel line as a brightness compensation amount; and The data controller generates the PWM control signal for controlling the PWM switch connected to the target channel line by adjusting an ON period of the initial PWM control signal by as much as the brightness compensation amount.

7. The LED display driving circuit according to claim 6, wherein: The brightness compensation circuit comprises: a comparator configured to compare the predetermined reference voltage with the channel voltage of the target channel line to generate the comparison signal; a logical AND operator configured to perform a logical AND operation on the comparison signal output from the comparator and an internal clock; a counter configured to count the number of clocks during which the AND operation result output from the logical AND operator remains at a high level; and A subtractor is configured to calculate a difference between the initial PWM control signal PWM and a count value output from the counter as the brightness compensation amount.

8. The LED display driving circuit according to claim 5, wherein: The brightness compensation circuit generates a comparison signal by comparing the channel voltage of the target channel line with the channel voltage of a normal channel line adjacent to the target channel line, and calculates a difference between the comparison signal and an initial PWM control signal for the target channel line as a brightness compensation amount; and The data controller generates the PWM control signal for controlling the PWM switch connected to the target channel line by adjusting an ON period of the initial PWM control signal by as much as the brightness compensation amount.

9. The LED display driving circuit according to claim 8, wherein: The brightness compensation circuit comprises: a comparator configured to compare the channel voltage of the normal channel line with the channel voltage of the target channel line to generate the comparison signal; a logical AND operator configured to perform a logical AND operation on the comparison signal output from the comparator and an internal clock; a counter configured to count the number of clocks during which the AND operation result output from the logical AND operator remains at a high level; and A subtractor is configured to calculate a difference between the initial PWM control signal and a count value output from the counter as the brightness compensation amount.

10. The LED display driving circuit according to claim 1, wherein: When a specific scan line is selected by the scan driving circuit, a channel voltage of each channel line according to the channel current provided through each channel line increases from a reference voltage level higher than a ground level according to the supply of the channel current, and decreases to the reference voltage level when the supply of the channel current stops.

11. A light emitting diode (LED) display device, comprising: a display panel comprising a plurality of LEDs disposed in a plurality of sub-pixels, where a plurality of channel lines and a plurality of scan lines intersect; as well as an LED display driving circuit configured to provide channel current to the plurality of LEDs and cause the plurality of LEDs to emit light, Wherein, the LED display driving circuit includes: a channel driving circuit, wherein the channel driving circuit is configured to provide the channel current through each channel line according to a pulse width modulation (PWM) control signal; a scan driving circuit comprising a plurality of scan switches and a plurality of precharge switches, the plurality of scan switches being connected to a plurality of scan lines and selectively turned on or off according to scan signals to select a scan line connected to an LED to be emitted, the plurality of precharge switches being connected to the plurality of scan lines and configured to operate complementarily with the scan switches according to a precharge control signal and being turned on to supply a precharge voltage to the corresponding scan line when each of the scan switches is turned off; and a data controller configured to generate the PWM control signal, the scan signal, and the pre-charge control signal, and, upon detecting a short-circuited LED among the plurality of LEDs, maintain the target scan line in a floating state by turning off a pre-charge switch connected to the target scan line when a scan switch of the target scan line to which the short-circuited LED is connected is turned off.

12. The LED display device according to claim 11, wherein: The LED display driving circuit includes a brightness compensation circuit configured to compensate for the brightness of a normal LED connected to the target channel line to which the short-circuited LED is connected when any one of the scan lines other than the target scan line is selected and when an increase slope of the channel voltage due to the channel current supplied to the target channel line is less than a reference slope.

13. The LED display device according to claim 12, wherein: The brightness compensation circuit generates a comparison signal by comparing a predetermined reference voltage or a channel voltage of a normal channel line adjacent to the target channel line with the channel voltage of the target channel line, and calculates a difference between the comparison signal and an initial PWM control signal for the target channel line as a brightness compensation amount; and The data controller generates the PWM control signal for controlling the PWM switch connected to the target channel line by adjusting an ON period of the initial PWM control signal by as much as the brightness compensation amount.

14. The LED display device according to claim 11, wherein: The channel driving circuit includes: a plurality of channel current sources provided for each of the channel lines and configured to generate a channel current to be provided through each channel line using an externally provided voltage; a plurality of PWM switches connected between the channel wires and the channel current sources and turned on or off according to the PWM control signal to control the amount of the channel current provided to each channel wire; and a short circuit detection circuit configured to detect a short-circuited LED among the plurality of LEDs, The data controller generates the PWM control signal for turning off the PWM switch of the target channel line connected to the short-circuited LED during the on-period of the scan switch of the target scan line.

15. The LED display device according to claim 11, wherein: The channel driving circuit includes a short circuit detection circuit configured to detect a short circuit LED among the plurality of LEDs; and When a specific scan line is selected by the scan driving circuit, the short detection circuit determines whether each LED is short-circuited based on a channel voltage of each channel line according to the channel current supplied through each channel line.

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