KR102654549B1 - Data Driving Device For Determining Faulty Bonding And Display Device Including The Same - Google Patents

Abstract

A data driving device for determining bonding defects according to an aspect of the present invention capable of determining bonding defects between a data driving device and a display panel supplies a voltage of a first level to a first data line to a first channel processing unit that charges the first load capacitor; a second channel processing unit that supplies a second level voltage to a second data line to charge a second load capacitor of the second data line; a channel mux connecting the first channel processing unit to the first data line and connecting the second channel processing unit to the second data line; a charge sharing line including a first switch that selectively connects the first data line and the second data line, and sharing charges charged in the first and second load capacitors when the first switch is turned on; a control unit that controls the channel mux and the first switch; and a comparator that compares the output voltage of the charge sharing line with a reference voltage and outputs a comparison voltage that indicates whether the bonding between the data driving device and the display panel is defective.

Description

Data driving device for determining faulty bonding and display device including the same {Data Driving Device For Determining Faulty Bonding And Display Device Including The Same}

The present invention relates to a data driving device.

As the information society develops, the demand for display devices for displaying images is increasing in various forms. Accordingly, recently, various types of display devices such as liquid crystal display devices (LCDs) and organic light emitting display devices (OLEDs) have been used.

A display device includes a display panel including data lines, gate lines, a plurality of pixels connected to the data lines and the gate lines, a gate driver that supplies gate signals to the gate lines, and a source signal to the data lines. It is provided with a data driver that supplies data, and a timing control unit that controls the operation timing of the gate driver and the data driver.

At this time, the data driving device may be mounted on a flexible film using a COF (Chip On Film) method or a COG (Chip On Glass) method and bonded to the pads of the display panel using a TAB (Tape Automated Bonding) method.

Since the data driving device and the display panel are bonded by applying physical force, the bonding may open or be shorted to another line. In this case, the source signal may not be transmitted to the data line or overcurrent may flow, so a process of determining whether bonding is defective is essential.

However, in the past, because bonding defects were determined by simply driving the display device, there was a problem that appropriate measures could not be taken because it was impossible to know whether the bonding was open or shorted.

In addition, incorrect actions may cause problems in other configurations of the display device, as well as increased cost losses as the bonding process is performed again.

The present invention is intended to solve the above-mentioned problems, and its technical task is to provide a data driving device that can determine bonding defects between the data driving device and the display panel and a display device including the same.

The technical task is to provide a data driving device that determines bonding defects and a display device including the same, which can independently determine bonding defects in the data driving device.

In addition, the present invention aims to provide a data driving device for determining bonding defects that can measure bonding resistance formed by bonding between a data driving device and a display panel, and a display device including the same.

A data driving device for determining bonding defects according to an aspect of the present invention for achieving the above-described technical problem supplies a voltage of a first level to a first data line to charge the first load capacitor of the first data line. First channel processing unit; a second channel processing unit that supplies a second level voltage to a second data line to charge a second load capacitor of the second data line; a channel mux connecting the first channel processing unit to the first data line and connecting the second channel processing unit to the second data line; a charge sharing line including a first switch that selectively connects the first data line and the second data line, and sharing charges charged in the first and second load capacitors when the first switch is turned on; a control unit that controls the channel mux and the first switch; and a comparator that compares the output voltage of the charge sharing line with a reference voltage and outputs a comparison voltage that indicates whether the bonding between the data driving device and the display panel is defective.

In addition, a display device for determining a bonding defect according to another aspect of the present invention includes a first load capacitor connected to a first data line and charged with a voltage of a first level; a second load capacitor connected to the second data line and charged with a second level voltage; a charge sharing line connected to the first and second data lines to share the charges charged in the first and second load capacitors when the charging of the first and second load capacitors is completed; and a determination unit to determine whether bonding between the data driving device and the display panel is defective using the output voltage of the charge sharing line.

According to the present invention, since it is possible to determine the bonding defect between the data driving device and the display panel, not only can appropriate measures be taken according to the bonding defect, but also the data voltage supplied from the data driving device to the display panel is supplied. This has the effect of preventing overcurrent from flowing into the display panel.

In addition, according to the present invention, since the data driving device itself can determine bonding defects, a separate configuration for determining bonding defects is not required, which not only simplifies the manufacturing process but also lowers the manufacturing cost. there is.

In addition, according to the present invention, since the data driving device itself can determine bonding defects, not only can bonding defects be determined before the display device is shipped, but also bonding defects can be determined even after the display device is shipped. It has the effect of enabling immediate action in response to bonding defects.

In addition, according to the present invention, since the bonding resistance can be measured, the tester does not need to manually measure the bonding resistance every time, which not only increases the test efficiency, but also improves the accuracy of the test by performing it automatically. .

Figure 1 is a diagram showing a perspective view of a display device to which a data driving device for determining bonding defects is applied according to an embodiment of the present invention.
Figure 2 is a diagram showing a data driving device and a display panel bonded according to an embodiment of the present invention.
FIG. 3 is a diagram showing an example of an output voltage graph of a charge sharing line when the first switch is turned on and the charges of the first and second load capacitors are shared.
Figure 4 is a timing diagram showing a method of determining bonding defects by charging the first and second load capacitors by the first and second channel processing units according to an embodiment of the present invention.
Figure 5 is a timing diagram showing a method of determining bonding defects by charging the first and second load capacitors using the second switch and the ground switch according to an embodiment of the present invention.
Figure 6 is a diagram showing that the charge sharing line according to another embodiment of the present invention further includes an external capacitor line connected to an external capacitor.
Figure 7 is a flow chart showing a method for determining bonding defects using a data driving device according to an embodiment of the present invention.
Figure 8 is a flowchart showing a method of determining whether a data driving device has a bonding defect according to an embodiment of the present invention.

When 'includes', 'has', 'consists of', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. In cases where a component is expressed in the singular, the plural is included unless specifically stated otherwise.

When interpreting a component, it is interpreted to include the margin of error even if there is no separate explicit description.

Although first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are merely used to distinguish one component from another. Accordingly, the first component mentioned below may also be the second component within the technical spirit of the present invention.

The term “at least one” should be understood to include all possible combinations from one or more related items. For example, “at least one of the first, second, and third items” means each of the first, second, or third items, as well as two of the first, second, and third items. It can mean a combination of all items that can be presented from more than one.

Each feature of the various embodiments of the present invention can be combined or combined with each other, partially or entirely, and various technical interconnections and operations are possible, and each embodiment may be implemented independently of each other or together in a related relationship. It may be possible.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 is a diagram showing a perspective view of a display device to which a data driving device for determining bonding defects is applied according to an embodiment of the present invention.

Hereinafter, the display device 100 according to an embodiment of the present invention will be described as an organic light emitting display, but is not limited thereto. That is, the display device 100 according to an embodiment of the present invention is not only an organic light emitting display device, but also a liquid crystal display device, a field emission display device, and a quantum dot display device. It may be implemented as either a Lighting Emitting Diode, or an Electrophoresis Display.

Referring to FIG. 1, the display device 100 according to an embodiment of the present invention includes a display panel 110, a timing control unit 130, a circuit board 140, a flexible film 150, and a device for determining bonding defects. Includes a data driving device 200 (hereinafter referred to as 'data driving device').

The display panel 110 includes a first substrate 111 and a second substrate 112. The first substrate 110 may be a plastic film or a glass substrate. The second substrate 112 may be a plastic film, a glass substrate, or an encapsulation film.

Gate lines, data lines, and pixels are formed on one side of the first substrate 111 opposite the second substrate 112. Pixels are formed in an area defined by the intersection structure of gate lines and data lines.

Each pixel may include a thin film transistor or an organic light emitting device. At this time, the organic light emitting device may include a first electrode, an organic light emitting layer, and a second electrode. Each pixel uses a thin film transistor to supply a predetermined current to the organic light emitting device according to the data voltage of the data line when a gate signal is input from the gate line. Because of this, the organic light emitting element of each pixel can emit light with a predetermined brightness according to a predetermined current.

The display panel 110 can be divided into a display area in which each pixel is formed to display an image and a non-display area in which the image is not displayed. Gate lines, data lines, and pixels may be formed in the display area. Gate pads and data pads may be formed in the non-display area.

A gate driver (not shown) supplies gate signals to the gate lines according to a gate control signal input from the timing controller 130. The gate driving device may be formed on one or both sides of the display panel 110 using a GIP (Gate Driver In Panel) method. Alternatively, the gate driving device may be manufactured as a driving chip, mounted on a flexible film, and attached to the outside of one or both sides of the display panel 110 using a TAB (Tape Automated Bonding) method.

The timing control unit 130 receives digital video data and timing signals from an external system board through a cable of the circuit board 140. At this time, the timing signal includes a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), a data enable signal (Data Enable, DE), etc.

The timing control unit 130 generates a gate control signal for controlling the operation timing of the gate driving device and a data control signal for controlling the data driving devices 200 based on the timing signal. The timing control unit 170 supplies a gate control signal to the gate driving device and a data control signal to the data driving devices 200.

For this purpose, the timing control unit 130 is a receiver that receives digital video data and timing signals from an external system board, and rearranges the digital video data among the signals received from the receiver to match the display panel 110 to produce the rearranged digital video data. A video data processing unit that generates a video data processing unit, a control signal generating unit that generates a gate control signal and a data control signal for controlling the gate driver and the data driver 200 using the timing signal received from the receiver, and a gate control signal. It includes a transmission unit that outputs to the gate driving device and outputs rearranged digital video data and data control signals to the data driving device 200.

At this time, the gate control signal includes a gate clock (CLK), a start signal (VST), and a gate output enable signal (GOE), and the data control signal includes a source start pulse (SSP) and a source shift clock signal (SSC). , and source output enable signal (SOE).

In the flexible film 150, wires connecting the pads of the display panel 110 and the data driving device 200, and wires connecting the pads of the display panel 110 and the wires of the circuit board 140 are formed. You can. The flexible film 150 may be attached to the pads of the display panel 110 using a TAB (Tape Automated Bonding) method. Additionally, the flexible film 150 can be attached to the pads using an antisotropic conducting film, and thus the pads and the wiring of the flexible film 150 can be connected.

The data driving device 200 receives digital video data and data control signals from the timing control unit 170. The data driving device 200 converts digital video data into analog data voltages according to a data control signal and supplies them to the data lines. When the data driving device 200 is manufactured as a driving chip, the data driving device 200 may be mounted on the flexible film 150 using a COF (Chip On Film) or COP (Chip On Plastic) method.

To this end, the data driving device 200 may be configured to include a shift register unit, a latch unit, a digital-to-analog converter, an output buffer, a channel mux, etc.

The shift register unit outputs a sampling signal using the data control signals received from the timing control unit 130. The latch unit latches the digital video data sequentially received from the timing control unit 130 according to the sampling signal and simultaneously outputs the digital video data to the digital-to-analog converter. The digital-to-analog converter converts the digital video data transmitted from the latch unit into a data voltage and outputs it. The output buffer outputs the data voltage generated from the digital-to-analog converter to data lines according to the data control signal.

The channel mux connects each output buffer stage and data lines to supply the data voltage output to each output buffer to the data line.

In this way, the data driving device 200 operates the display panel 110 by applying a data voltage to each data line connected to the display panel 110.

In particular, the data driving device 200 according to the present invention can determine whether bonding between the data driving device 200 and the display panel 110 is defective.

Accordingly, the data driving device 200 may operate in a display mode or a test mode. The display mode refers to a mode in which the data driving device 200 applies a data voltage to each data line connected to the display panel 110 to operate the display panel 110, and the test mode refers to a mode that determines whether or not there is a bonding defect. means.

In one embodiment, the display mode or test mode may be set by the data driving device 200. In another embodiment, the display mode or test mode may be set by the timing control unit 130. In another embodiment, the display mode or test mode may be set by an external device (not shown).

Hereinafter, the data driving device 200 according to the present invention will be described in more detail with reference to FIG. 2.

Figure 2 is a diagram showing a data driving device and a display panel bonded according to an embodiment of the present invention.

The data driving device 200 according to the present invention includes a first channel processing unit 210, a second channel processing unit 220, a channel mux (230), a charge sharing line (CSL), a control unit 240, and a comparator ( 250). In FIG. 2, the data driving device 200 is shown as including a first channel processing unit 210 and a second channel processing unit 220, but this is only one embodiment, and the data driving device 200 includes one It may include a channel processing unit or three or more channel processing units.

The first channel processing unit 210 supplies a first level voltage to the first data line DL1 to load the first load capacitor ( ) is charged. Specifically, when the first channel processing unit 210 is connected to the first data line DL1 by the channel mux 230, it supplies a first level voltage to the first data line DL1. The first channel processing unit 210 connects the first load capacitor ( ) is charged. At this time, the first level voltage may be a voltage corresponding to the maximum gray level among the plurality of gray levels. Accordingly, the first load capacitor ( ) is charged by the voltage of the first level.

In one embodiment, the first channel processing unit 210 includes a shift register unit, a latch unit, a digital-to-analog converter, and an output buffer. Since the functions of each component have been described above, detailed description will be omitted.

The second channel processing unit 220 supplies a second level voltage to the second data line DL2 to load the second load capacitor ( ) is charged. Specifically, when the second channel processing unit 210 is connected to the second data line DL2 by the channel mux 230, it supplies a second level voltage to the second data line DL2. The second channel processing unit 210 applies the second level voltage to the second load capacitor ( ) is charged. At this time, the second level voltage may be a level voltage corresponding to the minimum gray level among the plurality of gray levels. Accordingly, the second load capacitor ( ) is charged by the voltage of the second level.

In one embodiment, the second channel processing unit 220 includes a shift register unit, a latch unit, a digital-to-analog converter, and an output buffer. Since the function of each component has been described above, detailed description will be omitted.

The channel mux 230 connects the first channel processing unit 210 to the first data line DL1 and connects the second channel processing unit 220 to the second data line DL2. Accordingly, the first load capacitor ( ) and a second load capacitor ( ) is charged by the first channel processing unit 230 and the second channel processing unit 240.

In the charge sharing line (CSL), the first and second load capacitors ( , ) are shared with each other. For this purpose, the charge sharing line (CSL) includes a first switch (S1) that selectively connects the first data line (DL1) and the second data line (DL2), and a third level external voltage (Vexit) connected to the first load capacitor. ( ) is selectively supplied to the first load capacitor ( ) includes a second switch (S2) for charging and a ground switch (S3) for selectively connecting to the ground terminal. At this time, the third level may be a voltage of a corresponding level corresponding to half of the maximum gray level.

The control unit 240 causes the data driving device 200 to operate in a display mode or a test mode. Here, the display mode refers to a mode in which the display panel 110 is operated by applying a data voltage to each data line connected to the display panel 110, and the test mode refers to a mode in which the data driver 200 and the display panel 100 are operated. This refers to a mode that determines bonding defects between livers. Here, bonding defect means open defect, which means that the bonding between the data driving device 200 and the display panel 100 is open, and bonding between the data driving device 200 and the display panel 100 is short-circuited with another line ( This includes short-circuiting defects, which means shorting.

In one embodiment, the control unit 240 can set either a display mode or a test mode. In another embodiment, either the display mode or the test mode may be set by the timing control unit 130, and in another embodiment, either the display mode or the test mode may be set by an external device ( (not shown) may be set.

The control unit 240 includes a first switch (S1), a second switch (S2), and The ground switch (S3) is controlled.

The control unit 240 operates the first load capacitor ( ) and a second load capacitor ( ) The channel mux 230 is turned off and the first switch S1 and the ground switch S3 are turned on so that all charges charged in the channel are discharged. Accordingly, the second load capacitor ( ) is discharged. The control unit 240 turns off the first switch S1 and the ground switch S3 when a predetermined time elapses.

The control unit 240 operates the first load capacitor ( ) and a second load capacitor ( ) is initialized, the first load capacitor ( ) and a second load capacitor ( ) turns on the channel mux 230 so that the charge can be charged. Accordingly, a voltage of the first level is applied to the first data line DL1 by the first channel processing unit 210, and the first load capacitor ( ) is charged. A second level voltage is applied to the second data line DL2 by the second channel processing unit 220 to cause the second load capacitor ( ) is charged. At this time, the first level voltage corresponds to the maximum gray scale voltage, and the second level voltage corresponds to the minimum gray scale voltage. The second level voltage may correspond to the ground level voltage.

When the charging of the first and second load capacitors is completed, the control unit 240 turns off the channel mux 230 and turns on the first switch (S1) to load the first and second loads through the charge sharing line (CSL). Capacitor ( , ) so that the charges charged in it are shared with each other. Accordingly, the first load capacitor ( The voltage of the second load capacitor ( ) and the charge are shared and the voltage (V1) falls to a certain level. Second load capacitor ( ) is the voltage of the first load capacitor ( ), the charge is shared and rises to a certain level of voltage (V1). At this time, the output voltage of the charge sharing line (CSL) is compared with the reference voltage (Vref) by the comparator 250 and output as a comparison voltage (Vout).

When a predetermined time elapses, the control unit 240 turns off the first switch (S1). At this time, the predetermined time may mean the time at which open defects and short circuit defects are determined based on the comparison voltage output by the comparator 250.

In one embodiment, the comparator 250 is connected to the first load capacitor (CSL) in the charge sharing line (CSL). ) and a second load capacitor ( When the first switch (S1) is turned on so that the charge charged in ) is shared, the first output voltage ( ) is compared with the first reference voltage (Vref) to output the first comparison voltage (Vout) at the first point in time. At this time, the first time point refers to the time point when the output voltage of the charge sharing line (CSL) is output as a transient response.

In one embodiment, the comparator 250 generates a first output voltage ( ) is less than or equal to the first reference voltage, the first comparison voltage of high level indicating open bonding is output, and the first output voltage at the first time point ( ) exceeds the first reference voltage, a low-level first comparison voltage indicating normal bonding is output. At this time, the first reference voltage may be set as the first output voltage when the value of the bonding resistor has a value that can be determined to be open.

In one embodiment, the comparator 250 is connected to the first load capacitor (CSL) in the charge sharing line (CSL). ) and a second load capacitor ( When the first switch (S1) is turned on so that the charge charged in ) is shared, the second output voltage at the second time point ( ) is compared with the second reference voltage (Vref) to output a second comparison voltage (Vout). At this time, the second time point refers to the time point when the output voltage of the charge sharing line (CSL) is output as a steady state response.

In one embodiment, the comparator 250 generates a second output voltage ( ) is different from the second reference voltage, outputs a high-level second comparison voltage indicating short bonding, and outputs the second output voltage at the second time point ( ) is equal to the second reference voltage, a low-level second comparison voltage indicating normal bonding is output. At this time, the second reference voltage is the output voltage of the charge sharing line (CSL) in the steady-state response when the short is normal ( ) can be set to the convergence level.

Figure 3 shows the output voltage of the charge sharing line when the first switch (S1) is turned on and the charges of the first and second load capacitors are shared ( ) This is a diagram showing an example of a graph.

As shown in FIG. 3, the first graph (a1) shows the output voltage (a1), which is the standard for normal bonding. ) It is a graph.

The second graph (a2) is open normal because the first output voltage exceeds the first reference voltage (Vref1), and is short normal because the second output voltage converges to the second reference voltage (Vref2).

In the third graph (a3), the short is normal because the second output voltage converges to the second reference voltage (Vref2), but the open is defective because the first output voltage is below the first reference voltage (Vref1).

The fourth graph (a4) is open normally because the first output voltage exceeds the first reference voltage (Vref1), but is short-circuited because the second output voltage is different from the second reference voltage (Vref1).

The display device 100 according to the present invention may further include a determination unit 260 as shown in FIG. 2 . The determination unit 260 determines open failure or short circuit failure according to the comparison voltage output from the comparator 250. Here, the determination unit 260 is shown as a separate configuration from the data driving device 200, but can be implemented as the data driving device 200, and is shown as a separate configuration from the timing control unit 130, but the timing control unit 130 ), and although it is shown as a component included in the display device 100, it may also be implemented as a separate external device.

In one embodiment, the determination unit 260 may determine that the first comparison voltage (Vout) at the first time point output by the comparator 250 is open at a low level, and may determine that the first comparison voltage (Vout) is open at a high level. It can be judged as an open failure.

In one embodiment, the determination unit 260 may determine that the short is normal if the second comparison voltage (Vout) at the second time point output by the comparator 250 is output at a low level, and if it is output at a high level, the determination unit 260 may determine that the short is normal. It can be judged to be a short circuit.

The bonding resistance value between the data driving device and the display panel is determined at the first time point as a transient response on the table where the bonding resistance value is mapped for each output voltage when the bonding between the data driving device and the display panel is determined to be normal. 1 A data driving device that determines bonding defects, characterized in that it is determined by the resistance value mapped to the output voltage.

In one embodiment, when the determination unit 260 determines that the bonding is normal, the bonding resistance value between the data driving device and the display panel is calculated from the first time point, which is a transient response, on a table in which the bonding resistance value is mapped for each output voltage. 1 It can be determined by the resistance value mapped to the output voltage.

At this time, the bonding resistance value table for each output voltage may be a table in which bonding resistance values according to the slope of the first output voltage are mapped. Alternatively, the bonding resistance value table for each output voltage may be a table in which bonding resistance values according to the level of the first output voltage are mapped.

If it is determined that there is a short circuit or open failure, the determination unit 260 can turn off the channel mux 130 to block the data voltage supplied to the data lines when the data driving device 200 operates in the display mode. .

In the above-described embodiment, the first channel processing unit 210 and the second channel processing unit 220 charge the first and second load capacitors to determine bonding defects. In a different modified embodiment, bonding failure can be determined by charging the first and second load capacitors using an external voltage (Vexit).

Hereinafter, detailed description of the same content as the above-described embodiment will be omitted and only content changed when following the modified embodiment will be described.

The control unit 240 operates the first load capacitor ( ) and a second load capacitor ( ) The channel mux 230 is turned off and the first switch S1 and the ground switch S3 are turned on so that all charges charged in the channel are discharged. Accordingly, the second load capacitor ( ) is discharged. The control unit 240 turns off the first switch S1 and the ground switch S3 when a predetermined time elapses.

The control unit 240 operates the first load capacitor ( ) and a second load capacitor ( ) is initialized, the third switch that supplies the third level of external voltage to the first data line is turned on to turn on the first load capacitor ( ) is charged, and the second data line is connected to the ground terminal to create a second load capacitor ( ) Turn on the grounding switch (S3) that discharges.

Accordingly, a third level voltage is applied to the first data line DL1 by the external voltage Vexit, and the first load capacitor ( ) is charged. The second data line DL2 is connected to the second load capacitor ( ) is discharged. At this time, the third level voltage may correspond to a voltage corresponding to half of the maximum gray level.

When charging of the first and second load capacitors is completed, the control unit 240 turns off the second switch (S2) and the ground switch (S3) and turns on the first switch (S1) to open the charge sharing line (CSL). Through the first and second load capacitors ( , ) so that the charges charged in it are shared with each other. Accordingly, the first load capacitor ( The voltage of the second load capacitor ( ) and the charge are shared and the voltage (V2) falls to a certain level. Second load capacitor ( ) is the voltage of the first load capacitor ( ), the charge is shared and rises to a certain level of voltage (V2). At this time, the output voltage of the charge sharing line (CSL) is compared with the reference voltage (Vref) by the comparator 250 and output as a comparison voltage (Vout).

When a predetermined time elapses, the control unit 240 turns off the first switch (S1). At this time, the predetermined time may mean the time at which open defects and short circuit defects are determined based on the comparison voltage output by the comparator 250.

In one embodiment, the comparator 250 is connected to the first load capacitor (CSL) in the charge sharing line (CSL). ) and a second load capacitor ( When the first switch (S1) is turned on so that the charge charged in ) is shared, the first output voltage ( ) is compared with the first reference voltage (Vref) to output the first comparison voltage (Vout). At this time, the first time point refers to the time point when the output voltage of the charge sharing line (CSL) is output as a transient response.

In one embodiment, the comparator 250 generates a first output voltage ( ) is less than or equal to the first reference voltage, the first comparison voltage of high level indicating open bonding is output, and the first output voltage at the first time point ( ) exceeds the first reference voltage, the first comparison voltage is output at a low level indicating normal bonding. At this time, the first reference voltage may be set as the first output voltage when the value of the bonding resistor has a value that can be determined to be open.

In one embodiment, the comparator 250 is connected to the first load capacitor (CSL) in the charge sharing line (CSL). ) and a second load capacitor ( When the first switch (S1) is turned on so that the charge charged in ) is shared, the second output voltage at the second time point ( ) is compared with the second reference voltage (Vref) to output a second comparison voltage (Vout). At this time, the second time point refers to the time point when the output voltage of the charge sharing line (CSL) is output as a steady state response.

In one embodiment, the comparator 250 generates a second output voltage ( ) is different from the second reference voltage, a high-level second comparison voltage indicating short bonding is output, and the second output voltage ( ) is equal to the first reference voltage, the second comparison voltage is output at a low level indicating normal bonding. At this time, the second reference voltage is the output voltage of the charge sharing line (CSL) in the steady-state response when the short is normal ( ) can be set to the convergence level.

In one embodiment, the determination unit 260 may determine that the open is normal if the first comparison voltage (Vout) output by the comparator is output at a low level, and may determine that the open is defective if it is output at a high level. .

In one embodiment, the determination unit 260 may determine that the short is normal if the second comparison voltage (Vout) output by the comparator is output at a low level, and may determine that it is a short circuit defective if it is output at a high level. .

In one embodiment, when the determination unit 260 determines that the bonding is normal, the bonding resistance value between the data driving device and the display panel is calculated from the first time point, which is a transient response, on a table in which the bonding resistance value is mapped for each output voltage. 1 It can be determined by the resistance value mapped to the output voltage.

At this time, the bonding resistance value table for each output voltage may be a table in which bonding resistance values according to the slope of the first output voltage are mapped. Alternatively, the bonding resistance value table for each output voltage may be a table in which bonding resistance values according to the level of the first output voltage are mapped.

If it is determined that there is a short circuit or open failure, the determination unit 260 can turn off the channel mux 130 to block the data voltage supplied to the data lines when the data driving device 200 operates in the display mode. .

Hereinafter, a method for determining bonding defects using a data driving device will be described in detail with reference to FIGS. 4 and 5.

Figure 4 is a timing diagram showing a method of determining bonding defects by charging the first and second load capacitors by the first and second channel processing units according to an embodiment of the present invention.

The control unit 240 sets the operation mode. At this time, the operation mode includes display mode and test mode.

The control unit 240 operates the first load capacitor ( ) and a second load capacitor ( ) The channel mux 230 is turned off and the first switch S1 and the ground switch S3 are turned on so that all charges charged in the channel are discharged. Accordingly, the first load capacitor ( ) and a second load capacitor ( ) is discharged. The voltage of the second load capacitor ( ) can appear as a Low level. When the reset period ends, the control unit 240 turns off the first switch (S1) and the ground switch (S3).

The control unit 240 operates the first load capacitor ( ) and a second load capacitor ( ) turns on the channel mux 230 so that the charge can be charged. Accordingly, a voltage of the first level is applied to the first data line DL1 by the first channel processing unit 210, and the first load capacitor ( ) is charged. A second level voltage is applied to the second data line DL2 by the second channel processing unit 210 to cause the second load capacitor ( ) is charged.

The voltage of the first load capacitor ( ) can appear as a High level because the voltage of the first level is the voltage of the level corresponding to the maximum gray scale, and the voltage of the second load capacitor ( ) may appear as a Low level because the second level voltage is a level voltage corresponding to the minimum gray level.

When the open judgment period (P1) is reached, the control unit 240 connects the first load capacitor ( ) and a second load capacitor ( ) The channel mux 230 is turned off so that the charges charged in the channel are shared, and the first switch S1 is turned on.

Accordingly, the first load capacitor ( ) of voltage ( ) is the second load capacitor ( ) and the charge are shared and the voltage (V1) falls to a certain level. Second load capacitor ( ) of voltage ( ) is the first load capacitor ( ), the charge is shared and rises to a certain level of voltage (V1).

In addition, the output voltage of the charge sharing line (CSL) ( ) is the first load capacitor ( ) and bonding resistance ( ) by the first load capacitor ( ) of voltage ( ) rises to a higher level of voltage (Va). At this time, the comparator 250 output voltage at the first time point ( ) is compared with the first reference voltage (Vref) to output the first comparison voltage (Vout). At this time, the first time point is the output voltage of the charge sharing line (CSL) ( ) refers to the point at which the transient response is output.

When the open judgment period (P1) is reached, the comparator 250 outputs the output voltage ( ) exceeds the first reference level, outputs the first comparison voltage at a low level indicating open normal, and output voltage at the first time point ( ) is less than or equal to the first reference voltage, a high level first comparison voltage indicating an open failure is output.

The determination unit 260 determines that the open is normal when the first comparison voltage output by the comparator 250 is output at a low level, and the determination unit 260 determines that the second comparison voltage output by the comparator 250 is high. If the level is output, it is judged as an open failure.

When the short judgment period (P2) comes, the comparator 250 outputs the output voltage ( ) is the same as the second reference level, outputs a low-level second comparison voltage indicating open normal, and output voltage at the second time point ( ) is different from the second reference voltage, a high-level second comparison voltage indicating a short circuit is output.

The determination unit 260 determines that a short is normal when the second comparison voltage output by the comparator 250 is output at a low level, and the determination unit 260 determines that the second comparison voltage output by the comparator 250 is high. If it outputs at a level, it is judged to be a short circuit fault.

When the determination unit 260 determines that the bonding is normal, the bonding resistance value between the data driving device and the display panel is mapped to the output voltage at the first time, which is a transient response, on a table in which the bonding resistance value is mapped for each output voltage. It can be determined by value. At this time, the bonding resistance value table for each output voltage may be a table in which bonding resistance values according to the slope of the output voltage at the first point of time are mapped. Alternatively, the bonding resistance value table for each output voltage may be a table in which bonding resistance values according to the level of the output voltage at the first point of time are mapped.

If it is determined that there is a short circuit or open failure, the determination unit 260 can turn off the channel mux 130 to block the data voltage supplied to the data lines when the data driving device 200 operates in the display mode. .

When the short determination period P2 ends, the control unit 240 turns off the first switch S1.

Figure 5 is a timing diagram showing a method of determining bonding defects by charging the first and second load capacitors using the second switch and the ground switch according to an embodiment of the present invention.

The control unit 240 sets the operation mode. At this time, the operation mode includes display mode and test mode.

The control unit 240 operates the first load capacitor ( ) and a second load capacitor ( ) The channel mux 230 is turned off and the first switch S1 and the ground switch S3 are turned on so that all charges charged in the channel are discharged. Accordingly, the first load capacitor ( ) and a second load capacitor ( ) is discharged. The voltage of the second load capacitor ( ) can appear as a Low level. When the reset period ends, the control unit 240 turns off the first switch (S1) and the ground switch (S3).

The control unit 240 operates the first load capacitor ( ) and a second load capacitor ( ) Turn on the second switch (S2) and the ground switch (S3) so that the charge can be charged.

When the open judgment period (P1) is reached, the control unit 240 connects the first load capacitor ( ) and a second load capacitor ( ) The second switch (S2) and the ground switch (S3) are turned off so that the charges charged in the battery are shared, and the first switch (S1) is turned on.

Accordingly, the first load capacitor ( ) of voltage ( ) is the second load capacitor ( ) and the charge are shared and the voltage (V2) falls to a certain level. Second load capacitor ( ) of voltage ( ) is the first load capacitor ( ), the charge is shared and rises to a certain level of voltage (V2).

In addition, the output voltage of the charge sharing line (CSL) ( ) is the first load capacitor ( ) and bonding resistance ( ) by the first load capacitor ( ) of voltage ( ) rises to a higher level of voltage (Vb). At this time, the comparator 250 output voltage at the first time point ( ) is compared with the first reference voltage (Vref) to output the first comparison voltage (Vout). At this time, the first time point is the output voltage of the charge sharing line (CSL) ( ) refers to the point at which the transient response is output.

When the open judgment period (P1) is reached, the comparator 250 outputs the output voltage ( ) exceeds the first reference level, outputs the first comparison voltage at a low level indicating open normal, and output voltage at the first time point ( ) is less than or equal to the first reference voltage, a high level first comparison voltage indicating an open failure is output.

The determination unit 260 determines that the open is normal when the first comparison voltage output by the comparator 250 is output at a low level, and the determination unit 260 determines that the first comparison voltage output by the comparator 250 is high. If the level is output, it is judged as an open failure.

When the short judgment period (P2) comes, the comparator 250 outputs the output voltage ( ) is the same as the second reference level, outputs a low-level second comparison voltage indicating open normal, and output voltage at the second time point ( ) is different from the second reference voltage, a high-level second comparison voltage indicating a short circuit is output.

The determination unit 260 determines that a short is normal when the second comparison voltage output by the comparator 250 is output at a low level, and the determination unit 260 determines that the second comparison voltage output by the comparator 250 is high. If it outputs at a level, it is judged to be a short circuit fault.

If it is determined that the bonding is normal, the determination unit 260 determines the bonding resistance value between the data driving device 200 and the display panel 110 using the output voltage at the first time point to determine the bonding resistance value between the data driving device 200 and the display panel ( 110), the bonding resistance value can be determined by bonding.

If it is determined that there is a short circuit or open failure, the determination unit 260 can turn off the channel mux 130 to block the data voltage supplied to the data lines when the data driving device 200 operates in the display mode. .

When the short determination period P2 ends, the control unit 240 turns off the first switch S1.

Unlike the above-described embodiment, the charge sharing line (CSL) may further include an external capacitor line connected to an external capacitor. Hereinafter, with reference to FIG. 6, it will be described in detail that the charge sharing line (CSL) is connected to an external capacitor through an external capacitor line.

Figure 6 is a diagram showing that the charge sharing line according to another embodiment of the present invention further includes an external capacitor line connected to an external capacitor.

As shown in FIG. 6, the charge sharing line (CSL) further includes an external capacitor line (CL).

The external capacitor line (CL) is connected to the external capacitor (Cexit). The external capacitor (Cexit) is installed on one side of the display panel 110, and the first load capacitor ( ) and the second load capacitor ( ) has a value greater than the capacitance of

Accordingly, the external capacitor (Cexit) is connected to the first load capacitor ( ) and a second load capacitor ( ) and charge sharing lines (CSL).

Typically the first load capacitor ( ) and a second load capacitor ( ) has a low capacitance, so the output voltage of the charge sharing line (CSL) due to charge sharing ( )'s rise rate is very high. Therefore, the external capacitor line (CL) according to the present invention is connected to the external capacitor (Cexit), and the output voltage increase rate of the charge sharing line (CSL) is reduced by the external capacitor (Cexit).

In this way, the present invention provides an output voltage of the charge sharing line (CSL) ( ) has the effect of strengthening the stability of the data driving device operating in test mode as the output voltage rise rate is reduced.

Hereinafter, a method for determining bonding defects using a data driving device will be described in detail with reference to FIGS. 7 and 8.

Figure 7 is a flow chart showing a method for determining bonding defects using a data driving device according to an embodiment of the present invention.

The data driving device grounds the charge sharing line to initialize the charges charged in the first load capacitor and the second load capacitor (S700)

When the first load capacitor and the second load capacitor are initialized, the data driving device charges the first load capacitor of the first data line to the voltage of the first level and charges the second load capacitor of the second data line to the voltage of the second level. Charge it (S710).

At this time, the first level voltage may be a voltage corresponding to the maximum gray scale, and the second level voltage may be a voltage corresponding to the minimum gray scale and may be a ground level voltage. Alternatively, the first load capacitor may be charged with a third level voltage rather than the first and second level voltages, and the second load capacitor may be charged with a ground level voltage. That is, the first load capacitor and the second load capacitor may be charged at different level voltages.

When the first and second load capacitors are completely charged, the data driving device shares the charges charged in the first and second load capacitors through a charge sharing line connecting the first and second data lines (S720). .

When charge is shared between the first and second load capacitors, the data driving device uses the output voltage of the charge sharing line to determine whether the bonding between the data driving device and the display panel is defective (S730).

Hereinafter, with reference to FIG. 8, how the data driving device determines whether bonding is defective will be described in more detail.

Figure 8 is a flow chart showing how the data driving device according to an embodiment of the present invention determines whether there is a bonding defect.

When charge is shared between the first and second load capacitors, the data driving device determines whether a first predetermined time point has arrived (S800). At this time, the first time point refers to the time point when the output voltage of the charge sharing line is output as a transient response.

When the first time point arrives, the data driving device determines whether the open is defective by comparing the output voltage at the first time point with the first reference voltage (S810). The data driving device determines that the open is normal if the output voltage at the first time exceeds the first reference voltage, and determines that the open is defective if the output voltage at the first time is less than the first reference voltage.

Afterwards, the data driving device determines whether a predetermined second time point has arrived (S820). At this time, the second time point refers to the time point when the output voltage of the charge sharing line is output as a steady-state response.

When the second time point arrives, the data driving device compares the output voltage at the second time point with the second reference voltage to determine whether there is a short circuit (S830). The data driving device determines that the short is normal if the output voltage at the second time is the same as the second reference voltage, and determines that the short is defective if the output voltage at the second time is different from the second reference voltage.

Referring again to FIG. 7, if it is determined that the data driving device is normally bonded, the bonding resistance value can be determined using the output voltage at the first time (S740). Specifically, the data driving device may determine the bonding resistance value between the data driving device and the display panel as a resistance value mapped to the output voltage at the first point in time, which is a transient response, on a table where bonding resistance values are mapped for each output voltage.

At this time, the bonding resistance value table for each output voltage may be a table in which bonding resistance values according to the slope of the output voltage at the first point of time are mapped. Alternatively, the bonding resistance value table for each output voltage may be a table in which bonding resistance values according to the level of the output voltage at the first point of time are mapped.

If the data driving device determines that there is an open failure or a short circuit, it reports it to the user and blocks the data voltage supplied to the data lines when operating in display mode.

Those skilled in the art to which the present invention pertains will understand that the above-described present invention can be implemented in other specific forms without changing its technical idea or essential features.

For example, all of the disclosed methods and procedures described herein can be implemented, at least in part, using one or more computer programs or components. This component may be stored in a series of formats via any conventional computer-readable or machine-readable medium, including volatile and non-volatile memory such as RAM, ROM, flash memory, magnetic or optical disks, optical memory, or other storage media. Can be provided as computer instructions. The directives may be provided as software or firmware, and may be implemented, in whole or in part, in hardware configurations such as ASICs, FPGAs, DSPs, or any other similar device. The instructions may be configured to be executed by one or more processors or other hardware components, which, when executing the set of computer instructions, may perform all or part of the methods and procedures disclosed herein. enable it to be performed.

Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

100: display device 110: display panel
120: circuit board 130: timing control unit
140: circuit board 150: flexible film
200: Data driving device for determining bonding defects

Claims (15)

a first channel processing unit that supplies a first level voltage to a first data line to charge a first load capacitor of the first data line;
a second channel processing unit that supplies a second level voltage to a second data line to charge a second load capacitor of the second data line;
a channel mux connecting the first channel processing unit to the first data line and connecting the second channel processing unit to the second data line;
a first switch selectively connecting the first data line and the second data line;
a charge sharing line through which charges charged in the first and second load capacitors are shared with each other when the first switch is turned on;
a control unit that controls the channel mux and the first switch; and
Determining bonding defects, comprising a comparator that compares the output voltage of the charge sharing line with a reference voltage and outputs a comparison voltage indicating whether the bonding between the data driving device and the display panel is defective,
Data for determining bonding defects, wherein the first level voltage is a level voltage corresponding to the maximum gray level among a plurality of gray levels, and the second level voltage is a voltage corresponding to the minimum gray level among the plurality of gray levels. Drive device. According to paragraph 1,
When the charging of the first and second load capacitors is completed, the control unit turns on the first switch so that the charges charged in the first and second load capacitors are shared with each other through the charge sharing line, and for a predetermined time. When this has elapsed, turn off the first switch,
The data driving device for determining bonding defects, wherein the comparator compares the output voltage with a reference voltage and outputs the comparison voltage when the first switch is turned on. According to paragraph 2,
The control unit turns on the channel mux to charge the first load capacitor with the voltage of the first level, causes the second load capacitor to be charged with the voltage of the second level, and turns on the first switch. A data driving device for determining bonding defects, characterized in that the channel mux is turned off when the channel mux is turned off. a first channel processing unit that supplies a first level voltage to a first data line to charge a first load capacitor of the first data line;
a second channel processing unit that supplies a second level voltage to a second data line to charge a second load capacitor of the second data line;
a channel mux connecting the first channel processing unit to the first data line and connecting the second channel processing unit to the second data line;
a first switch selectively connecting the first data line and the second data line;
a charge sharing line through which charges charged in the first and second load capacitors are shared with each other when the first switch is turned on;
a control unit that controls the channel mux and the first switch; and
Determining a bonding defect, comprising a comparator that compares the output voltage of the charge sharing line with a reference voltage and outputs a comparison voltage indicating whether the bonding between the data driving device and the display panel is defective,
When the charging of the first and second load capacitors is completed, the control unit turns on the first switch so that the charges charged in the first and second load capacitors are shared with each other through the charge sharing line, and for a predetermined time. When this has elapsed, turn off the first switch,
When the first switch is turned on, the comparator compares the output voltage with a reference voltage and outputs the comparison voltage,
The control unit turns on the channel mux to charge the first load capacitor with the voltage of the first level, causes the second load capacitor to be charged with the voltage of the second level, and turns on the first switch. When this happens, turn off the channel mux,
It further includes a ground switch for initializing the first and second load capacitors by connecting the first and second load capacitors to a ground terminal,
The control unit initializes the first and second load capacitors by turning on the first switch and the ground switch, and turns off the first switch and the ground switch when the channel mux is turned on. A data driving device that determines. According to paragraph 2,
The comparator is
To determine whether there is an open defect, the first comparison voltage is output by comparing the first output voltage at the first time point, which is a transient response, with the first reference voltage, and to determine whether there is a short circuit defect, the first comparison voltage is output at the second time point, which is a steady state response. 2 A data driving device for determining bonding defects, characterized in that it outputs a second comparison voltage by comparing the output voltage with a second reference voltage. According to clause 5,
The comparator outputs a high-level first comparison voltage indicating an open failure when the first output voltage is less than the first reference voltage, and outputs a high level first comparison voltage indicating a short circuit failure when the second output voltage is different from the second reference voltage. A data driving device for determining bonding defects, characterized in that it outputs a second comparison voltage of the level. According to paragraph 1,
The bonding resistance value between the data driving device and the display panel is determined at the first time point as a transient response on the table where the bonding resistance value is mapped for each output voltage when the bonding between the data driving device and the display panel is determined to be normal. 1 A data driving device that determines bonding defects, characterized in that it is determined by the resistance value mapped to the output voltage. delete a first channel processing unit that supplies a first level voltage to a first data line to charge a first load capacitor of the first data line;
a second channel processing unit that supplies a second level voltage to a second data line to charge a second load capacitor of the second data line;
a channel mux connecting the first channel processing unit to the first data line and connecting the second channel processing unit to the second data line;
a first switch selectively connecting the first data line and the second data line;
a charge sharing line through which charges charged in the first and second load capacitors are shared with each other when the first switch is turned on;
a control unit that controls the channel mux and the first switch; and
Determining a bonding defect, comprising a comparator that compares the output voltage of the charge sharing line with a reference voltage and outputs a comparison voltage indicating whether the bonding between the data driving device and the display panel is defective,
The charge sharing line further includes an external capacitor line connected to an external capacitor,
The data driving device for determining bonding defects, wherein the external capacitor shares charge with the first and second load capacitors to reduce the output voltage increase rate of the charge sharing line. According to clause 9,
A data driving device for determining bonding failure, wherein the external capacitor has a capacitance greater than the capacitance of the first and second load capacitors. a first load capacitor connected to the first data line and charged to a first level voltage;
a second load capacitor connected to the second data line and charged with a second level voltage;
a charge sharing line connected to the first and second data lines to share the charges charged in the first and second load capacitors when the charging of the first and second load capacitors is completed; and
A display device for determining bonding defects, comprising a determination unit that determines whether bonding between a data driving device and a display panel is defective using the output voltage of the charge sharing line. According to clause 11,
The judgment department,
The first output voltage at the first time point, which is a transient response, is compared with the first reference voltage, and if the first output voltage is lower than the first reference voltage, it is determined to be an open failure, and the second output voltage at the second time point, which is a steady-state response, is determined to be open. A display device for determining a bonding defect, characterized in that it compares with a second reference voltage and determines a short circuit if the second output voltage is different from the second reference voltage. According to clause 11,
The judgment department,
If it is determined that the bonding between the data driving device and the display panel is normal, the bonding resistance value between the data driving device and the display panel is calculated at the first time point, which is a transient response, on a table in which bonding resistance values are mapped for each output voltage. 1 A display device for determining bonding defects, characterized in that it is determined by the resistance value mapped to the output voltage. According to clause 11,
It further includes a ground switch that connects the charge sharing line to a ground terminal to initialize the first and second load capacitors,
The ground switch is,
A display device for determining bonding failure, characterized in that the first load capacitor and the second load capacitor are initialized by connecting the charge sharing line to a ground terminal before the first load capacitor and the second load capacitor are charged. According to clause 11,
A display for determining bonding defects, wherein the first level voltage is a level voltage corresponding to the maximum gray level among a plurality of gray levels, and the second level voltage is a voltage corresponding to the minimum gray level among the plurality of gray levels. Device.

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