Lamp panel and display screen

Abstract

The embodiment of the utility model provides a lamp panel and a display screen, and relates to the technical field of display. The lamp panel monitors the state of the lamp panel in real time through current detection. The lamp panel comprises a plurality of light emitting diodes and a detection circuit; the plurality of light-emitting diodes are arranged in a plurality of columns; the detection circuit is electrically connected with the plurality of light emitting diodes; the detection circuit comprises a logic control module, a gating module and a comparison module, the first end of the logic control module is electrically connected with the first end of the light-emitting diode, and the second end of the logic control module is electrically connected with the second end of the light-emitting diode; the gating module is provided with a plurality of input ends, and one input end is connected with the first end of each light emitting diode in a column of light emitting diodes; the first input end of the comparison module is electrically connected with the output end of the gating module, and the second input end of the comparison module is electrically connected with the reference end; the comparison module is configured to compare the magnitude of signals received by the first input end and the second input end and output a judgment signal.

Description

Technical Field

[0001] The utility model relates to the field of display technology, in particular to a light board and a display screen. Background Art

[0002] As LED display screens become larger and denser, the number of light groups distributed on them also becomes huge. In order to facilitate monitoring of the working status and display life of the LED light groups, it is necessary to add a monitoring function for the LED light groups to the display chip.

[0003] LED lights are essentially devices with high luminous efficiency. The brightness they produce depends on the current flowing through the LED beads. Currently, in the field of LED applications, existing monitoring systems for LED light sets on the market have functions such as open circuit detection, short circuit detection, and premature death detection. However, these essentially measure the LED voltage and cannot effectively reflect the actual condition of the LED. Utility Model Content

[0004] The embodiment of the utility model provides a light board and a display screen, wherein the light board monitors the state of the light board in real time through current detection.

[0005] In a first aspect, some embodiments of the present application provide a light board comprising: a plurality of light-emitting diodes and a detection circuit; the plurality of light-emitting diodes are arranged into a plurality of columns; the detection circuit is electrically connected to the plurality of light-emitting diodes; the detection circuit is configured to detect whether the light-emitting diodes are damaged; the detection circuit comprises: a logic control module, a selection module and a comparison module.

[0006] The first end of the logic control module is electrically connected to the first end of the light-emitting diode, and the second end of the logic control module is electrically connected to the second end of the light-emitting diode; the selection module is provided with multiple input ends, and one of the input ends is connected to the first end of each light-emitting diode in a column of light-emitting diodes; the first input end of the comparison module is electrically connected to the output end of the selection module, and the second input end of the comparison module is electrically connected to the reference end.

[0007] The logic control module is configured to pull down the potential of the first end of the light-emitting diode to a first level, and pull up the potential of the second end of the light-emitting diode to a second level, so that the light-emitting diode outputs a reverse bias current to the corresponding input end of the selection module; and controls the corresponding input end and output end of the selection module to be connected, so that the reverse bias current is transmitted to the first input end of the comparison module; the second level is greater than the first level; the comparison module is configured to compare the sizes of the signals received by the first input end and the second input end, and output a judgment signal.

[0008] Based on the above scheme, some embodiments of the present application provide a light board that uses a detection circuit to detect whether a light-emitting diode is damaged. A logic control module is used to provide a reverse voltage to the light-emitting diode, thereby generating a reverse bias current and controlling the connection between the corresponding input and output terminals of the selection module to transmit the reverse bias current to the comparison module. The comparison module compares the voltage to obtain a judgment signal, and uses the judgment signal to determine whether the light-emitting diode is damaged. Current detection can more accurately reflect the condition of the light-emitting diode and monitor the life of the light board in real time.

[0009] In some embodiments, the comparison module includes: a comparator; a first input terminal of the comparator is the first input terminal of the comparison module, and a second input terminal of the comparator is the second input terminal of the comparison module.

[0010] In some embodiments, the comparator is a current comparator; the reference end is configured to provide a reference current, which is the threshold current of the light-emitting diode; the comparator is configured to compare the current value of the reverse bias current and the current value of the reference current, and output the judgment signal; wherein the threshold current of the light-emitting diode refers to the maximum current allowed to pass in the reverse direction.

[0011] In some embodiments, the comparator is a voltage comparator, and the comparison module further includes: a first resistor; a first end of the first resistor is connected to the first input end of the comparator, and a second end of the first resistor is connected to the ground end.

[0012] The reverse bias current is converted into a first voltage via the first resistor, and the reference end is configured to provide a reference voltage; the reference voltage is the product of the current value of the threshold current of the light-emitting diode and the resistance value of the first resistor; wherein the threshold current of the light-emitting diode refers to the maximum current allowed to pass in the reverse direction; the comparison module is configured to compare the voltage value of the first voltage with the voltage value of the reference voltage, and output the judgment signal.

[0013] In some embodiments, the gating module includes: multiple gating circuits, each of the gating circuits corresponds to a column of light-emitting diodes; a first end of the gating circuit is electrically connected to a first end of the light-emitting diode in the corresponding column, and a second end of the gating circuit is electrically connected to a first input end of a comparison module; a control end of the gating circuit is electrically connected to a third end of the logic control module; and the gating circuit is configured to be turned on when detecting a corresponding column of light-emitting diodes.

[0014] In some embodiments, the gating circuit includes a gating transistor; the control end of the gating transistor is the control end of the gating circuit, the first end of the gating transistor is the first end of the gating circuit, and the second end of the gating transistor is the second end of the gating circuit.

[0015] In some embodiments, the light board further includes: a plurality of first transistors; the control end of the first transistor is electrically connected to the first control end of the logic control module, the first end of the first transistor is electrically connected to the voltage end, and the second end of the first transistor is electrically connected to the first end of the light-emitting diode of the corresponding column.

[0016] In some embodiments, the multiple light-emitting diodes are arranged in multiple rows, and the light board further includes: multiple second transistors; the control end of the second transistor is electrically connected to the second control end of the logic control module, the first end of the second transistor is electrically connected to the second end of the light-emitting diode in the corresponding row, and the second end of the second transistor is electrically connected to the ground end.

[0017] In some embodiments, the light board further includes: a plurality of current sources; a first end of the current source is electrically connected to the voltage end, and a second end of the current source is electrically connected to a first end of the first transistor of a corresponding column.

[0018] In a second aspect, some embodiments of the present application further provide a display screen comprising the above-mentioned light board.

[0019] The beneficial effects of the display screen are the same as those of the above-mentioned light board, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0021] Figure 1 A schematic diagram of a light board structure provided in an embodiment of the present application;

[0022] Figure 2 A schematic diagram of another light panel structure provided in an embodiment of the present application;

[0023] Figure 3 A schematic diagram of a common cathode connection method of a light panel provided in an embodiment of the present application;

[0024] Figure 4 A schematic diagram of a common anode connection method for light panels provided in an embodiment of the present application;

[0025] Figure 5 A schematic diagram of a comparison module provided in an embodiment of the present application;

[0026] Figure 6 A schematic diagram of a comparator provided in an embodiment of the present application is a current comparator;

[0027] Figure 7 A schematic diagram of a comparator provided in an embodiment of the present application is a voltage comparator;

[0028] Figure 8 A schematic diagram of a gating circuit provided in an embodiment of the present application;

[0029] Figure 9 A schematic diagram of another light panel structure provided in an embodiment of the present application;

[0030] Figure 10 This is a structural block diagram of a display screen provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this utility model, unless otherwise specified, "plurality" means two or more.

[0034] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "connected" and "connect" should be understood broadly. For example, they can refer to fixed connections, removable connections, or integral connections. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances. Furthermore, when describing pipelines, the terms "connected" and "connected" in this utility model have the meaning of conducting electricity. The specific meaning should be understood in the context.

[0035] In the embodiments of the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present invention should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0036] As described in the background technology, as LED display screens become larger and denser, the number of light groups distributed on them also becomes huge. In order to facilitate monitoring of the working status and display life of the LED light groups, it is necessary to add a monitoring function for the LED light groups in the display chip.

[0037] LED lights are essentially devices with high luminous efficiency. The brightness they produce depends on the current flowing through the LED beads. Currently, in the field of LED applications, existing monitoring systems for LED light sets on the market have functions such as open circuit detection, short circuit detection, and premature death detection. However, these essentially measure the LED voltage and cannot effectively reflect the actual condition of the LED.

[0038] For example, to support the bad pixel detection function, it is actually necessary to detect the voltage of the channel to obtain the specific channel status. The general specific solution is:

[0039] After starting the bad pixel detection function, the driver chip outputs a small current of uA level through the channel control unit, and then determines the on-off status of the channel by detecting the voltage of the channel. When the channel is open, the current cannot be output at this time, and the detected voltage value is small. At this time, a voltage threshold is set, generally between 0.3V and 0.5V. This voltage threshold can be configured in levels through registers, depending on the actual circuit design of the driver chip. When the detection voltage is less than this voltage threshold, we consider that this channel is open. By the same principle, when the channel is short-circuited, we can determine whether the channel is in a short-circuit state by judging the detection voltage and the short-circuit voltage threshold. When the channel voltage is greater than the detection voltage threshold, it is considered that there is an LED short circuit in this channel.

[0040] As can be seen from the above description, the existing technology mainly determines the operating status of LED lamps by detecting channel voltage. However, LED lamps are essentially overcurrent devices. The brightness of LED lamps depends on the current flowing through the LED lamp beads. It is actually inaccurate to determine the status of LED lamps by detecting the voltage status.

[0041] At the same time, the driver chip generally provides a maximum of four voltage threshold levels for configuration. This means that the voltage threshold needs to be manually adjusted. Moreover, in some modules with large external parasitic capacitance, adjusting the voltage threshold level cannot meet the judgment of the on-off condition, which will lead to false detection. At the same time, the detection judgment at this time cannot accurately reflect the actual working status of the LED lamp, and only provides a basic detection method.

[0042] Based on this, the embodiment of the present application provides a light board. Figure 1 As shown, the light board 100 includes: a plurality of light emitting diodes 10 and a detection circuit 20; wherein the plurality of light emitting diodes 10 are arranged in a plurality of columns.

[0043] The detection circuit 20 is electrically connected to the plurality of light emitting diodes 10 ; the detection circuit 20 is configured to detect whether the light emitting diodes 10 are damaged.

[0044] The detection circuit 20 provides a reverse voltage to the light emitting diode 10 .

[0045] For example, the light emitting diode is forward-conducting, that is, when the light emitting diode is working normally, the positive electrode voltage of the light emitting diode is greater than the negative electrode voltage; and the current of the negative electrode will not be transmitted to the positive electrode, which is in the cut-off state.

[0046] LED damage generally refers to reverse breakdown, meaning that the current at the negative terminal is transferred to the positive terminal. Therefore, the detection circuit applies a reverse voltage to the LED, which does not break down the LED. Ideally, if the LED is intact, no current or voltage will be detected. If current or voltage is detected, it can be determined that the LED is damaged.

[0047] The detection circuit 20 includes a logic control module 21 , a strobe module 22 and a comparison module 23 .

[0048] It should be noted that, for example, 11-12 in the drawings of this application indicates that component 11 belongs to component 12, and for example, 21-20 indicates that logic control module 21 belongs to detection circuit 20. Other similar reference numerals in the drawings also follow the above description.

[0049] The first end 211 of the logic control module 21 is electrically connected to the first end 101 of the light emitting diode 10 , and the second end 212 of the logic control module 21 is electrically connected to the second end 102 of the light emitting diode 10 .

[0050] The strobe module 22 is provided with a plurality of input terminals 220, one of which is connected to the first terminal 101 of each LED 10 in a column of LEDs 10. The third terminal 213 of the logic control module 21 is electrically connected to the control terminal 221 of the strobe module 22.

[0051] The first input terminal 231 of the comparison module 23 is electrically connected to the output terminal OUT of the selection module 22 , and the second input terminal 232 of the comparison module 23 is electrically connected to the reference terminal REF.

[0052] The logic control module 21 is configured to pull down the potential of the first end 101 of the light-emitting diode 10 to a first level and pull up the potential of the second end 102 of the light-emitting diode 10 to a second level, so that the light-emitting diode 10 outputs a reverse bias current to the input end of the corresponding connected selection module 22.

[0053] The logic control module 21 is also configured to control the input terminal 220 corresponding to the selection module 22 to be connected to the output terminal OUT so that the reverse bias current is transmitted to the first input terminal 231 of the comparison module 23; the comparison module 23 is configured to compare the sizes of the signals received by the first input terminal 231 and the second input terminal 232, and output a judgment signal.

[0054] It should be noted that ideally, no current flows during reverse bias in an LED. However, due to process factors, a threshold current I exists, which is the maximum allowable reverse bias current. Within this threshold current, the LED is considered normal and undamaged. If it exceeds this threshold current, the LED has experienced reverse breakdown and is damaged.

[0055] like Figure 2 As shown, in some embodiments, the first end 101 of the light emitting diode 10 is an anode, and the second end of the light emitting diode 10 is a cathode. The second level is greater than the first level.

[0056] That is, the logic control module 21 pulls down the potential of the anode of the light-emitting diode 10 to a first level, so that it is in a low voltage state and is lower than the breakdown voltage of the light-emitting diode and the voltage threshold U, and then releases the pull-down, so that the anode of the light-emitting diode is in a floating state.

[0057] For example, the second level is a high level, the first level is a low level, and the second level is less than a breakdown voltage of the light emitting diode.

[0058] The logic control module 21 pulls down the potential of the positive electrode of the light-emitting diode 10 to a first level, and pulls up the potential of the negative electrode of the light-emitting diode 10 to a second level. Since the second level is a high level and the first level is a low level, the light-emitting diode 10 will not be turned on at this time, is in an off state, and will not emit light.

[0059] In this way, the light-emitting diode generates a reverse bias current If, which is transmitted to the input terminal 220 of the selection module 22; the logic control module 21 connects the corresponding input terminal 220 with the output terminal OUT, and transmits the reverse bias current If to the first input terminal 231 of the comparison module 23.

[0060] The comparison module 23 compares the magnitudes of the signals received by the first input terminal 231 and the second input terminal 232 and outputs a determination signal. When the reference terminal outputs a threshold current I, the comparison module 23 compares the magnitudes of the reverse bias current If with the threshold current I. If the determination signal output by the comparison module 23 is high, it indicates that the reverse bias current If is greater than the threshold current I, and the light-emitting diode is damaged. If the determination signal output by the comparison module 23 is low, it indicates that the reverse bias current If is less than the threshold current I, and the light-emitting diode is in a normal state and is not damaged.

[0061] When the reference end outputs the voltage threshold U, the comparison module 23 compares the reverse bias voltage Uf with the voltage threshold U. If the judgment signal output by the comparison module 23 is a high level, it means that the reverse bias voltage Uf is greater than the voltage threshold U, and the light-emitting diode is in a damaged state. If the judgment signal output by the comparison module 23 is a low level, it means that the reverse bias voltage Uf is less than the voltage threshold U, and the light-emitting diode is in a normal state and is not damaged.

[0062] The voltage threshold U refers to the product of the threshold current I and the resistance R, and the reverse bias voltage Uf refers to the product of the reverse bias current If and the resistance R.

[0063] It should be noted that the above description is only for the detection of one light-emitting diode. A column of light-emitting diodes corresponds to a path connecting an input end and an output end in a selection module. Among them, there are multiple light-emitting diodes in a column of light-emitting diodes. The logic control module will apply a reverse voltage to both ends of the light-emitting diode to be detected to detect whether it is damaged; the remaining light-emitting diodes are still in normal working condition.

[0064] After the logic control module 21 connects the first input terminal 220 to the output terminal OUT, the logic control module 21 sequentially detects the LEDs until the first column of LEDs is detected. Then, after the logic control module 21 connects the second input terminal 220 to the output terminal OUT, the logic control module 21 sequentially detects the LEDs until the second column of LEDs is detected. This process is repeated in this manner until multiple columns of LEDs are detected.

[0065] like Figure 2 and Figure 3 As shown, in some embodiments, a plurality of light emitting diodes are arranged in an array. Figure 3 FIG shows N rows and N columns of light-emitting diodes. In the first row, the cathodes (negative electrodes) of the N light-emitting diodes are connected together, which is called a common cathode connection. Figure 3 The arrows in the diagram indicate the direction of current flow.

[0066] That is, the logic control module 21 pulls down the potential of the anode of the LED 10 to a first level, placing it in a low voltage state and below the breakdown voltage of the LED and the voltage threshold U. The pull-down is then released, leaving the anode of the LED in a floating state. For example, the second level is a high level, the first level is a low level, and the second level is less than the breakdown voltage of the LED.

[0067] The logic control module 21 pulls down the potential of the positive electrode of the light-emitting diode 10 to a first level, and pulls up the potential of the negative electrode of the light-emitting diode 10 to a second level. Since the second level is a high level and the first level is a low level, the light-emitting diode 10 will not be turned on at this time, is in an off state, and will not emit light.

[0068] In this way, the light-emitting diode generates a reverse bias current If, which is transmitted to the input terminal 220 of the selection module 22 via the first column line; the logic control module 21 connects the corresponding input terminal 220 with the output terminal OUT and transmits the reverse bias current If to the first input terminal 231 of the comparison module 23.

[0069] The comparison module 23 compares the magnitudes of the signals received by the first input terminal 231 and the second input terminal 232 and outputs a determination signal. When the reference terminal outputs a threshold current I, the comparison module 23 compares the magnitudes of the reverse bias current If with the threshold current I. If the determination signal output by the comparison module 23 is high, it indicates that the reverse bias current If is greater than the threshold current I, and the light-emitting diode is damaged. If the determination signal output by the comparison module 23 is low, it indicates that the reverse bias current If is less than the threshold current I, and the light-emitting diode is in a normal state and is not damaged.

[0070] When the reference end outputs the voltage threshold U, the comparison module 23 compares the reverse bias voltage Uf with the voltage threshold U. If the judgment signal output by the comparison module 23 is a high level, it means that the reverse bias voltage Uf is greater than the voltage threshold U, and the light-emitting diode is in a damaged state. If the judgment signal output by the comparison module 23 is a low level, it means that the reverse bias voltage Uf is less than the voltage threshold U, and the light-emitting diode is in a normal state and is not damaged.

[0071] The voltage threshold U refers to the product of the threshold current I and the resistance R, and the reverse bias voltage Uf refers to the product of the reverse bias current If and the resistance R.

[0072] Similarly, if Figure 2 and Figure 4 As shown, in some embodiments, a plurality of light emitting diodes are arranged in an array. Figure 4 FIG shows N rows and N columns of light-emitting diodes. In the first row, the anodes (positive electrodes) of the N light-emitting diodes are connected together, which is called a common anode connection. Figure 4The arrows in the diagram indicate the direction of current flow.

[0073] The specific detection process is the same as described above and will not be repeated here. It should be noted that the reverse voltage provided by the logic control module to the LED also acts on the column line. This generates a corresponding current on the column line, which is the reverse bias current If described above. Therefore, by comparing the reverse bias current If with the threshold current I, it is possible to detect whether the LED is damaged.

[0074] The subsequent description of the above detection circuit is all explained in a common cathode connection manner.

[0075] Based on the above scheme, some embodiments of the present application provide a light board that uses a detection circuit to detect whether a light-emitting diode is damaged. A logic control module is used to provide a reverse voltage to the light-emitting diode, thereby generating a reverse bias current and controlling the connection between the corresponding input and output terminals of the selection module to transmit the reverse bias current to the comparison module. The comparison module compares the voltage to obtain a judgment signal, and uses the judgment signal to determine whether the light-emitting diode is damaged. Current detection can more accurately reflect the condition of the light-emitting diode and monitor the life of the light board in real time.

[0076] like Figure 5 As shown, the comparison module 23 includes a comparator 24 .

[0077] The first input terminal of the comparator 24 is the first input terminal 231 of the comparison module 23 , and the second input terminal of the comparator 24 is the second input terminal 232 of the comparison module 23 .

[0078] That is, the comparator 24 compares the signal at the reference terminal with the signal at the first input terminal.

[0079] like Figure 6 As shown, the comparator 24 is a current comparator 24I; the reference terminal REF is configured to provide a reference current, and the reference current IREF is the threshold current I of the light emitting diode 10 .

[0080] The comparator 24 is configured to compare the current value of the reverse bias current If with the current value of the reference current IREF and output a determination signal. The threshold current of the light emitting diode 10 refers to the maximum current allowed to pass in the reverse direction.

[0081] The comparator 24 compares the current value of the reverse bias current If with the current value of the reference current IREF. If the judgment signal output by the comparator 24 is a high level, it means that the current value of the reverse bias current If is greater than the current value of the reference current IREF, and the light-emitting diode is in a damaged state. If the judgment signal output by the comparator 24 is a low level, it means that the current value of the reverse bias current If is less than the current value of the reference current IREF, and the light-emitting diode is in a normal state and is not damaged.

[0082] like Figure 7 As shown, the comparator 24 is a voltage comparator, and the comparison module 23 further includes: a first resistor R1.

[0083] A first end of the first resistor R1 is connected to the first input end of the comparator 24 , and a second end of the first resistor R1 is connected to the ground end GND.

[0084] The reverse bias current If is converted into a first voltage U1 via the first resistor R1 , ie, the reverse bias voltage Uf mentioned above; the reference terminal REF is configured to provide a reference voltage VREF, ie, the voltage threshold U mentioned above.

[0085] The reference voltage VREF is the product of the current value of the threshold current of the light-emitting diode 10 and the resistance value of the first resistor R1; wherein the threshold current of the light-emitting diode 10 refers to the maximum current allowed to pass in the reverse direction; the comparison module 23 is configured to compare the voltage value of the first voltage U1 with the voltage value of the reference voltage and output a judgment signal.

[0086] When the reference end outputs the reference voltage VREF, the comparison module 23 compares the first voltage U1 with the reference voltage VREFU. If the judgment signal output by the comparison module 23 is a high level, it means that the first voltage U1 is greater than the reference voltage VREF, and the light-emitting diode is in a damaged state. If the judgment signal output by the comparison module 23 is a low level, it means that the first voltage U1 is less than the reference voltage VREF, and the light-emitting diode is in a normal state and is not damaged.

[0087] It should be noted that the reverse bias current has a small current value and may not be detected by the comparator, so it is amplified by the first resistor. The resistance of the first resistor is large in order to further amplify the current value of the reverse bias current.

[0088] like Figure 8 As shown, the gating module 22 includes a plurality of gating circuits 25 .

[0089] The gating circuit 25 corresponds to a column of light-emitting diodes 10; a first end of the gating circuit 25 is electrically connected to the anode of the light-emitting diodes 10 in the corresponding column, and a second end of the gating circuit 25 is electrically connected to the first input end 231 of the comparison module 23; a control end of the gating circuit 25 is electrically connected to the third end 213 of the logic control module 21; the gating circuit is configured to be turned on when detecting the light-emitting diodes 10 in the corresponding column.

[0090] like Figure 8As shown, the gating circuit 25 includes a gating transistor Qx. The control terminal of the gating transistor Qx is the control terminal of the gating circuit 25 , the first terminal of the gating transistor Qx is the first terminal of the gating circuit, and the second terminal of the gating transistor Qx is the second terminal of the gating circuit 25 .

[0091] The logic control module 21 can control the conduction of the gate transistor Qx, thereby turning on the corresponding gate circuit 25.

[0092] In some embodiments, the gate transistor Qx is a MOS transistor.

[0093] For example, the logic control module 21 can control the gating transistor Qx in the first gating circuit 25 to turn on, thereby turning on the first column of light-emitting diodes; the logic control module 21 then detects each light-emitting diode in the first column in turn until the first column of light-emitting diodes is fully detected; at this time, the logic control module 21 controls the gating transistor Qx in the first gating circuit 25 to turn off, and controls the gating transistor Qx in the second gating circuit 25 to turn on, and the logic control module 21 then detects each light-emitting diode in the second column in turn until the second column of light-emitting diodes is fully detected; and so on, until all the light-emitting diodes on the light board are fully detected.

[0094] It should be noted that when one gating circuit 25 is in the on state, the other gating circuits 25 are in the off state.

[0095] like Figure 9 As shown, the light board 100 further includes: a plurality of first transistors Q1.

[0096] The control end of the first transistor Q1 is electrically connected to the first control end of the logic control module 21 (not shown in the figure), the first end of the first transistor Q1 is electrically connected to the voltage end VCC, and the second end of the first transistor Q1 is electrically connected to the anode of the light-emitting diode 10 in the corresponding column.

[0097] When the light emitting diode operates normally, the logic control module 21 can provide voltage to the anode of the light emitting diode by controlling the conduction of the first transistor Q1 .

[0098] A first transistor Q1 may correspond to a column of light emitting diodes to control whether the path of the column of light emitting diodes is turned on or off, thereby controlling the light emitting diodes to work normally.

[0099] That is to say, when the light-emitting diode is working normally, the logic control module 21 controls the first transistor Q1 to be turned on so that the voltage terminal VCC can supply power to the light-emitting diode, thereby enabling the light-emitting diode to work normally; similarly, the logic control module 21 can also control the first transistor Q1 to be turned off so that the voltage terminal VCC cannot supply power to the light-emitting diode. In this way, the positive terminal of the light-emitting diode does not have the voltage of the voltage terminal VCC, so that the logic control module 21 can pull down the voltage of the positive terminal of the light-emitting diode to facilitate subsequent detection.

[0100] like Figure 9 As shown, a plurality of light emitting diodes 10 are arranged in a plurality of rows, and the light board 100 further includes: a plurality of second transistors Q2.

[0101] The control end of the second transistor Q2 is electrically connected to the second control end of the logic control module 21 (not shown in the figure), the first end of the second transistor Q2 is electrically connected to the cathode of the light-emitting diode 10 in the corresponding row, and the second end of the second transistor Q2 is electrically connected to the ground end GND.

[0102] When the light emitting diode is operating normally, the logic control module 21 can provide a low voltage to the cathode of the light emitting diode by controlling the conduction of the second transistor Q2 , that is, grounding it.

[0103] One second transistor Q2 may correspond to one row of light emitting diodes, thereby controlling whether one row of light emitting diodes can work normally.

[0104] That is, when the light emitting diode is working normally, the logic control module 21 controls the second transistor Q2 to be turned on so that the ground terminal GND can provide a ground voltage to the cathode terminal of the light emitting diode, thereby enabling the light emitting diode to work normally.

[0105] Similarly, the logic control module 21 can also control the second transistor Q2 to be cut off so that the ground terminal GND cannot provide a ground voltage to the negative terminal of the light-emitting diode. In this way, the negative terminal of the light-emitting diode does not have the voltage of the ground terminal GND, so that the logic control module 21 can pull up the voltage of the negative terminal of the light-emitting diode to facilitate subsequent detection.

[0106] For example, the logic control module 21 can control the selection transistor Qx in the first selection circuit 25 to be turned on, so that the first column of light-emitting diodes is connected to the comparison module 23; the logic control module 21 then detects each light-emitting diode in the first column in turn until the first column of light-emitting diodes is completely detected.

[0107] Among them, the logic control module 21 can detect the first light-emitting diode in the first column by controlling the first second transistor Q2 to be turned off; after detecting the first light-emitting diode in the first column, the logic control module 21 controls the first second transistor Q2 to be turned on and controls the second second transistor Q2 to be turned off to detect the second light-emitting diode in the first column; and so on, until the light-emitting diodes in the first column are detected.

[0108] It should be noted that when one second transistor Q2 is turned off, the other second transistors Q2 are all in the on state, that is, the other light emitting diodes are still working normally, and only the light emitting diode to be detected is temporarily in the non-working state.

[0109] like Figure 9 As shown, the light board 100 further includes: a plurality of current sources Id.

[0110] A first terminal of the current source Id is electrically connected to the voltage terminal VCC, and a second terminal of the current source Id is electrically connected to a first terminal of the first transistor Q1 of a corresponding column.

[0111] The current source is used to provide a stable current when the light emitting diode is working normally.

[0112] like Figure 10 As shown, some embodiments of the present application further provide a display screen, wherein the display screen 200 includes the above-mentioned light board 100 .

[0113] Some embodiments of the present application provide a display screen that uses a detection circuit in a light board to detect whether a light-emitting diode (LED) is damaged. A logic control module is used to provide a reverse voltage to the LED, thereby generating a reverse bias current and controlling the connection between the corresponding input and output terminals of a selection module to transmit the reverse bias current to a comparison module. The comparison module then compares the LED to obtain a judgment signal, which is used to determine whether the LED is damaged. Current detection can more accurately reflect the condition of the LED and monitor the life of the light board in real time, further ensuring the display quality of the display screen without affecting the user experience.

[0114] The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited to this. Any changes or replacements within the technical scope disclosed in this utility model should be included in the scope of protection of the present utility model. Therefore, the scope of protection of the present utility model should be based on the scope of protection of the claims.

Claims

1. A light board, characterized in that: include: a plurality of light emitting diodes, wherein the plurality of light emitting diodes are arranged in a plurality of columns; a detection circuit, the detection circuit being electrically connected to the plurality of light emitting diodes; The detection circuit is configured to detect whether the light emitting diode is damaged; the detection circuit includes: a logic control module, wherein a first end of the logic control module is electrically connected to the first end of the light emitting diode, and a second end of the logic control module is electrically connected to the second end of the light emitting diode; a gating module, wherein the gating module is provided with a plurality of input terminals, and one of the input terminals is connected to a first terminal of each light emitting diode in a column of light emitting diodes; a comparison module, wherein a first input terminal of the comparison module is electrically connected to the output terminal of the strobe module, and a second input terminal of the comparison module is electrically connected to a reference terminal; The logic control module is configured to pull down the potential of the first terminal of the light-emitting diode to a first level, and pull up the potential of the second terminal of the light-emitting diode to a second level, so that the light-emitting diode outputs a reverse bias current to the corresponding input terminal of the gating module; and control the corresponding input terminal and output terminal of the gating module to be connected, so that the reverse bias current is transmitted to the first input terminal of the comparison module; The comparison module is configured to compare the magnitudes of the signals received by the first input terminal and the second input terminal, and output a determination signal.

2. The light board according to claim 1, characterized in that: The comparison module includes: a comparator; a first input end of the comparator is the first input end of the comparison module, and a second input end of the comparator is the second input end of the comparison module.

3. The light board according to claim 2, characterized in that: The comparator is a current comparator; the reference terminal is configured to provide a reference current, and the reference current is a threshold current of the light emitting diode; The comparator is configured to compare the current value of the reverse bias current with the current value of the reference current and output the judgment signal; The threshold current of the light emitting diode refers to the maximum current allowed to pass in the reverse direction.

4. The light board according to claim 2, characterized in that: The comparator is a voltage comparator, and the comparison module further includes: a first resistor; A first end of the first resistor is connected to the first input end of the comparator, and a second end of the first resistor is connected to the ground end; The reverse bias current is converted into a first voltage via the first resistor, and the reference terminal is configured to provide a reference voltage; The reference voltage is the product of the current value of the threshold current of the light-emitting diode and the resistance value of the first resistor; wherein the threshold current of the light-emitting diode refers to the maximum current allowed to pass in the reverse direction; The comparison module is configured to compare the voltage value of the first voltage with the voltage value of the reference voltage and output the judgment signal.

5. The light board according to any one of claims 1 to 4, characterized in that: The gating module includes: a plurality of gating circuits, each corresponding to a column of light-emitting diodes; a first end of each gating circuit is electrically connected to a first end of the light-emitting diodes in the corresponding column; a second end of each gating circuit is electrically connected to a first input end of a comparison module; and a control end of each gating circuit is electrically connected to a third end of the logic control module. The gating circuit is configured to be turned on when detecting the light emitting diodes in the corresponding column.

6. The light board according to claim 5, characterized in that: The gating circuit includes a gating transistor; The control end of the gating transistor is the control end of the gating circuit, the first end of the gating transistor is the first end of the gating circuit, and the second end of the gating transistor is the second end of the gating circuit.

7. The light board according to any one of claims 1 to 4, characterized in that: The light board further includes: a plurality of first transistors; The control end of the first transistor is electrically connected to the first control end of the logic control module, the first end of the first transistor is electrically connected to the voltage end, and the second end of the first transistor is electrically connected to the first end of the light emitting diode of the corresponding column.

8. The light board according to claim 7, characterized in that: The plurality of light emitting diodes are arranged in a plurality of rows, and the light board further comprises: a plurality of second transistors; The control end of the second transistor is electrically connected to the second control end of the logic control module, the first end of the second transistor is electrically connected to the second end of the light emitting diode in the corresponding row, and the second end of the second transistor is electrically connected to the ground end.

9. The light board according to claim 8, characterized in that: The light board further includes: a plurality of current sources; A first terminal of the current source is electrically connected to the voltage terminal, and a second terminal of the current source is electrically connected to a first terminal of the first transistor of a corresponding column.

10. A display screen, characterized in that: The invention comprises the light board according to any one of claims 1 to 9.

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