Pixel detection circuit and applicable detection method thereof

Abstract

The invention provides a pixel detection circuit and an applicable detection method thereof, which can effectively detect each light-emitting unit. The pixel detection circuit comprises a plurality of light-emitting units, a switching circuit and a detection circuit. The plurality of light-emitting units are connected in series between the first power supply end and the first reference end. The switching circuit is coupled between a first reference end and a second power supply end. The switching circuit receives a plurality of switching signals. The detection circuit is coupled to the first reference terminal and a second reference terminal among the plurality of light emitting units. The detection circuit receives a plurality of detection signals, and determines whether each light-emitting unit is abnormal in different detection modes based on a plurality of conduction paths flowing through each light-emitting unit or based on a current change message applied with a forward bias voltage and a reverse bias voltage to each light-emitting unit.

Description

Technical Field

[0001] This invention relates to a detection circuit, and more particularly to a pixel detection circuit applicable to multiple cascaded light-emitting units and a suitable detection method thereof. Background Technology

[0002] Generally, a display device includes a pixel circuit composed of multiple pixel units arranged together, and each pixel unit can emit light through a light-emitting element to display a target image. The light-emitting element can be, for example, a light-emitting diode (LED). To reduce the driving current of the pixel circuit, each pixel unit can have multiple light-emitting elements (e.g., two) connected in series. In this way, the pixel circuit can reduce the total current of the display device, thereby efficiently achieving the target brightness.

[0003] However, when multiple connected light-emitting elements fail, the brightness of the display device decreases, causing an overall brightness anomaly. Current detection methods cannot effectively identify which light-emitting element is damaged, making it difficult to continue repairs to eliminate the brightness anomaly. Summary of the Invention

[0004] This invention provides a pixel detection circuit suitable for detecting multiple light-emitting units connected in series, and can effectively detect whether each light-emitting unit is abnormal.

[0005] The pixel detection circuit of this invention includes multiple light-emitting units, a switching circuit, and a detection circuit. The multiple light-emitting units are connected in series between a first power supply terminal and a first reference terminal. The switching circuit is coupled between the first reference terminal and a second power supply terminal. The switching circuit is used to receive multiple switching signals. The detection circuit is coupled between the first reference terminal and a second reference terminal between the multiple light-emitting units. The detection circuit is used to receive multiple detection signals and operates in a first detection mode or a second detection mode.

[0006] In the first detection mode, the switching circuit is turned on. The detection circuit sequentially forms multiple conduction paths through each light-emitting unit based on multiple detection signals, and determines whether each light-emitting unit is abnormal based on whether the light-emitting units emit light in the multiple conduction paths.

[0007] In the second detection mode, the switching circuit and the detection circuit, based on the first power supply voltage at the first power supply terminal and the second power supply voltage at the second power supply terminal, sequentially apply forward bias and reverse bias to each light-emitting unit according to multiple switching signals and multiple detection signals, thereby generating current change information flowing to the integrator coupled to the detection circuit. The detection circuit determines whether each light-emitting unit is abnormal based on the current change information.

[0008] This invention also provides a detection method applicable to pixel detection circuits. The detection method includes the following steps: A detection circuit receives multiple detection signals and operates in a first detection mode or a second detection mode. The detection circuit is coupled to a first reference terminal and a second reference terminal between multiple light-emitting units. The multiple light-emitting units are connected in series between a first power supply terminal and the first reference terminal. A switching circuit receives multiple switching signals. The switching circuit is coupled between the first reference terminal and the second power supply terminal.

[0009] In the first detection mode, the switching circuit is turned on. The detection circuit sequentially forms multiple conduction paths through each light-emitting unit based on multiple detection signals, and determines whether each light-emitting unit is abnormal based on whether it emits light or not in the multiple conduction paths.

[0010] In the second detection mode, the switching circuit and the detection circuit, based on the first power supply voltage at the first power supply terminal and the second power supply voltage at the second power supply terminal, sequentially apply forward bias and reverse bias to each light-emitting unit according to multiple switching signals and multiple detection signals, thereby generating current change information flowing to the integrator coupled to the detection circuit. The detection circuit determines whether each light-emitting unit is abnormal based on the current change information.

[0011] Based on the above, the pixel detection circuit and its applicable detection method of this invention, by setting the detection circuit across multiple light-emitting units, can detect whether each light-emitting unit is abnormal. In the first detection mode, by obtaining the conduction path flowing through each light-emitting unit and the result of whether it emits light, the pixel detection circuit can effectively determine whether each light-emitting unit is abnormal. In the second detection mode, by applying forward bias and reverse bias to each light-emitting unit, the detection circuit can effectively determine whether the open circuit corresponding to the forward bias of each light-emitting unit is abnormal, and can also effectively determine whether the short circuit corresponding to the reverse bias of each light-emitting unit is abnormal, based on the current change information.

[0012] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0013] Figure 1 This is a circuit block diagram of a pixel detection circuit according to an embodiment of the present invention.

[0014] Figure 2 This is a flowchart illustrating a detection method according to an embodiment of the present invention.

[0015] Figure 3 This is a circuit diagram of a pixel detection circuit according to the first embodiment of the present invention.

[0016] Figures 4A to 4B Based on the present invention Figure 3 The illustrated embodiment shows the operation of the pixel detection circuit in the first detection mode.

[0017] Figure 5 Based on the present invention Figure 3 The flowchart shown in the embodiment illustrates the detection method performed by the pixel detection circuit in the first detection mode.

[0018] Figure 6 This is a circuit diagram of a pixel detection circuit according to a second embodiment of the present invention.

[0019] Figures 7A to 7B Based on the present invention Figure 6 The illustrated embodiment shows the operation of the pixel detection circuit in the first detection mode.

[0020] Figure 8 Based on the present invention Figure 6 The flowchart shown in the embodiment illustrates the detection method performed by the pixel detection circuit in the first detection mode.

[0021] Figures 9A to 9D Based on the present invention Figure 6 The embodiment illustrates the operation of the pixel detection circuit in the second detection mode.

[0022] Figure 10 This is a circuit diagram of a pixel detection circuit according to a third embodiment of the present invention.

[0023] Figures 11A to 11B Based on the present invention Figure 10 The illustrated embodiment shows the operation of the pixel detection circuit in the first detection mode.

[0024] Figures 12A to 12D Based on the present invention Figure 10 The embodiment illustrates the operation of the pixel detection circuit in the second detection mode.

[0025] Figure 13 This is a circuit diagram of a pixel detection circuit according to the fourth embodiment of the present invention.

[0026] Figures 14A to 14B Based on the present invention Figure 13 The illustrated embodiment shows the operation of the pixel detection circuit in the first detection mode.

[0027] Figures 15A to 15D Based on the present invention Figure 13 The embodiment illustrates the operation of the pixel detection circuit in the second detection mode.

[0028] In the attached figures, the following labels are used:

[0029] 100, 300, 600, 1000, 1300: Pixel detection circuit

[0030] 110: Multiple light-emitting units

[0031] 120, 320, 620, 1020, 1320: Switching circuits

[0032] 130, 330, 630, 1030, 1330: Detection circuit

[0033] 140, 640, 1040: Integrator

[0034] 321~322, 621~622, 1021~1022, 1321~1322: Switches

[0035] 331~332, 631~632, 1031~1033, 1331~1333: Transistors

[0036] 350: Pixel unit circuit

[0037] AT: Detection signal

[0038] AT1: Detection signal

[0039] AT2: Detection signal

[0040] DR: Second switch signal

[0041] EM: First switch signal, detection signal

[0042] Id1~Id2, Id11~Id12, Id21~Id22: Current

[0043] LED1~LED2: Light-emitting unit

[0044] N1: First reference terminal

[0045] N2: Second reference terminal

[0046] NS1: First power supply terminal

[0047] NS2: Second power supply terminal

[0048] P1~P2: Conduction path

[0049] S2: Multiple detection signals

[0050] S210~S232, S510~S553, S810~S864: Steps

[0051] SEN: Second detection signal

[0052] SW1: Multiple switch signals

[0053] Vdata: Data voltage

[0054] VS1, VDD: First power supply voltage

[0055] VS2, VSS: Second power supply voltage Detailed Implementation

[0056] Some embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Component symbols used in the following description, when appearing in different drawings, are considered to be the same or similar components. These embodiments are only a part of the present invention and do not disclose all possible implementations of the invention. More precisely, these embodiments are merely examples within the scope of the present invention's patent application.

[0057] Figure 1 This is a circuit block diagram of a pixel detection circuit according to an embodiment of the present invention. (See reference) Figure 1 The pixel detection circuit 100 is suitable for detecting the light-emitting operation of multiple light-emitting units connected in series. The multiple light-emitting units are included in a single pixel unit. The pixel detection circuit 100 can detect each pixel unit in the pixel circuit and can effectively detect whether each light-emitting unit in each pixel unit is damaged and unable to emit light. Thus, based on the detection results, the display device using the pixel circuit can repair one or more damaged light-emitting units.

[0058] The pixel detection circuit 100 includes multiple light-emitting units 110, a switching circuit 120, and a detection circuit 130. The multiple light-emitting units 110 may, for example, include two or more light-emitting units LED1 and LED2, and are disposed within a single pixel unit. These light-emitting units LED1~LED2 are connected in series between a first power supply terminal NS1 and a first reference terminal N1. That is, light-emitting unit LED1 is coupled between the first power supply terminal NS1 and a second reference terminal N2, and light-emitting unit LED2 is coupled between the second reference terminal N2 and the first reference terminal N1. The multiple light-emitting units LED1~LED2 may, for example, be implemented using micron-sized light-emitting diodes (MicroLEDs).

[0059] Switching circuit 120 is coupled between first reference terminal N1 and second power supply terminal NS2. Detection circuit 130 has its first terminal coupled to first reference terminal N1 and its second terminal coupled to second reference terminal N2. First power supply terminal NS1 receives first power supply voltage VS1. Second power supply terminal NS2 receives second power supply voltage VS2.

[0060] In a specific detection mode, the pixel detection circuit 100 also includes an integrator 140. The input of the integrator 140 is coupled to the third terminal of the detection circuit 130. The integrator 140 may be implemented, for example, as an integrator in an analog-to-digital converter (ADC).

[0061] Figure 2 This is a flowchart illustrating a detection method according to an embodiment of the present invention. (See reference) Figure 1 as well as Figure 2 The pixel detection circuit 100 executes steps S210~S220 and S231~S232 to detect whether each light-emitting unit LED1~LED2 in a single pixel unit is abnormal.

[0062] In step S210, the switching circuit 120 receives multiple switching signals SW1. The switching circuit 120 is used to perform a switching action according to the multiple switching signals SW1.

[0063] In step S220, the detection circuit 130 receives multiple detection signals S2. The detection circuit 130 is used to perform a switching action based on the multiple detection signals S2, and operates in a first detection mode or a second detection mode.

[0064] The first detection mode can be, for example, a characterization test (CT) mode. In the first detection mode, the detection circuit 130 detects whether each light-emitting unit LED1~LED2 is abnormal or normal. Based on design requirements, the pixel detection circuit 100 can selectively operate in the first detection mode or the second detection mode, or operate in both the first and second detection modes in a time-division manner. Alternatively, when any of the multiple light-emitting units LED1~LED2 is known to be unable to emit light normally and is therefore abnormal, the pixel detection circuit 100 can, for example, selectively operate in the first detection mode.

[0065] In the first detection mode, in step S231, the switching circuit 120 is turned on according to multiple switching signals SW1, so that the first reference terminal N1 and the second power supply terminal NS2 are in a conducting state. Simultaneously, the detection circuit 130 sequentially forms multiple conduction paths P1-P2 flowing through each light-emitting unit LED1-LED2 according to multiple detection signals S2. In conduction path P1 flowing through light-emitting unit LED1, the detection circuit 130 can determine whether the entire light-emitting unit LED1-LED2 is emitting light or not. Then, in conduction path P2 flowing through light-emitting unit LED2, the detection circuit 130 can determine whether the entire light-emitting unit LED1-LED2 is emitting light or not. Thus, the detection circuit 130 determines whether each light-emitting unit LED1-LED2 is abnormal based on whether it is emitting light or not in the multiple conduction paths P1-P2.

[0066] The second detection mode can be, for example, an acceptance test (AT) mode. In the second detection mode, the detection circuit 130 detects whether each light-emitting unit LED1~LED2 is abnormal or normal, and further detects whether the abnormality is an open circuit abnormality or a short circuit abnormality.

[0067] In the second detection mode, in step S232, the switching circuit 120 and the detection circuit 130 operate in concert. Based on the first power supply voltage VS1 and the second power supply voltage VS2, the switching circuit 120 and the detection circuit 130 sequentially apply forward bias and reverse bias to each light-emitting unit LED1~LED2 according to multiple switching signals SW1 and multiple detection signals S2, thereby forming current change information flowing to the integrator 140. The current change information includes the current Id1 generated by the light-emitting unit LED1 under forward bias and the current Id2 generated by the light-emitting unit LED1 under reverse bias. Similarly, the current change information also includes the current Id2 generated by the light-emitting unit LED2 under forward bias and the current Id2 generated by the light-emitting unit LED2 under reverse bias. Thus, the detection circuit 130 determines whether each light-emitting unit LED1~LED2 is abnormal based on the current change information including multiple currents Id1~Id2.

[0068] It is worth mentioning that, since the detection circuit 130 is connected between multiple light-emitting units LED1~LED2, the detection circuit 130 can detect whether each light-emitting unit LED1~LED2 is abnormal. In the first detection mode, by detecting the multiple conduction paths P1~P2 flowing through each light-emitting unit LED1~LED2 and whether they are emitting light, the pixel detection circuit 100 can quickly and effectively determine whether each light-emitting unit LED1~LED2 is abnormal.

[0069] Furthermore, in the second detection mode, the pixel detection circuit 100 can effectively determine whether each light-emitting unit LED1-LED2 is open-circuited based on the current change information generated by each light-emitting unit LED1-LED2 under a forward bias applied by the detection circuit 130. Similarly, the pixel detection circuit 100 can effectively determine whether each light-emitting unit LED1-LED2 is short-circuited based on the current change information generated by each light-emitting unit LED1-LED2 under a reverse bias applied by the detection circuit 130.

[0070] Figure 3 This is a circuit diagram of a pixel detection circuit according to the first embodiment of the present invention. (See reference) Figure 3 In the first embodiment, the pixel detection circuit 300 includes a plurality of light-emitting units LED1~LED2, a switching circuit 320, and a detection circuit 330.

[0071] In display applications, the switching circuit 320 is also coupled to the pixel unit circuit 350. The switching circuit 320, the pixel unit circuit 350, and the multiple light-emitting units LED1~LED2 can serve as a single pixel unit. The switching circuit 320 can serve as a driving circuit for driving the multiple light-emitting units LED1~LED2. Depending on design requirements, the pixel unit circuit 350 can serve as a circuit for resetting, compensating, and other coordinated driving operations.

[0072] In detection applications, the switching circuit 320 can be used as a circuit to perform switching actions to control the conduction state between the first reference terminal N1 and the second power supply terminal NS2. The switching circuit 320 receives the second switching signal DR (Driving TFT) and / or the first switching signal EM through the pixel unit circuit 350 as control signals for switching actions.

[0073] exist Figure 3 In this embodiment, the plurality of light-emitting units LED1~LED2 include a first light-emitting unit LED1 (hereinafter referred to as light-emitting unit LED1) and a second light-emitting unit LED2 (hereinafter referred to as light-emitting unit LED2). The anode of light-emitting unit LED1 is coupled to a first power supply terminal NS1 to receive a first power supply voltage VDD. The cathode of light-emitting unit LED1 is coupled to a second reference terminal N2. The anode of light-emitting unit LED2 is coupled to the second reference terminal N2. The cathode of light-emitting unit LED2 is coupled to the first reference terminal N1.

[0074] The switching circuit 320 includes a first switch 321 (hereinafter referred to as switch 321) and a second switch 322 (hereinafter referred to as switch 322). These switches 321-322 can be implemented, for example, as p-type metal-oxide-semiconductor field-effect transistors (PMOSFETs). The control terminal (i.e., gate) of switch 321 receives a first switching signal EM. The first terminal (e.g., source) of switch 321 is coupled to a first reference terminal N1. The second terminal (e.g., drain) of switch 321 is coupled to the first terminal (e.g., source) of switch 322. The control terminal (i.e., gate) of switch 322 receives a second switching signal DR. The second terminal (e.g., drain) of switch 322 is coupled to a second power supply terminal NS2 to receive a second power supply voltage VSS.

[0075] The detection circuit 330 includes a first transistor 331 (hereinafter referred to as transistor 331) and a second transistor 332 (hereinafter referred to as transistor 332). These transistors 331-332 may be implemented, for example, as a PMOSFET. The control terminal (i.e., gate) of transistor 331 receives a first detection signal AT (hereinafter referred to as detection signal AT). The first terminal (e.g., source) of transistor 331 is coupled to a second reference terminal N2. The second terminal (e.g., drain) of transistor 331 is coupled to a first reference terminal N1. The control terminal (i.e., gate) of transistor 332 receives a second detection signal SEN (hereinafter referred to as detection signal SEN). The first terminal (e.g., source) of transistor 332 is coupled to the first reference terminal N1. The second terminal (e.g., drain) of transistor 332 receives a data voltage Vdata.

[0076] In this embodiment, the first switch signal EM, the second switch signal DR, the detection signal AT, and the detection signal SEN are multiple independent switch signals that switch between logic high and logic low to turn on or off the corresponding switches 321-322 and transistors 331-332. The data voltage Vdata can be, for example, a voltage with a fixed value greater than 0V.

[0077] Figures 4A to 4B Based on the present invention Figure 3 The illustrated embodiment shows the operation of the pixel detection circuit in the first detection mode. Figure 5 Based on the present invention Figure 3 The flowchart illustrating the detection method performed by the pixel detection circuit in the first detection mode is shown in the embodiment. (Refer to...) Figures 4A to 4B as well as Figure 5The pixel detection circuit 300 executes steps S510~S540 and S551~S553 to detect whether each light-emitting unit LED1~LED2 in a single pixel unit is abnormal in the first detection mode, and illustrates the implementation details of step S231.

[0078] In the first detection mode, the first power supply voltage VDD has a first voltage value. The second power supply voltage VSS has a second voltage value. The first voltage value is greater than the second voltage value, and may be, for example, 10V. The second voltage value is greater than or equal to 0, and may be, for example, 0V.

[0079] In step S510, as Figure 4A As shown, switches 321-322 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 331 is turned on according to the detection signal AT. Transistor 332 is turned off according to the detection signal SEN. Thus, a conduction path P1 is formed through the light-emitting unit LED1. The conduction path P1 can be, for example,... Figure 1 One of the multiple conduction paths P1~P2 shown, and may be, for example, the first conduction path flowing through the first power supply terminal NS1, the light-emitting unit LED1, the second reference terminal N2, the transistor 331, the first reference terminal N1, the switching circuit (including multiple switches 321~322), and the second power supply terminal NS2.

[0080] Next, the detection circuit 330 determines whether each of the multiple light-emitting units LED1~LED2 is abnormal based on whether it emits light or not. For example... Figure 4A As shown, assuming the light-emitting unit LED1 is functioning normally, then the conduction path P1 is valid. Conversely, if... Figure 4B As shown, assuming that the light-emitting unit LED1 is abnormal, the conduction path P1 is invalid, and the other conduction path P2 used to flow from the first power supply terminal NS1 through the light-emitting unit LED2 is also invalid.

[0081] Specifically, in step S520, based on the conduction path P1, the detection circuit 330 determines whether multiple light-emitting units LED1~LED2 emit light. When the determination result of step S520 is yes, it indicates that the light-emitting unit LED1 can emit light normally based on the conduction path P1. Since the premise of the first detection mode is that at least one light-emitting unit LED1~LED2 is known to be abnormal, the detection circuit 330 can infer that the light-emitting unit LED2 is abnormal. Thus, in step S531, the detection circuit 330 determines that the abnormality of the pixel unit belongs to abnormality type B, that is, it determines that the light-emitting unit LED1 is normal and the light-emitting unit LED2 is abnormal. In step S532, the light-emitting unit LED2 that was determined to be abnormal is repaired.

[0082] On the other hand, if the judgment result of step S520 is negative, it indicates that the light-emitting unit LED1 cannot emit light normally based on the conduction path P1. Therefore, in step S533, the detection circuit 330 determines that the light-emitting unit LED1 is abnormal. In step S534, the abnormal light-emitting unit LED1 is repaired.

[0083] In step S540, the pixel detection circuit 300 again forms a conduction path P1 for the light-emitting unit LED1 to flow from the first power supply terminal NS1 through the light-emitting unit LED1 in the manner of step S510, and also forms a conduction path P2 for the light-emitting unit LED2 to flow from the first power supply terminal NS1 through the light-emitting unit LED2. Based on the conduction paths P1~P2, the detection circuit 330 determines whether the plurality of light-emitting units LED1~LED2 emit light as a whole.

[0084] When the judgment result of step S540 is yes, it means that the light-emitting unit LED1 can emit light normally based on any one of the conduction paths P1~P2. Since the premise of the first detection mode is that at least one light-emitting unit LED1~LED2 is known to be abnormal, and light-emitting unit LED1 has been judged to be abnormal and repaired, the detection circuit 330 can infer that among the initial multiple light-emitting units LED1~LED2, only light-emitting unit LED1 is abnormal. Thus, in step S551, the detection circuit 330 determines that the abnormality of the pixel unit belongs to abnormality type A, that is, it determines that light-emitting unit LED1 is abnormal and light-emitting unit LED2 is normal.

[0085] On the other hand, if the judgment result of step S540 is negative, it means that the light-emitting unit LED2 cannot emit light normally based on any of the conduction paths P1~P2. Thus, in step S552, the detection circuit 330 determines that the pixel unit's abnormality belongs to abnormality type C, that is, it determines that both light-emitting unit LED1 and light-emitting unit LED2 are abnormal. In step S553, the abnormal light-emitting unit LED2 is repaired.

[0086] Figure 6 This is a circuit diagram of a pixel detection circuit according to a second embodiment of the present invention. (See reference) Figure 6 In the second embodiment, the pixel detection circuit 600 includes a plurality of light-emitting units LED1~LED2, a switching circuit 620, and a detection circuit 630. The plurality of light-emitting units LED1~LED2 and the switching circuit 620 can be referenced from... Figure 3 The relevant descriptions of the embodiments are explained and extrapolated.

[0087] exist Figure 6In this embodiment, the detection circuit 630 includes a first transistor 631 (hereinafter referred to as transistor 631) and a second transistor 632 (hereinafter referred to as transistor 632). These transistors 631-632 may be implemented, for example, as PMOSFETs. The control terminal (i.e., gate) of transistor 631 receives a first detection signal AT (hereinafter referred to as detection signal AT). A first terminal (e.g., source) of transistor 631 is coupled to a second reference terminal N2. A second terminal (e.g., drain) of transistor 631 is coupled to the first reference terminal N1. The control terminal (i.e., gate) of transistor 632 receives a second detection signal SEN (hereinafter referred to as detection signal SEN). A first terminal (e.g., source) of transistor 632 is coupled to the second reference terminal N2. A second terminal (e.g., drain) of transistor 632 receives a data voltage Vdata.

[0088] Figures 7A to 7B Based on the present invention Figure 6 The illustrated embodiment shows the operation of the pixel detection circuit in the first detection mode. Figure 8 Based on the present invention Figure 6 The flowchart illustrating the detection method performed by the pixel detection circuit in the first detection mode is shown in the embodiment. (Refer to...) Figures 7A to 7B as well as Figure 8 The pixel detection circuit 600 executes steps S810~S850 and S861~S864 to detect whether each light-emitting unit LED1~LED2 in a single pixel unit is abnormal in the first detection mode, and illustrates the implementation details of step S231.

[0089] In the first detection mode, the first power supply voltage VDD has a first voltage value or a second voltage value. The second power supply voltage VSS maintains a second voltage value. The first voltage value is greater than the second voltage value, and may be, for example, 10V. The second voltage value is greater than or equal to 0, and may be, for example, 0V.

[0090] In step S810, as Figure 7A As shown, multiple switches 621-622 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 631 is turned on according to the detection signal AT. Transistor 632 is turned off according to the detection signal SEN. In this way, a conduction path P1 is formed through the light-emitting unit LED1. The conduction path P1 can be, for example, a first conduction path passing through the first power supply terminal NS1, the light-emitting unit LED1, the second reference terminal N2, transistor 631, the first reference terminal N1, the switching circuit (including multiple switches 621-622), and the second power supply terminal NS2.

[0091] In step S820, the detection circuit 630 determines whether the multiple light-emitting units LED1~LED2 emit light. Specifically, based on the conduction path P1, the detection circuit 630 determines whether the light-emitting unit LED2 is abnormal based on whether the light-emitting unit LED1 emits light. When the determination result of step S820 is yes, it means that the light-emitting unit LED1 can emit light normally based on the conduction path P1. Since the premise of the first detection mode is that at least one light-emitting unit LED1~LED2 is known to be abnormal, the detection circuit 630 can infer that the light-emitting unit LED2 is abnormal. Thus, in step S831, when multiple light-emitting units LED1~LED2 in the conduction path P1 emit light, the detection circuit 630 determines that the abnormality of the pixel unit belongs to abnormality type B, that is, it determines that the light-emitting unit LED1 is normal and the light-emitting unit LED2 is abnormal. In step S832, the light-emitting unit LED2 that was determined to be abnormal is repaired.

[0092] On the other hand, if the judgment result of step S820 is negative, it means that the light-emitting unit LED1 cannot emit light normally based on the conduction path P1. The pixel detection circuit 600 continues with step S840.

[0093] In step S840, as Figure 7B As shown, switches 621-622 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 631 is turned off according to the detection signal AT. Transistor 632 is turned on according to the detection signal SEN. Thus, a conduction path P2 is formed through the light-emitting unit LED2. The conduction path P2 can be, for example, a second conduction path passing through transistor 632, the second reference terminal N2, the light-emitting unit LED2, the first reference terminal N1, the switching circuit (including multiple switches 621-622), and the second power supply terminal NS2.

[0094] In step S850, the detection circuit 630 determines whether the multiple light-emitting units LED1~LED2 are emitting light. Specifically, based on the conduction path P2, the detection circuit 630 determines whether the light-emitting unit LED1 is abnormal based on whether the light-emitting unit LED2 is emitting light. When the determination result of step S850 is yes, it means that the light-emitting unit LED2 can emit light normally based on the conduction path P2. It should be noted that the detection circuit 630 knows in step S820 that the light-emitting unit LED1 cannot emit light normally based on the conduction path P1. Thus, in step S861, when the multiple light-emitting units LED1~LED2 in the conduction path P1 are not emitting light, and when the multiple light-emitting units LED1~LED2 in the conduction path P2 are emitting light, the detection circuit 630 determines that the abnormality of the pixel unit belongs to abnormality type A, that is, it determines that the light-emitting unit LED1 is abnormal and the light-emitting unit LED2 is normal. In step S862, the light-emitting unit LED1 that is determined to be abnormal is repaired.

[0095] On the other hand, if the judgment result of step S850 is negative, it indicates that the light-emitting unit LED2 cannot emit light normally based on the conduction path P2. That is, in step S863, when multiple light-emitting units LED1~LED2 in conduction path P1 do not emit light, and when multiple light-emitting units LED1~LED2 in conduction path P2 also do not emit light, the detection circuit 630 determines that the abnormality of the pixel unit belongs to abnormality type C, that is, it determines that both light-emitting unit LED1 and light-emitting unit LED2 are abnormal. In step S864, the multiple light-emitting units LED1~LED2 that are determined to be abnormal are repaired.

[0096] Figures 9A to 9D Based on the present invention Figure 6 A schematic diagram illustrating the operation of the pixel detection circuit in the second detection mode, as shown in the embodiment. (Refer to...) Figures 9A to 9D In the second detection mode, the pixel detection circuit 600 detects whether each light-emitting unit LED1~LED2 in a single pixel unit is open-circuit or short-circuit abnormal, and illustrates the implementation details of step S232.

[0097] In the second detection mode, the voltage value of the first power supply voltage VDD has a first voltage value, a second voltage value, or a third voltage value. The voltage value of the second power supply voltage VSS also has a first voltage value, a second voltage value, or a third voltage value. The first voltage value is greater than the second voltage value and may be, for example, 10V. The second voltage value is greater than or equal to 0 and may be, for example, 0V. The third voltage value is less than 0 and may be, for example, -10V.

[0098] like Figure 9A as well as Figure 9B As shown, the pixel detection circuit 600 detects whether the light-emitting unit LED1 is open-circuit or short-circuit abnormal in the second detection mode. Switches 621-622 are turned off according to the first switch signal EM and the second switch signal DR, respectively. Transistor 631 is turned off according to the detection signal AT. Transistor 632 is turned on according to the detection signal SEN.

[0099] At this time, the first power supply voltage VDD has a first voltage value (e.g., Figure 9A (as shown in the 10V), or has a third voltage value (e.g., Figure 9B (as shown in the figure -10V). The second power supply voltage VSS is maintained with a second voltage value (e.g., 0V). Thus, the detection circuit 630 applies forward bias and reverse bias to the light-emitting unit LED1 based on the first power supply voltage VDD having a first voltage value (e.g., 10V) and a third voltage value (e.g., -10V), according to the multiple detection signals AT and SEN, respectively.

[0100] In detail, Figure 9AIn this circuit, since the switching circuit (including multiple switches 621-622) and transistor 631 are turned off and transistor 632 is turned on, the light-emitting unit LED1 is forward biased based on a first power supply voltage VDD having a first voltage value (e.g., 10V). At this time, assuming LED1 is functioning normally, LED1 is turned on and generates a current Id11. Current Id11 flows from the first power supply terminal NS1 through LED1, the second reference terminal N2, and transistor 632, and then to integrator 640, causing integrator 640 to generate a current change message. Since the current Id11 received by integrator 640 is greater than 0A, the current change message instructs LED1 to generate a current Id11 flowing to integrator 640 based on the forward bias.

[0101] On the other hand, assuming the light-emitting unit LED1 is in an open-circuit abnormality, LED1 will not be turned on and will not generate current Id11. Since the current Id11 received by integrator 640 is equal to 0A, the current change message indicates that LED1 does not generate current Id11 based on the forward bias voltage. Thus, the detection circuit 630 determines whether LED1 is in an open-circuit state and is therefore in an open-circuit abnormality based on the current change message generated by integrator 640 (including current Id11 greater than 0A or 0A).

[0102] exist Figure 9B In this configuration, since the switching circuit (i.e., multiple switches 621-622) and transistor 631 are turned off, and transistor 632 is turned on, the light-emitting unit LED1 is reverse-biased based on the first power supply voltage VDD having a third voltage value (e.g., -10V). At this time, assuming LED1 is functioning normally, LED1 will not be turned on and will not generate current Id12. Since the current Id12 received by integrator 640 is equal to 0A, the current change message indicates that LED1 does not generate current Id12 based on the reverse bias.

[0103] On the other hand, assuming the light-emitting unit LED1 is short-circuited, the two ends of LED1 (i.e., the first power supply voltage VS1 and the second reference terminal N2) are in a conducting state, causing current Id12 to be generated. Current Id12 flows out from integrator 640 and through transistor 632, the second reference terminal N2, and the first power supply voltage VS1. Since the current Id12 received by integrator 640 is less than 0A, the current change message instructs LED1 to generate current Id12 flowing out of integrator 640 based on reverse bias. Thus, detection circuit 630 determines whether LED1 is short-circuited and therefore short-circuited based on the current change message generated by integrator 640 (including current Id12 less than 0A or 0A).

[0104] like Figure 9C as well as Figure 9D As shown, the pixel detection circuit 600 detects whether the light-emitting unit LED2 is open-circuit or short-circuit abnormal in the second detection mode. Switches 621-622 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 631 is turned off according to the detection signal AT. Transistor 632 is turned on according to the detection signal SEN.

[0105] exist Figure 9C In this configuration, the first power supply voltage VDD has a third voltage value (e.g., -10V), and the second power supply voltage VSS also has a third voltage value (e.g., -10V). Since the switching circuit (including multiple switches 621-622) and transistor 632 are turned on, and transistor 631 is turned off, the light-emitting unit LED2 is forward biased based on the first power supply voltage VDD having a third voltage value (e.g., -10V) and the second power supply voltage VSS having a third voltage value (e.g., -10V).

[0106] At this time, assuming that the light-emitting unit LED2 is normal, LED2 is turned on and generates a current Id21. Current Id21 flows out of integrator 640 and through transistor 632, the second reference terminal N2, LED2, the first reference terminal N1, and the switching circuit (including multiple switches 621-622). Since the current Id21 received by integrator 640 is less than 0A, the current change message instructs LED2 to generate a current Id21 flowing out of integrator 640 based on a forward bias voltage.

[0107] On the other hand, assuming that the light-emitting unit LED2 is in an open-circuit abnormality, LED2 will not be turned on and will not generate current Id21. Since the current Id21 collected by the integrator 640 is equal to 0A, the current change message indicates that the light-emitting unit LED2 does not generate current Id21 based on the forward bias voltage. Thus, the detection circuit 630 determines whether the light-emitting unit LED2 is in an open-circuit state and is therefore in an open-circuit abnormality based on the current change message generated by the integrator 640 (including current Id21 less than 0A or 0A).

[0108] exist Figure 9DIn this configuration, the first power supply voltage VDD has a second voltage value (e.g., 0V), and the second power supply voltage VSS has a first voltage value (e.g., 10V). Since the switching circuit (including multiple switches 621-622) and transistor 632 are turned on, and transistor 631 is turned off, the light-emitting unit LED2 is reverse-biased based on the first power supply voltage VDD having a second voltage value (e.g., 0V) and the second power supply voltage VSS having a first voltage value (e.g., 10V).

[0109] At this point, assuming that the light-emitting unit LED2 is functioning normally, LED2 will not be turned on and will not generate current Id22. Since the current Id22 received by the integrator 640 is equal to 0A, the current change message indicates that LED2 does not generate current Id22 based on the reverse bias voltage.

[0110] On the other hand, assuming the light-emitting unit LED2 is short-circuited, the two ends of LED2 (i.e., the first reference terminal N1 and the second reference terminal N2) are in a conducting state, so that current Id22 is generated. Current Id22 flows from the second power supply terminal NS2 through the switching circuit (including multiple switches 621-622), the first reference terminal N1, LED2, the second reference terminal N2, and transistor 632, and flows to integrator 640, causing integrator 640 to generate a current change message. Since the current Id22 received by integrator 640 is greater than 0A, the current change message instructs LED2 to generate a current Id22 flowing to integrator 640 based on reverse bias. Thus, detection circuit 630 determines whether LED2 is short-circuited and therefore has a short-circuit fault based on the current change message generated by integrator 640 (including a current Id22 greater than 0A or 0A).

[0111] Figure 10 This is a circuit diagram of a pixel detection circuit according to a third embodiment of the present invention. (See reference) Figure 10 In the third embodiment, the pixel detection circuit 1000 includes a plurality of light-emitting units LED1~LED2, a switching circuit 1020, and a detection circuit 1030. The plurality of light-emitting units LED1~LED2 and the switching circuit 1020 can be referenced from... Figure 3 The relevant descriptions of the embodiments are explained and extrapolated.

[0112] exist Figure 10In this embodiment, the detection circuit 1030 includes a first transistor 1031 (hereinafter referred to as transistor 1031), a second transistor 1032 (hereinafter referred to as transistor 1032), and a third transistor 1033 (hereinafter referred to as transistor 1033). These transistors 1031-1033 may be implemented, for example, as PMOSFETs. The control terminal (i.e., gate) of transistor 1031 receives a first detection signal AT1 (hereinafter referred to as detection signal AT). The first terminal (e.g., source) of transistor 1031 is coupled to a second reference terminal N2. The second terminal (e.g., drain) of transistor 1031 is coupled to the first reference terminal N1. The control terminal (i.e., gate) of transistor 1032 receives one of a plurality of switching signals (e.g., a first switching signal EM) as a second detection signal EM (hereinafter referred to as detection signal EM). The first terminal (e.g., source) of transistor 1032 is coupled to the reference terminal N2. The second terminal (e.g., drain) of transistor 1032 is coupled to the first terminal (e.g., source) of transistor 1033. The control terminal (i.e., the gate) of transistor 1033 receives a third detection signal AT2 (hereinafter referred to as detection signal AT2). The second terminal (e.g., the drain) of transistor 1033 receives a data voltage Vdata.

[0113] Figures 11A to 11B Based on the present invention Figure 10 The illustrated embodiment shows the operation of the pixel detection circuit in the first detection mode. The pixel detection circuit 1000 can perform the following... Figure 8 The steps shown are for detecting whether each light-emitting unit LED1~LED2 in a single pixel unit is abnormal in the first detection mode, and the implementation details of step S231 are illustrated by example.

[0114] In the first detection mode, the first power supply voltage VDD has a first voltage value or a second voltage value. The second power supply voltage VSS has a second voltage value or a third voltage value. The first voltage value is greater than the second voltage value and may be, for example, 10V. The second voltage value is greater than or equal to 0 and may be, for example, 0V. The third voltage value is less than 0 and may be, for example, -10V.

[0115] like Figure 11AAs shown, multiple switches 1021-1022 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 1031 is turned on according to the detection signal AT1. Transistor 1032 is turned on according to the detection signal EM. Transistor 1033 is turned off according to the detection signal AT2. Thus, a conduction path P1 is formed through the light-emitting unit LED1. The conduction path P1 can be, for example, a first conduction path passing through the first power supply terminal NS1, the light-emitting unit LED1, the second reference terminal N2, transistor 1031, the first reference terminal N1, the switching circuit (including multiple switches 1021-1022), and the second power supply terminal NS2.

[0116] Based on the conduction path P1, the detection circuit 1030 determines whether the light-emitting unit LED2 is abnormal based on whether the light-emitting unit LED1 emits light. When multiple light-emitting units LED1~LED2 emit light based on the conduction path P1, it indicates that the light-emitting unit LED1 can emit light normally based on the conduction path P1. That is, when multiple light-emitting units LED1~LED2 emit light in the conduction path P1, the detection circuit 1030 determines that the abnormality of the pixel unit belongs to abnormality type B, that is, it determines that the light-emitting unit LED1 is normal and the light-emitting unit LED2 is abnormal.

[0117] On the other hand, when multiple light-emitting units LED1~LED2 do not emit light based on conduction path P1, it indicates that light-emitting unit LED1 cannot emit light normally based on conduction path P1. Next, as... Figure 11B As shown, multiple switches 1021-1022 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 1031 is turned off according to the detection signal AT1. Transistor 1032 is turned on according to the detection signal EM. Transistor 1033 is turned on according to the detection signal AT2. Thus, a conduction path P2 is formed through the light-emitting unit LED2. The conduction path P2 can be, for example, a second conduction path passing through multiple transistors 1032-1033, the second reference terminal N2, the light-emitting unit LED2, the first reference terminal N1, the switching circuit (including multiple switches 1021-1022), and the second power supply terminal NS2.

[0118] Based on the conduction path P2, the detection circuit 1030 determines whether the light-emitting unit LED1 is abnormal based on whether the light-emitting unit LED2 emits light. When multiple light-emitting units LED1~LED2 emit light based on the conduction path P2, it indicates that the light-emitting unit LED2 can emit light normally based on the conduction path P2. That is, when multiple light-emitting units LED1~LED2 in the conduction path P1 do not emit light, and when multiple light-emitting units LED1~LED2 in the conduction path P2 emit light, the detection circuit 1030 determines that the abnormality of the pixel unit belongs to abnormality type A, that is, it determines that the light-emitting unit LED1 is abnormal and the light-emitting unit LED2 is normal.

[0119] On the other hand, when multiple light-emitting units LED1~LED2 do not emit light based on conduction path P2, it indicates that light-emitting unit LED2 cannot emit light normally based on conduction path P2. That is, when multiple light-emitting units LED1~LED2 in conduction path P1 do not emit light, and when multiple light-emitting units LED1~LED2 in conduction path P2 also do not emit light, the detection circuit 1030 determines that the abnormality of the pixel unit belongs to abnormality type C, that is, it determines that light-emitting unit LED1 is abnormal and light-emitting unit LED2 is abnormal.

[0120] Figures 12A to 12D Based on the present invention Figure 10 A schematic diagram illustrating the operation of the pixel detection circuit in the second detection mode, as shown in the embodiment. (Refer to...) Figures 12A to 12D In the second detection mode, the pixel detection circuit 1000 detects whether each light-emitting unit LED1~LED2 in a single pixel unit is open-circuit or short-circuit abnormal, and illustrates the implementation details of step S232.

[0121] like Figure 12A as well as Figure 12B As shown, the pixel detection circuit 1000 detects whether the light-emitting unit LED1 is open-circuit or short-circuit abnormal in the second detection mode. Switch 1021 is turned on according to the first switch signal EM, and switch 1022 is turned off according to the second switch signal DR, so that the switching circuit (including multiple switches 1021~1022) is in the off state. Transistor 1031 is turned off according to the detection signal AT1. Transistor 1032 is turned on according to the detection signal EM. Transistor 1033 is turned on according to the detection signal AT2.

[0122] similar Figure 9A In the example, Figure 12AIn this configuration, the first power supply voltage VDD has a first voltage value (e.g., 10V), and the second power supply voltage VSS has a second voltage value (e.g., 0V). Since the switching circuit (including switch 1022) and transistor 1031 are turned off, and multiple transistors 1032-1033 are turned on, the light-emitting unit LED1 is forward biased based on the first power supply voltage VDD having the first voltage value (e.g., 10V).

[0123] At this time, assuming that the light-emitting unit LED1 is normal, LED1 is turned on and generates a current Id11. The current Id11 flows from the first power supply terminal NS1 through the light-emitting unit LED1 and to the integrator 1040, causing the integrator 1040 to generate a current change message. Since the current Id11 received by the integrator 1040 is greater than 0A, the current change message instructs the light-emitting unit LED1 to generate a current Id11 flowing to the integrator 1040 based on the forward bias voltage.

[0124] On the other hand, assuming the light-emitting unit LED1 is in an open-circuit abnormality, LED1 will not be turned on and will not generate current Id11. Since the current Id11 received by integrator 1040 is equal to 0A, the current change message indicates that LED1 does not generate current Id11 based on the forward bias. Thus, the detection circuit 1030 determines whether LED1 is in an open-circuit state and is therefore in an open-circuit abnormality based on the current change message generated by integrator 1040 (including current Id11 greater than 0A or 0A).

[0125] similar Figure 9B In the example, Figure 12B In this configuration, because the switching circuit (including switch 1022) and transistor 1031 are turned off, and multiple transistors 1032-1033 are turned on, the light-emitting unit LED1 is reverse-biased based on the first power supply voltage VDD having a third voltage value (e.g., -10V). At this time, assuming LED1 is functioning normally, LED1 will not be turned on and will not generate current Id12. Since the current Id12 received by integrator 1040 is equal to 0A, the current change message indicates that LED1 does not generate current Id12 based on the reverse bias.

[0126] On the other hand, assuming the light-emitting unit LED1 is short-circuited, the two ends of LED1 (i.e., the first power supply voltage VS1 and the second reference terminal N2) are in a conducting state, causing current Id12 to be generated. Current Id12 flows out from integrator 1040 and through multiple transistors 1032-1033, the second reference terminal N2, and the first power supply voltage VS1. Since the current Id12 received by integrator 1040 is less than 0A, the current change message instructs LED1 to generate a current Id12 flowing out of integrator 1040 based on reverse bias. Thus, detection circuit 1030 determines whether LED1 is short-circuited and abnormal based on the current change message generated by integrator 1040 (including a current Id12 less than 0A or 0A).

[0127] like Figure 12C as well as Figure 12D As shown, the pixel detection circuit 1000 detects whether the light-emitting unit LED2 is open-circuit or short-circuit abnormal in the second detection mode. Multiple switches 1021-1022 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 1031 is turned off according to the detection signal AT1. Transistor 1032 is turned on according to the detection signal EM. Transistor 1033 is turned on according to the detection signal AT2.

[0128] similar Figure 9C In the example, Figure 12C In this configuration, the first power supply voltage VDD has a third voltage value (e.g., -10V), and the second power supply voltage VSS also has a third voltage value (e.g., -10V). Since the switching circuit (including multiple switches 1021-1022) and multiple transistors 1032-1033 are turned on, and transistor 1031 is turned off, the light-emitting unit LED2 is forward biased based on the first power supply voltage VDD having a third voltage value (e.g., -10V) and the second power supply voltage VSS having a third voltage value (e.g., -10V).

[0129] At this time, assuming that the light-emitting unit LED2 is normal, LED2 is turned on and generates a current Id21. Current Id21 flows out of integrator 1040 and through multiple transistors 1032-1033, the second reference terminal N2, LED2, the first reference terminal N1, and the switching circuit (including multiple switches 1021-1022). Since the current Id21 received by integrator 1040 is less than 0A, the current change message instructs LED2 to generate a current Id21 flowing out of integrator 1040 based on a forward bias voltage.

[0130] On the other hand, assuming that the light-emitting unit LED2 is in an open-circuit abnormality, LED2 will not be turned on and will not generate current Id21. Since the current Id21 received by the integrator 1040 is equal to 0A, the current change message indicates that the light-emitting unit LED2 does not generate current Id21 based on the forward bias voltage. Thus, the detection circuit 1030 determines whether the light-emitting unit LED2 is in an open-circuit state and is therefore in an open-circuit abnormality based on the current change message generated by the integrator 1040 (including current Id21 greater than 0A or 0A).

[0131] similar Figure 9D In the example, Figure 12D In this configuration, the first power supply voltage VDD has a second voltage value (e.g., 0V), and the second power supply voltage VSS has a first voltage value (e.g., 10V). Since the switching circuit (including multiple switches 1021-1022) and multiple transistors 1032-1033 are turned on, and the first transistor 1031 is turned off, the light-emitting unit LED2 is reverse-biased based on the first power supply voltage VDD having a second voltage value (e.g., 0V) and the second power supply voltage VSS having a first voltage value (e.g., 10V).

[0132] At this point, assuming that the light-emitting unit LED2 is functioning normally, LED2 will not be turned on and will not generate current Id22. Since the current Id22 received by the integrator 1040 is equal to 0A, the current change message indicates that LED2 does not generate current Id22 based on the reverse bias voltage.

[0133] On the other hand, assuming the light-emitting unit LED2 is short-circuited, both ends of LED2 (i.e., the first reference terminal N1 and the second reference terminal N2) are in a conducting state, causing current Id22 to be generated. Current Id22 flows from the second power supply terminal NS2 through the switching circuit (including multiple switches 1021-1022), the first reference terminal N1, LED2, the second reference terminal N2, and multiple transistors 1032-1033, and then to the integrator 1040, causing the integrator 1040 to generate a current change message. Since the current Id22 received by the integrator 1040 is greater than 0A, the current change message instructs LED2 to generate a current Id22 flowing to the integrator 1040 based on a reverse bias. Thus, the detection circuit 1030 determines whether LED2 is short-circuited and therefore has a short-circuit fault based on the current change message generated by the integrator 1040 (including a current Id22 greater than 0A or 0A).

[0134] Figure 13 This is a circuit diagram of a pixel detection circuit according to a fourth embodiment of the present invention. (See reference) Figure 13In the fourth embodiment, the pixel detection circuit 1300 includes a plurality of light-emitting units LED1~LED2, a switching circuit 1320, and a detection circuit 1330. The plurality of light-emitting units LED1~LED2 and the switching circuit 1320 can be found in [reference needed]. Figure 3 Implementation examples or Figure 10 The relevant descriptions of the embodiments are explained and extrapolated.

[0135] exist Figure 13 In this embodiment, the detection circuit 1330 includes a first transistor 1331 (hereinafter referred to as transistor 1331), a second transistor 1332 (hereinafter referred to as transistor 1332), and a third transistor 1333 (hereinafter referred to as transistor 1333). These transistors 1331-1333 may be implemented, for example, as PMOSFETs. The control terminal (i.e., gate) of transistor 1331 receives a first detection signal AT1 (hereinafter referred to as detection signal AT1). The first terminal (e.g., drain) of transistor 1331 is coupled to a first reference terminal N1. The control terminal (i.e., gate) of transistor 1332 receives a second detection signal AT2 (hereinafter referred to as detection signal AT2). The first terminal (e.g., source) of transistor 1332 is coupled to a second reference terminal N2. The second terminal (e.g., drain) of transistor 1332 is coupled to the second terminal (e.g., source) of the first transistor 1331 and the first terminal (e.g., source) of transistor 1333. The gate of transistor 1333 receives one of a plurality of switching signals (e.g., a first switching signal EM) as a third detection signal EM (hereinafter referred to as the detection signal EM). The second terminal (e.g., the drain) of transistor 1333 receives a data voltage Vdata.

[0136] Figures 14A to 14B Based on the present invention Figure 13 The illustrated embodiment shows the operation of the pixel detection circuit in the first detection mode. The pixel detection circuit 1300 can perform the following... Figure 8 The steps shown are for detecting whether each light-emitting unit LED1~LED2 in a single pixel unit is abnormal in the first detection mode, and the implementation details of step S231 are illustrated by example.

[0137] In the first detection mode, the first power supply voltage VDD has a first voltage value or a second voltage value. The second power supply voltage VSS maintains a second voltage value. The first voltage value is greater than the second voltage value, and may be, for example, 10V. The second voltage value is greater than or equal to 0, and may be, for example, 0V.

[0138] like Figure 14AAs shown, multiple switches 1321-1322 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 1331 is turned on according to the detection signal AT1. Transistor 1332 is turned on according to the detection signal AT2. Transistor 1333 is turned on according to the detection signal EM. Thus, a conduction path P1 is formed through the light-emitting unit LED1. The conduction path P1 can be, for example, a first conduction path passing through the first power supply terminal NS1, the light-emitting unit LED1, the second reference terminal N2, the multiple transistors 1331-1333, the switching circuit (including the multiple switches 1321-1322), and the second power supply terminal NS2.

[0139] Based on the conduction path P1, the detection circuit 1330 determines whether the light-emitting unit LED2 is abnormal based on whether the light-emitting unit LED1 emits light. When multiple light-emitting units LED1~LED2 emit light based on the conduction path P1, it indicates that the light-emitting unit LED1 can emit light normally based on the conduction path P1. That is, when multiple light-emitting units LED1~LED2 emit light in the conduction path P1, the detection circuit 1330 determines that the abnormality of the pixel unit belongs to abnormality type B, that is, it determines that the light-emitting unit LED1 is normal and the light-emitting unit LED2 is abnormal.

[0140] On the other hand, when multiple light-emitting units LED1~LED2 do not emit light based on conduction path P1, it indicates that light-emitting unit LED1 cannot emit light normally based on conduction path P1. Next, as... Figure 14B As shown, multiple switches 1321-1322 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 1331 is turned off according to the detection signal AT1. Transistor 1332 is turned on according to the detection signal AT2. Transistor 1333 is turned on according to the detection signal EM. Thus, a conduction path P2 is formed through the light-emitting unit LED2. The conduction path P2 can be, for example, a second conduction path passing through multiple transistors 1332-1333, the second reference terminal N2, the light-emitting unit LED2, the first reference terminal N1, the switching circuit (including multiple switches 1321-1322), and the second power supply terminal NS2.

[0141] Based on the conduction path P2, the detection circuit 1330 determines whether the light-emitting unit LED1 is abnormal based on whether the light-emitting unit LED2 emits light. When multiple light-emitting units LED1~LED2 emit light based on the conduction path P2, it indicates that the light-emitting unit LED2 can emit light normally based on the conduction path P2. That is, when multiple light-emitting units LED1~LED2 in the conduction path P1 do not emit light, and when multiple light-emitting units LED1~LED2 in the conduction path P2 emit light, the detection circuit 1330 determines that the abnormality of the pixel unit belongs to abnormality type A, that is, it determines that the light-emitting unit LED1 is abnormal and the light-emitting unit LED2 is normal.

[0142] On the other hand, when multiple light-emitting units LED1~LED2 do not emit light based on conduction path P2, it indicates that light-emitting unit LED2 cannot emit light normally based on conduction path P2. That is, when multiple light-emitting units LED1~LED2 in conduction path P1 do not emit light, and when multiple light-emitting units LED1~LED2 in conduction path P2 also do not emit light, the detection circuit 1330 determines that the abnormality of the pixel unit belongs to abnormality type C, that is, it determines that light-emitting unit LED1 is abnormal and light-emitting unit LED2 is abnormal.

[0143] Figures 15A to 15D Based on the present invention Figure 13 A schematic diagram illustrating the operation of the pixel detection circuit in the second detection mode, as shown in the embodiment. (Refer to...) Figures 15A to 15D In the second detection mode, the pixel detection circuit 1300 detects whether each light-emitting unit LED1~LED2 in a single pixel unit is open-circuit or short-circuit abnormal, and illustrates the implementation details of step S232.

[0144] like Figure 15A as well as Figure 15B As shown, the pixel detection circuit 1300 detects whether the light-emitting unit LED1 is open-circuit or short-circuit abnormal in the second detection mode. Switch 1321 is turned on according to the first switch signal EM, and switch 1322 is turned off according to the second switch signal DR, so that the switching circuit (including multiple switches 1321~1322) is in the off state. Transistor 1331 is turned off according to the detection signal AT1. Transistor 1332 is turned on according to the detection signal AT2. Transistor 1333 is turned on according to the detection signal EM.

[0145] similar Figure 12A In the example, Figure 15AIn this configuration, the first power supply voltage VDD has a first voltage value (e.g., 10V), and the second power supply voltage VSS has a second voltage value (e.g., 0V). Since the switching circuit (including switch 1322) and transistor 1031 are turned off, and multiple transistors 1332-1333 are turned on, the light-emitting unit LED1 is forward biased based on the first power supply voltage VDD having the first voltage value (e.g., 10V).

[0146] At this time, assuming that the light-emitting unit LED1 is normal, LED1 is turned on and generates a current Id11. The current Id11 flows from the first power supply terminal NS1 through the light-emitting unit LED1 and to the integrator 1340, causing the integrator 1340 to generate a current change message. Since the current Id11 received by the integrator 1340 is greater than 0A, the current change message instructs the light-emitting unit LED1 to generate a current Id11 flowing to the integrator 1340 based on the forward bias voltage.

[0147] On the other hand, assuming that the light-emitting unit LED1 is in an open-circuit abnormality, LED1 will not be turned on and will not generate current Id11. Since the current Id11 received by the integrator 1340 is equal to 0A, the current change message indicates that LED1 does not generate current Id11 based on the forward bias voltage. Thus, the detection circuit 1330 determines whether LED1 is in an open-circuit state and is abnormal based on the current change message generated by the integrator 1340 (including current Id11 greater than 0A or 0A).

[0148] similar Figure 12B In the example, Figure 15B In this configuration, because the switching circuit (including switch 1322) and transistor 1331 are turned off, and multiple transistors 1332-1333 are turned on, the light-emitting unit LED1 is reverse-biased based on the first power supply voltage VDD having a third voltage value (e.g., -10V). At this time, assuming LED1 is functioning normally, LED1 will not be turned on and will not generate current Id12. Since the current Id12 received by integrator 1340 is equal to 0A, the current change message indicates that LED1 does not generate current Id12 based on the reverse bias.

[0149] On the other hand, assuming the light-emitting unit LED1 is short-circuited, the two ends of LED1 (i.e., the first power supply voltage VS1 and the second reference terminal N2) are in a conducting state, causing current Id12 to be generated. Current Id12 flows out from integrator 1040 and through multiple transistors 1332-1333, the second reference terminal N2, and the first power supply voltage VS1. Since the current Id12 received by integrator 1040 is less than 0A, the current change information instructs LED1 to generate current Id12 flowing out of integrator 1340 based on reverse bias. Thus, detection circuit 1030 determines whether LED1 is short-circuited and abnormal based on the current change information generated by integrator 1340 (including current Id12 less than 0A or 0A).

[0150] like Figure 15C as well as Figure 15D As shown, the pixel detection circuit 1300 detects whether the light-emitting unit LED2 is open-circuit or short-circuit abnormal in the second detection mode. Multiple switches 1321-1322 are turned on according to the first switch signal EM and the second switch signal DR, respectively. Transistor 1331 is turned off according to the detection signal AT1. Transistor 1332 is turned on according to the detection signal EM. Transistor 1333 is turned on according to the detection signal AT2.

[0151] similar Figure 12C In the example, Figure 15C In this configuration, the first power supply voltage VDD has a third voltage value (e.g., -10V), and the second power supply voltage VSS also has a third voltage value (e.g., -10V). Since the switching circuit (including multiple switches 1321-1322) and multiple transistors 1332-1333 are turned on, and transistor 1331 is turned off, the light-emitting unit LED2 is forward biased based on the first power supply voltage VDD having a third voltage value (e.g., -10V) and the second power supply voltage VSS having a third voltage value (e.g., -10V).

[0152] At this time, assuming that the light-emitting unit LED2 is normal, LED2 is turned on and generates a current Id21. Current Id21 flows out of integrator 1340 and through multiple transistors 1332-1333, the second reference terminal N2, LED2, the first reference terminal N1, and the switching circuit (including multiple switches 1321-1322). Since the current Id21 received by integrator 1340 is less than 0A, the current change signal instructs LED2 to generate a current Id21 flowing out of integrator 1340 based on a forward bias.

[0153] On the other hand, assuming that the light-emitting unit LED2 is in an open-circuit abnormality, LED2 will not be turned on and will not generate current Id21. Since the current Id21 received by the integrator 1340 is equal to 0A, the current change message indicates that the light-emitting unit LED2 does not generate current Id21 based on the forward bias voltage. Thus, the detection circuit 1330 determines whether the light-emitting unit LED2 is in an open-circuit state and is therefore in an open-circuit abnormality based on the current change message generated by the integrator 1340 (including current Id21 greater than 0A or 0A).

[0154] similar Figure 12D In the example, Figure 15D In this configuration, the first power supply voltage VDD has a second voltage value (e.g., 0V), and the second power supply voltage VSS has a first voltage value (e.g., 10V). Since the switching circuit (including multiple switches 1321-1322) and multiple transistors 1332-1333 are turned on, and transistor 1331 is turned off, the light-emitting unit LED2 is reverse-biased based on the first power supply voltage VDD having a second voltage value (e.g., 0V) and the second power supply voltage VSS having a first voltage value (e.g., 10V).

[0155] At this point, assuming that the light-emitting unit LED2 is normal, LED2 will not be turned on and will not generate current Id22. Since the current Id22 received by the integrator 1340 is equal to 0A, the current change message indicates that LED2 does not generate current Id22 based on the reverse bias voltage.

[0156] On the other hand, assuming the light-emitting unit LED2 is short-circuited, both ends of LED2 (i.e., the first reference terminal N1 and the second reference terminal N2) are in a conducting state, causing current Id22 to be generated. Current Id22 flows from the second power supply terminal NS2 through the switching circuit (including multiple switches 1321-1322), the first reference terminal N1, LED2, the second reference terminal N2, and multiple transistors 1332-1333, and then to the integrator 1340, causing the integrator 1340 to generate a current change message. Since the current Id22 received by the integrator 1340 is greater than 0A, the current change message instructs LED2 to generate a current Id22 flowing to the integrator 1340 based on a reverse bias. Thus, the detection circuit 1330 determines whether LED2 is short-circuited and therefore has a short-circuit fault based on the current change message generated by the integrator 1340 (including a current Id22 greater than 0A or 0A).

[0157] In summary, the pixel detection circuit and its applicable detection method according to embodiments of the present invention can detect whether each of a plurality of series-connected light-emitting units is abnormal. By bridging the plurality of light-emitting units, the pixel detection circuit can detect the abnormal state of each light-emitting unit one by one. In various detection modes, based on the multiple conduction paths flowing through each light-emitting unit, or based on the current change information of each light-emitting unit being subjected to forward and reverse bias voltages, the pixel detection circuit can effectively determine whether each light-emitting unit is abnormal.

[0158] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A pixel detection circuit, characterized in that, include: Multiple light-emitting units are connected in series between a first power supply terminal and a first reference terminal; A switching circuit, coupled between the first reference terminal and a second power supply terminal, is used to receive multiple switching signals; as well as A detection circuit, coupled to the first reference terminal and a second reference terminal between the light-emitting units, is used to receive multiple detection signals and operates in a first detection mode or a second detection mode. In this first detection mode, the switching circuit is turned on, and the detection circuit sequentially forms multiple conduction paths flowing through each of the light-emitting units based on the detection signals, so as to determine whether each light-emitting unit is abnormal based on whether the light-emitting units emit light in these conduction paths. In the second detection mode, the switching circuit and the detection circuit, based on a first power supply voltage at the first power supply terminal and a second power supply voltage at the second power supply terminal, sequentially apply a forward bias voltage and a reverse bias voltage to each of the light-emitting units according to the switching signals and the detection signals to form a current change message flowing to an integrator coupled to the detection circuit, and the detection circuit determines whether each of the light-emitting units is abnormal based on the current change message.

2. The pixel detection circuit as described in claim 1, characterized in that, When any of the light-emitting units is known to be abnormal, the pixel detection circuit selects to operate in the first detection mode.

3. The pixel detection circuit as described in claim 1, characterized in that, In the first detection mode, the conduction paths include a first conduction path flowing through the first power supply terminal, a first light-emitting unit among the light-emitting units, the first reference terminal, the switching circuit, and the second power supply terminal.

4. The pixel detection circuit as described in claim 3, characterized in that, In the first detection mode, the conduction paths also include a second conduction path that flows through the second reference terminal, a second light-emitting unit among the light-emitting units, the first reference terminal, the switching circuit, and the second power supply terminal.

5. The pixel detection circuit as described in claim 4, characterized in that, When the light-emitting units in the first conduction path emit light, the detection circuit determines that the first light-emitting unit is normal and the second light-emitting unit is abnormal. When the light-emitting units in the first conduction path are not emitting light, and when the light-emitting units in the second conduction path are emitting light, the detection circuit determines that the first light-emitting unit is abnormal and the second light-emitting unit is normal. When the light-emitting units in the first conduction path do not emit light, and when the light-emitting units in the second conduction path do not emit light, the detection circuit determines that the first light-emitting unit is abnormal and the second light-emitting unit is abnormal.

6. The pixel detection circuit as described in claim 5, characterized in that, In the first detection mode, the first power supply voltage has a first voltage value or a second voltage value, and the second power supply voltage has a second voltage value or a third voltage value, wherein the first voltage value is greater than the second voltage value, the second voltage value is greater than or equal to 0, and the third voltage value is less than 0.

7. The pixel detection circuit as described in claim 1, characterized in that, In the second detection mode, the switching circuit is turned off, and the detection circuit applies the forward bias and the reverse bias to a first light-emitting unit among the light-emitting units based on the first power supply voltage having a first voltage value and a third voltage value, respectively, according to the detection signals, so that the detection circuit determines whether the first light-emitting unit is in an open circuit state or a short circuit state and is therefore abnormal based on the current change information.

8. The pixel detection circuit as described in claim 7, characterized in that, In the second detection mode, the switching circuit is turned on, so that the detection circuit applies a forward bias voltage to a second light-emitting unit based on the first power supply voltage having the third voltage value and the second power supply voltage having the third voltage value, according to the detection signals. The detection circuit then determines whether the second light-emitting unit is in an open-circuit state, indicating an abnormality, based on the current change information. In the second detection mode, the switching circuit is turned on so that the detection circuit applies the reverse bias voltage to the second light-emitting unit based on the first power supply voltage having a second power supply voltage value and the second power supply voltage having the first power supply voltage value, and the detection circuit determines whether the second light-emitting unit is in a short circuit state and is abnormal based on the current change information.

9. The pixel detection circuit as described in claim 8, characterized in that, In the second detection mode, the first voltage value is greater than the second voltage value, the second voltage value is greater than or equal to 0, and the third voltage value is less than 0.

10. The pixel detection circuit as described in claim 1, characterized in that, These light-emitting units include: A first light-emitting unit, having an anode terminal coupled to the first power supply terminal, and a cathode terminal coupled to the second reference terminal; and A second light-emitting unit has a positive terminal coupled to the second reference terminal, and a negative terminal coupled to the first reference terminal.

11. The pixel detection circuit as described in claim 10, characterized in that, The detection circuit includes: A first transistor having a control terminal for receiving a first detection signal, a first terminal of the first transistor coupled to the second reference terminal, and a second terminal of the first transistor coupled to the first reference terminal; and A second transistor has a control terminal that receives a second detection signal, a first terminal of the second transistor that is coupled to the first reference terminal, and a second terminal of the second transistor that receives a data voltage.

12. The pixel detection circuit as described in claim 11, characterized in that, In the first detection mode, the first transistor is turned on according to the first detection signal, and the second transistor is turned off according to the second detection signal, so that the detection circuit can determine whether the first light-emitting unit and the second light-emitting unit are abnormal based on whether the first light-emitting unit and the second light-emitting unit emit light or not.

13. The pixel detection circuit as described in claim 10, characterized in that, The detection circuit includes: A first transistor having a control terminal for receiving a first detection signal, a first terminal of the first transistor coupled to the second reference terminal, and a second terminal of the first transistor coupled to the first reference terminal; and A second transistor has a control terminal that receives a second detection signal, a first terminal of the second transistor that is coupled to the second reference terminal, and a second terminal of the second transistor that receives a data voltage.

14. The pixel detection circuit as described in claim 13, characterized in that, In this first detection mode, the first transistor is turned on according to the first detection signal, and the second transistor is turned off according to the second detection signal, so that the detection circuit determines whether the second light-emitting unit is abnormal based on whether the first light-emitting unit emits light or not. Next, the first transistor is turned off according to the first detection signal, and the second transistor is turned on according to the second detection signal, so that the detection circuit can determine whether the first light-emitting unit is abnormal based on whether the second light-emitting unit emits light or not.

15. The pixel detection circuit as described in claim 13, characterized in that, In this second detection mode, the switching circuit is turned off, the first transistor is turned off according to the first detection signal, and the second transistor is turned on according to the second detection signal, so that the first light-emitting unit is subjected to the forward bias voltage or the reverse bias voltage based on the first power supply voltage, and the detection circuit determines whether the first light-emitting unit is in an open circuit state or a short circuit state and thus an abnormality based on the current change information. In the second detection mode, the switching circuit is turned on, the first transistor is turned off according to the first detection signal, and the second transistor is turned on according to the second detection signal, so that the second light-emitting unit is subjected to the forward bias voltage or the reverse bias voltage based on the first power supply voltage and the second power supply voltage, and the detection circuit determines whether the second light-emitting unit is in an open circuit state or a short circuit state and is therefore abnormal based on the current change information.

16. The pixel detection circuit as described in claim 10, characterized in that, The detection circuit includes: A first transistor has a control terminal for receiving a first detection signal, a first terminal of the first transistor being coupled to the second reference terminal, and a second terminal of the first transistor being coupled to the first reference terminal. A second transistor having a control terminal that receives one of the switching signals as a second detection signal, and a first terminal of the second transistor coupled to the second reference terminal; and A third transistor has a control terminal that receives a third detection signal, a first terminal of the third transistor that is coupled to a second terminal of the second transistor, and a second terminal of the third transistor that receives a data voltage.

17. The pixel detection circuit as described in claim 16, characterized in that, In this first detection mode, the first transistor is turned on according to the first detection signal, the second transistor is turned on according to the second detection signal, and the third transistor is turned off according to the third detection signal, so that the detection circuit can determine whether the second light-emitting unit is abnormal based on whether the first light-emitting unit emits light or not. Next, the first transistor is turned off according to the first detection signal, the second transistor is turned on according to the second detection signal, and the third transistor is turned on according to the third detection signal, so that the detection circuit can determine whether the first light-emitting unit is abnormal based on whether the second light-emitting unit emits light or not.

18. The pixel detection circuit as described in claim 16, characterized in that, In this second detection mode, the switching circuit is turned off, the first transistor is turned off according to the first detection signal, the second transistor is turned on according to the second detection signal, and the third transistor is turned on according to the third detection signal. This allows the first light-emitting unit to be subjected to either a forward bias or a reverse bias based on the first power supply voltage. The detection circuit then determines whether the first light-emitting unit is in an open-circuit or short-circuit state based on the current change information, thus identifying an anomaly. In the second detection mode, the switching circuit is turned on, the first transistor is turned off according to the first detection signal, the second transistor is turned on according to the second detection signal, and the third transistor is turned on according to the third detection signal, so that the second light-emitting unit is subjected to the forward bias voltage or the reverse bias voltage based on the first power supply voltage and the second power supply voltage, and the detection circuit determines whether the second light-emitting unit is in an open circuit state or a short circuit state and is therefore abnormal based on the current change information.

19. The pixel detection circuit as described in claim 10, characterized in that, The detection circuit includes: A first transistor having a control terminal for receiving a first detection signal, the first terminal of the first transistor being coupled to the first reference terminal; A second transistor having a control terminal for receiving a second detection signal, and a first terminal of the second transistor coupled to the second reference terminal; and A third transistor has a control terminal that receives one of the switching signals as a third detection signal, a first terminal of the third transistor being coupled to a second terminal of the first transistor and a second terminal of the second transistor, and the second terminal of the third transistor receiving a data voltage.

20. The pixel detection circuit as described in claim 19, characterized in that, In this first detection mode, the first transistor is turned on according to the first detection signal, the second transistor is turned on according to the second detection signal, and the third transistor is turned on according to the third detection signal, so that the detection circuit can determine whether the second light-emitting unit is abnormal based on whether the first light-emitting unit emits light or not. Next, the first transistor is turned off according to the first detection signal, the second transistor is turned on according to the second detection signal, and the third transistor is turned on according to the third detection signal, so that the detection circuit can determine whether the first light-emitting unit is abnormal based on whether the second light-emitting unit emits light or not.

21. The pixel detection circuit as described in claim 19, characterized in that, In this second detection mode, the switching circuit is turned off, the first transistor is turned off according to the first detection signal, the second transistor is turned on according to the second detection signal, and the third transistor is turned on according to the third detection signal. This allows the first light-emitting unit to be subjected to either a forward bias or a reverse bias based on the first power supply voltage. The detection circuit then determines whether the first light-emitting unit is in an open-circuit or short-circuit state based on the current change information, thus identifying an anomaly. In the second detection mode, the switching circuit is turned on, the first transistor is turned off according to the first detection signal, the second transistor is turned on according to the second detection signal, and the third transistor is turned on according to the third detection signal. The second light-emitting unit is subjected to the forward bias or the reverse bias based on the first power supply voltage and the second power supply voltage. The detection circuit determines whether the second light-emitting unit is in an open circuit state or a short circuit state and is therefore abnormal based on the current change information.

22. The pixel detection circuit as described in claim 10, characterized in that, The switching circuit includes: A first switch, having a control terminal receiving a first switch signal, the first terminal of the first switch being coupled to the first reference terminal; and A second switch having a control terminal that receives a second switch signal, the first terminal of the second switch being coupled to the second terminal of the first transistor, and the second terminal of the second switch being coupled to the second power supply terminal.

23. A detection method applicable to a one-pixel detection circuit, characterized in that, include: A detection circuit receives multiple detection signals and operates in a first detection mode or a second detection mode, wherein the detection circuit is coupled to a first reference terminal and a second reference terminal between multiple light-emitting units, and the light-emitting units are connected in series between a first power supply terminal and the first reference terminal. Multiple switching signals are received through a switching circuit, wherein the switching circuit is coupled between the first reference terminal and a second power supply terminal. In this first detection mode, the switching circuit is turned on, and the detection circuit sequentially forms multiple conduction paths flowing through each of the light-emitting units based on the detection signals, so as to determine whether each light-emitting unit is abnormal based on whether the light-emitting units emit light in these conduction paths; and In the second detection mode, the switching circuit and the detection circuit, based on a first power supply voltage at the first power supply terminal and a second power supply voltage at the second power supply terminal, sequentially apply a forward bias voltage and a reverse bias voltage to each of the light-emitting units according to the switching signals and the detection signals to form a current change message flowing to an integrator coupled to the detection circuit, and the detection circuit determines whether each of the light-emitting units is abnormal based on the current change message.

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