Voltage detection display circuit and driving method thereof, display panel and display device

Abstract

The application discloses a voltage detection display circuit and a driving method thereof, a display panel and a display device, and relates to the technical field of display. In the circuit, an impedance measurement module is configured to determine the voltage wire impedance of a pixel structure module according to a preset voltage detection signal and a pixel power voltage when a display driving module provides the pixel power voltage to the pixel structure module through a voltage wire path from a power supply end to a power supply access point, and transmit the voltage wire impedance to a sensing wire; the display driving module is configured to acquire the voltage wire impedance transmitted by the impedance measurement module through the sensing wire, and determine a compensation voltage according to the normal display current of the pixel structure module and the voltage wire impedance; and the compensation voltage is superimposed on the pixel power voltage and then connected to the power supply access point for normal display of the pixel structure module. The application aims to solve the display problem of uneven brightness caused by metal wire resistance to improve the display quality.

Description

Voltage detection and display circuit and its driving method, display panel and display device Technical Field

[0001] This application relates to the field of display technology, and in particular to a voltage detection display circuit and its driving method, a display panel, and a display device. Background Technology

[0002] With the continuous development of display technology, OLED (Organic Light-Emitting Diode) products are widely used in mobile phones, automobiles, central control systems, smart homes, smart offices, watches, smart bracelets, and many other fields. Users are also placing higher demands on the display quality of OLED products.

[0003] ELVDD is one of the key voltages driving OLED pixels to emit light. It is generated by the DDIC (Display Driver IC) and transmitted to each pixel position on the panel. However, during transmission, due to the resistance of the metal traces, a voltage drop occurs when current flows, known as the IR Drop phenomenon. As the signal transmission distance increases, the voltage drop gradually accumulates, causing the ELVDD voltage received at the far end of the panel to be lower than that at the near end. This leads to uneven brightness and seriously affects the display quality of OLED products.

[0004] Therefore, improving the display quality of OLED products is a pressing technical problem that needs to be solved. Summary of the Invention

[0005] The main objective of this application is to provide a voltage detection display circuit and its driving method, a display panel, and a display device, which aim to improve the uniformity of brightness display in OLED products.

[0006] To achieve the above objectives, this application provides a voltage detection and display circuit, which includes a display driving module, an array-distributed pixel structure module, and an impedance measurement module and sensing traces electrically connected to the pixel structure module.

[0007] The power supply access point of the pixel structure module is electrically connected to the power supply terminal of the display driver module and the signal access terminal of the impedance measurement module, respectively. The signal output terminal of the impedance measurement module is electrically connected to the impedance detection terminal of the display driver module through the sensing trace.

[0008] The impedance measurement module is configured to determine the voltage trace impedance of the pixel structure module based on a preset voltage detection signal and the pixel power supply voltage when the display driving module provides pixel power voltage to the pixel structure module through the voltage trace from the power supply terminal to the power supply access point, and transmit the voltage trace impedance to the sensing trace.

[0009] The display driving module is configured to acquire the voltage trace impedance sent by the impedance measurement module via the sensing trace, determine a compensation voltage based on the normal display current of the pixel structure module and the voltage trace impedance, and then connect the compensation voltage to the pixel power supply voltage and the power supply access point so that the pixel structure module can display normally.

[0010] In one embodiment, the impedance measurement module includes a first thin-film transistor and a voltage detection signal terminal;

[0011] The gate of the first thin-film transistor is electrically connected to the voltage detection signal terminal;

[0012] The first path terminal of the first thin-film transistor constitutes the signal access terminal of the impedance measurement module and is electrically connected to the power supply access terminal of the pixel structure module.

[0013] The second terminal of the first thin-film transistor constitutes the signal output terminal of the impedance measurement module and is electrically connected to the sensing trace.

[0014] In one embodiment, the display driving module includes a detection switching unit, an impedance detection unit, a sensing unit, and a timing control unit;

[0015] The sensing terminal of the detection switching unit is electrically connected to the sensing unit, the detection terminal of the detection switching unit is electrically connected to the impedance detection unit, and the control terminal of the detection switching unit is electrically connected to the timing control unit.

[0016] The signal acquisition terminal of the detection switching unit constitutes the impedance detection terminal of the display driving module and is electrically connected to the sensing trace.

[0017] In one embodiment, the detection switching unit includes an N-type MOS transistor and a P-type MOS transistor;

[0018] The gate of the N-type MOS transistor is electrically connected to the gate of the P-type MOS transistor. The connection node between the gate of the N-type MOS transistor and the gate of the P-type MOS transistor forms the control terminal of the detection switching unit and is electrically connected to the timing control unit.

[0019] The first path terminal of the N-type MOS transistor constitutes the sensing terminal of the detection switching unit and is electrically connected to the sensing unit; the first path terminal of the P-type MOS transistor constitutes the detection terminal of the detection switching unit and is electrically connected to the impedance detection unit.

[0020] The second path terminal of the N-type MOS transistor is electrically connected to the second path terminal of the P-type MOS transistor. The connection point between the second path terminal of the N-type MOS transistor and the second path terminal of the P-type MOS transistor constitutes the signal acquisition terminal of the detection switching unit and is electrically connected to the sensing trace.

[0021] In one embodiment, the impedance detection unit includes an impedance testing component and a storage component, wherein the impedance testing component is electrically connected to the storage component and the detection terminal of the detection switching unit, respectively.

[0022] In one embodiment, the pixel structure module includes a second thin-film transistor, a third thin-film transistor, a fourth thin-film transistor, a capacitor, and a light-emitting diode;

[0023] The gate of the second thin-film transistor is electrically connected to a preset first signal terminal, the first path terminal of the second thin-film transistor is electrically connected to a data line, the second path terminal of the second thin-film transistor is electrically connected to the gate of the third thin-film transistor, and the first terminal of the capacitor is disposed between the second path terminal of the second thin-film transistor and the gate of the third thin-film transistor.

[0024] The first terminal of the third thin-film transistor is electrically connected to the power supply terminal, the second terminal of the capacitor is disposed between the first terminal of the third thin-film transistor and the power supply terminal, the second terminal of the third thin-film transistor is electrically connected to the anode of the light-emitting diode, and the cathode of the light-emitting diode is electrically connected to the negative power supply terminal.

[0025] The gate of the fourth thin-film transistor is electrically connected to a preset second signal terminal, the first path terminal of the fourth thin-film transistor is disposed between the second path terminal of the third thin-film transistor and the anode of the light-emitting diode, and the second path terminal of the fourth thin-film transistor is electrically connected to the sensing trace.

[0026] Furthermore, to achieve the above objectives, this application also provides a driving method for a voltage detection display circuit, which is applied to the voltage detection display circuit described in any of the above claims, and the driving method for the voltage detection display circuit includes:

[0027] When the display driver module provides pixel power voltage to the pixel structure module through the voltage trace from the power supply terminal to the power supply access point, the impedance measurement module determines the voltage trace impedance of the pixel structure module based on the preset voltage detection signal and the pixel power voltage, and transmits the voltage trace impedance to the sensing trace through the impedance measurement module.

[0028] The display driver module obtains the voltage trace impedance sent by the impedance measurement module via the sensing trace, and determines the compensation voltage based on the normal display current of the pixel structure module and the voltage trace impedance. The compensation voltage is then superimposed on the pixel power supply voltage and connected to the power supply access point so that the pixel structure module can display normally.

[0029] In one embodiment, the step of obtaining the voltage trace impedance transmitted by the impedance measurement module via the sensing trace through the display driving module includes:

[0030] The display driver module accesses the actual trace impedance output by the sensor trace, and determines the sensor trace impedance corresponding to the sensor trace and the number of voltage trace paths.

[0031] The impedance difference between the actual trace impedance and the sensing trace impedance is determined, and the ratio between the impedance difference and the number of paths is used as the voltage trace impedance sent by the impedance measurement module.

[0032] In addition, to achieve the above objectives, this application also provides a display panel, the display panel including the voltage detection and display circuit described in any of the above claims.

[0033] Furthermore, to achieve the above objectives, this application also provides a display device, which includes the aforementioned display panel; or,

[0034] The display device includes a processor, a memory, and a driver program for a voltage-sensing display circuit stored in the memory and executable by the processor. When the driver program for the voltage-sensing display circuit is executed by the processor, it implements the steps of the above-described driving method for the voltage-sensing display circuit.

[0035] This application provides a voltage detection display circuit and its driving method, a display panel, and a display device, significantly improving the display quality of OLED products using the voltage detection display circuit. Specifically, the voltage detection display circuit of this application integrates a display driving module, an array of pixel structure modules, and an impedance measurement module and sensing traces electrically connected to the pixel structure modules. The pixel structure modules are electrically connected to the power supply terminal of the display driving module via their power supply access points. During the process where the display driving module provides the pixel power voltage to drive the pixel structure modules to emit light through the voltage trace path from the power supply terminal to the power supply access point, the impedance measurement module electrically connected to the power supply access point can monitor the voltage drop (i.e., IRDrop phenomenon) caused by the voltage trace path (i.e., metal trace) in real time by responding to a preset voltage detection signal. This allows for the rapid and accurate determination of the voltage trace impedance (i.e., metal trace resistance) of the pixel structure modules. The voltage trace impedance is transmitted to the signal output terminal of the impedance measurement module, which is electrically connected to the sensing trace. At this time, the sensing trace is electrically connected to the impedance detection terminal of the display driver module. After the display driver module receives the voltage trace impedance sent by the impedance measurement module through the sensing trace, it can accurately obtain the compensation voltage based on the voltage trace impedance and the normal display current of the pixel structure module. Then, the compensation voltage is superimposed on the pixel power supply voltage and connected to the power supply access point of the pixel structure module. This avoids the voltage drop phenomenon caused by the metal trace resistance, prevents the cumulative effect of voltage drop, and ensures that the pixel power supply voltage received by each pixel structure module in the array is consistent, which significantly improves the brightness uniformity of OLED products and thus improves the display quality of OLED products. Attached Figure Description

[0036] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0037] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 is a schematic diagram of uneven brightness display on the display panel;

[0039] Figure 2 shows the distribution of ELVDDs within the existing technology plane;

[0040] Figure 3 is a structural block diagram of the voltage detection and display circuit of the present application in a first embodiment;

[0041] Figure 4 is an in-plane wiring diagram of ELVDD according to an embodiment of the voltage detection and display circuit of this application;

[0042] Figure 5 is a circuit diagram of an embodiment of the voltage detection and display circuit of this application;

[0043] Figure 6 is a schematic diagram of a display driving module according to an embodiment of the voltage detection display circuit of this application;

[0044] Figure 7 is a simplified schematic diagram of the actual trace impedance involved in an embodiment of the voltage detection and display circuit of this application;

[0045] Figure 8 is a schematic diagram of voltage trace impedance calculation involved in the driving method of the voltage detection and display circuit of this application;

[0046] Figure 9 is a schematic diagram of the structure of the display device involved in the embodiment of this application.

[0047] Explanation of icon numbers:

[0048] 10. Display driver module; 20. Impedance measurement module; 30. Pixel structure module; Ls. Sensing trace; T1. First thin-film transistor; 101. Detection switching unit; 102. Impedance detection unit; 103. Sensing unit; 104. Timing control unit; T2. Second thin-film transistor; T3. Third thin-film transistor; T4. Fourth thin-film transistor; C1. Capacitor; D1. Light-emitting diode; Q1. N-type MOSFET; Q2. P-type MOSFET.

[0049] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0050] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0051] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0052] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0053] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application.

[0054] ELVDD is a crucial voltage signal in display panels, especially OLED (Organic Light-Emitting Diode) screens, representing the pixel power supply voltage. It is typically generated by the DDIC (Display Driver IC). The DDIC acts as a bridge between the upper-level application processor (CPU) and the OLED screen, responsible for converting image signals into control waveforms that the screen can receive. In this process, ELVDD, as one of the key voltages driving OLED pixel emission, has a significant impact on display performance due to its stability and uniformity.

[0055] However, in practical applications, referring to Figure 1, which is a schematic diagram of uneven brightness display on a display panel, ELVDD, after being generated from the DDIC, needs to be transmitted to each pixel position on the panel through a complex circuit layout and metal traces. Due to the resistance of the metal traces, a voltage drop occurs when current passes through, i.e., the IR Drop phenomenon. As the signal transmission distance increases, the voltage drop gradually accumulates, causing the ELVDD voltage received at the far end of the panel to be lower than that at the near end, thus causing the uneven brightness problem shown in Figure 1. For example, referring to Figure 2, which is a distribution diagram of ELVDD in the prior art, it can be seen that ELVDD is routed from far to near along the edge, and then enters the power supply access point of each pixel structure module row by row. Due to the voltage trace impedance Rp on the voltage trace path, the ELVDD voltage at the near end and the far end will be inconsistent. For example, the voltage Vn at the farthest end = the voltage V1 at the nearest end + I*(nRp), where n is the number of rows. This will cause the near-end pixels to appear too bright due to higher voltage, while the far-end pixels will appear too dark due to insufficient voltage. Especially when displaying pure white at 255 gray levels, this brightness difference can be as high as hundreds of nits (units of brightness). This loss of brightness will reduce the yield of the display screen and seriously affect the display quality.

[0056] To address the issue of uneven brightness caused by the resistance of metal traces, this application provides a voltage detection display circuit and its driving method, a display panel, and a display device.

[0057] This application provides a voltage detection and display circuit. Referring to FIG3, FIG3 is a structural block diagram of a first embodiment of the voltage detection and display circuit of this application. The voltage detection and display circuit includes a display driving module 10, an array-distributed pixel structure module 30, and an impedance measurement module 20 and a sensing trace Ls electrically connected to the pixel structure module 30. The power supply access point of the pixel structure module 30 is electrically connected to the power supply terminal of the display driving module 10 and the signal access terminal of the impedance measurement module 20, respectively. The signal output terminal of the impedance measurement module 20 is electrically connected to the impedance detection terminal of the display driving module 10 through the sensing trace Ls.

[0058] In this embodiment, an impedance measurement module 20 is provided at the power supply access point of each pixel structure module 30, and the signal access terminal of the impedance measurement module 20 is electrically connected to the power supply access point of the corresponding pixel structure module 30. When the display driving module 10 provides pixel power supply voltage to each pixel structure module 30 row by row, the impedance measurement module 20 electrically connected to each pixel structure module 30 confirms the voltage trace impedance between the power supply terminal of the display driving module 10 and the corresponding pixel structure module 30. Next, the signal output terminal of each impedance measurement module 20 is electrically connected to the impedance detection terminal of the display driving module 10 through the sensing trace Ls. After the display driving module 10 obtains the voltage trace impedance sent by each impedance measurement module 20 via the sensing trace Ls, it compensates the pixel power supply voltage based on the voltage trace impedance and the normal display current of the pixel structure module 30, so that the pixel power supply voltage received by each pixel structure module 30 in the array distribution is consistent, which significantly improves the brightness uniformity of the OLED product and thus improves the display quality of the OLED product.

[0059] It should be noted that there are multiple pixel structure modules 30, and multiple pixel structure modules 30 in the same row can be represented by pixel structure module 30-1, pixel structure module 30-2, ..., and pixel structure module 30-N. The impedance measurement module 20 corresponding to pixel structure module 30-1 is -1, the impedance measurement module 20 corresponding to pixel structure module 30-2 is -2, ..., and the impedance measurement module 20 corresponding to pixel structure module 30-N is -N.

[0060] The pixel power supply voltage can be represented by ELVDD as shown in Figure 3. For example, referring to Figure 4, which is an in-plane wiring diagram of ELVDD according to an embodiment of the voltage detection display circuit of this application, the minimum control unit shown in Figure 4 is the pixel structure module 30 and the impedance measurement module 20 electrically connected. Figure 4(a) shows that the display driving module 10 has two power supply terminals, i.e., two ELVDD voltage injection points; that is, current is supplied to the minimum control unit through the two ELVDD voltage injection points together. Figure 4(b) shows that only the left ELVDD voltage injection point supplies current to the minimum control unit. Figure 4(c) shows that only the right ELVDD voltage injection point supplies current to the minimum control unit; that is, there is at least one voltage trace path from the power supply terminal to the power supply access point. Furthermore, the in-plane wiring of ELVDD shown in Figure 4 is only one feasible implementation of this application, and this application does not impose any limitations here. In addition, as can be seen from Figure 4, the sensing trace Ls set in this application is relatively simple, consisting of only one conductive sensing line, i.e., only one sensing trace Ls is electrically connected to the minimum control unit.

[0061] The impedance measurement module 20 is configured to determine the voltage trace impedance of the pixel structure module 30 based on a preset voltage detection signal and the pixel power supply voltage when the display driving module 10 provides pixel power voltage to the pixel structure module 30 through the voltage trace from the power supply terminal to the power supply access point, and transmit the voltage trace impedance to the sensing trace Ls.

[0062] In this embodiment, when the display driving module 10 provides the pixel power supply voltage to the radial pixel structure module 30 through the voltage trace from the power supply terminal to the power supply access point, the impedance measurement module 20 determines the voltage trace impedance when the pixel power supply voltage is output through the voltage trace path from the power supply terminal to the power supply access point based on the response of the impedance measurement module 20 to the preset voltage detection signal. Then, the voltage trace impedance is transmitted to the display driving module 10 through the sensing trace Ls, thereby realizing the real-time and accurate monitoring of the voltage trace impedance by the display driving module 10, providing reliable data support for subsequent compensation of the pixel power supply voltage, thereby greatly improving the brightness uniformity of the display panel.

[0063] The display driving module 10 is configured to acquire the voltage trace impedance sent by the impedance measurement module 20 via the sensing trace Ls, determine a compensation voltage based on the normal display current of the pixel structure module 30 and the voltage trace impedance, and then connect the compensation voltage to the pixel power supply voltage and the power supply access point so that the pixel structure module 30 can display normally.

[0064] In this embodiment, since the sensing trace Ls is electrically connected to the impedance detection terminal of the display driving module 10, after the voltage trace impedance sent by the impedance measurement module 20 via the sensing trace Ls is received, the display driving module 10 can accurately obtain the compensation voltage based on the voltage trace impedance and the normal display current of the pixel structure module 30. The compensation voltage is then superimposed on the pixel power supply voltage and connected to the power supply access point of the pixel structure module 30. This ensures that each pixel structure module 30 in the array distribution receives a voltage that precisely meets its normal display requirements; that is, the pixel power supply voltage received by each pixel structure module 30 in the array distribution remains consistent. This significantly improves the brightness uniformity of the display panel.

[0065] In summary, this application provides a voltage detection display circuit and its driving method, a display panel, and a display device, significantly improving the display quality of OLED products using the voltage detection display circuit. Specifically, the voltage detection display circuit of this application integrates a display driving module 10, an array-distributed pixel structure module 30, and an impedance measurement module 20 and sensing traces Ls corresponding to the pixel structure module 30. The pixel structure module 30 is electrically connected to the power supply terminal of the display driving module 10 through its power supply access point. During the process where the display driving module 10 provides the pixel power voltage to drive the pixel structure module 30 to emit light through the voltage trace path from the power supply terminal to the power supply access point, the impedance measurement module 20, electrically connected to the power supply access point, can monitor in real time the voltage drop (i.e., IR) caused by the voltage trace path (i.e., metal trace) in response to a preset voltage detection signal. This allows for the rapid and accurate determination of the voltage trace impedance (i.e., metal trace resistance) of the pixel structure module 30. This voltage trace impedance is then transmitted to the sensing trace Ls electrically connected to the signal output terminal of the impedance measurement module 20. Since the sensing trace Ls is electrically connected to the impedance detection terminal of the display driver module 10, the display driver module 10, after receiving the voltage trace impedance from the impedance measurement module 20 via the sensing trace Ls, can accurately obtain the compensation voltage based on the voltage trace impedance and the normal display current of the pixel structure module 30. This compensation voltage is then superimposed on the pixel power supply voltage and connected to the power supply access point of the pixel structure module 30. This avoids voltage drop caused by metal trace resistance, prevents the cumulative effect of voltage drop, and ensures that the pixel power supply voltage received by each pixel structure module 30 in the array distribution remains consistent, significantly improving the brightness uniformity of the OLED product and thus enhancing the display quality of the OLED product.

[0066] Further, in some feasible embodiments, referring to FIG5, FIG5 is a circuit schematic diagram involving an embodiment of the voltage detection and display circuit of this application. The impedance measurement module 20 includes a first thin-film transistor T1 and a voltage detection signal terminal; the gate of the first thin-film transistor T1 is electrically connected to the voltage detection signal terminal; the first path terminal of the first thin-film transistor T1 constitutes the signal input terminal of the impedance measurement module 20 and is electrically connected to the power supply input terminal of the pixel structure module 30; the second path terminal of the first thin-film transistor T1 constitutes the signal output terminal of the impedance measurement module 20 and is electrically connected to the sensing trace Ls.

[0067] In this embodiment, when the gate of the first thin-film transistor T1 is connected to a preset voltage detection signal Y1, the first thin-film transistor T1 immediately switches from the off state to the on state. Thus, the pixel power supply voltage output through the voltage trace path from the power supply terminal to the power supply access point can be input to the impedance detection terminal of the display driving module 10 through the sensing trace Ls via the first thin-film transistor T1. This allows the display driving module 10 to accurately obtain the voltage trace impedance of the pixel structure module 30, providing reliable data support for subsequent compensation of the pixel power supply voltage, thereby greatly improving the brightness uniformity of the display panel.

[0068] In a specific embodiment, if the preset voltage detection signal Y1 changes from a low level to a high level, the gate of the first thin film transistor T1 responds to the voltage detection signal, thereby switching the first thin film transistor T1 from the off state to the on state.

[0069] Furthermore, in some other feasible embodiments, referring to FIG6, FIG6 is a schematic diagram of a display driving module 10 according to an embodiment of the voltage detection display circuit of this application. The display driving module 10 includes a detection switching unit 101, an impedance detection unit 102, a sensing unit 103, and a timing control unit 104; the sensing terminal of the detection switching unit 101 is electrically connected to the sensing unit 103, the detection terminal of the detection switching unit 101 is electrically connected to the impedance detection unit 102, and the control terminal of the detection switching unit 101 is electrically connected to the timing control unit 104; the signal acquisition terminal of the detection switching unit 101 constitutes the impedance detection terminal of the display driving module 10 and is electrically connected to the sensing trace Ls.

[0070] In this embodiment, when the timing control signal output by the timing control unit 104 switches from a high level to a low level, the detection switching unit 101 responds to the timing control signal representing the low level, connecting the impedance detection unit 102 to the sensing trace Ls, enabling the detection switching unit 101 to detect the actual trace impedance output by the sensing trace Ls. Next, after determining the sensing trace Ls impedance, based on the ratio between the impedance difference between the actual trace impedance and the sensing trace Ls impedance and the number of voltage trace paths, the voltage trace impedance sent by the impedance measurement module 20 can be accurately calculated, thereby providing reliable data support for subsequent compensation of pixel power supply voltage, thus greatly improving the brightness uniformity of the display panel.

[0071] It should be noted that the display driver module 10 can be understood as a DDIC (Display Driver IC).

[0072] The actual trace impedance can be represented by R_all as shown in Figure 7, which is the total impedance between the voltage trace impedance ELVDD_R and the sensor trace impedance Ls_sensor_R. Furthermore, RI_O shown in Figure 7 can be understood as the starting point of the DDIC output ELVDD voltage (i.e., the pixel power supply voltage); RI_I shown in Figure 7 can be understood as the LsIC input terminal of the sensor trace (i.e., the impedance detection terminal of the display driver module 10); and the test point T shown in Figure 7 is the connection node where the signal input terminal of the impedance measurement module 20 is electrically connected to the power supply access point of the pixel structure module 30.

[0073] In a specific embodiment, the sensor trace Ls impedance sensor_R set in this application can be a preset value, which can be customized according to application requirements; the sensor trace Ls impedance sensor_R can also be calculated according to a preset impedance calculation formula, wherein the preset impedance calculation formula is shown in the following formula (1).

[0074] sensor_R= ...Formula (1)

[0075] in, Represents resistivity, which is strongly correlated with the conductor material of the sensing trace Ls; L represents the trace length, which is the distance between the LsIC input terminal of the DDIC sensing trace and the test point T. This represents the cross-sectional area of ​​the sensing trace Ls; due to L and These are all fixed values. According to this impedance calculation formula, the sensor trace impedance Ls sensor_R of each pixel structure module 30 can be accurately calculated.

[0076] Further, in some feasible embodiments, referring to FIG6, the detection switching unit 101 includes an N-type MOS transistor Q1 and a P-type MOS transistor Q2; the gate of the N-type MOS transistor Q1 is electrically connected to the gate of the P-type MOS transistor Q2, and the connection node of the gate of the N-type MOS transistor Q1 being electrically connected to the gate of the P-type MOS transistor Q2 constitutes the control terminal of the detection switching unit 101 and is electrically connected to the timing control unit 104; the first path terminal of the N-type MOS transistor Q1 constitutes the sensing terminal of the detection switching unit 101 and is electrically connected to the sensing unit 103, the first path terminal of the P-type MOS transistor Q2 constitutes the detection terminal of the detection switching unit 101 and is electrically connected to the impedance detection unit 102; the second path terminal of the N-type MOS transistor Q1 is electrically connected to the second path terminal of the P-type MOS transistor Q2, and the connection intersection of the second path terminal of the N-type MOS transistor Q1 being electrically connected to the second path terminal of the P-type MOS transistor Q2 constitutes the signal acquisition terminal of the detection switching unit 101 and is electrically connected to the sensing trace Ls.

[0077] In this embodiment, the detection switching unit 101 provided in this application is used to switch whether the sensing trace Ls is in the Vth sensing stage or the ELVDD impedance detection stage. For example, when the timing control signal output by the timing control unit 104 is high, the P-type MOS transistor Q2 remains in the off state, and the N-type MOS transistor Q1 switches from the off state to the on state to connect the connection path from the sensing unit 103 to the sensing trace Ls, that is, the sensing trace Ls is in the Vth sensing stage. In other words, the fourth thin-film transistor T4 shown in FIG5 switches from the off state to the on state under the drive of the sensing signal output by the preset second signal terminal, so that the display driving module 10 electrically connected to the sensing trace Ls can detect the current flowing through the third thin-film transistor T3 or the anode potential of the light-emitting diode D1, thereby calculating the threshold voltage of the third thin-film transistor T3.

[0078] When the timing control signal output by the timing control unit 104 switches from a high level to a low level, the detection switching unit 101 responds to the timing control signal representing the low level, enabling the N-type MOS transistor Q1 to switch from the on state to the off state, and simultaneously switching the P-type MOS transistor Q2 from the off state to the on state to connect the impedance detection unit 102 to the sensing trace Ls, enabling the detection switching unit 101 to access the actual trace impedance output by the sensing trace Ls. Next, after determining the sensing trace Ls impedance, based on the impedance difference between the actual trace impedance and the sensing trace Ls impedance, and the ratio between the impedance difference and the number of voltage trace paths, the voltage trace impedance sent by the impedance measurement module 20 can be accurately calculated, thus providing reliable data support for subsequent compensation of pixel power supply voltage, thereby greatly improving the brightness uniformity of the display panel.

[0079] Furthermore, in some other feasible embodiments, referring to FIG6, the impedance detection unit 102 includes an impedance testing component and a storage component, wherein the impedance testing component is electrically connected to the storage component and the detection terminal of the detection switching unit 101, respectively.

[0080] In this embodiment, the impedance testing component provided in this application is the ELVDD trace impedance module. The ELVDD trace impedance module is configured to accurately calculate the voltage trace impedance sent by the impedance measurement module 20 based on the impedance difference between the actual trace impedance and the impedance of the sensing trace Ls, and the ratio between the voltage trace path number and the impedance difference between the actual trace impedance and the sensing trace Ls impedance. This provides reliable data support for subsequent compensation of pixel power supply voltage, thereby greatly improving the brightness uniformity of the display panel.

[0081] For example, based on the electrical connection between the impedance testing component and the storage component, after the impedance testing component determines the impedance value of the voltage trace impedance, the impedance value of the voltage trace impedance is sent to the storage component for storage. In addition, the storage component provided in this application can be understood as DRAM (Dynamic Random Access Memory), which is used to store the ELVDD impedance value (i.e., the impedance value of the voltage trace impedance) of each pixel structure module 30. The expression of the ELVDD impedance value is shown in formula (2).

[0082] ELVDD_R=(R_all) / n-sensor_R……Formula (2)

[0083] Wherein, ELVDD_R is the impedance value of the voltage trace; R_all represents the total impedance between the voltage trace impedance ELVDD_R and the sensor trace impedance Ls_R; n represents the number of voltage trace paths.

[0084] Further, in some feasible embodiments, referring to FIG5, the pixel structure module 30 includes a second thin-film transistor T2, a third thin-film transistor T3, a fourth thin-film transistor T4, a capacitor C1, and a light-emitting diode D1; the gate of the second thin-film transistor T2 is electrically connected to a preset first signal terminal, the first path terminal of the second thin-film transistor T2 is electrically connected to a data line, the second path terminal of the second thin-film transistor T2 is electrically connected to the gate of the third thin-film transistor T3, and the first terminal of the capacitor C1 is disposed between the second path terminal of the second thin-film transistor T2 and the gate of the third thin-film transistor T3; the third thin-film transistor T2... The first path terminal of the third thin-film transistor T3 is electrically connected to the power supply terminal. The second terminal of the capacitor C1 is located between the first path terminal of the third thin-film transistor T3 and the power supply terminal. The second path terminal of the third thin-film transistor T3 is electrically connected to the anode of the light-emitting diode D1, and the cathode of the light-emitting diode D1 is electrically connected to the negative power supply terminal. The gate of the fourth thin-film transistor T4 is electrically connected to a preset second signal terminal. The first path terminal of the fourth thin-film transistor T4 is located between the second path terminal of the third thin-film transistor T3 and the anode of the light-emitting diode D1. The second path terminal of the fourth thin-film transistor T4 is electrically connected to the sensing trace Ls.

[0085] In this embodiment, the second thin-film transistor T2 can be understood as a data control TFT, which is responsible for charging and discharging capacitor C1; the third thin-film transistor T3 can be understood as a drive control TFT, which is responsible for controlling the current reaching the light-emitting diode D1; the fourth thin-film transistor T4 can be understood as a sensing TFT, which is used to detect the current flowing through the third thin-film transistor T3 or the anode potential of the light-emitting diode D1, thereby calculating the threshold voltage of the third thin-film transistor T3.

[0086] It should be noted that the light-emitting diode D1 can be understood as an OLED device.

[0087] In a specific embodiment, the display driving module 10 calculates the compensation voltage of the pixel structure module 30. After this compensation voltage is connected to the data line Ld shown in Figure 5, which is electrically connected to the display driving module 10, the second thin-film transistor T2 is turned on under the drive of the charging signal of capacitor C1 output from the preset first signal terminal. The compensation voltage then discharges through capacitor C1 to the power supply access point of the pixel structure module 30, thereby compensating for the ELVDD voltage drop of the pixel structure module 30 and ensuring that the pixel power supply voltage received by each pixel structure module 30 in the array remains consistent. This significantly improves the brightness uniformity of the display panel.

[0088] In summary, the voltage detection and display circuit provided in this application, when applied to an OLED display screen, can confirm the voltage trace impedance between the ELVDD output point and each sub-pixel (i.e., pixel structure module 30) through the impedance measurement module 20. Next, the impedance value of the voltage trace impedance is stored through the storage component. Then, based on the normal display current required for normal display of each sub-pixel and the voltage trace impedance of that sub-pixel, the required compensation voltage is converted and superimposed on the data line to compensate for the ELVDD voltage drop of each sub-pixel. This allows the compensation voltage to be distributed to each point, compensating each sub-pixel and ensuring that the display brightness of each sub-pixel remains consistent, thereby significantly improving the brightness uniformity of the OLED display screen.

[0089] Furthermore, based on the first embodiment of the voltage detection and display circuit of this application, a second embodiment of the driving method of the voltage detection and display circuit of this application is proposed.

[0090] The voltage detection display circuit driving method of this application is applied to the display circuit of any of the above claims. The voltage detection display circuit driving method of this application is executed by a terminal device that compensates for the voltage trace impedance of each pixel of the display panel. The voltage detection display circuit driving method of this application includes the following implementation steps S10 to S20.

[0091] Step S10: When the display driver module 10 provides pixel power supply voltage to the pixel structure module 30 through the voltage trace from the power supply terminal to the power supply access point, the impedance measurement module 20 determines the voltage trace impedance of the pixel structure module 30 based on the preset voltage detection signal and the pixel power supply voltage, and transmits the voltage trace impedance to the sensing trace Ls through the impedance measurement module 20.

[0092] In this embodiment, when the display driving module 10 provides the pixel power supply voltage to the radial pixel structure module 30 through the voltage trace from the power supply terminal to the power supply access point, the impedance measurement module 20 determines the voltage trace impedance when the pixel power supply voltage is output through the voltage trace path from the power supply terminal to the power supply access point based on the response of the impedance measurement module 20 to the preset voltage detection signal. Then, the voltage trace impedance is transmitted to the display driving module 10 through the sensing trace Ls, thereby realizing the real-time and accurate monitoring of the voltage trace impedance by the display driving module 10, providing reliable data support for subsequent compensation of the pixel power supply voltage, thereby greatly improving the brightness uniformity of the display panel.

[0093] Step S20: The display driving module 10 obtains the voltage trace impedance sent by the impedance measurement module 20 via the sensing trace Ls, and determines the compensation voltage based on the normal display current of the pixel structure module 30 and the voltage trace impedance. The compensation voltage is then superimposed on the pixel power supply voltage and connected to the power supply access point so that the pixel structure module 30 can display normally.

[0094] In this embodiment, since the sensing trace Ls is electrically connected to the impedance detection terminal of the display driving module 10, after the voltage trace impedance sent by the impedance measurement module 20 via the sensing trace Ls is received, the display driving module 10 can accurately obtain the compensation voltage based on the voltage trace impedance and the normal display current of the pixel structure module 30. The compensation voltage is then superimposed on the pixel power supply voltage and connected to the power supply access point of the pixel structure module 30. This ensures that each pixel structure module 30 in the array distribution receives a voltage that precisely meets its normal display requirements; that is, the pixel power supply voltage received by each pixel structure module 30 in the array distribution remains consistent. This significantly improves the brightness uniformity of the display panel.

[0095] Furthermore, in some other feasible embodiments, the above step S20: obtaining the voltage trace impedance sent by the impedance measurement module 20 via the sensing trace Ls through the display driving module 10 may also include the following implementation steps S201 to S202.

[0096] Step S201: The actual trace impedance output by the sensing trace Ls is connected through the display driver module 10, and the sensing trace impedance Ls corresponding to the sensing trace Ls and the number of voltage trace paths are determined.

[0097] In this embodiment, when the display driving module 10 receives the actual trace impedance output by the sensor trace Ls, it simultaneously determines the impedance of the sensor trace Ls corresponding to the sensor trace Ls and the number of voltage trace paths. This provides accurate data support for the subsequent calculation of the impedance value of the voltage trace, enabling the display driving module 10 to fully understand the impedance status of the voltage trace path and providing strong support for subsequent voltage compensation and adjustment.

[0098] Step S202: Determine the impedance difference between the actual trace impedance and the sensing trace Ls impedance, and use the ratio between the impedance difference and the number of paths as the voltage trace impedance sent by the impedance measurement module 20.

[0099] In this embodiment, the display driving module 10 determines the impedance difference between the actual trace impedance and the sensing trace Ls impedance, which can accurately reflect the impedance change or loss on the voltage trace path. Next, this impedance difference is proportionally calculated with the number of voltage trace paths to obtain a proportional data that can accurately reflect the voltage impedance characteristics in the pixel structure module 30. This proportional data is used as the voltage trace impedance sent by the impedance measurement module 20, providing a reliable basis for subsequent accurate voltage compensation. This ensures the accuracy and effectiveness of voltage compensation, thereby significantly improving the brightness uniformity of OLED products.

[0100] In a specific embodiment, referring to Figure 8, which is a schematic diagram of voltage trace impedance calculation involved in the driving method of the voltage detection and display circuit of this application, for example, the number n of paths from DDIC_ELVDD to test point T is confirmed, which is generally 2. This standard is continuous independent channels + 1, that is, the current can be provided by this path alone. As shown in Figure 8, the number of paths n is 3. When testing R_all, redundant paths need to be disconnected, leaving only one path, such as the voltage trace path shown in Figures 4(b) and 4(c). At this time, the preset voltage detection signal output is high, and the first thin-film transistor T1 shown in Figure 5 is in the on state; the preset second signal terminal output is signal X2 at a low level, and the fourth thin-film transistor T4 shown in Figure 5 is in the off state. That is to say, the timing control signal output by the timing control unit 104 shown in Figure 6 is low, thereby controlling the sensing trace Ls to enter the ELVDD impedance detection stage; at this time, the DDIC measures R_all minus Sensor_R and divides by n, which is the voltage trace impedance ELVDD_R, and stores this voltage trace impedance ELVDD_R in DRAM; next, during normal display, confirm that the normal display current required by the pixel structure module 30 is... Therefore, the compensation voltage can be determined as follows: = *ELVDD_R, which means the normal display current required by the pixel structure module 30 and the voltage difference between point G and point T as shown in Figure 5. Related to the voltage drop at point T When the -ELVDD voltage drops, a compensation voltage boost is applied to the data line connected via the G-point potential. This ensures that each pixel structure module 30 in the array receives a consistent pixel power supply voltage, thereby significantly improving the brightness uniformity of the display panel.

[0101] In addition, this application also provides a display panel, the display panel including the voltage detection and display circuit of any of the above.

[0102] Furthermore, this application also provides a display device. Please refer to Figure 9, which is a schematic diagram of the structure of the display device involved in the embodiment of this application. Specifically, the display device in this embodiment may be a device for a repair method that locally runs the display circuit.

[0103] As shown in Figure 9, the display device in this embodiment may include: the display panel described above; or, a processor 1001, such as a CPU, a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen and an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface).

[0104] The memory 1005 is disposed on the main body of the display device. The memory 1005 stores a program that performs corresponding operations when executed by the processor 1001. The memory 1005 is also used to store parameters used by the display device. The memory 1005 can be a high-speed RAM or a stable, non-volatile memory, such as a disk drive. Optionally, the memory 1005 can also be a storage device independent of the aforementioned processor 1001.

[0105] Those skilled in the art will understand that the display device structure shown in FIG9 does not constitute a limitation on the display device, and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0106] As shown in Figure 9, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a repair program for the display circuit of a display device.

[0107] In the display device shown in Figure 9, the processor 1001 can be used to call the repair program of the display circuit of the display device stored in the memory 1005, and execute the steps of the display screen control method as described above.

[0108] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0109] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0110] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a display device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0111] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A voltage detection and display circuit, characterized in that, The voltage detection and display circuit includes a display driving module, an array of pixel structure modules, and an impedance measurement module and sensing traces electrically connected to the pixel structure modules. The power supply access point of the pixel structure module is electrically connected to the power supply terminal of the display driving module and the signal access terminal of the impedance measurement module, respectively. The signal output terminal of the impedance measurement module is electrically connected to the impedance detection terminal of the display driving module through the sensing traces. The impedance measurement module is configured to determine the voltage trace impedance of the pixel structure module based on a preset voltage detection signal and the pixel power supply voltage when the display driving module provides a pixel power supply voltage to the pixel structure module via the voltage trace from the power supply terminal to the power supply access point, and then transmit the voltage trace impedance to the sensing traces. The display driving module is configured to connect to the actual trace impedance output by the sensing trace, determine the sensing trace impedance corresponding to the sensing trace and the number of paths of the voltage trace, determine the impedance difference between the actual trace impedance and the sensing trace impedance, and use the ratio between the impedance difference and the number of paths as the voltage trace impedance; the display driving module is configured to acquire the voltage trace impedance sent by the impedance measurement module via the sensing trace, determine a compensation voltage based on the normal display current of the pixel structure module and the voltage trace impedance, add the compensation voltage to the pixel power supply voltage and connect it to the power supply access point for normal display of the pixel structure module, wherein the compensation voltage is the product of the normal display current and the voltage trace impedance.

2. The voltage detection and display circuit as described in claim 1, characterized in that, The impedance measurement module includes a first thin-film transistor and a voltage detection signal terminal; the gate of the first thin-film transistor is electrically connected to the voltage detection signal terminal; the first path terminal of the first thin-film transistor constitutes the signal input terminal of the impedance measurement module and is electrically connected to the power supply input terminal of the pixel structure module; the second path terminal of the first thin-film transistor constitutes the signal output terminal of the impedance measurement module and is electrically connected to the sensing trace.

3. The voltage detection and display circuit as described in claim 1, characterized in that, The display driving module includes a detection switching unit, an impedance detection unit, a sensing unit, and a timing control unit; the sensing terminal of the detection switching unit is electrically connected to the sensing unit, the detection terminal of the detection switching unit is electrically connected to the impedance detection unit, and the control terminal of the detection switching unit is electrically connected to the timing control unit; the signal acquisition terminal of the detection switching unit constitutes the impedance detection terminal of the display driving module and is electrically connected to the sensing trace.

4. The voltage detection and display circuit as described in claim 3, characterized in that, The detection switching unit includes an N-type MOS transistor and a P-type MOS transistor. The gate of the N-type MOS transistor is electrically connected to the gate of the P-type MOS transistor. The connection node between the gate of the N-type MOS transistor and the gate of the P-type MOS transistor constitutes the control terminal of the detection switching unit and is electrically connected to the timing control unit. The first path terminal of the N-type MOS transistor constitutes the sensing terminal of the detection switching unit and is electrically connected to the sensing unit. The first path terminal of the P-type MOS transistor constitutes the detection terminal of the detection switching unit and is electrically connected to the impedance detection unit. The second path terminal of the N-type MOS transistor is electrically connected to the second path terminal of the P-type MOS transistor. The connection intersection between the second path terminal of the N-type MOS transistor and the second path terminal of the P-type MOS transistor constitutes the signal acquisition terminal of the detection switching unit and is electrically connected to the sensing trace.

5. The voltage detection and display circuit as described in claim 3, characterized in that, The impedance detection unit includes an impedance testing component and a storage component, wherein the impedance testing component is electrically connected to the storage component and the detection terminal of the detection switching unit, respectively.

6. The voltage detection and display circuit as described in claim 1, characterized in that, The pixel structure module includes a second thin-film transistor (TFT), a third TFT, a fourth TFT, a capacitor, and a light-emitting diode (LED). The gate of the second TFT is electrically connected to a preset first signal terminal, the first path terminal of the second TFT is electrically connected to a data line, and the second path terminal of the second TFT is electrically connected to the gate of the third TFT. The first terminal of the capacitor is located between the second path terminal of the second TFT and the gate of the third TFT. The first path terminal of the third TFT is electrically connected to a power supply terminal, the second terminal of the capacitor is located between the first path terminal of the third TFT and the power supply terminal, the second path terminal of the third TFT is electrically connected to the anode of the LED, and the cathode of the LED is electrically connected to a negative power supply terminal. The gate of the fourth TFT is electrically connected to a preset second signal terminal, the first path terminal of the fourth TFT is located between the second path terminal of the third TFT and the anode of the LED, and the second path terminal of the fourth TFT is electrically connected to the sensing trace.

7. A driving method for a voltage detection and display circuit, characterized in that, The driving method of the voltage detection display circuit is applied to the voltage detection display circuit as described in any one of claims 1 to 6. The driving method of the voltage detection display circuit includes: when the display driving module provides a pixel power supply voltage to the pixel structure module through the voltage trace from the power supply terminal to the power supply access point, the impedance measurement module determines the voltage trace impedance of the pixel structure module based on a preset voltage detection signal and the pixel power supply voltage, and transmits the voltage trace impedance to the sensing trace through the impedance measurement module; the display driving module obtains the voltage trace impedance transmitted by the impedance measurement module through the sensing trace, and based on the pixel structure... The normal display current of the module and the voltage trace impedance determine the compensation voltage. The compensation voltage is superimposed on the pixel power supply voltage and then connected to the power supply access point to enable the pixel structure module to display normally. The compensation voltage is the product of the normal display current and the voltage trace impedance. The display driving module is configured to connect to the actual trace impedance output by the sensing trace, and determines the sensing trace impedance corresponding to the sensing trace and the number of voltage trace paths. The impedance difference between the actual trace impedance and the sensing trace impedance is determined, and the ratio between the impedance difference and the number of paths is used as the voltage trace impedance.

8. The driving method for the voltage detection and display circuit as described in claim 7, characterized in that, The step of obtaining the voltage trace impedance sent by the impedance measurement module via the sensing trace through the display driving module includes: accessing the actual trace impedance output by the sensing trace through the display driving module, and determining the sensing trace impedance corresponding to the sensing trace and the number of voltage trace paths; determining the impedance difference between the actual trace impedance and the sensing trace impedance, and using the ratio between the impedance difference and the number of paths as the voltage trace impedance sent by the impedance measurement module.

9. A display panel, characterized in that, The display panel includes the voltage detection and display circuit according to any one of claims 1 to 6.

10. A display device, characterized in that, The display device includes the display panel of claim 9; or, the display device includes a processor, a memory, and a driver for a voltage-sensing display circuit stored in the memory and executable by the processor, wherein when the driver for the voltage-sensing display circuit is executed by the processor, the steps of the driving method for the voltage-sensing display circuit as described in any one of claims 7 to 8 are implemented.

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