Pixel display driving circuit and display panel

Abstract

The present application belongs to the field of display technology and provides a pixel driving circuit and a display panel. A data voltage is connected through a compensation circuit, the data voltage is compared with at least one reference voltage, and the target voltage range of the data voltage is determined based on the comparison result, and a compensated direct current is output according to the target voltage range. The pixel driving circuit responds to the connection of a selection signal and outputs a driving current according to the data voltage and the compensated direct current to illuminate a light-emitting element. The current of the compensated direct current is negatively correlated with the value in the target voltage range. Therefore, the driving capability of the row scanning driving circuit is enhanced, thereby reducing the possibility of parasitic parameters RC affecting the signal and improving the accuracy of data voltage transmission.

Description

Technical Field

[0001] The present application belongs to the field of display technology, and in particular relates to a pixel display driving circuit and a display panel. Background Art

[0002] With the continuous advancement of technology, organic light-emitting diodes (OLEDs) have gradually become a highly sought-after display technology, with an increasing number of display products now adopting OLEDs as their display screens. Compared to traditional liquid crystal display (LCD) display technology, OLEDs are self-luminous and do not require an additional backlight module, resulting in very low energy consumption. OLEDs also offer many advantages, including high brightness, high contrast, wide viewing angles, fast response speeds, and simple manufacturing processes. They are currently widely used in various display panels and have broad application prospects.

[0003] Currently, OLEDs are driven by thin-film field-effect transistors (TFTs). The RC delay generated by the parasitic parameters of the TFT devices in the circuit causes the rising and falling edges of the output pulse to lengthen, severely impacting the driving capability of the output pulses and, consequently, the accuracy of the OLED's light emission. To fundamentally reduce the impact of RC delay, it is necessary to address the TFT manufacturing process and materials. This involves developing high-conductivity interconnect materials for the TFT's metal gate and source / drain electrodes to reduce parasitic resistance. Alternatively, the overlap area between the source / drain and gate electrodes in the TFT can be reduced to minimize the parasitic capacitance of the TFT itself. Furthermore, optimization can be performed at the TFT layout design level to reduce the contact resistance in the metal-to-metal contact holes or the parasitic capacitance between different metal layers, thereby reducing the signal delay caused by parasitic RC. However, these TFT manufacturing process and material improvements are extremely complex.

[0004] Therefore, it is urgent to provide a pixel display driving circuit to enhance the driving capability of the row scanning driving circuit, thereby reducing the influence of the parasitic parameter RC on the signal and improving the accuracy of data voltage transmission. Summary of the Invention

[0005] The purpose of this application is to provide a pixel display driving circuit and a display panel, aiming to enhance the driving capability of the row scanning driving circuit, thereby solving the problem of the influence of parasitic parameters RC on the signal and improving the accuracy of data voltage transmission.

[0006] An embodiment of the present application provides a pixel display driving circuit, comprising:

[0007] a compensation circuit configured to receive a data voltage, compare the data voltage with at least one reference voltage, determine a target voltage interval within which the data voltage falls based on the comparison result, and output a compensation DC current based on the target voltage interval;

[0008] a pixel driving circuit connected to the compensation circuit and configured to output a driving current to the light-emitting element according to the data voltage and the compensation DC power in response to input of a selection signal, so as to light up the light-emitting element;

[0009] The current of the compensation direct current is negatively correlated with the value in the target voltage range.

[0010] In one embodiment, the compensation circuit includes n comparators, n-1 P-type switching tubes, n N-type switching tubes, n-1 switching elements and n compensation modules;

[0011] The non-inverting input terminal of the first comparator and the first terminals of n-1 P-type switching transistors serve as the data voltage input terminal of the compensation circuit to receive the data voltage; the inverting input terminal of the i-th comparator serves as the i-th reference voltage input terminal of the compensation circuit to receive the i-th reference voltage;

[0012] The output end of the (i+1)th comparator is connected to the control end of the (i+1)th P-type switching tube, the control end of the (i+1)th N-type switching tube, and the control end of the (i)th switching element; the output end of the first comparator is connected to the control end of the (1)th P-type switching tube and the control end of the (1)th N-type switching tube;

[0013] The first ends of the n N-type switching tubes also serve as the data voltage input end of the compensation circuit to receive the data voltage;

[0014] The second ends of the n N-type switching tubes are commonly connected to the input end of the first compensation module;

[0015] The i-th switching element is connected between the i-th compensation module and the (i+1)-th compensation module;

[0016] The compensation module amplifies the current of the input data voltage to output the data voltage after current amplification;

[0017] Wherein, i is a positive integer less than n, and n is a positive integer.

[0018] In one embodiment, the compensation module includes an even number of cascaded inverters; the first inverter to the last inverter are connected in sequence;

[0019] Wherein, the input terminal of the first inverter serves as the data voltage input terminal of the compensation module to access the data voltage;

[0020] The output end of the last inverter serves as the data voltage output end after current amplification of the compensation module to output the data voltage after current amplification.

[0021] In one embodiment, the first reference voltage to the nth reference voltage decrease in sequence.

[0022] In one embodiment, n is positively correlated with a transmission distance, where the transmission distance is the distance between the data voltage output terminal and the pixel driving circuit.

[0023] In one embodiment, the pixel display driving circuit further includes:

[0024] an amplifying circuit, connected to the pixel driving circuit and the compensation circuit, and configured to amplify the data voltage to output the amplified data voltage;

[0025] The compensation circuit is specifically configured to compare the amplified data voltage with at least one reference voltage, determine the target voltage interval of the data voltage according to the comparison result, and output the compensation DC power according to the target voltage interval.

[0026] In one embodiment, the pixel driving circuit includes:

[0027] a first switch circuit connected to the compensation circuit and configured to transmit the data voltage in response to access of the selection signal;

[0028] an energy storage circuit connected to the first switch circuit and the compensation circuit, and configured to be charged according to the data voltage, the compensation DC power, and the power supply DC power to output an energy storage voltage;

[0029] The second switching circuit is connected to the first switching circuit, the energy storage circuit and the compensation circuit, and is configured to transmit the supply DC power according to the energy storage voltage to output the driving current.

[0030] In one embodiment, the first switch circuit includes a first field effect transistor, the second switch circuit includes a second field effect transistor, and the energy storage circuit includes a first capacitor.

[0031] In one embodiment, the pixel display driving circuit includes a plurality of pixel driving components, and each pixel driving component includes one compensation circuit and a plurality of pixel driving circuits.

[0032] An embodiment of the present invention further provides a display panel, which includes the above-mentioned pixel display driving circuit and light-emitting elements.

[0033] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: since the compensation circuit is connected to the data voltage, the data voltage is compared with at least one reference voltage, and the target voltage range of the data voltage is determined according to the comparison result, and the compensated DC power is output according to the target voltage range; the pixel driving circuit responds to the connection of the selection signal and outputs the driving current according to the data voltage and the compensated DC power to illuminate the light-emitting element; the superimposed data voltage and the compensated DC power are applied to the pixel driving circuit to output the driving current, thereby enhancing the driving capability of the row scanning driving circuit and reducing the possibility of the parasitic parameter RC affecting the signal; and the current of the compensated DC power is negatively correlated with the value in the target voltage range, thereby accelerating the charging and discharging of the RC circuit while improving the accuracy of the current compensation of the pixel display driving circuit, improving the stability of the OLED light emitting brightness, and improving the accuracy of data voltage transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical inventions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] Figure 1 A schematic structural diagram of a pixel display driving circuit provided in one embodiment of the present application;

[0036] Figure 2 A schematic diagram of a first structure of a compensation circuit in a pixel display driving circuit provided in an embodiment of the present application;

[0037] Figure 3 Another structural diagram of a pixel display driving circuit provided in an embodiment of the present application;

[0038] Figure 4 Another structural diagram of a pixel display driving circuit provided in an embodiment of the present application;

[0039] Figure 5 Another structural diagram of a pixel display driving circuit provided in an embodiment of the present application;

[0040] Figure 6 A second structural diagram of a compensation circuit in a pixel display driving circuit provided in an embodiment of the present application;

[0041] Figure 7 A schematic structural diagram of a pixel driving circuit in a pixel display driving circuit provided in an embodiment of the present application;

[0042] Figure 8A partial exemplary circuit schematic diagram of a pixel display driving circuit provided in one embodiment of the present application;

[0043] Figure 9 A partial exemplary circuit diagram of a compensation module in a pixel display driving circuit provided in an embodiment of the present application;

[0044] Figure 10 A partial exemplary circuit schematic diagram of a pixel driving circuit in a pixel display driving circuit provided in an embodiment of the present application;

[0045] Figure 11 This is a waveform diagram of a selection signal provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0047] It should be noted that when an element is referred to as being “fixed on” or “disposed on” another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being “connected to” another element, it may be directly connected to the other element or indirectly connected to the other element.

[0048] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0050] Figure 1 The following is a schematic diagram showing the structure of a pixel display driving circuit provided by a preferred embodiment of the present application. For ease of explanation, only the parts related to this embodiment are shown, which are described in detail as follows:

[0051] The pixel display driving circuit includes a compensation circuit 11 and a pixel driving circuit 12 .

[0052] The compensation circuit 11 is configured to receive the data voltage Dm, compare the data voltage Dm with at least one reference voltage Vrefi, determine the target voltage range of the data voltage Dm according to the comparison result, and output a compensation DC current according to the target voltage range.

[0053] The pixel driving circuit 12 is connected to the compensation circuit 11 and is configured to output a driving current to the light emitting element according to the data voltage Dm and the compensation DC power in response to the input of the selection signal Sn, so as to light up the light emitting element.

[0054] The current of the compensation DC power is negatively correlated with the value in the target voltage range.

[0055] It should be noted that the selection signal Sn and the data voltage Dm can be provided by a digital circuit.

[0056] By way of example and not limitation, the at least one reference voltage Vrefi includes a first reference voltage Vref1 to an nth reference voltage Vrefn, which decrease in sequence. The first voltage interval is defined as a range greater than or equal to the first reference voltage Vref1, the second voltage interval is defined as a range less than the first reference voltage Vref1 and greater than or equal to the second reference voltage Vref2, and the third voltage interval is defined as a range less than the second reference voltage Vref2 and greater than or equal to the third reference voltage Vref3. Similarly, the nth voltage interval is defined as a range less than the n-1th reference voltage Vrefn-1 and greater than or equal to the nth reference voltage Vrefn, and the n+1th voltage interval is defined as a range less than the nth reference voltage Vrefn. The target voltage interval is one of the first to n+1th voltage intervals. When the data voltage Dm is in the first voltage interval, the compensation DC current is minimum; when the data voltage Dm is in the N+1 voltage interval, the compensation DC current is maximum. That is, as the value of the voltage interval increases, the current of the compensation DC current decreases. n is a positive integer, and i is a positive integer less than or equal to n.

[0057] By making the current of the compensation DC negatively correlated with the value in the target voltage range, the data voltage Dm is negatively correlated with the current of the compensation DC. On the rising edge, as the data voltage Dm increases, the compensation DC decreases; on the falling edge, the data voltage Dm decreases and the compensation DC increases. While accelerating the charging and discharging of the RC circuit, the accuracy of the current compensation of the pixel display driving circuit is improved, and the stability of the OLED light emitting brightness is improved.

[0058] like Figure 2 As shown, the compensation circuit 11 includes n comparators Ui, n−1 P-type switching transistors Pi, n N-type switching transistors Ni, n−1 switching elements Ki and n compensation modules 111 .

[0059] The positive input terminal of the first comparator U1 and the first terminals of the n-1 P-type switch tubes Pi serve as the data voltage input terminal of the compensation circuit 11 to connect the data voltage Dm; the negative input terminal of the i-th comparator Ui serves as the i-th reference voltage Vrefi input terminal of the compensation circuit 11 to connect the i-th reference voltage Vrefi.

[0060] The output end of the i+1th comparator Ui+1 is connected to the control end of the i+1th P-type switching tube Pi+1, the control end of the i+1th N-type switching tube Ni+1, and the control end of the i-th switching element Ki; the output end of the first comparator U1 is connected to the control end of the first P-type switching tube P1 and the control end of the first N-type switching tube N1.

[0061] The first terminals of the n N-type switching transistors Ni also serve as the data voltage input terminal of the compensation circuit 11 to receive the data voltage Dm.

[0062] The second ends of the n N-type switching transistors Ni are commonly connected to the input end of the first compensation module 111 .

[0063] The i-th switching element Ki is connected between the i-th compensation module 111 and the (i+1)-th compensation module 111 .

[0064] The compensation module 111 amplifies the current of the input data voltage Dm to output the amplified data voltage Dm.

[0065] Wherein, i is a positive integer less than n, and n is a positive integer.

[0066] For example, when the data voltage Dm is greater than or equal to the first reference voltage Vref1, the first comparator U1 outputs a high-level signal, turning on the first N-type switch N1 and turning off the first P-type switch P1; the first compensation module 111 operates according to the data voltage Dm transmitted by the first N-type switch N1, and outputs the data voltage Dm2 after current amplification; the second comparator U2 to the n-th comparator Un output low-level signals, turning off the second N-type switch N2 to the n-th N-type switch Nn, turning off the first switch element K1 to the n-1-th switch element Kn-1, and stopping the second compensation module 111 to the n-th compensation module 111. Therefore, the data voltage Dm is only amplified by the first compensation module 111 to output the compensated DC power to the pixel driving circuit 12.

[0067] When the data voltage Dm is greater than or equal to the second reference voltage Vref2 and less than the first reference voltage Vref1, the first comparator U1 outputs a low-level signal to turn off the first N-type switch N1 and turn on the first P-type switch P1; the second comparator U2 outputs a high-level signal to turn on the second N-type switch N2 and the first switch element K1 and turn off the second P-type switch P2; the first compensation module 111 and the second compensation module 111 are based on the data voltage Dm transmitted by the second N-type switch N2. The third comparator U3 to the nth comparator Un output low-level signals, the third N-type switch tube N3 to the nth N-type switch tube Nn are turned off, the second switch element K2 to the n-1th switch element Kn-1 are turned off, and the third compensation module 111 to the n-th compensation module 111 stop working. Therefore, the data voltage Dm is only amplified by the two-stage current of the first compensation module 111 and the second compensation module 111 to output the compensated DC power to the pixel driving circuit 12.

[0068] By analogy, when the data voltage Dm is greater than or equal to the third reference voltage Vref3 and less than the second reference voltage Vref2, the data voltage Dm is amplified by three stages of current through the first compensation module 111, the second compensation module 111, and the third compensation module 111 to output a compensated direct current to the pixel driving circuit 12; until the data voltage Dm is less than or equal to the n-1th reference voltage Vrefn-1 and greater than the nth reference voltage Vrefn, the data voltage Dm is amplified by n stages of current through the n compensation modules 111 to output a compensated direct current to the pixel driving circuit 12.

[0069] The data voltage Dm is compared by n comparators Ui to determine the target voltage range of the data voltage Dm, and the corresponding number of compensation modules 111 are turned on according to the target voltage range to amplify the current of the data voltage Dm by the corresponding number of levels to output a compensated direct current, thereby achieving a negative correlation between the current of the compensated direct current and the value in the target voltage range.

[0070] As an example but not a limitation, the compensation module 111 includes an even number of cascaded inverters; the first inverter to the last inverter are connected in sequence.

[0071] The input end of the first inverter serves as the data voltage input end of the compensation module to receive the data voltage; the output end of the last inverter serves as the data voltage output end of the compensation module after current amplification to output the data voltage after current amplification.

[0072] The compensation module 111 is realized by an even number of cascaded inverters, which has a simple circuit structure and low cost.

[0073] It should be emphasized that the first reference voltage Vref1 to the nth reference voltage Vrefn decrease in sequence.

[0074] Since the first reference voltage Vref1 to the nth reference voltage Vrefn decrease in sequence, the smaller the data voltage Dm is, the more compensation circuits 11 are turned on, the more levels of current amplification of the data voltage Dm are, and the larger the compensation DC current is, thereby improving the accuracy of current compensation in the pixel driving circuit.

[0075] It is worth emphasizing that the pixel display driving circuit may include multiple groups of pixel driving components, each group of pixel driving components includes a compensation circuit and multiple pixel driving circuits. By sharing a part of the compensation circuit, the circuit can be simplified and the pixel aperture ratio can be improved, thereby reducing costs. For example, a row of pixel circuits share one compensation circuit. Figure 3 As shown, there are n rows of pixel circuits (light-emitting elements 90), each row of pixel circuits includes m pixel circuits, n compensation circuits 11 correspond one-to-one to the n rows of pixel circuits, and each compensation circuit 11 is connected to m pixel driving circuits 12; corresponding to each row of pixel circuits, m pixel driving circuits 12 are connected one-to-one to m pixel circuits. It is understood that the pixel display driving circuit 12 also includes a microprocessor 100.

[0076] The microprocessor 100 is configured to access the data voltages of each row of pixel circuits, and when the data voltages of more than half of the pixel circuits in each row of pixel circuits are less than a threshold value, output an enable signal and a target data voltage corresponding to each row of pixel circuits, wherein the target data voltage is the average value of the data voltages of the pixel circuits in each row of pixel circuits or the median of the data voltages of the pixel circuits in each row of pixel circuits; the compensation circuit 11 is specifically configured to access the target data voltage, compare the target data voltage with at least one reference voltage Vrefi according to the enable signal, determine the target voltage range in which the target data voltage is located according to the comparison result, and output a compensated DC power according to the target voltage range; thereby, each pixel driving circuit 12 outputs a driving current to each light-emitting element according to the data voltage Dm and the compensated DC power in response to the access of the selection signal, so as to light up each light-emitting element.

[0077] It should be noted that n is positively correlated with the transmission distance, which is the distance between the output terminal of the data voltage Dm and the pixel driving circuit 12 .

[0078] In a specific implementation, the greater the distance between the output terminal of the data voltage Dm and the pixel driving circuit 12, the greater the attenuation of the data voltage Dm, and the smaller the attenuated data voltage Dm. Therefore, more compensation modules 111 are required for compensation to amplify the current of the data voltage Dm by more levels.

[0079] As an example and not a limitation, starting from the Chip On Film (COF), the data voltage of the near-end pixel circuit has almost no attenuation, and no compensation circuit is required; the farthest end requires a compensation circuit with the maximum number of levels (n), such as 3 levels of compensation; from near to far, the number of compensation circuits increases successively. In one embodiment, the display panel can be divided into zones according to the distance from the COF, and different zones use different compensation circuit designs. Figure 4 As shown, the pixel circuits on the display panel are divided into regions 1, 2 to k from near to far from the COF; the level of the compensation circuit corresponding to each region is positively correlated with the distance of each region from the COF; for example, region 1 can be set to no compensation, region 2 can be set to 1 level of compensation, region 3 can be set to 2 levels of compensation, and region 4 can be set to 3 levels of compensation.

[0080] While setting n to be positively correlated with the transmission distance, each pixel driving component can be configured to include a compensation circuit and multiple pixel driving circuits, thereby further improving the aperture ratio, simplifying the circuit, and reducing costs.

[0081] like Figure 5 As shown, the pixel driving circuit further includes an amplifier circuit 13 .

[0082] The amplifier circuit 13 is connected to the pixel driving circuit 12 and the compensation circuit 11 , and is configured to amplify the data voltage Dm to output the amplified data voltage Dm.

[0083] The compensation circuit 11 is specifically configured to compare the amplified data voltage Dm with at least one reference voltage Vrefi, determine the target voltage interval of the data voltage Dm according to the comparison result, and output the compensation DC power according to the target voltage interval.

[0084] By amplifying the data voltage Dm and comparing the amplified data voltage Dm with at least one reference voltage Vrefi, each voltage interval is increased, which is beneficial to circuit parameter design and device selection and facilitates circuit design.

[0085] In such Figure 5 In the pixel display driving circuit shown in FIG. 1 , the compensation circuit 11 can be as follows: Figure 6 As shown, it includes n comparators Ui, n-1 P-type switching tubes Pi, n N-type switching tubes Ni, n-1 switching elements Ki and n compensation modules 111.

[0086] The positive input terminal of the first comparator U1 and the first terminals of the n-1 P-type switching tubes Pi serve together as the amplified data voltage input terminal of the compensation circuit 11 to receive the amplified data voltage Dm2; the inverting input terminal of the i-th comparator Ui serves as the i-th reference voltage input terminal of the compensation circuit 11 to receive the i-th reference voltage Vrefi.

[0087] The output end of the i+1th comparator Ui+1 is connected to the control end of the i+1th P-type switching tube Pi+1, the control end of the i+1th N-type switching tube Ni+1, and the control end of the i-th switching element Ki; the output end of the first comparator U1 is connected to the control end of the first P-type switching tube P1 and the control end of the first N-type switching tube N1.

[0088] The first terminals of the n N-type switching transistors Ni serve together as the data voltage input terminal of the compensation circuit 11 to receive the data voltage Dm.

[0089] The second ends of the n N-type switching transistors Ni are commonly connected to the input end of the first compensation module 111 .

[0090] The i-th switching element Ki is connected between the i-th compensation module 111 and the (i+1)-th compensation module 111 .

[0091] The compensation module 111 amplifies the current of the input data voltage Dm to output the amplified data voltage Dm.

[0092] Wherein, i is a positive integer less than n, and n is a positive integer.

[0093] It is worth noting that Figure 4 The compensation circuit 11 shown is similar to the Figure 3 The difference of the compensation circuit 11 shown is that the non-inverting input terminal of the first comparator Ui and the first terminals of n-1 P-type switches Pi serve as the amplified data voltage Dm input terminal of the compensation circuit 11 to receive the amplified data voltage Dm.

[0094] Therefore Figure 6 The n comparators Ui shown compare the amplified data voltage Dm, determine the target voltage range of the amplified data voltage Dm, and turn on the corresponding number of compensation modules 111 according to the target voltage range to amplify the current of the data voltage Dm by the corresponding number of levels to output compensated direct current, thereby achieving a negative correlation between the current of the compensated direct current and the value in the target voltage range.

[0095] like Figure 7 As shown, the pixel driving circuit 12 includes a first switch circuit 121 , a tank circuit 122 and a second switch circuit 123 .

[0096] The first switch circuit 121 is connected to the compensation circuit 11 and configured to transmit the data voltage Dm in response to the input of the selection signal Sn.

[0097] The energy storage circuit 122 is connected to the first switch circuit 121 and the compensation circuit 11 , and is configured to be charged according to the data voltage Dm, the compensation DC power and the power supply DC power to output an energy storage voltage.

[0098] The second switch circuit 123 is connected to the first switch circuit 121 , the energy storage circuit 122 and the compensation circuit 11 , and is configured to transmit a power supply DC according to the energy storage voltage to output a driving current.

[0099] It should be noted that the first switch circuit 121, the energy storage circuit 122, and the second switch circuit 123 are commonly connected to the first node A. The compensation circuit is specifically configured to, in response to the voltage of the first node A being less than or equal to a preset value, connect the data voltage, compare the data voltage with at least one reference voltage, determine the target voltage range within which the data voltage falls based on the comparison result, and output the compensation DC power according to the target voltage range.

[0100] The pixel selection function and the pixel driving function are realized by the first switch circuit 121 , the energy storage circuit 122 and the second switch circuit 123 .

[0101] Figure 8 FIG1 shows a partial exemplary circuit structure of a pixel driving circuit in a pixel display driving circuit provided by an embodiment of the present invention. Figure 9 FIG1 shows a partial exemplary circuit structure of a compensation module in a pixel display driving circuit provided by an embodiment of the present invention. Figure 10 A partial exemplary circuit structure of an amplifier circuit in a pixel display driving circuit provided by an embodiment of the present invention is shown. For ease of explanation, only the portion related to the embodiment of the present invention is shown, and the details are as follows:

[0102] like Figure 8 As shown, the first switch circuit 121 includes a first field effect transistor M1; the gate of the first field effect transistor M1 serves as a selection signal input terminal of the first switch circuit 121 to receive the selection signal Sn; the drain of the first field effect transistor M1 serves as a data voltage input terminal of the first switch circuit 121 to receive the data voltage Dm; and the source of the first field effect transistor M1 serves as a data voltage output terminal of the first switch circuit 121 to output the data voltage Dm.

[0103] The second switching circuit 123 includes a second field-effect transistor M2; the gate of the second field-effect transistor M2 and the source of the second field-effect transistor M2 serve as the energy storage voltage input terminal of the second switching circuit 123, and are connected to the energy storage circuit 122 to receive the energy storage voltage; the source of the second field-effect transistor M2 also serves as the power supply DC input terminal of the second switching circuit 123 to receive the power supply DC; the drain of the second field-effect transistor M2 serves as the drive current output terminal of the second switching circuit 123, and is connected to the light-emitting element to output the drive current.

[0104] The energy tank circuit 122 includes a first capacitor C1. The first end of the first capacitor C1 serves as the DC power input terminal of the energy tank circuit 122 to receive the DC power supply. The first end of the first capacitor C1 serves as the data voltage input terminal and the compensation DC power input terminal of the energy tank circuit 122, connected to the first switch circuit 121 and the second switch circuit 123 to receive the data voltage Dm and the compensation DC power. The first end of the first capacitor C1 and the second end of the first capacitor C1 serve as the energy tank voltage output terminal of the energy tank circuit 122, connected to the second switch circuit 123 to output the energy tank voltage.

[0105] like Figure 9 As shown, the compensation module 111 includes a first inverter IVT1 and a second inverter IVT2; the input end of the first inverter IVT1 serves as the data voltage input end of the compensation module 111 to receive the data voltage Dm; the output end of the first inverter IVT1 is connected to the input end of the second inverter IVT2; the output end of the second inverter IVT2 serves as the data voltage output end after current amplification of the compensation module 111 to receive the data voltage Dm after current amplification; the power supply end of the first inverter IVT1 and the power supply end of the second inverter IVT2 are commonly connected to the first power supply VAA; the ground end of the first inverter IVT1 and the ground end of the second inverter IVT2 are commonly connected to the power ground.

[0106] like Figure 10 As shown, the amplifier circuit 13 includes an operational amplifier X1, a third field-effect transistor M3, a first resistor R1, a second resistor R2, and a third resistor R3; the gate of the third field-effect transistor M3 serves as a selection signal input terminal of the amplifier circuit 13, connected to the pixel driving circuit 12 to receive the selection signal Sn; the drain of the third field-effect transistor M3 serves as a data voltage input terminal of the amplifier circuit 13, connected to the pixel driving circuit 12 to receive the data voltage Dm; the source of the third field-effect transistor M3 is connected to the first end of the third resistor R3, the second end of the third resistor R3 is connected to the non-inverting input terminal of the operational amplifier X1, the inverting input terminal of the operational amplifier X1 is connected to the first end of the first resistor R1 and the first end of the second resistor R2, the second end of the first resistor R1 and the output terminal of the operational amplifier X1 jointly serve as the amplified data voltage output terminal of the amplifier circuit 13, connected to the compensation circuit 11 to output the amplified data voltage Dm2; the second end of the second resistor R2 is connected to the power ground.

[0107] The following is combined with the working principle Figures 8 to 10 As shown for further explanation:

[0108] It should be noted that in the relevant pixel driving circuit 12, the selection signal Sn controls the switch of the first field effect transistor M1, causing the first field effect transistor M1 to transmit the data voltage Dm to the first node A to charge the first capacitor C1. The energy storage voltage across the first capacitor C1 controls the degree of conduction of the second field effect transistor M2, thereby controlling the magnitude of the output drive current of the second field effect transistor and controlling the brightness of the light-emitting element OLED. Due to the parasitic resistance and parasitic capacitance, the scanning selection pulse (selection signal Sn) generated by the row scanning driving circuit will be delayed. Figure 11 As shown, the accuracy of the data voltage Dm is affected, and the brightness of the light-emitting element is further affected.

[0109] In the present application, the selection signal Sn controls the switch of the first field effect transistor M1, so that the first field effect transistor M1 transmits the data voltage Dm to the first node A. Figure 10 As shown, the selection signal Sn controls the third field effect tube M3 to be turned on, and the data voltage Dm is amplified by the operational amplifier X1 and output to the Figure 6 The non-inverting input terminals of the n comparators Ui shown are Figure 4 The n comparators Ui shown compare the amplified data voltage Dm, determine the target voltage range of the amplified data voltage Dm, and according to the target voltage range, turn on the corresponding number of compensation modules 111 to amplify the current of the data voltage Dm by a corresponding number of levels and output a compensated direct current, thereby achieving a negative correlation between the current of the compensated direct current and the value in the target voltage range; the data voltage Dm and the compensated direct current are superimposed to charge the first capacitor C1, and the energy storage voltage across the first capacitor C1 controls the degree of conduction of the second field-effect transistor M2, thereby controlling the magnitude of the output drive current of the second field-effect transistor and controlling the brightness of the light-emitting element OLED.

[0110] An embodiment of the present invention further provides a display panel, which includes the above-mentioned pixel display driving circuit and a light-emitting element.

[0111] In an embodiment of the present invention, a data voltage is connected to the compensation circuit, the data voltage is compared with at least one reference voltage, and the target voltage range of the data voltage is determined based on the comparison result, and a compensated direct current is output according to the target voltage range; the pixel driving circuit responds to the connection of the selection signal and outputs a driving current based on the data voltage and the compensated direct current to illuminate the light-emitting element; the superimposed data voltage and the compensated direct current are applied to the pixel driving circuit to output the driving current, thereby enhancing the driving capability of the row scanning driving circuit and reducing the possibility of the parasitic parameter RC affecting the signal; and the current of the compensated direct current is negatively correlated with the value in the target voltage range, thereby accelerating the charging and discharging of the RC circuit while improving the accuracy of the current compensation performed by the pixel driving circuit, improving the stability of the OLED light emitting brightness, and improving the accuracy of data voltage transmission.

[0112] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0113] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A pixel display driving circuit, characterized in that: include: a compensation circuit configured to receive a data voltage, compare the data voltage with at least one reference voltage, determine a target voltage interval within which the data voltage falls based on the comparison result, and output a compensation DC current based on the target voltage interval; a pixel driving circuit connected to the compensation circuit and configured to output a driving current to the light-emitting element according to the data voltage and the compensation DC power in response to input of a selection signal, so as to light up the light-emitting element; wherein the current of the compensation direct current is negatively correlated with the value in the target voltage range; The compensation circuit includes n comparators, n-1 P-type switching tubes, n N-type switching tubes, n-1 switching elements and n compensation modules; The non-inverting input terminal of the first comparator and the first terminals of n-1 P-type switching transistors serve as the data voltage input terminal of the compensation circuit to receive the data voltage; the inverting input terminal of the i-th comparator serves as the i-th reference voltage input terminal of the compensation circuit to receive the i-th reference voltage; The output end of the (i+1)th comparator is connected to the control end of the (i+1)th P-type switching tube, the control end of the (i+1)th N-type switching tube, and the control end of the (i)th switching element; the output end of the first comparator is connected to the control end of the (1)th P-type switching tube and the control end of the (1)th N-type switching tube; The first ends of the n N-type switching tubes also serve as the data voltage input end of the compensation circuit to receive the data voltage; The second ends of the n N-type switching tubes are commonly connected to the input end of the first compensation module; The i-th switching element is connected between the i-th compensation module and the (i+1)-th compensation module; The compensation module amplifies the current of the input data voltage to output the data voltage after current amplification; Wherein, i is a positive integer less than n, and n is a positive integer.

2. The pixel display driving circuit according to claim 1, wherein: The compensation module includes an even number of cascaded inverters; the first inverter to the last inverter are connected in sequence; Wherein, the input terminal of the first inverter serves as the data voltage input terminal of the compensation module to access the data voltage; The output end of the last inverter serves as the data voltage output end after current amplification of the compensation module to output the data voltage after current amplification.

3. The pixel display driving circuit according to claim 1, wherein: The first reference voltage to the nth reference voltage decrease in sequence.

4. The pixel display driving circuit according to claim 1, wherein: n is positively correlated with the transmission distance, which is the distance between the data voltage output terminal and the pixel driving circuit.

5. The pixel display driving circuit according to claim 1, wherein: The pixel driving circuit further includes: an amplifying circuit, connected to the pixel driving circuit and the compensation circuit, and configured to amplify the data voltage to output the amplified data voltage; The compensation circuit is specifically configured to compare the amplified data voltage with at least one reference voltage, determine the target voltage interval of the data voltage according to the comparison result, and output the compensation DC power according to the target voltage interval.

6. The pixel display driving circuit according to claim 1, wherein: The pixel driving circuit includes: a first switch circuit connected to the compensation circuit and configured to transmit the data voltage in response to access of the selection signal; an energy storage circuit connected to the first switch circuit and the compensation circuit, and configured to be charged according to the data voltage, the compensation DC power, and the power supply DC power to output an energy storage voltage; The second switching circuit is connected to the first switching circuit, the energy storage circuit and the compensation circuit, and is configured to transmit the supply DC power according to the energy storage voltage to output the driving current.

7. The pixel display driving circuit according to claim 6, wherein: The first switch circuit includes a first field effect transistor, the second switch circuit includes a second field effect transistor, and the energy storage circuit includes a first capacitor.

8. The pixel display driving circuit according to any one of claims 1 to 7, wherein: The pixel driving circuit includes multiple groups of pixel driving components, and each pixel driving component includes one compensation circuit and multiple pixel driving circuits.

9. A display panel, characterized in that: The display panel includes the pixel display driving circuit and the light-emitting element according to any one of claims 1 to 8.

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