Display driving circuit and display panel

Abstract

The present application belongs to the field of display, and specifically relates to a display driving circuit and a display panel. The display driving circuit includes a driving transistor, a first light-emitting control unit, a storage unit, a data writing unit, a voltage acquisition unit and a compensation unit. The first end of the driving transistor is connected to a first power supply through a first node and a first light-emitting control unit, and the second end of the driving transistor is connected to a second power supply through a display light-emitting unit. The storage unit is connected to the first node and the control end of the driving transistor, and the storage unit is connected to a data line through a second node and a data writing unit. The voltage acquisition unit is used to obtain a reference voltage with a constant voltage. The compensation unit is connected to the second node, the first node and the voltage acquisition unit, and is used to write the reference voltage and compensate for the first power supply voltage and the threshold voltage of the driving transistor, thereby improving the display unevenness problem caused by the power supply voltage drop and the threshold voltage difference, and improving the display quality of the display panel.

Description

Technical Field

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

[0002] OLED (Organic Light-Emitting Diode) display panels have many advantages such as self-luminescence, flexibility, thin thickness, high brightness, low power consumption, fast response, and wide color gamut. They are widely used in electronic products such as televisions, mobile phones, and laptops.

[0003] Organic light-emitting diodes (OLEDs) are driven by current. The display driver circuit includes a driver transistor. The data voltage determines the degree to which the driver transistor is turned on, which in turn determines the current flowing through the OLED and, consequently, the OLED's brightness. Furthermore, the OLED current is also affected by the power supply voltage and the threshold voltage (Vth) of the driver transistor.

[0004] Different threshold voltages of different driver transistors can easily lead to uneven display. Furthermore, voltage drops in the power supply voltage during transmission through the conductive lines (especially noticeable on large-size panels) can also cause uneven display. Existing display driver circuits typically compensate for threshold voltages, but these voltage drops can still cause uneven display, affecting the display quality of the display panel. Summary of the Invention

[0005] The purpose of the present application is to provide a display driving circuit and a display panel to improve the display unevenness problem and enhance the display quality of the display panel.

[0006] To achieve the above-mentioned object, the present application provides a display driving circuit, including a driving transistor, and the display driving circuit further includes:

[0007] a first light-emitting control unit, wherein a first end of the driving transistor is connected to a first power supply via a first node and the first light-emitting control unit, and a second end of the driving transistor is connected to a second power supply via a display light-emitting unit, the first power supply voltage being greater than the second power supply voltage, and the first light-emitting control unit is configured to write the first power supply voltage in response to a first light-emitting control line signal;

[0008] a storage unit connected to the first node and the control terminal of the driving transistor;

[0009] a data writing unit, wherein the storage unit is connected to the data line via the second node and the data writing unit, and the data writing unit is used to write a data voltage in response to a scan line signal;

[0010] A voltage acquisition unit, used to obtain a constant reference voltage;

[0011] A compensation unit is connected to the second node, the first node and the voltage acquisition unit, and is at least used to write the reference voltage and compensate the first power supply voltage.

[0012] Optionally, the storage unit includes a first capacitor and a second capacitor, the first capacitor is connected to the control terminal of the driving transistor and the first node, and the second capacitor is connected to the control terminal of the driving transistor and the second node.

[0013] Optionally, the compensation unit includes a first transistor and a second transistor, the first end of the first transistor is connected to the first node, the second end of the first transistor is connected to the second node, and the control end of the first transistor is connected to the first signal line;

[0014] A first terminal of the second transistor is connected to the voltage acquisition unit, and a second terminal of the second transistor is connected to the first node.

[0015] Optionally, the first light-emitting control unit includes a third transistor, a first end of the third transistor is connected to the first power supply, a second end of the third transistor is connected to the first node, a control end of the third transistor is connected to the first light-emitting control line, one of the third transistor and the second transistor is an N-type transistor and the other is a P-type transistor, and the control end of the second transistor is connected to the first light-emitting control line.

[0016] Optionally, the compensation unit further includes a fourth transistor, a first end of the fourth transistor is connected to the control end of the driving transistor, and a second end of the fourth transistor is connected to the second end of the driving transistor.

[0017] Optionally, the fourth transistor and the first transistor are both N-type transistors or the fourth transistor and the first transistor are both P-type transistors, and the control end of the fourth transistor is connected to the first signal line.

[0018] Optionally, the voltage acquisition unit includes a resistor, a first end of the resistor is connected to a constant current source and a first end of the second transistor, and a second end of the resistor is connected to a ground end.

[0019] Optionally, the capacitance of the second capacitor is smaller than the capacitance of the first capacitor.

[0020] The present application also provides a display panel, comprising:

[0021] the display driving circuit;

[0022] The display light emitting unit is connected to the display driving circuit.

[0023] Optionally, the storage unit includes a first capacitor and a second capacitor, the first capacitor is connected to the control terminal of the driving transistor and the first node, the second capacitor is connected to the control terminal of the driving transistor and the second node, the compensation unit includes a first transistor and a second transistor, the first terminal of the first transistor is connected to the first node, the second terminal of the first transistor is connected to the second node, the control terminal of the first transistor is connected to the first signal line, the first terminal of the second transistor is connected to the voltage acquisition unit, and the second terminal of the second transistor is connected to the first node;

[0024] The first light-emitting control unit includes a third transistor, a first end of the third transistor is connected to the first power supply, a second end of the third transistor is connected to the first node, a control end of the third transistor is connected to the first light-emitting control line, the third transistor is a P-type transistor, the second transistor is an N-type transistor, the control end of the second transistor is connected to the first light-emitting control line, the first light-emitting control line in the nth row is the scan line in the n-1th row, and n is an integer greater than or equal to 2; and / or

[0025] The compensation unit also includes a fourth transistor, a first end of the fourth transistor is connected to the control end of the driving transistor, a second end of the fourth transistor is connected to the second end of the driving transistor, the fourth transistor and the first transistor are both P-type transistors, the control end of the fourth transistor is connected to the first signal line, the first signal line in the nth row is the scan line in the (n+1)th row, and n is an integer greater than or equal to 1.

[0026] The display driving circuit and display panel disclosed in this application have the following beneficial effects:

[0027] In the present application, a display driving circuit includes a driving transistor, a first light-emitting control unit, a storage unit, a data writing unit, a voltage acquisition unit, and a compensation unit. The first end of the driving transistor is connected to the first power supply through the first node and the first light-emitting control unit, and the second end of the driving transistor is connected to the second power supply through the display light-emitting unit. The storage unit is connected to the first node and the control end of the driving transistor, and the storage unit is connected to the data line through the second node and the data writing unit. The voltage acquisition unit is used to obtain a reference voltage with a constant voltage. The compensation unit is connected to the second node, the first node, and the voltage acquisition unit, and is used to write the reference voltage and compensate for the first power supply voltage and the threshold voltage of the driving transistor. That is, the current of the display light-emitting unit is independent of the first power supply voltage and the threshold voltage of the driving transistor, thereby improving the display unevenness problem caused by the power supply voltage drop and the threshold voltage difference, and improving the display quality of the display panel.

[0028] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0029] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0031] Figure 1 Schematic diagram of the structure of the display driving circuit in the first embodiment of the present application.

[0032] Figure 2 This is a timing diagram of the display driving circuit in Example 1 of the present application.

[0033] Figure 3 It is a structural diagram of the display panel in the second embodiment of the present application.

[0034] Description of reference numerals:

[0035] 11. Scan line; 12. Data line;

[0036] 100, display driver circuit; 110, driver transistor; 120, first light-emitting control unit; 121, third transistor; 130, storage unit; 131, first capacitor; 132, second capacitor; 140, data write unit; 141, fifth transistor; 150, voltage acquisition unit; 151, resistor; 160, compensation unit; 161, first transistor; 162, second transistor; 163, fourth transistor; 170, second light-emitting control unit; 171, third transistor;

[0037] 200. Display light-emitting unit. DETAILED DESCRIPTION

[0038] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0039] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0040] The present application is further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be understood as limiting the present application.

[0041] Example 1

[0042] See also Figure 1 and Figure 2 As shown, the display driving circuit in the present application includes a driving transistor 110, a first light-emitting control unit 120, a storage unit 130, a data writing unit 140, a voltage acquisition unit 150, and a compensation unit 160. The first terminal of the driving transistor 110 is connected to a first power supply via a first node A and the first light-emitting control unit 120, and the first power supply voltage is VDD. The second terminal of the driving transistor 110 is connected to a second power supply via a display light-emitting unit 200, and the second power supply voltage is VSS. The display light-emitting unit 200 includes an organic light-emitting diode. The second power supply voltage VSS can be 0, and the first power supply voltage VDD is greater than the second power supply voltage VSS. The first light-emitting control unit 120 is configured to write the first power supply voltage VDD in response to a first light-emitting control line signal EM1. The first power supply, the driving transistor 110, the display light-emitting unit 200, and the first power supply are then turned on, and the display light-emitting unit 200 emits light.

[0043] The storage unit 130 is connected to the first node A and the control terminal of the driving transistor 110. The storage unit 130 is connected to the data line 12 via the second node B and the data writing unit 140. The data writing unit 140 is used to write the data voltage Vdata in response to the scan line 11 signal Gn. The voltage acquisition unit 150 is used to obtain a constant reference voltage Vref. The storage unit 130 is used to store the data voltage Vdata, the threshold voltage Vth of the driving transistor 110, and the reference voltage Vref. The compensation unit 160 is connected to the second node B, the first node A, and the voltage acquisition unit 150, and is used to write the reference voltage Vref and compensate the first power supply voltage VDD, as well as the threshold voltage Vth of the driving transistor 110. Compensating the first power supply voltage VDD and the threshold voltage Vth of the driving transistor 110 indicates that the current Ioled of the light-emitting unit 200 is related to the reference voltage Vref and the data voltage Vdata, and is independent of the first power supply voltage VDD and the threshold voltage Vth of the driving transistor 110.

[0044] In some technical solutions, the display driving circuit compensates for the threshold voltage Vth but does not compensate for the power supply voltage. The display unevenness caused by the power supply voltage drop is not improved, which affects the display effect of the display panel.

[0045] In this embodiment, the display driving circuit includes a driving transistor 110, a first light emitting control unit 120, a storage unit 130, a data writing unit 140, a voltage acquisition unit 150, and a compensation unit 160. The first end of the driving transistor 110 is connected to the first power supply through the first node A and the first light emitting control unit 120. The second end of the driving transistor 110 is connected to the second power supply through the display light emitting unit 200. The storage unit 130 is connected to the first node A and the control end of the driving transistor 110. The storage unit 130 is connected to the data through the second node B and the data writing unit 140. Line 12 is connected, the voltage acquisition unit 150 is used to obtain a reference voltage Vref with a constant voltage, and the compensation unit 160 is connected to the second node B, the first node A and the voltage acquisition unit 150, and is used to write the reference voltage Vref and compensate the first power supply voltage VDD and the threshold voltage Vth of the driving transistor 110, that is, the current Ioled of the display light-emitting unit 200 is independent of the first power supply voltage VDD and the threshold voltage Vth of the driving transistor 110, thereby improving the display unevenness problem caused by the power supply voltage drop and the threshold voltage difference, and improving the display quality of the display panel.

[0046] See also Figure 1 and Figure 2As shown, storage unit 130 includes a first capacitor 131 and a second capacitor 132. First capacitor 131 is connected to the control terminal of driving transistor 110 and first node A, and second capacitor 132 is connected to the control terminal of driving transistor 110 and second node B. Driving transistor 110 may be a P-type thin film transistor. The first terminal, second terminal, and control terminal of driving transistor 110 are its source, drain, and gate, respectively. The data voltage Vdata is less than the reference voltage Vref.

[0047] When the display driver circuit is working:

[0048] In the compensation phase T1, the reference voltage Vref is written to the first node A, the gate voltage Vg of the driving transistor 110 is Vref+Vth, the source voltage Vs of the driving transistor 110 is Vref, the gate-source voltage difference Vgs of the driving transistor 110 is Vth, and the gate-source voltage difference Vgs of the driving transistor 110 is equal to the voltage of the first capacitor 131, that is, the first capacitor 131 stores the threshold voltage Vth of the driving transistor 110;

[0049] In the data writing phase T2, the data voltage Vdata on the data line 12 is written into the second node B. Since the capacitor voltage cannot suddenly change and the first capacitor 131 and the second capacitor 132 are connected in series, the gate voltage of the driving transistor 110 becomes Vg=Vref+Vth+((Vdata-Vref)C2 / (C1+C2)), where C1 is the capacitance of the first capacitor 131 and C2 is the capacitance of the second capacitor 132. The gate-source voltage difference Vgs of the driving transistor 110 becomes VGS=Vth+((Vdata-Vref)C2 / (C1+C2)).

[0050] In the light-emitting stage T3, the first power supply, the driving transistor 110, the display light-emitting unit 200 and the first power supply are turned on, the display light-emitting unit 200 starts to emit light, and the current flowing through the display light-emitting unit 200 is Ioled=K(Vgs-Vth)2=K((Vdata-Vref)C2 / (C1+C2))2, where K is a constant coefficient.

[0051] According to the calculation formula of the current Ioled of the display light-emitting unit 200, it can be seen that the current Ioled of the display light-emitting unit 200 is related to the reference voltage Vref and the data voltage Vdata, and is not related to the first power supply voltage VDD and the threshold voltage Vth of the driving transistor 110. That is, the first power supply voltage VDD and the threshold voltage Vth of the driving transistor 110 are compensated, thereby improving the display unevenness caused by the voltage drop of the first power supply voltage VDD and the difference in the threshold voltage Vth.

[0052] See also Figure 1 and Figure 2As shown, compensation unit 160 includes a first transistor 161 and a second transistor 162. A first terminal of first transistor 161 is connected to first node A, a second terminal of first transistor 161 is connected to second node B, and a control terminal of first transistor 161 is connected to a first signal line, where the signal of first signal line is S1. A first terminal of second transistor 162 is connected to voltage acquisition unit 150, a second terminal of second transistor 162 is connected to first node A, and a control terminal of second transistor 162 is connected to another independent signal line. First transistor 161 and second transistor 162 can both be N-type thin film transistors.

[0053] When the display driving circuit is working: in the compensation stage T1, the first signal line signal S1 and the signal line signal controlling the second transistor 162 are high-level signals, the first transistor 161 and the second transistor 162 are both turned on, the reference voltage Vref is written to the first node A, the gate voltage Vg of the driving transistor 110 is Vref+Vth, the source voltage Vs of the driving transistor 110 is Vref, and the gate-source voltage difference Vgs of the driving transistor 110 is Vth.

[0054] It should be noted that the first transistor 161 can be, but is not limited to, an N-type thin film transistor. The first transistor 161 can also be a P-type thin film transistor, depending on the specific situation. The second transistor 162 can be, but is not limited to, an N-type thin film transistor. The second transistor 162 can also be a P-type thin film transistor, depending on the specific situation.

[0055] See also Figure 1 and Figure 2 As shown, the voltage acquisition unit 150 includes a resistor 151. A first end of the resistor 151 is connected to the constant current source Idd and the first end of the second transistor 162. A second end of the resistor 151 is connected to a ground terminal, and the voltage of the ground terminal can be 0. The current of the constant current source Idd is not shunted, the resistance value of the resistor 151 is constant, and the voltage at the first end of the resistor 151 can be used as a constant voltage reference voltage Vref.

[0056] The first power supply is used to power the display light-emitting unit 200, and the reference voltage Vref is used to charge the first capacitor 131 and the second capacitor 132. The reference voltage Vref has a small load, which is conducive to stabilizing the reference voltage Vref and avoiding uneven display caused by unstable reference voltage Vref.

[0057] See also Figure 1 and Figure 2As shown, the first light-emission control unit 120 includes a third transistor 121. A first terminal of the third transistor 121 is connected to the first power supply, a second terminal of the third transistor 121 is connected to the first node A, and a control terminal of the third transistor 121 is connected to a first light-emission control line. The first light-emission control line signal is EM1. The third transistor 121 can be a P-type thin-film transistor, and the second transistor 162 can be an N-type thin-film transistor. The control terminal of the second transistor 162 is connected to the first light-emission control line. In other words, the third transistor 121 and the second transistor 162 share the first light-emission control line signal EM1 for control.

[0058] When the display driving circuit is working: in the compensation stage T1, the first signal line signal S1 and the first light-emitting control line signal EM1 are high-level signals, the first transistor 161 and the second transistor 162 are both turned on, the third transistor 121 is turned off, the reference voltage Vref is written to the first node A, the gate voltage Vg of the driving transistor 110 is Vref+Vth, the source voltage Vs of the driving transistor 110 is Vref, and the gate-source voltage difference Vgs of the driving transistor 110 is Vth.

[0059] The third transistor 121 and the second transistor 162 can share a control signal, which can reduce the number of control signals and signal line routing.

[0060] It should be noted that the third transistor 121 can be a P thin film transistor, and the second transistor 162 can be an N thin film transistor, but is not limited thereto. The third transistor 121 can be an N thin film transistor, and the second transistor 162 can be a P thin film transistor, depending on the specific situation.

[0061] See also Figure 1 and Figure 2 As shown, compensation unit 160 further includes a fourth transistor 163. A first terminal of fourth transistor 163 is connected to the control terminal of driving transistor 110, and a second terminal of fourth transistor 163 is connected to the second terminal of driving transistor 110. The control terminal of fourth transistor 163 can be connected to a second signal line and controlled by second signal line signal S2. Fourth transistor 163 is turned on during compensation phase T1 and turned off during data writing phase T2 and light emission phase T3. Fourth transistor 163 can be a P-type thin film transistor.

[0062] The fourth transistor 163 is turned on in the compensation phase T1 , and the gate and drain of the driving transistor 110 are turned on by the fourth transistor 163 , which helps to maintain the gate and source voltages of the driving transistor 110 .

[0063] It should be noted that the fourth transistor 163 may be a P-type thin film transistor, but is not limited thereto. The fourth transistor 163 may be an N-type thin film transistor, depending on the specific situation.

[0064] In some embodiments, the data write unit 140 includes a fifth transistor 141, a first terminal of the fifth transistor 141 being connected to the data line 12, a second terminal of the fifth transistor 141 being connected to the second node B, and a control terminal of the fifth transistor 141 being connected to the scan line 11. The fifth transistor 141 may be a P-type thin film transistor. The display drive circuit also includes a second light emission control unit 170, which includes a sixth transistor 171. A first terminal of the sixth transistor 171 is connected to the second terminal of the drive transistor 110, and a second terminal of the sixth transistor 171 is connected to the display light emission unit 200. The sixth transistor 171 may be a P-type thin film transistor, a control terminal of the sixth transistor 171 being connected to the second light emission control line and controlled by the second light emission control line signal EM2. It should be understood that the sixth transistor 171 may also be an N-type thin film transistor.

[0065] The third transistor 121 , the fourth transistor 163 , the fifth transistor 141 , the sixth transistor 171 and the driving transistor 110 are all P-type thin film transistors, and the first transistor 161 and the second transistor 162 are N-type thin film transistors.

[0066] When the display driver circuit is working:

[0067] In the compensation phase T1, the second signal line signal S2 and the second light-emitting control signal EM2 are low-level signals, the first signal line signal S1, the scan line 11 signal Gn, and the first light-emitting control line signal EM1 are high-level signals, the third transistor 121 and the fifth transistor 141 are turned off, the first transistor 161, the second transistor 162, the fourth transistor 163, and the sixth transistor 171 are turned on, the gate and the drain of the driving transistor 110 are short-circuited by the fourth transistor 163, the sixth transistor 171 is turned on, the residual charge of the storage unit 130 is released to the second power supply, the first transistor 161 and the second transistor 162 are turned on, the reference voltage Vref is written to the first node A, the gate voltage Vg of the driving transistor 110 is Vref+Vth, the source voltage Vs of the driving transistor 110 is Vref, the gate-source voltage difference Vgs of the driving transistor 110 is Vth, and the gate-source voltage difference Vgs of the driving transistor 110 is equal to the voltage of the first capacitor 131, that is, the first capacitor 131 stores the threshold voltage Vth of the driving transistor 110;

[0068] In the data writing phase T2, the first signal line signal S1 and the scan line 11 signal Gn are low-level signals, the second signal line signal S2, the first light-emitting control line signal EM1 and the second light-emitting control signal EM2 are high-level signals, the second transistor 162 and the fifth transistor 141 are turned on, the first transistor 161, the third transistor 121, the fourth transistor 163 and the sixth transistor 171 are turned off, and the data voltage Vdata on the data line 12 is written into the second node B. Since the voltages of the first capacitor 131 and the second capacitor 132 cannot change suddenly and the first capacitor 131 and the second capacitor 132 are connected in series, the gate voltage Vg of the driving transistor 110 becomes Vg=Vref+Vth+((Vdata-Vref)C2 / (C1+C2)), and the gate-source voltage difference Vgs of the driving transistor 110 is Vth+((Vdata-Vref)C2 / (C1+C2));

[0069] In the light-emitting stage T3, the first signal line signal S1, the first light-emitting control line signal EM1 and the second light-emitting control signal EM2 are low-level signals, the second signal line signal S2 and the scan line 11 signal Gn are high-level signals, the first transistor 161, the second transistor 162, the fourth transistor 163 and the fifth transistor 141 are turned off, the third transistor 121, the sixth transistor 171 and the driving transistor 110 are turned on, the first power supply, the driving transistor 110, the display light-emitting unit 200 and the first power supply are turned on, and the display light-emitting unit 200 starts to emit light.

[0070] In some embodiments, the capacitance of the second capacitor 132 is smaller than the capacitance of the first capacitor 131 .

[0071] The second capacitor 132 is used to maintain the driving transistor 110 turned on. The capacitance of the second capacitor 132 is relatively larger, which can make the display light-emitting unit 200 emit light stably in the light-emitting stage T3; the first capacitor 131 is used to balance the voltage of the first capacitor 131. The capacitance of the second capacitor 132 is relatively smaller, which can make the second capacitor 132 charge faster and consume less power.

[0072] In some embodiments, the first transistor 161 and the fourth transistor 163 are both P-type transistors, and the control terminal of the fourth transistor 163 is connected to the first signal line. That is, the first transistor 161 and the fourth transistor 163 share the first signal line signal S1 for control. The timing of the first signal line signal S1 adopts the timing of the second signal line signal S2.

[0073] The first transistor 161 and the fourth transistor 163 share a control signal, which can reduce the number of control signals and signal line routing.

[0074] It should be noted that the first transistor 161 and the fourth transistor 163 are both P-type transistors, but are not limited thereto. The first transistor 161 and the fourth transistor 163 may also be both N-type transistors, depending on the specific situation. The fourth transistor 163 and the first transistor 161 are both N-type transistors, and the first transistor 161 and the fourth transistor 163 share the first signal line signal S1 for control.

[0075] In some embodiments, the sixth transistor 171 may be an N-type thin film transistor. The control terminal of the sixth transistor 171 is connected to the scan line 11 and is controlled by the scan line 11 signal Gn. That is, the sixth transistor 171 and the fifth transistor 141 share the scan line 11 signal Gn for control.

[0076] The sixth transistor 171 and the fifth transistor 141 share a control signal, which can reduce the number of control signals and signal line routing.

[0077] In some embodiments, the first transistor 161, the second transistor 162, the third transistor 121, the fourth transistor 163, the fifth transistor 141, the sixth transistor 171, and the driving transistor 110 may all be P-type thin film transistors, that is, all transistors in the display driving circuit are P-type thin film transistors. When all transistors in the display driving circuit are P-type thin film transistors, the control terminal of the second transistor 162 is connected to the third signal line and is controlled by the third signal line S3, and the control terminal of the third transistor 121 is connected to the first light emission control line and is controlled by the first light emission control line signal EM1.

[0078] All transistors in the display driving circuit are P-type thin film transistors, which can reduce the manufacturing cost of the display driving circuit.

[0079] It should be noted that the first transistor 161, the second transistor 162, the third transistor 121, the fourth transistor 163, the fifth transistor 141, the sixth transistor 171 and the driving transistor 110 can all be P-type thin film transistors, that is, all transistors in the display driving circuit are P-type thin film transistors, but are not limited to this. All transistors in the display driving circuit can also be N-type thin film transistors, depending on the specific situation.

[0080] Example 2

[0081] See also Figure 3 As shown, the display panel in this embodiment includes a display driving circuit 100 and a display light emitting unit 200 . The display light emitting unit 200 is connected to the display driving circuit 100 . The display driving circuit 100 includes the display driving circuit 100 disclosed in the first embodiment.

[0082] The display panel includes a display driving circuit 100, which includes a driving transistor 110, a first light emitting control unit 120, a storage unit 130, a data writing unit 140, a voltage acquiring unit 150, and a compensation unit 160. The first end of the driving transistor 110 is connected to the first power supply through the first node A and the first light emitting control unit 120, the second end of the driving transistor 110 is connected to the second power supply through the display light emitting unit 200, the storage unit 130 is connected to the first node A and the control end of the driving transistor 110, and the storage unit 130 is connected to the data writing unit 140 through the second node B. 0 is connected to the data line 12, the voltage acquisition unit 150 is used to obtain a reference voltage Vref with a constant voltage, and the compensation unit 160 is connected to the second node B, the first node A and the voltage acquisition unit 150, and is used to write the reference voltage Vref and compensate the first power supply voltage VDD and the threshold voltage Vth of the driving transistor 110. Through compensation, the influence of the first power supply voltage VDD and the threshold voltage Vth of the driving transistor 110 on the current flowing through the display light-emitting unit 200 is eliminated, the display unevenness problem caused by the power supply voltage drop and the threshold voltage difference is improved, and the display quality of the display panel is improved.

[0083] In some embodiments, the display panel includes multiple rows of scan lines 11 and multiple rows of data lines 12 arranged in an array. The display driver circuit 100 corresponds to the intersection of the scan lines 11 and the data lines 12, and the display driver circuit 100 is connected to the scan lines 11 in the row and the data lines 12 in the column. The display light-emitting unit 200 is connected to the display driver circuit 100 in a one-to-one correspondence. The duration of the compensation phase T1, the data writing phase T2, and the light-emitting phase T3 can be set to 1H (1H = (1 / Freq-t) / m, where Freq is the frequency, t is the frame blanking period, and m is the number of scan lines 11).

[0084] The third transistor 121 is a P-type transistor, and the second transistor 162 is an N-type transistor. The control terminals of the third transistor 121 and the second transistor 162 are both connected to the first light-emitting control line and controlled by the first light-emitting control line signal EM1. Since the first light-emitting control line signal EM1 is 1H later than the scanning line 11 signal Gn, as shown in FIG. Figure 2 As shown, the first light emitting control line of the nth row can be the scan line 11 of the n-1th row, where n is an integer greater than or equal to 2. The fourth transistor 163 and the first transistor 161 are both P-type transistors. The control end of the fourth transistor 163 and the control end of the first transistor 161 are both connected to the first signal line and controlled by the first signal line signal S1. Since the first light emitting control line signal S1 is 1H earlier than the scan line 11 signal Gn, as shown in FIG. Figure 2 As shown, the first signal line in the nth row may be the scan line 11 in the (n+1)th row, where n is an integer greater than or equal to 1.

[0085] The first light emitting control line in the nth row can be the scan line 11 in the n-1th row, and the first signal line in the nth row can be the scan line 11 in the n+1th row. This design can reduce the number of control signals and signal line routing.

[0086] The terms "first," "second," etc., 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 identified with "first," "second," etc., may explicitly or implicitly include one or more of such features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0087] In this application, unless otherwise specified or limited, terms such as "assembly" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0088] In the description of this specification, the reference terms "some embodiments", "exemplarily", etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0089] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application. Therefore, any changes or modifications made in accordance with the claims and description of the present application should fall within the scope of the patent application.

Claims

1. A display driving circuit, comprising a driving transistor, characterized in that: The display driving circuit further includes: a first light-emitting control unit, wherein a first end of the driving transistor is connected to a first power supply via a first node and the first light-emitting control unit, and a second end of the driving transistor is connected to a second power supply via a display light-emitting unit, the first power supply voltage being greater than the second power supply voltage, and the first light-emitting control unit is configured to write the first power supply voltage in response to a first light-emitting control line signal; a storage unit connected to the first node and the control terminal of the driving transistor; a data writing unit, wherein the storage unit is connected to the data line via the second node and the data writing unit, and the data writing unit is used to write a data voltage in response to a scan line signal; A voltage acquisition unit, used to obtain a constant reference voltage; a compensation unit, connected to the second node, the first node, and the voltage acquisition unit, and at least configured to write the reference voltage and compensate for the first power supply voltage; The storage unit includes a first capacitor and a second capacitor, the first capacitor is connected to the control terminal of the driving transistor and the first node, and the second capacitor is connected to the control terminal of the driving transistor and the second node; The compensation unit includes a first transistor and a second transistor, wherein the first terminal of the first transistor is connected to the first node, the second terminal of the first transistor is connected to the second node, and the control terminal of the first transistor is connected to the first signal line; A first terminal of the second transistor is connected to the voltage acquisition unit, and a second terminal of the second transistor is connected to the first node.

2. The display driving circuit according to claim 1, wherein: The first light-emitting control unit includes a third transistor, a first end of the third transistor is connected to the first power supply, a second end of the third transistor is connected to the first node, a control end of the third transistor is connected to the first light-emitting control line, one of the third transistor and the second transistor is an N-type transistor and the other is a P-type transistor, and the control end of the second transistor is connected to the first light-emitting control line.

3. The display driving circuit according to claim 1, wherein: The compensation unit further includes a fourth transistor, a first terminal of the fourth transistor is connected to the control terminal of the driving transistor, and a second terminal of the fourth transistor is connected to the second terminal of the driving transistor.

4. The display driving circuit according to claim 3, wherein: The fourth transistor and the first transistor are both N-type transistors or the fourth transistor and the first transistor are both P-type transistors, and the control end of the fourth transistor is connected to the first signal line.

5. The display driving circuit according to claim 1, wherein: The voltage acquisition unit includes a resistor, a first end of the resistor is connected to a constant current source and a first end of the second transistor, and a second end of the resistor is connected to a ground end.

6. The display driving circuit according to claim 1, wherein: The capacitance of the second capacitor is smaller than the capacitance of the first capacitor.

7. A display panel, characterized in that: include: The display driving circuit according to any one of claims 1 to 6; The display light emitting unit is connected to the display driving circuit.

8. The display panel according to claim 7, wherein: The storage unit includes a first capacitor and a second capacitor, the first capacitor is connected to the control terminal of the driving transistor and the first node, the second capacitor is connected to the control terminal of the driving transistor and the second node, the compensation unit includes a first transistor and a second transistor, the first terminal of the first transistor is connected to the first node, the second terminal of the first transistor is connected to the second node, the control terminal of the first transistor is connected to the first signal line, the first terminal of the second transistor is connected to the voltage acquisition unit, and the second terminal of the second transistor is connected to the first node; The first light-emitting control unit includes a third transistor, a first end of the third transistor is connected to the first power supply, a second end of the third transistor is connected to the first node, a control end of the third transistor is connected to the first light-emitting control line, the third transistor is a P-type transistor, the second transistor is an N-type transistor, the control end of the second transistor is connected to the first light-emitting control line, the first light-emitting control line in the nth row is the scan line in the n-1th row, and n is an integer greater than or equal to 2; and / or The compensation unit also includes a fourth transistor, a first end of the fourth transistor is connected to the control end of the driving transistor, a second end of the fourth transistor is connected to the second end of the driving transistor, the fourth transistor and the first transistor are both P-type transistors, the control end of the fourth transistor is connected to the first signal line, the first signal line in the nth row is the scan line in the (n+1)th row, and n is an integer greater than or equal to 1.

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