Pixel circuit, display panel and display device

Abstract

The invention discloses a pixel circuit, a display panel and a display device. The pixel circuit comprises a light-emitting element, a PAM module, a PWM module and an auxiliary module. The PAM module includes: a first driving unit providing a first driving signal to the light emitting element; a first writing unit that writes a first data signal; a storage unit storing the first data signal; a light emission control unit that controls a transmission path of the first driving signal; the PWM module comprises a second driving unit which provides a second driving signal for the first driving unit; a second writing unit that writes a second data signal; the coupling unit is used for coupling the modulation signal to the second driving unit; a drive control unit that controls a transmission path of the second drive signal; the auxiliary module is used for resetting the light-emitting element; a working period of the auxiliary module overlaps a working stage of at least one of the light emission control unit, the driving control unit, and the modulation signal. By adopting the technical scheme, the light-emitting duration can be accurately controlled.

Description

Technical Field

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

[0002] A light emitting diode (LED) display panel is a flat panel display panel that includes multiple LEDs. Compared to a liquid crystal display (LCD) panel that requires a backlight, an LED display panel can provide better contrast, response time, and energy efficiency.

[0003] When LED receives a lower driving current, the luminous efficiency is low and the low grayscale is difficult to distinguish. In order to improve the display effect of the LED display panel, a driving method combining pulse width modulation (PWM) and pulse amplitude modulation (PAM) can be used.

[0004] However, when the control voltage of the PWM module is transmitted to pixel circuits at different positions in the display panel, the voltage signal is easily distorted due to the voltage drop, resulting in some pixel circuits being unable to accurately control the light emission duration of the LED, affecting the display effect. Summary of the invention

[0005] The present invention provides a pixel circuit, a display panel and a display device, so that the pixel circuit can accurately control the light-emitting duration of an LED and improve the display effect.

[0006] According to one aspect of the present invention, there is provided a pixel circuit, comprising: a light emitting element, a pulse amplitude modulation module, a pulse width modulation module and an auxiliary module;

[0007] The pulse amplitude modulation module includes a first driving unit, a first writing unit, a storage unit and a light-emitting control unit; the first driving unit is used to provide a first driving signal to the light-emitting element; the first writing unit is used to write a first data signal to the first driving unit; the storage unit is used to store the first data signal to the first driving unit; the light-emitting control unit is used to control the transmission path of the first driving signal provided by the first driving unit to the light-emitting element;

[0008] The pulse width modulation module includes a second driving unit, a second writing unit, a driving control unit and a coupling unit; the second driving unit is used to provide a second driving signal to the first driving unit; the second writing unit is used to write a second data signal to the second driving unit; the coupling unit is used to couple the variation of the modulation signal to the second driving unit; the driving control unit is used to control the transmission path of the second driving signal provided by the second driving unit to the first driving unit;

[0009] The auxiliary module is used to reset the light emitting element; wherein the working period of the auxiliary module overlaps with at least one of the working period of the light emitting control unit, the working period of the driving control unit and the modulation phase of the modulation signal.

[0010] According to yet another aspect of the present invention, a display panel is provided, comprising the above pixel circuit.

[0011] According to yet another aspect of the present invention, a display device is provided, comprising the above-mentioned display panel.

[0012] The technical solution of the present invention, by setting an auxiliary module, and overlapping with at least one of the working period of the light-emitting control unit, the working period of the driving control unit and the modulation stage of the modulation signal, enables the auxiliary module to reset the light-emitting element when the second driving unit is turned on, control the light-emitting element to stop emitting light, and the light-emitting element can enter the black state in time during the driving stage, so that the signal received by the pulse width modulation module of the pixel circuit far from the display chip can be avoided from being distorted, resulting in the failure to control the first driving unit to turn off when the second driving unit is turned on, causing the light-emitting element that should have stopped emitting light to continue emitting light and fail to enter the black state in time, affecting the pulse width of the first driving signal, and further affecting the display grayscale, causing display abnormality. Using the solution of the present invention, whether it is a pixel circuit close to the display chip or a pixel circuit far away, the light-emitting duration of the light-emitting element can be accurately controlled to achieve precise control of the display grayscale and improve the display effect.

[0013] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions 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 creative work.

[0015] Figure 1 is a circuit structure schematic diagram of a pixel circuit provided by an embodiment of the present invention;

[0016] Figure 2 is a circuit structure schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0017] Figure 3 is a timing diagram of a pixel circuit provided by an embodiment of the present invention;

[0018] Figure 4 is a circuit structure schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0019] Figure 5 is a timing diagram of another pixel circuit provided by an embodiment of the present invention;

[0020] Figure 6 is a circuit structure schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0021] Figure 7 is a timing diagram of another pixel circuit provided by an embodiment of the present invention;

[0022] Figure 8 is a circuit structure schematic diagram of another pixel circuit provided by an embodiment of the present invention;

[0023] Fig. 9 is a timing diagram of another pixel circuit provided by an embodiment of the present invention;

[0024] Fig.10 is a timing diagram of another pixel circuit provided by an embodiment of the present invention;

[0025] Fig.11 is a timing diagram of another pixel circuit provided by an embodiment of the present invention;

[0026] Fig.12 is a timing diagram of another pixel circuit provided by an embodiment of the present invention;

[0027] Fig.13 is a timing diagram of another pixel circuit provided by an embodiment of the present invention;

[0028] Fig.14 is a timing diagram of another pixel circuit provided by an embodiment of the present invention;

[0029] Fig.15 is a schematic diagram of a top view structure of a display panel provided by an embodiment of the present invention;

[0030] Fig.16 It is a structural schematic diagram of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0032] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0033] As mentioned in the background technology, the existing LED display panel includes multiple pixel circuits. In order to improve the display effect, a PWM module is usually used to control the duration of the PAM module providing a driving signal to the LED, so that the multiple LEDs can display multiple grayscales within one frame display time, especially multiple grayscales within the low grayscale range within one frame display time. However, due to the influence of the signal line voltage drop, the voltage signal received by the PWM module of the pixel circuit far away from the display chip will be distorted, affecting the control signal provided by the PWM module to the PAM module, and further affecting the duration of the PAM module providing the driving signal to the LED, causing the LED to be unable to emit light accurately and unable to accurately enter the black state, affecting the display effect.

[0034] To solve the above technical problems, an embodiment of the present invention provides a pixel circuit, comprising: a light-emitting element, a pulse amplitude modulation module, a pulse width modulation module and an auxiliary module; the pulse amplitude modulation module comprises a first driving unit, a first writing unit, a storage unit and a light-emitting control unit; the first driving unit is used to provide a first driving signal to the light-emitting element; the first writing unit is used to write a first data signal to the first driving unit; the storage unit is used to store the first data signal to the first driving unit; the light-emitting control unit is used to control the transmission path of the first driving unit providing the first driving signal to the light-emitting element; the pulse width modulation module comprises a second driving unit, a second writing unit, a driving control unit and a coupling unit; the second driving unit is used to provide a second driving signal to the first driving unit; the second writing unit is used to write a second data signal to the second driving unit; the coupling unit is used to couple the change amount of the modulation signal to the second driving unit; the driving control unit is used to control the transmission path of the second driving unit providing the second driving signal to the first driving unit; the auxiliary module is used to reset the light-emitting element; wherein the working period of the auxiliary module overlaps with at least one of the working period of the light-emitting control unit, the working period of the driving control unit and the modulation phase of the modulation signal.

[0035] By adopting the above technical solution, by setting an auxiliary module, and overlapping with at least one of the working period of the light-emitting control unit, the working period of the driving control unit and the modulation stage of the modulation signal, the auxiliary module can reset the light-emitting element when the second driving unit is turned on, control the light-emitting element to stop emitting light, and the light-emitting element can enter the black state in time during the driving stage. In this way, it can be avoided that the pulse width modulation module of the pixel circuit far away from the display chip receives a signal distortion, resulting in the failure to control the first driving unit to turn off when the second driving unit is turned on, causing the light-emitting element that should have stopped emitting light to continue to emit light and fail to enter the black state in time, affecting the pulse width of the first driving signal, and then affecting the display grayscale, causing display abnormality. By adopting the solution of the present invention, whether it is a pixel circuit close to the display chip or a pixel circuit far away, the light-emitting duration of the light-emitting element can be accurately controlled to achieve precise control of the display grayscale and improve the display effect.

[0036] The above is the core idea of ​​the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention.

[0037] Figure 1 is a circuit structure diagram of a pixel circuit provided by an embodiment of the present invention, with reference to Figure 1The pixel circuit includes: a light emitting element LED, a pulse amplitude modulation (PAM) module 100, a pulse width modulation (PWM) module 200 and an auxiliary module 300.

[0038] The PAM module 100 includes a first driving unit 110, a first writing unit 120, a storage unit 130 and a light-emitting control unit 140. The first driving unit 110 is used to provide a first driving signal to the light-emitting element LED, the first writing unit 120 is used to write a first data signal Data1 to the first driving unit 110, the storage unit 130 is used to store the first data signal Data1 to the first driving unit 110, and the light-emitting control unit 140 is used to control the transmission path of the first driving unit 110 to provide the first driving signal to the light-emitting element LED.

[0039] The PWM module 200 includes a second drive unit 210, a second write unit 220, a coupling unit 230 and a drive control unit 240. The second drive unit 210 is used to provide a second drive signal to the first drive unit 110. The second write unit 220 is used to write a second data signal Data2 to the second drive unit 210. The coupling unit 230 is used to couple the change amount of the modulation signal Sweep to the second drive unit 210. The drive control unit 240 is used to control the transmission path of the second drive unit 210 to provide the second drive signal to the first drive unit 110.

[0040] The auxiliary module 300 is used to reset the light emitting element LED, wherein the working period of the auxiliary module 300 overlaps with at least one of the working period of the light emitting control unit 140 , the working period of the driving control unit 240 , and the modulation phase of the modulation signal Sweep.

[0041] For example, continue to refer to Figure 1 , the first end of the first driving unit 110 receives the first power signal VDD1, the second end of the first driving unit 110 is electrically connected to the light-emitting control unit 140, and the control end of the first driving unit 110 is electrically connected to the second end of the first writing unit 120 at the first node N1; the first end of the first writing unit 120 receives the first data signal Data1, and the control end of the first writing unit 120 receives the first writing control signal Scan12; one end of the storage unit 130 is electrically connected to the first node N1, and the other end receives the first power signal VDD1; the control end of the light-emitting control unit 140 can receive the light-emitting control signal Emit1, the second end of the light-emitting control unit 140 is electrically connected to the first pole of the light-emitting element LED, and the second pole of the light-emitting element LED receives the second power signal PVEE.

[0042] The first end of the second driving unit 210 receives the third power supply signal VDD2, the second end is electrically connected to the driving control unit 240, and the control end is electrically connected to the second end of the second writing unit 220 at the second node N2; the first end of the second writing unit 220 receives the second data signal Data2, and the control end of the second writing unit 220 receives the second writing control signal Scan22; one end of the coupling unit 230 is electrically connected to the second node N2, and the other end receives the modulation signal Sweep; the control end of the driving control unit 240 can receive the driving control signal Emit2, and the second end of the driving control unit 240 is electrically connected to the first node N1.

[0043] The first end of the auxiliary module 300 receives the auxiliary reset signal RST, the second end of the auxiliary module 300 is electrically connected to the first pole of the light-emitting element LED, and the control end of the auxiliary module 300 receives the auxiliary control signal Scan3. In an optional embodiment, the first pole of the light-emitting element LED is the anode of the light-emitting element LED, and at this time, the voltage of the auxiliary reset signal RST may be less than or equal to the voltage of the second power signal PVEE; in another optional embodiment, the first pole of the light-emitting element LED is the cathode of the light-emitting element LED, and at this time, the voltage of the auxiliary reset signal RST may be greater than or equal to the voltage of the second power signal PVEE, and when the voltage of the auxiliary reset signal RST is equal to the voltage of the second power signal PVEE, the auxiliary reset signal RST may reuse the second power signal PVEE.

[0044] In other optional embodiments, Figure 2 is a circuit structure diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 2The PAM module 100 may further include a first compensation unit 150, a first end of the first compensation unit 150 may be electrically connected to the second end of the first driving unit 110, and a second end of the first compensation unit 150 and a control end of the first driving unit 110 are electrically connected to a first node N1. At this time, a second end of the first writing unit 120 is electrically connected to a first end of the first driving unit 110; in at least part of the time period, the first compensation unit 150 and the first writing unit 120 work simultaneously. In one embodiment, the control end of the first compensation unit 150 may receive a first writing control signal Scan12. And / or, the PWM module 200 may further include a second compensation unit 250, the first end of the second compensation unit 250 may be electrically connected to the second end of the second driving unit 210, the second end of the second compensation unit 250 and the control end of the second driving unit 210 are electrically connected to the second node N2, at which time, the second end of the second writing unit 220 is electrically connected to the first end of the second driving unit 210; in at least part of the time period, the second compensation unit 250 and the second writing unit 220 work simultaneously, and in one embodiment, the control end of the second compensation unit 250 may receive a second writing control signal Scan22.

[0045] Taking the case where the effective levels of all control signals are low as an example, Figure 3 is a timing diagram of a pixel circuit provided by an embodiment of the present invention, with reference to Figure 3 The driving cycle of the pixel circuit includes a writing phase TS and a driving phase TD. It should be noted that the effective level of the control signal can be a high level or a low level, which is not limited in the embodiment of the present invention. For ease of description, the embodiment of the present invention takes the effective level of the control signal as a low level as an example to exemplify the technical solution of the embodiment of the present invention.

[0046] The writing phase TS includes a working period t12 of the first writing unit 120 and a working period t22 of the second writing unit 220. During the working period t12 of the first writing unit 120, the first writing unit 120 can write the first data signal Data1 to the first node N1; during the working period t22 of the second writing unit 220, the second writing unit 220 can write the second data signal Data2 to the second node N2. During the writing phase TS, the storage unit 130 can store the first data signal Data1 written to the first node N1, and the coupling unit 230 can store the second data signal Data2 written to the second node N2.

[0047] The driving phase TD includes the working period t3 of the auxiliary module 300, the working period te1 of the light emitting control unit 140, the working period te2 of the driving control unit 240, and the modulation phase tm of the modulation signal Sweep. During the working period t3 of the auxiliary module 300, the auxiliary module 300 can transmit the auxiliary reset signal RST to the first pole of the light emitting element LED to reset the light emitting element LED and put the light emitting element LED into a black state.

[0048] During the working period te1 of the light-emitting control unit 140, the light-emitting control unit 140 can control the first driving unit 110 to provide a transmission path for the first driving signal to the light-emitting element LED to be turned on; during at least part of the working period te1 of the light-emitting control unit 140, the first driving unit 110 can form a driving current of corresponding size according to the first data signal Data1, and provide it to the light-emitting element LED, so that the light-emitting element LED can emit light of corresponding brightness according to the first data signal Data1.

[0049] During the working period te2 of the driving control unit 240, the driving control unit 240 can control the transmission path of the second driving unit 210 to provide the second driving signal to the first driving unit 110 to be turned on. During the modulation phase tm of the modulation signal Sweep, the modulation signal Sweep changes, and the coupling unit 230 also couples the change amount of the modulation signal Sweep to the second node N2. According to the second data signal Data2 written to the second node N2 and the change amount of the modulation signal Sweep coupled to the second node N2, the working state of the second driving unit 210 can be controlled. During at least part of the working period te2 of the driving control unit 240, the second driving unit 210 is turned on, and the third power supply signal VDD2 can be provided to the first node N1, so that the first driving unit 110 stops providing the driving current to the light-emitting element LED, and the light-emitting element LED enters the black state.

[0050] It can be seen from the above description that, in addition to the control signal, the PAM module 100 can receive the first data signal Data1 and the first power signal VDD1, and control the amplitude of the driving current provided to the light-emitting element LED according to the first data signal Data1 and the first power signal VDD1; in addition to the control signal, the PWM module 200 can receive the second data signal Data2, the modulation signal Sweep and the third power signal VDD2, and control the time when the third power signal VDD2 is provided to the PAM module 100 according to the second data signal Data2 and the modulation signal Sweep, thereby controlling the pulse width of the driving current provided by the PAM module 100 to the light-emitting element LED.

[0051] By determining the amplitude and pulse width of the driving current, the display grayscale of the light-emitting element LED can be determined. Affected by the voltage drop of the signal line, one or more of the second data signal Data2, the modulation signal Sweep and the third power supply signal VDD2 received by the PWM module 200 may have signal distortion, which affects the pulse width of the driving current provided by the PAM module 100 to the light-emitting element LED; however, when the pulse width of the driving current is inaccurate due to signal distortion, the auxiliary module 300 can ensure that the light-emitting element LED can still enter the black state in time, ensuring that the light-emitting element LED can be displayed with accurate grayscale, thereby improving the display effect.

[0052] In the embodiment of the present invention, an auxiliary module is provided, and overlapped with at least one of the working period of the light-emitting control unit, the working period of the driving control unit, and the modulation stage of the modulation signal, so that the auxiliary module can reset the light-emitting element when the second driving unit is turned on, control the light-emitting element to stop emitting light, and the light-emitting element can enter the black state in time during the driving stage. In this way, it can be avoided that the signal received by the pulse width modulation module of the pixel circuit far away from the display chip is distorted, resulting in the failure to control the first driving unit to turn off when the second driving unit is turned on, causing the light-emitting element that should have stopped emitting light to continue to emit light and fail to enter the black state in time, affecting the pulse width of the first driving signal, and further affecting the display grayscale, causing display abnormality. By adopting the scheme of the present invention, whether it is a pixel circuit close to the display chip or a pixel circuit far away, the light-emitting duration of the light-emitting element can be accurately controlled to achieve accurate control of the display grayscale and improve the display effect.

[0053] Optional, Figure 4 is a circuit structure diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 4 The PAM module 100 also includes a reset unit 160, which is also used to reset the , wherein at least part of the working period of the reset unit 160 does not overlap with the working period of the light emitting control unit 140, the working period of the driving control unit 240 and the modulation phase of the modulation signal Sweep.

[0054] For example, continue to refer to Figure 4 The first end of the reset unit 160 receives the reset signal Vref3, the second end of the reset unit 160 is electrically connected to the first electrode of the light emitting element LED, and the control end of the reset unit 160 receives the reset control signal Scan1.

[0055] Taking the case where the effective levels of all control signals are low as an example, Figure 5 is a timing diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 5The driving cycle of the pixel circuit also includes a reset phase TR, and the reset phase TR includes a working period t1 of the reset unit 160, and at least a part of the working period t1 of the reset unit 160 is located before and / or after the driving phase TD. In the working period t1 of the reset unit 160, the reset unit 160 can transmit the reset signal Vref3 to the first electrode of the light-emitting element LED to reset the light-emitting element LED to clear the electrical signal of the light-emitting element LED in the current driving cycle or the previous driving cycle, which is conducive to improving the accuracy of the light-emitting brightness of the light-emitting element LED.

[0056] In an optional embodiment, the first pole of the light-emitting element LED is the anode of the light-emitting element LED. At this time, the voltage of the reset signal Vref3 can be less than the voltage of the second power signal PVEE, which is conducive to clearing the electrical signal of the anode of the light-emitting element LED. In another optional embodiment, the first pole of the light-emitting element LED is the cathode of the light-emitting element LED. At this time, the voltage of the reset signal Vref3 can be greater than the voltage of the second power signal PVEE, which is conducive to clearing the electrical signal of the anode of the light-emitting element LED. In a feasible embodiment, the reset signal Vref3 can reuse the auxiliary reset signal RST received by the auxiliary module 300.

[0057] Optional, continue to refer to Figure 4 and Figure 5 The PAM module 100 further includes a first initialization unit 170, which is used to initialize the first driving unit 110; and / or the PWM module 200 further includes a second initialization unit 270, which is used to initialize the second driving unit 210. The working period t1 of the reset unit 160 is the same as the working period of the first initialization unit 170 and / or the second initialization unit 270, and the working period t1 of the reset unit 160 does not overlap with the working period t3 of the auxiliary module 300.

[0058] For example, continue to refer to Figure 4, the first end of the first initialization unit 170 receives the first initialization signal Vref1, the second end of the first initialization unit 170 is electrically connected to the control end of the first driving unit 110 at the first node N1, and the control end of the first initialization unit 170 receives the reset control signal Scan1; and / or, the first end of the second initialization unit 270 receives the second initialization signal Vref2, the second end of the second initialization unit 270 is electrically connected to the control end of the second driving unit 210 at the second node N2, and the control end of the second initialization unit 270 also receives the reset control signal Scan1. The driving cycle of the pixel circuit also includes an initialization phase TI, and the initialization phase TI includes a working period of the first initialization unit 170 and / or the second initialization unit 270. When the control end of the first initialization unit 170 and / or the second initialization unit 270 receives the reset control signal Scan1 as the control end of the reset unit 160, the initialization phase TI overlaps at least partially with the reset phase TR, and the working period of the first initialization unit 170 and / or the second initialization unit 270 is the same as the working period t1 of the reset unit 160.

[0059] Taking the case where the control ends of the first initialization unit 170 and / or the second initialization unit 270 both receive the reset control signal Scan1 as an example, at least part of the working period t1 of the reset unit 160 is located before the writing stage TS. Before the writing stage TS, the first initialization unit 170 can transmit the first initialization signal Vref1 to the first node N1 to initialize the control end of the first driving unit 110 to clear the electrical signal of the control end of the first driving unit 110 in the previous driving cycle, so that the first driving unit 110 reaches an initial state, so as to facilitate the writing of the first data signal Data1 in the next stage; and / or, before the writing stage TS, the second initialization unit 270 can transmit the second initialization signal Vref2 to the second node N2 to initialize the control end of the second driving unit 210 to clear the electrical signal of the control end of the second driving unit 210 in the previous driving cycle, so that the second driving unit 210 reaches an initial state, so as to facilitate the writing of the second data signal Data2 in the next stage.

[0060] In other optional implementations, the control end of the first initialization unit 170 and / or the second initialization unit 270 may also receive an initialization control signal (not shown in the figure), and the working period of the first initialization unit 170 and / or the second initialization unit 270 may not overlap with the working period t1 of the reset unit 160. In this case, the initialization stage TI and the reset stage TR of the pixel circuit may not overlap; in the same driving cycle, the initialization stage TI is located before the writing stage TS, and in the initialization stage TI, the initialization control signal jumps to a valid level, and the control end of the first driving unit 110 and / or the second initialization unit 270 is initialized. Among them, when the working period t1 of the reset unit 160 does not overlap with the initialization stage TI, the working period t1 of the reset unit 160 may not be located before the writing stage TS.

[0061] In an optional embodiment, continue to refer to Figure 4 The PAM module 100 includes at least seven transistors and one capacitor (M1, M2, M3, M4, M5, M6, M7, C1), the PWM module includes at least six transistors and one capacitor (M8, M9, M10, M11, M12, M13, C2), and the auxiliary module 300 includes at least one transistor (M14).

[0062] In an optional embodiment, the first driving unit 110 includes a first driving transistor M3, the first initialization signal Vref1 can control the first driving transistor M3 to be turned on, and the absolute value of the first initialization signal Vref1 is greater than the absolute value of the threshold voltage of the first driving transistor M3; in another optional embodiment, the second driving unit 210 includes a second driving transistor M10, the second initialization signal Vref2 can control the second driving transistor M10 to be turned on, and the absolute value of the second initialization signal Vref2 is greater than the absolute value of the threshold voltage of the second driving transistor M10. In a feasible embodiment, the first initialization signal Vref1 can reuse the reset signal Vref3 received by the reset module 160 and / or the auxiliary reset signal RST received by the auxiliary module 300, and the second initialization signal Vref2 can reuse the reset signal Vref3 received by the reset module 160 and / or the auxiliary reset signal RST received by the auxiliary module 300.

[0063] Based on the above embodiments, continue to refer to Figure 4 and Figure 5 The auxiliary module 300 and the reset unit 160 are two independent structures. For example, the auxiliary module 300 may include an auxiliary transistor M14, and the reset unit 160 may include a reset transistor M7; the working period t1 of the reset module 160 and the working period t3 of the auxiliary module 300 do not overlap.

[0064] Exemplarily, the working period t1 of the reset unit 160 is located before the driving stage TD, and the working period t3 of the auxiliary module 300 is located in the driving stage TD. The driving cycle of the pixel circuit only includes the working period t1 of the reset unit 160, and the driving cycle of the pixel circuit also only includes the working period t3 of the auxiliary module 300, so that in the driving cycle of the pixel circuit, the reset control signal Scan1 has and only has one valid pulse, and in the driving cycle of the pixel circuit, the auxiliary control signal Scan3 also has and only has one valid pulse, so that the timing design can be simplified, the development cost can be reduced, and multiple valid pulses of the control signal can be avoided in one driving cycle, and the effective duration of the valid pulse can be shortened, which is not conducive to signal transmission.

[0065] In yet another optional embodiment, Figure 6 is a circuit structure diagram of another pixel circuit provided by an embodiment of the present invention, Figure 7 is a timing diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 6 and Figure 7 , the auxiliary module 300 is multiplexed as the reset unit 160, for example, the auxiliary transistor M14 can be multiplexed as the reset transistor M7; the working period of the reset module 160 is the same as the working period t3 of the auxiliary module 300. At this time, the effective period of the effective pulse of the reset control signal Scan1 is the working period t0 of the first initialization unit 170 and / or the second initialization unit 20.

[0066] Continue to refer Figure 6 and Figure 7 The working period t3 of the auxiliary module 300 includes a first working period t31 and a second working period t32. The first working period t31 does not overlap with the working period te1 of the light-emitting control unit 140, the working period te2 of the driving control unit 240, and the modulation phase tm of the modulation signal Sweep; the second working period t32 overlaps with at least one part of the working period te1 of the light-emitting control unit 140, the working period te2 of the driving control unit 240, and the modulation phase tm of the modulation signal Sweep.

[0067] Exemplary, reference Figure 6 and Figure 7In the first working period t31, the auxiliary module 300 can transmit the auxiliary reset signal RST to the first pole of the light-emitting element LED to reset the light-emitting element LED to clear the electrical signal of the light-emitting element LED in the current driving cycle or the previous driving cycle, which is beneficial to improve the accuracy of the light-emitting brightness of the light-emitting element LED; in the second working period t32, the auxiliary module 300 can transmit the auxiliary reset signal RST to the first pole of the light-emitting element LED to reset the light-emitting element LED to put the light-emitting element LED into a black state. By multiplexing the reset unit 160 and the auxiliary module 300, the hardware structure of the pixel circuit can be reduced, for example, the number of transistors in the pixel circuit can be reduced, which is beneficial to reducing the space occupied by the pixel circuit and improving the resolution.

[0068] Optional, Figure 8 is a circuit structure diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 8 The second driving unit 210 includes a second driving transistor M10, a first electrode of the second driving transistor M10 receives a third power supply signal VDD2, a second electrode of the second driving transistor M10 is electrically connected to the first driving unit 110, and a gate of the second driving transistor M10 is electrically connected to the coupling unit 230; the auxiliary module 300 includes an auxiliary transistor M14, a first electrode of the auxiliary transistor M14 receives an auxiliary reset signal, a second electrode of the auxiliary transistor M14 is electrically connected to the light-emitting element LED, and a gate of the auxiliary transistor M14 is electrically connected to the gate of the second driving transistor M10.

[0069] Exemplarily, the second driving transistor M10 and the auxiliary transistor M14 are of the same transistor type. For example, the second driving transistor M10 and the auxiliary transistor M14 may both be P-type transistors. Assume that the first driving unit 110 includes a first driving transistor M3, a first electrode of the first driving transistor M3 receives a first power signal VDD1, a second electrode of the first driving transistor M3 can be electrically connected to the second electrode of the auxiliary transistor M14, a gate of the first driving transistor M3 can be electrically connected to the second electrode of the second driving transistor M10, and the first driving transistor M3 is also a P-type transistor. When the voltage difference between the gate potential of the second driving transistor M10 and the third power signal VDD2 is less than or equal to the threshold voltage Vth(M10) (negative value) of the second driving transistor M10, the second driving transistor M10 is turned on. At this time, the gate potential of the first driving transistor M3 is the third power signal VDD2, the voltage difference between the gate potential of the first driving transistor M3 and the first power signal VDD1 is greater than the threshold voltage Vth(M3) (negative value) of the first driving transistor M3, the first driving transistor M3 is turned off, and the light-emitting element LED can be controlled to stop emitting light. Therefore, VDD2-VDD1>Vth(M3), that is, VDD2+|Vth(M3)|>VDD1.

[0070] In a conventional setting, the absolute value |Vth(M10)| of the threshold voltage Vth(M10) of the second driving transistor M10 and the absolute value |Vth(M3)| of the threshold voltage Vth(M3) of the first driving transistor M3 are both large, while the absolute values ​​of the threshold voltages of other transistors are all small, for example, the absolute value |Vth(M14)| of the threshold voltage Vth(M14) of the auxiliary transistor M14 is small. Therefore, in an embodiment of the present invention, the voltage of the first power supply signal VDD1 can be set to be smaller than the voltage of the third power supply signal VDD2. The gate potential of the second driving transistor M10 is equal to the gate potential of the auxiliary transistor M14. When the second driving transistor M10 is in the critical conduction state, the voltage difference between the gate potential of the second driving transistor M10 and the third power supply signal VDD2 is equal to the threshold voltage Vth(M10) (negative value) of the second driving transistor M10. At this time, the voltage difference between the gate potential of the auxiliary transistor M14 and the first power supply signal VDD1 can also be equal to the threshold voltage Vth(M14) (negative value) of the auxiliary transistor M14, so that the auxiliary transistor M14 and the second driving transistor M10 can be turned on at the same time. On the one hand, when the second driving transistor M10 is turned on, the light-emitting element LED can be timely controlled to enter the black state through the auxiliary transistor M14, so that when the second driving transistor M10 is turned on, the third power supply signal VDD2 provided by the second driving transistor M10 to the first driving transistor M3 is not distorted, resulting in the first driving transistor M3 being unable to be turned off in time, affecting the light-emitting duration of the light-emitting element LED; on the other hand, there is no need to separately design a control signal and a control signal line for the auxiliary transistor M14, which is beneficial to reducing signal routing and simplifying timing design, and can also avoid the working period of the auxiliary module 300 being inconsistent with the working period of the second driving unit 210, affecting the display grayscale.

[0071] In an optional embodiment, the voltage of the first power signal VDD1 is less than the voltage of the third power signal VDD2; the voltage of the first power signal VDD1 is equal to the voltage of the third power signal VDD2 minus a preset compensation value.

[0072] In one embodiment, the preset compensation value may be the absolute value |Vth(M10)| of the threshold voltage Vth(M10) of the second driving transistor M10. For example, the preset compensation value may be obtained by testing or calculating the average value, median, etc. of the absolute values ​​|Vth(M10)| of the threshold voltages Vth(M10) of the plurality of auxiliary transistors M10. Thus, when the second driving transistor M10 is in the critical conduction state, the voltage VN2 of the second node N2 is VDD2-|Vth(M10)|, the gate-source voltage VGS(M14) of the auxiliary transistor M14 is VN2-VDD1=0, and the auxiliary transistor M14 is also in the critical conduction state, so that the auxiliary transistor M14 and the second driving transistor M10 are turned on at the same time (the absolute value |Vth(M14)| of the threshold voltage Vth(M14) of the auxiliary transistor M14 is small and can be ignored).

[0073] In another embodiment, the preset compensation value may be the value of the absolute value |Vth(M10)| of the threshold voltage Vth(M10) of the second driving transistor M10 minus the absolute value |Vth(M14)| of the threshold voltage Vth(M14) of the auxiliary transistor M14. Thus, when the second driving transistor M10 is in the critical conduction state, the voltage VN2 of the second node N2 = VDD2 - |Vth(M10)|, the gate-source voltage VGS(M14) of the auxiliary transistor M14 = VN2 - VDD1 = - |Vth(M14)|, and the auxiliary transistor M14 is also in the critical conduction state, so that the auxiliary transistor M14 and the second driving transistor M10 are turned on at the same time (the threshold voltage Vth(M14) of the auxiliary transistor M14 is not ignored).

[0074] Optional, Fig. 9 is a timing diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 4 and Fig. 9 , the driving cycle of the pixel circuit includes at least a writing stage TS and a driving stage TD; the working period t21 of the first writing unit 120 and the working period t22 of the second writing unit 220 overlap with the writing stage TS; the working period te1 of the light emitting control unit 140, the working period te2 of the driving control unit 240 and the modulation stage tm of the modulation signal Sweep overlap at least part of the driving stage TD. The driving stage TD includes a first driving stage td1 and a second driving stage td2; in the first driving stage td1, the light emitting element LED emits light; in the second driving stage td2, the light emitting element stops emitting light LED; the second driving stage td2 of the same driving stage TD is located after the first driving stage td1; the working period t3 of the auxiliary module 300 overlaps with the second driving stage td2; the working period t3 of the auxiliary module 300 does not overlap with the first driving stage td1.

[0075] Exemplarily, the driving stage TD includes the working period t3 of the auxiliary module 300, the working period te1 of the light emitting control unit 140, the working period te2 of the driving control unit 240, and the modulation stage tm of the modulation signal Sweep. The first driving stage td1 includes a part of the working period te1 of the light emitting control unit 140. In the first driving stage td1, the light emitting control unit 140 of the PAM module 100 can control the first driving unit 110 to provide the transmission path of the first driving signal to the light emitting element LED to be turned on. The first driving unit 110 can form a driving current of a corresponding magnitude according to the first data signal Data1, and provide it to the light emitting element LED, so that the light emitting element LED can emit light of a corresponding brightness according to the first data signal Data1.

[0076] The first driving stage td1 may also include a part of the working period te2 of the driving control unit 240 and a part of the modulation stage tm of the modulation signal Sweep. In the first driving stage td1, the driving control unit 240 may control the second driving unit 210 to provide the first driving unit 110 with a transmission path for the third power supply signal VDD2 to be turned on, and the modulation signal Sweep changes. For example, the second driving unit 210 includes a second driving transistor M10, and the second driving transistor M10 is a P-type transistor. The voltage of the modulation signal Sweep in this stage is greater than the voltage of the modulation signal Sweep before this stage, and the voltage of the modulation signal Sweep in this stage is relatively large. The coupling unit 230 will also couple the potential of the second node N2 to a higher potential, so that the second driving transistor M10 is turned off, the third power supply signal VDD2 is not transmitted to the first node N1, and the first driving unit 110 can provide a driving current to the light-emitting element LED, so that the light-emitting element LED can emit light of corresponding brightness according to the first data signal Data1. The first driving stage td1 does not overlap with the working period t3 of the auxiliary module 300 to ensure that when the voltage of the modulation signal Sweep is large and the second driving transistor M10 is turned off, the auxiliary module 300 will not control the light emitting element LED to enter the black state prematurely to affect the displayed grayscale.

[0077] The second driving stage td2 includes a part of the working period te2 of the driving control unit 240 and a part of the modulation stage tm of the modulation signal Sweep. In the second driving stage td2, the driving control unit 240 can control the second driving unit 210 to provide the first driving unit 110 with a transmission path for the third power supply signal VDD2 to be turned on. For example, the second driving unit 210 includes a second driving transistor M10, and the second driving transistor M10 is a P-type transistor. In this stage, the voltage of the modulation signal Sweep is lower than the voltage of the modulation signal Sweep in the first driving stage td1. In this stage, the voltage of the modulation signal Sweep is small, and the coupling unit 230 couples and pulls down the potential of the second node N2, so that the second driving transistor M10 is turned on, the third power supply signal VDD2 is transmitted to the first node N1, and the first driving unit 110 stops providing the driving current to the light-emitting element LED, and the light-emitting element LED stops emitting light.

[0078] The second driving stage td2 also includes at least part of the working period t3 of the auxiliary module 300 to ensure that when the voltage of the modulation signal Sweep is small and the second driving transistor M10 is turned on, the auxiliary module 300 can control the light-emitting element LED to enter the black state in time to avoid distortion of the third power supply signal VDD2, resulting in the first driving unit 110 being unable to stop providing the driving current in time when the second driving transistor M10 is turned on, causing the light-emitting element LED that should have entered the black state to continue to emit light, affecting the displayed grayscale.

[0079] In addition, the second driving stage td2 may also include a partial period of the working period te1 of the light emitting control unit 140. After the coupling unit 230 is coupled, whether the second driving transistor M10 can be turned on needs to refer to the voltage of the second data signal Data2 written to the second node N2 in the working period t22 of the second writing unit 220 and the change in the voltage of the modulation signal Sweep in the modulation stage tm of the modulation signal Sweep. Therefore, the second driving transistor M10 is turned on, and the duration of controlling the first driving unit 110 to stop providing the driving current to the light emitting element LED can be determined by the voltage of the second data signal Data2. The second driving stage td2 includes a part of the working period te1 of the light emitting control unit 140. In different driving cycles, the voltage of the second data signal Data2 can be controlled to change the part of the second driving stage td2 into the first driving period td2 to increase the light emitting time of the light emitting element LED. Similarly, the voltage of the second data signal Data2 can be controlled to change the part of the first driving stage td1 into the second driving period td2 to shorten the light emitting time of the light emitting element LED. The light emitting time of the light emitting element LED can be flexibly adjusted, thereby flexibly controlling the display grayscale. Wherein, no matter how the first driving stage td1 and the second driving period td2 change, the first driving stage td1 does not overlap with the working period t3 of the auxiliary module 300.

[0080] It should be noted that the voltage of the modulation signal can first jump to a higher potential and then gradually decrease until it recovers to the potential before the jump as shown in the accompanying drawings. In other embodiments, the voltage of the modulation signal can also first jump to a lower potential and then gradually increase until it recovers to the potential before the jump, or first gradually increase and then jump to the potential before the change, or first gradually decrease and then jump to the potential before the change. The modulation waveform of the modulation signal can be set according to actual needs, and the embodiments of the present invention do not make specific limitations on this.

[0081] It should also be noted that the driving cycle of the pixel circuit includes but is not limited to a writing phase and a driving phase. In other embodiments, the driving cycle of the pixel circuit may also include an initialization phase, a reset phase, etc., wherein the contents of the initialization phase and the reset phase have been exemplarily described in the above content and will not be described one by one here.

[0082] In an optional embodiment, the overlapping time length of the working period t3 of the auxiliary module 300 and the driving stage TD is the time length of the second driving stage td2.

[0083] Specifically, in the working period t3 of the auxiliary module 300, the light emitting element LED is in a black state and does not emit light. The proportion of the working period t3 of the auxiliary module 300 in the driving stage TD is the duration of the light emitting element LED being in a black state after the first driving stage td1 in the driving stage TD, that is, the duration of the second driving stage td2. In this way, by setting the overlapping duration of the working period t3 of the auxiliary module 300 and the driving stage TD, the duration of the second driving stage td2 can be set, so that the duration of the first driving stage td1 can be determined, and the precise control of the light emitting duration of the light emitting element LED can be achieved.

[0084] Based on the above embodiment, the second driving stage td2 accounts for less than or equal to 70% of the driving stage TD. In this way, the duration of the first driving stage td1 can account for more than or equal to 30% of the driving stage TD, so that the light-emitting element LED has sufficient time to charge and discharge, which can avoid the light-emitting element LED being in the bright state for too short a time, affecting the precise control of the light-emitting duration of the light-emitting element LED.

[0085] In yet another optional embodiment, continue to refer to Figure 4 and Fig. 9 , the second driving unit 210 includes a second driving transistor M10, a first electrode of the second driving transistor M10 receives the third power signal VDD2, a second electrode of the second driving transistor M10 is electrically connected to the first driving unit 110, and a gate of the second driving transistor M10 is electrically connected to the coupling unit 230. The voltage of the third power signal VDD2 is V2; the voltage of the second data signal Data is Vdata2; in the modulation stage tm, the voltage of the modulation signal Sweep changes linearly with a slope of k; at the switching moment between the first driving stage td1 and the second driving stage td2, compared with the non-modulation stage, the voltage change of the modulation signal Sweep is △V=|V2-Vdata2|; the overlapping time length of the working period t3 of the auxiliary module 300 and the modulation stage tm is △V / k.

[0086] Exemplarily, taking the second driving transistor M10 as a P-type transistor, when the voltage of the modulation signal Sweep increases more than that in the non-modulation stage, the second driving transistor M10 can continue to remain in the off state, so that the first driving unit 110 can continue to provide driving current for the light-emitting element LED; when the voltage of the modulation signal Sweep increases less than that in the non-modulation stage, the gate-source voltage VGS(M10)=VN2-V2=[Vdata2-|Vth(M10)|+△V]-V2 of the second driving transistor M10 may be less than or equal to -|Vth(M10)|, and the second driving transistor M10 is turned on, so that the first driving unit 110 stops providing driving current for the light-emitting element LED. When △V=V2-Vdata2, the second driving transistor M10 is in a critical conduction state, and the duration from the moment when the second driving transistor M10 is in the critical conduction state to the end moment of the modulation stage tm is △V / k.

[0087] By setting the overlapping time length of the working period t3 of the auxiliary module 300 and the modulation stage tm to △V / k, the moment when the auxiliary module 300 controls the light-emitting element LED to enter the black state can change with the change of Vdata2, that is, the working period t3 of the auxiliary module 300 can change with the change of the switching time between the bright state and the black state, which can ensure that the auxiliary module 300 can flexibly and accurately control the light-emitting duration of the LED according to the second data signal Data, and avoid the working period t3 of the auxiliary module 300 controlling the light-emitting element LED to enter the black state in advance or lagging, which affects the displayed grayscale.

[0088] Optional, Fig.10 is a timing diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 4 and Fig.10 , the termination time of the driving phase TD overlaps with the working period t3 of the auxiliary module 300.

[0089] Exemplarily, the driving stage TD includes the working period te1 of the light emitting control unit 140, the working period te2 of the driving control unit 240, and the modulation period tm of the modulation signal Sweep. In the same driving cycle, the termination time of the working period t3 of the auxiliary module 300 may overlap with the termination time of the driving stage TD, or the termination time of the working period t3 of the auxiliary module 300 may also be located after the termination time of the driving stage TD; wherein, the termination time of the working period t3 of the auxiliary module 300 may be located before the next driving cycle, or before the first driving period td1 of the next cycle.

[0090] In this way, the end time of the working period t3 of the auxiliary module 300 can be located after the end time of the working period te1 of the light-emitting control unit 140, so as to ensure that before the end time of the working period te1 of the light-emitting control unit 140, the auxiliary module 300 can always control the light-emitting element LED to be in the black state, so as to avoid the first driving transistor M3 being turned on due to the distortion of the third power supply signal VDD after the end time of the working period t3 of the auxiliary module 300, causing the light-emitting element LED that should be in the black state to display light and affect the display grayscale.

[0091] Optional, Fig.11 is a timing diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 4 and Fig.11 , the termination time of the modulation phase tm of the modulation signal Sweep overlaps with the working period te1 of the light emitting control unit 140; and / or, the termination time of the modulation phase tm of the modulation signal Sweep overlaps with the working period te2 of the driving control unit 240.

[0092] Exemplarily, the end time of the modulation phase tm of the modulation signal Sweep overlaps with the end time of the working period te1 and / or the working period te2, or the end time of the modulation phase tm of the modulation signal Sweep is located before the end time of the working period te1 and / or the working period te2. In this way, it can be ensured that when the second driving transistor M10 is turned on near the end time of the modulation phase tm, the third power supply signal VDD2 can be transmitted to the first node N1 through the second driving transistor M10 and the driving control unit 240, so that the light-emitting element LED can enter the black state of the driving phase TD; it is avoided that when the second driving transistor M10 is turned on near the end time of the modulation phase tm, the LED cannot be controlled to enter the black state, which is not conducive to accurate control of the gray scale.

[0093] Optional, Fig.12 is a timing diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 4 and Fig.12 , the end time of the working period te2 of the driving control unit 240 overlaps with the working period te1 of the light emitting control unit 140.

[0094] Exemplarily, the end time of the working period te2 of the driving control unit 240 overlaps with the end time of the working period te1 of the light emitting control unit 140, or the end time of the working period te2 of the driving control unit 240 is before the end time of the working period te1 of the light emitting control unit 140. After the end time of the working period te1, the first driving unit 110 stops providing the driving current to the light emitting element LED, and the light emitting element LED enters the black state. The end time of the working period te2 overlaps with the working period te1, which can ensure that the second driving unit 210 and the driving control unit 240 can stop transmitting the third power supply signal VDD2 to the first driving unit 110 after the first driving unit 110 stops providing the driving current to the light emitting element LED, which can reduce the leakage current of the first driving unit 110 and the light emitting control unit 140, and avoid the leakage current affecting the black state of the light emitting element LED.

[0095] Optional, Fig.13 is a timing diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 4 and Fig.13 , the starting time of the working period te1 of the light emitting control unit 140 overlaps with the modulation phase tm of the modulation signal Sweep; and / or, the starting time of the working period te2 of the driving control unit 240 overlaps with the working period te1 of the light emitting control unit 140.

[0096] Exemplarily, taking the second driving unit 210 including the second driving transistor M10, where the second driving transistor M10 is a P-type transistor, at the start time of the modulation phase tm of the modulation signal Sweep, the voltage of the modulation signal Sweep jumps to a higher level in a short time, and the coupling unit 230 can couple the voltage of the second node N2 to a higher level, and control the second driving transistor M10 not to turn on. At this time, the second driving transistor M10 does not provide the third power supply signal VDD2 to the first driving unit 110.

[0097] The starting time of the working period te1 of the light-emitting control unit 140 is located after the starting time of the modulation stage tm of the modulation signal Sweep, which can ensure that at the beginning of the working period te1 of the light-emitting control unit 140, the voltage of the second node N2 has been coupled to a higher level by the coupling unit 230, and the second driving transistor M10 is turned off, thereby preventing the third power supply signal VDD2 from being transmitted to the first driving unit 110; and / or, the starting time of the working period te2 of the driving control unit 240 is located after the starting time of the working period te1 of the light-emitting control unit 140, which can ensure that at the beginning of the working period te1 of the light-emitting control unit 140, the driving control unit 240 is not in the working period te2, and can also prevent the third power supply signal VDD2 from being transmitted to the first driving unit 110 at the beginning of the working period te1 of the light-emitting control unit 140, affecting the accuracy of the first data signal Data1 stored in the first node N1, and further affecting the light-emitting brightness of the light-emitting element LED.

[0098] Optional, Fig.14 is a timing diagram of another pixel circuit provided by an embodiment of the present invention, referring to Figure 4 and Fig.14 , the starting time of the working period te1 of the driving control unit 240 overlaps with the modulation phase tm of the modulation signal Sweep.

[0099] Exemplarily, taking the case where the second driving unit 210 includes a second driving transistor M10, and the second driving transistor M10 is a P-type transistor, at the start time of the modulation phase tm of the modulation signal Sweep, the voltage of the modulation signal Sweep jumps to a higher level in a short time. The start time of the modulation phase tm of the modulation signal Sweep is located before the start time of the working period te1 of the driving control unit 240, so as to ensure that when the driving control unit 240 controls the second driving transistor M10 to provide the first driving unit 110 with the third power supply signal VDD2, the voltage of the second node N2 has been coupled to a higher level by the coupling unit 230, and the second driving transistor M10 can be in a turned-off state, so as to avoid the third power supply signal VDD2 being transmitted to the first driving unit 110 at the beginning of the working period te1 of the driving control unit 240, thereby affecting the accuracy of the first data signal Data1 stored in the first node N1, and further affecting the light emitting brightness of the light emitting element LED.

[0100] Among them, when the starting time of the working period te1 of the driving control unit 240 overlaps with the modulation stage tm of the modulation signal Sweep, the starting time of the working period te2 of the driving control unit 240 can be located before the starting time of the working period te1 of the light-emitting control unit 140. At the beginning of the working period te1 of the light-emitting control unit 140, the voltage of the second node N2 has been coupled to a higher level by the coupling unit 230, and the second driving transistor M10 is turned off. Regardless of whether the driving control unit 240 is in the working period te2, the third power supply signal VDD2 can be avoided from being transmitted to the first driving unit 110, thereby affecting the light-emitting element LED to display light; at the same time, it should be avoided that the starting time of the working period te2 of the driving control unit 240 is located before the modulation stage tm of the modulation signal Sweep. In this way, it can be ensured that when the driving control unit 240 is in the early stage of the working period te2, the third power supply signal VDD2 will not be transmitted to the first driving unit 110, thereby avoiding affecting the written first data signal Data1.

[0101] Based on the same inventive concept, an embodiment of the present invention further provides a display panel, Fig.15 is a schematic diagram of a top view structure of a display panel provided by an embodiment of the present invention, with reference to Fig.15 The display panel 01 includes a display area AA and a non-display area NA. The display panel 01 also includes a plurality of pixels P located in the display area AA. The pixel P includes a pixel circuit 41 and a light-emitting element LED. The pixel circuit 41 may be a pixel circuit provided by any embodiment of the present invention.

[0102] Exemplarily, each pixel circuit 41 includes the auxiliary module 300 described in any of the above embodiments. The control end of the auxiliary module 300 can receive an auxiliary control signal. When the auxiliary control signal is at a valid level, the auxiliary module 300 resets the light-emitting element LED to put the light-emitting element LED into a black state, so as to accurately control the light-emitting time of the light-emitting element LED, so as to achieve precise control of the display grayscale and improve the display effect.

[0103] In one embodiment, each pixel circuit 41 can receive an auxiliary control signal, and two adjacent pixel circuits 41 can receive different auxiliary control signals, which is conducive to accurately controlling the light emission duration of the light-emitting element LED of each pixel P, realizing accurate control of the display grayscale, and improving the contrast.

[0104] Optional, continue to refer to Fig.15The display panel 01 further includes a signal receiving terminal 50, the pixel circuit 41 includes a first pixel circuit 401 and a second pixel circuit 402, and the first pixel circuit 401 is located on a side of the second pixel circuit 402 away from the signal receiving terminal 50. The first pixel circuit 41 includes an auxiliary module 300; the second pixel circuit does not include the auxiliary module, and / or the second pixel circuit includes the auxiliary module 300, but the auxiliary module 300 does not work.

[0105] Exemplarily, the display panel 01 may include a plurality of signal receiving terminals 50, and the signal receiving terminals 50 may be used to receive signals such as power supply signals, auxiliary control signals, and clock signals provided to the pixel circuit 41. The display panel 01 also includes a plurality of signal lines (not shown in the figure) connecting the signal receiving terminals 50 and the pixel circuit 40, and these signal lines are used to transmit signals provided to the pixel circuit 41. The signal lines may include a first signal line and a second signal line, and the first signal line is used to connect the receiving terminal 50 and the first pixel circuit 401, and the second signal line is used to connect the receiving terminal 50 and the first pixel circuit 402 (not shown in the figure). The first pixel circuit 41 is far away from the signal receiving terminal 50, and the second pixel circuit 402 is close to the signal receiving terminal 50. Therefore, the first signal line is longer and / or has a larger load, resulting in a more obvious voltage drop on the first signal line, and the signal transmitted to the first pixel circuit is more easily distorted; the second signal line is shorter and / or has a smaller load, so that the voltage drop on the second signal line is smaller, and the signal transmitted to the first pixel circuit is not easily distorted.

[0106] By setting the second pixel circuit 402 closer to the signal receiving end 50 to not include the auxiliary module, and / or the second pixel circuit includes the auxiliary module 300 but the auxiliary module 300 is not working, the number of signal lines can be effectively reduced, especially the number of second signal lines for transmitting auxiliary control signals, which is conducive to simplifying the structural design and reducing the difficulty of the process.

[0107] In one embodiment, if the second pixel circuit 402 closer to the signal receiving end 50 includes an auxiliary module 300, the control end of the auxiliary module 300 in the second pixel circuit 402 can be connected to a signal of a fixed potential, so that the auxiliary module 300 in the second pixel circuit 402 is always in a non-working state, and the control end of the auxiliary module 300 in the first pixel circuit 401 can receive an auxiliary control signal including a valid pulse.

[0108] Optionally, the auxiliary module 300 of the pixel circuit 41 is used to reset the light-emitting element LED under the control of an auxiliary control signal; the auxiliary control signal received by at least part of the pixel circuits 41 multiplexes the auxiliary control signal received by adjacent pixel circuits 41 .

[0109] Specifically, the distance between adjacent pixel circuits 41 is relatively close, and the distance between pixels P where adjacent pixel circuits 41 are located is also relatively close. Therefore, the grayscale of pixels P where adjacent pixel circuits 41 are located is also relatively close. The same auxiliary control signal can be provided to the adjacent pixel circuits 41, which is beneficial to reducing the signal lines used to transmit auxiliary control signals, simplifying the structural design, reducing the difficulty of the process, and at the same time, the impact on the display effect is also relatively small.

[0110] Based on the same inventive concept, an embodiment of the present invention further provides a display device, Fig.16 is a schematic diagram of the structure of a display device provided by an embodiment of the present invention, such as Fig.16 The display device 02 includes a display panel 01 provided by any embodiment of the present invention. The display device 02 provided by the embodiment of the present invention can be Fig.16 The mobile phone shown can also be any electronic product with a display function, including but not limited to the following categories: televisions, laptops, desktop displays, tablet computers, digital cameras, smart bracelets, smart glasses, car displays, medical equipment, industrial control equipment, touch interactive terminals, etc. The embodiments of the present invention do not specifically limit this.

[0111] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A pixel circuit, characterized in that: include: Light emitting element, pulse amplitude modulation module, pulse width modulation module and auxiliary module; The pulse amplitude modulation module includes a first driving unit, a first writing unit, a storage unit and a light emitting control unit; the first driving unit is used to provide a first driving signal to the light emitting element; the first writing unit is used to write a first data signal to the first driving unit; the storage unit is used to store the first data signal to the first driving unit; The light emitting control unit is used to control the first driving unit to provide a transmission path of the first driving signal to the light emitting element; The pulse width modulation module includes a second driving unit, a second writing unit, a driving control unit and a coupling unit; the second driving unit is used to provide a second driving signal to the first driving unit; the second writing unit is used to write a second data signal to the second driving unit; the coupling unit is used to couple the variation of the modulation signal to the second driving unit; the driving control unit is used to control the transmission path of the second driving signal provided by the second driving unit to the first driving unit; The auxiliary module is used to reset the light emitting element; wherein the working period of the auxiliary module overlaps with at least one of the working period of the light emitting control unit, the working period of the driving control unit and the modulation phase of the modulation signal.

2. The pixel circuit according to claim 1, characterized in that: The pulse amplitude modulation module also includes a reset unit; The reset unit is also used to reset the; wherein, at least part of the working period of the reset unit does not overlap with the working period of the light emitting control unit, the working period of the driving control unit and the modulation phase of the modulation signal.

3. The pixel circuit according to claim 2, characterized in that: The pulse amplitude modulation module further includes a first initialization unit; the first initialization unit is used to initialize the first driving unit; And / or, the pulse width modulation module further includes a second initialization unit; the second initialization unit is used to initialize the second driving unit; The working period of the reset unit is the same as the working period of the first initialization unit and / or the second initialization unit, and the working period of the reset unit does not overlap with the working period of the auxiliary module.

4. The pixel circuit according to claim 2, characterized in that: The auxiliary module is multiplexed as the reset unit; The working period of the auxiliary module includes a first working period and a second working period; The first working period does not overlap with the working period of the light emitting control unit, the working period of the driving control unit, and the modulation phase of the modulation signal; The second working period overlaps with at least one of a working period of the light emitting control unit, a working period of the driving control unit and a modulation phase of the modulation signal.

5. The pixel circuit according to claim 1, characterized in that: The second driving unit includes a second driving transistor, a first electrode of the second driving transistor receives a third power supply signal, a second electrode of the second driving transistor is electrically connected to the first driving unit, and a gate of the second driving transistor is electrically connected to the coupling unit; The auxiliary module includes an auxiliary transistor, a first electrode of the auxiliary transistor receives an auxiliary reset signal, a second electrode of the auxiliary transistor is electrically connected to the light emitting element, and a gate of the auxiliary transistor is electrically connected to a gate of the second driving transistor.

6. The pixel circuit according to claim 5, characterized in that: The first driving unit comprises a first driving transistor, a first electrode of the first driving transistor receives a first power supply signal, and a second electrode of the first driving transistor is electrically connected to a second electrode of the auxiliary transistor; The voltage of the first power signal is less than the voltage of the third power signal; the voltage of the first power signal is equal to the voltage of the third power signal minus a preset compensation value.

7. The pixel circuit according to claim 1, characterized in that: The driving cycle of the pixel circuit at least includes a writing phase and a driving phase; The working period of the first writing unit and the working period of the second writing unit both overlap with the writing phase; The working period of the light emitting control unit, the working period of the driving control unit and the modulation phase of the modulation signal overlap simultaneously in at least a part of the driving phase; The driving stage includes a first driving stage and a second driving stage; In the first driving stage, the light emitting element emits light; In the second driving stage, the light emitting element stops emitting light; The second driving stage of the same driving stage is located after the first driving stage; The working period of the auxiliary module overlaps with the second driving phase; the working period of the auxiliary module does not overlap with the first driving phase.

8. The pixel circuit according to claim 7, characterized in that: The overlapping time length of the working period of the auxiliary module and the driving phase is the duration of the second driving phase.

9. The pixel circuit according to claim 8, characterized in that: The second driving stage accounts for less than or equal to 70% of the driving stage.

10. The pixel circuit according to claim 7, characterized in that: The second driving unit includes a second driving transistor, a first electrode of the second driving transistor receives a third power supply signal, a second electrode of the second driving transistor is electrically connected to the first driving unit, and a gate of the second driving transistor is electrically connected to the coupling unit; The voltage of the third power signal is V2; the voltage of the second data signal is Vdata2; In the modulation stage, the voltage of the modulation signal changes linearly, and the slope is k; At the switching moment between the first driving stage and the second driving stage, compared with the non-modulation stage, the voltage change of the modulation signal is ΔV=|V2-Vdata2|; The overlapping time length of the working period of the auxiliary module and the modulation phase is ΔV / k.

11. The pixel circuit according to claim 7, characterized in that: The termination time of the driving phase overlaps with the working period of the auxiliary module.

12. The pixel circuit according to claim 1, characterized in that: The termination time of the modulation phase of the modulation signal overlaps with the working period of the light emitting control unit; And / or, the termination time of the modulation phase of the modulation signal overlaps with the working period of the driving control unit.

13. The pixel circuit according to claim 1, characterized in that: The end time of the working period of the driving control unit overlaps with the working period of the lighting control unit.

14. The pixel circuit according to claim 1, characterized in that: The starting time of the working period of the light emitting control unit overlaps with the modulation phase of the modulation signal; And / or, the starting time of the working period of the driving control unit overlaps with the working period of the lighting control unit.

15. The pixel circuit according to claim 1, characterized in that: The starting time of the working period of the driving control unit overlaps with the modulation phase of the modulation signal.

16. A display panel, characterized in that: The invention comprises a plurality of pixel circuits as described in any one of claims 1 to 15.

17. The display panel according to claim 16, characterized in that: Also includes a signal receiving end; The pixel circuit includes a first pixel circuit and a second pixel circuit; the first pixel circuit is located at a side of the second pixel circuit away from the signal receiving end; The first pixel circuit includes the auxiliary module; The second pixel circuit does not include the auxiliary module; and / or the second pixel circuit includes the auxiliary module, but the auxiliary module does not work.

18. The display panel according to claim 16, characterized in that: The auxiliary module of the pixel circuit is used to reset the light emitting element under the control of an auxiliary control signal; The auxiliary control signal received by at least part of the pixel circuits multiplexes the auxiliary control signal received by adjacent pixel circuits.

19. A display device, characterized in that: A display panel comprising any one of claims 16 to 18.

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