A display circuit, a display method, a display device, and an electronic device

Abstract

Embodiments of the present application provide a display circuit, a display method, a display device and an electronic device, which are applied to the technical field of light emitting diode driving. A plurality of current source branches and a plurality of pixel branches are arranged in the display circuit. Each current source branch comprises a first transistor and a control circuit. Each pixel branch comprises a second transistor, a pulse width control switch tube and a pixel unit in series. The turned-on first transistor and the turned-on second transistor constitute a current mirror structure. Under the current mirror structure, the current flowing through the plurality of first transistors is in proportional relationship with the current flowing through the turned-on second transistor. Whether each first transistor is turned on or not is controlled by the control circuit, so as to adjust the size of the current flowing through each pixel unit through the second transistor. Embodiments of the present application adjust the size of the current flowing through the plurality of current source branches, so as to control the size of the current flowing through the pixel unit, and further to reduce the waste of power consumption as much as possible.

Description

[0001] This application claims priority to Chinese Patent Application No. 202210719596.5, filed on June 23, 2022, entitled "A Light-Emitting Driving Circuit, a Light-Emitting Driving Method and an Electronic Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of light-emitting diode (LED) driving technology, and in particular to a display circuit, display method, display device and electronic device. Background Technology

[0003] One current driving method for LEDs is current driving. Current driving refers to providing a constant driving current to the LED, meaning the magnitude of the driving current is a fixed value, and then using pulse width modulation (PWM) to adjust the proportion of time the LED's branch is on.

[0004] One current-driven implementation involves providing a constant reference current, generating multiple constant drive currents based on this reference current, and outputting them to the corresponding LEDs on multiple branches. In this method, because the magnitude of the reference current cannot be adjusted, the constant reference current results in wasted power consumption. Furthermore, providing a large reference current when only a few branches need to be active also leads to wasted power consumption. Summary of the Invention

[0005] This application provides a display circuit, display method, display device, and electronic device that realizes the adjustment of the magnitude of a reference current.

[0006] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0007] In a first aspect, a display circuit is provided; the display circuit includes multiple current source branches and multiple pixel branches; each of the multiple current source branches includes a control circuit and a first transistor; each control circuit is coupled to a corresponding first transistor; each of the multiple pixel branches includes a second transistor, a pulse width control switch, and a pixel unit connected in series; the second transistor is coupled to the gate of the first transistor, and the second transistor and the conducting first transistor form a current mirror; the pulse width control switch is used to control the conduction and disconnection of the corresponding pixel branch; the control circuit is used to control the conduction and disconnection of the corresponding first transistor.

[0008] In this embodiment, the first transistors in multiple current source branches and the second transistors in multiple pixel branches respectively constitute a current mirror structure. In the current mirror structure, the magnitude of the second current flowing through the first transistor is in a fixed ratio to the magnitude of the first current flowing through the second transistor. According to the characteristics of the current mirror, this ratio is determined by the ratio between a first ratio and a second ratio. The first ratio is the ratio of the channel width W1 to the channel length L1 of the first transistor, W1 / L1, and the second ratio is the ratio of the channel width W2 to the channel length L2 of the second transistor, W2 / L2. By controlling the number of current source branches that are conducting, the total magnitude of the second current output by the multiple current source branches can be controlled, thereby adjusting the magnitude of the first current flowing through the pixel branches. The first current flowing through the pixel branches is output as a driving current to the pixel unit to drive the pixel unit to emit light. The second current, as a reference current determining the magnitude of the first current, is always present. When a pixel branch does not need to emit light, it does not need to flow with the first current. However, the current source branch still outputs a second current as a reference current, which wastes power. Furthermore, when multiple pixel branches are configured, the more pixel branches there are, the larger the first current needs to be to meet the fast response drive requirements of the pixel branches. To ensure that the first current can meet the application scenario where all pixel units in multiple pixel branches emit light simultaneously and still respond quickly within the specified drive time, the first current needs to be set as large as possible, and the total magnitude of the second current output by the current source branch also needs to be set as large as possible. However, if only some pixel units in multiple pixel branches need to emit light, a larger first and second current, while meeting the fast response requirements of those pixel branches within the specified drive time, will still result in some wasted power. To avoid the aforementioned power waste, in this embodiment, multiple current source branches are configured in the current source branch, with each current source branch outputting one second current. By adjusting whether each current source branch in a plurality of current source branches outputs a second current, the total magnitude of the second current output by the current source branches is dynamically adjusted. This total magnitude of the second current is then used to adjust the magnitude of the first current.

[0009] In one possible implementation, the control circuit includes a first switch and a second switch; the first switch is coupled between a first electrode of a first transistor and the gate of the first transistor; the second switch is coupled between a second electrode of the first transistor and the gate of the first transistor.

[0010] In this embodiment, when the first transistor is turned on, and a current mirror structure is formed between the turned-on first transistor and the second transistor, the gate of the first transistor is coupled to the gate of the second transistor, making the gate voltage of the first transistor equal to the gate voltage of the second transistor. When the second terminal of the first transistor is coupled to the gate of the first transistor, the first transistor is in a turned-off state. At this time, the first terminal of the first transistor will not output a second current, and the magnitude of the second current output by multiple first transistors will be reduced. When the first terminal of a certain first transistor is coupled to the gate of the first transistor, the first transistor is turned on, and a second current flows through the first and second terminals of the first transistor, and the first transistor and the second transistor form a current mirror (CM) structure. For multiple current source branches, all conducting first transistors in multiple constant current sources form a current mirror structure with the second transistors. The sum of the multiple second currents output by all conducting first transistors is used as the reference current. The first current flowing through the second transistor after it is turned on is proportional to the total current of all second currents. According to the characteristics of the current mirror, this proportional relationship is determined by the ratio between the first ratio and the second ratio. The first ratio is the ratio of the channel width W1 of the first transistor to the channel length L1, W1 / L1. The second ratio is the ratio of the channel width W2 of the second transistor to the channel length L2, W2 / L2.

[0011] In one possible implementation, for different current source branches, the ratio of the channel width to the channel length of the first transistor in the first current source branch is equal to the ratio of the channel width to the channel length of the first transistor in the second current source branch.

[0012] In this embodiment, the magnitude of the output second current can be equal between different current source branches. For example, there are two current source branches, namely a first current source branch and a second current source branch. Then, the channel width of the first transistor in the first current source branch is W. 11 The channel length of the first transistor in the first current source branch is L. 11 The channel width of the first transistor in the second current source branch is W. 12 The channel length of the first transistor in the second current source branch is L. 12 When W 11 =W 12 L 11 =L 12 At this time, the magnitude of the second current output by the first transistor in the first current source branch is equal to the magnitude of the second current output by the first transistor in the second current source branch. Therefore, adjusting the number of conducting current source branches is sufficient to adjust the sum of the second currents.

[0013] In one possible implementation, for different current source branches, the ratio of the channel width to the channel length of the first transistor in the first current source branch is k times the ratio of the channel width to the channel length of the first transistor in the second current source branch.

[0014] In this embodiment, the magnitude of the output second current increases proportionally between different current source branches. For example, there are two current source branches, namely a first current source branch and a second current source branch. Then, the channel width of the first transistor in the first current source branch is W. 11 The channel length of the first transistor in the first current source branch is L. 11 The channel width of the first transistor in the second current source branch is W. 12 The channel length of the first transistor in the second current source branch is L. 12 When W 11 / L 11 The value of W 12 / L 12 When the ratio between the values ​​is k, the magnitude of the second current output by the first transistor in the first current source branch is k times proportional to the magnitude of the second current output by the first transistor in the second current source branch. In this case, besides adjusting the number of current source branches that are active in the multiple current source branches to adjust the sum of the second currents, selecting the first transistor with a channel width-to-channel length ratio can also adjust the sum of the second currents.

[0015] In one possible implementation, the output of a second current is controlled by the light emission status information of each of the multiple current source branches.

[0016] For example, the light emission state information includes at least one of the light emission intensity information of multiple pixel units and the light emission quantity information of multiple pixel units.

[0017] In this embodiment, when the light emission state information includes light emission intensity information, the magnitude of the first current flowing through the pixel unit and the device parameters of the pixel unit determine the maximum light emission intensity of the pixel unit. Based on the maximum light emission intensity required by the pixel unit, the total magnitude of the second current output by the current source branch is controlled, thereby controlling the magnitude of the first current flowing through the pixel unit in the pixel branch. At this time, whether each of the multiple current source branches outputs a second current is controlled, thereby adjusting the total magnitude of the second current output by the current source branch, and adjusting the magnitude of the first current through the second current. When the light emission state information includes light emission quantity information, in this embodiment, the magnitude of the first current is determined by the second current. The more pixel units that need to emit light, the more pixel branches need to flow through the first current. The more pixel branches that need to flow through the first current, the larger the total magnitude of the second current output by the current source branch, and the faster the first current flowing through the pixel branch rises to a stable current magnitude sufficient to drive the pixel unit to emit light, i.e., the shorter the driving time. When the number of pixel branches that need to emit light is greater, in order to ensure that each emitting pixel unit can emit light normally within the specified driving time, it is necessary to control more current source branches to output more second currents, thereby increasing the total magnitude of the output second current. When the number of pixel units that need to emit light is smaller, while ensuring that each emitting pixel unit can emit light normally within the specified driving time, it is necessary to control and reduce the number of current source branches that output second currents, in order to minimize the total magnitude of the output second current.

[0018] In one possible implementation, the voltage rating of the pulse width control switch is different from that of the second transistor.

[0019] In this embodiment, the stability of the pixel branch can be improved by increasing the withstand voltage of the pulse width control switch and / or the second transistor. Withstand voltage is an inherent characteristic of transistors and is related to the proportion of epitaxial layer resistance to the total on-resistance in the transistor structure. When the proportion of epitaxial layer resistance to the total on-resistance is small, the withstand voltage will also be small. For transistors with low withstand voltage, a smaller current is required to drive the transistor. When the proportion of epitaxial layer resistance to the total on-resistance is large, the withstand voltage will also be large. For transistors with high withstand voltage, a larger current is required to drive the transistor. Withstand voltage, as a device parameter of a transistor, is used to describe the transistor's operating performance. It can be used to express the transistor's driving performance and its ability to withstand voltage differences. In practical applications, pixel units may experience voltage drops below the preset voltage due to process variations and leakage current, while the voltage difference in the circuit branches formed by a pixel branch is arranged according to the preset voltage. When the voltage across a pixel unit is lower than the preset voltage (e.g., the preset voltage difference is 2.5V, but due to process variations and leakage current, the actual voltage difference is only 1.5V or lower), the second transistor and pulse width control switch on that circuit branch need to withstand a larger voltage difference. If the voltage rating of the second transistor and pulse width control switch is low, they may be unable to withstand the larger voltage difference and become damaged, leading to stability issues. One solution is to increase the voltage rating of the second transistor and pulse width control switch. This requires larger second and first currents to quickly turn on the circuit branch and achieve a rapid response from the pixel unit within the specified driving time, which undoubtedly increases the system's power consumption significantly. Therefore, for a pixel branch, the voltage rating of one of the pulse width control switch and the second transistor can be increased to improve the stability of the pixel branch while avoiding excessive power consumption.

[0020] In one possible implementation, the pulse width control switch is coupled between the second transistor and the pixel unit.

[0021] In this embodiment, the pulse width control switch is coupled between the pixel unit and the second transistor. This allows the pulse width control switch to withstand a certain voltage across the pixel branch in the middle section, thus ensuring the stability of the pixel branch.

[0022] In one possible implementation, the withstand voltage of the pulse width control switch is greater than the supply voltage of the pixel branch.

[0023] In this embodiment, the withstand voltage of the pulse width control switch can be appropriately increased. This improves circuit stability. Specifically, setting the withstand voltage of the pulse width control switch to be greater than the supply voltage of the pixel branch significantly improves circuit stability and reduces the risk of burnout of the pulse width control switch and the second transistor. Furthermore, the pulse width control switch can be positioned between the second transistor and the pixel unit. When the voltage difference across the pixel unit is lower than a preset value, the pulse width control switch can act as a buffer, ensuring the stability of the circuit branch.

[0024] In some possible implementations, the pixel unit includes a light-emitting diode.

[0025] In this embodiment of the application, a first current is used to drive a light-emitting diode (LED) so that light is emitted through the LED.

[0026] Secondly, embodiments of this application also provide a display method based on a display circuit, the display circuit including multiple current source branches and multiple pixel branches; each of the multiple current source branches includes a control circuit and a first transistor; each control circuit is coupled to a corresponding first transistor; each of the multiple pixel branches includes a second transistor, a pulse width control switch, and a pixel unit connected in series; the second transistor is coupled to the gate of the first transistor, and the second transistor and the conducting first transistor form a current mirror; the method includes: controlling the conduction and disconnection of the corresponding pixel branch through the pulse width control switch; and controlling whether the corresponding first transistor is turned on through the control circuit according to the number of conducting pixel branches.

[0027] In this embodiment, different numbers of activated pixel branches require different magnitudes of the first current to achieve fast response of the pixel units within the pixel branches. Depending on the specific magnitude of the required first current, a corresponding number of first transistors need to be activated. These activated first and second transistors form a current mirror, thereby adjusting the current magnitude of the first circuit. This achieves fast response of the pixel units while minimizing power consumption.

[0028] In one possible implementation, the control circuit includes a first switch and a second switch; the first switch is coupled between a first electrode of a first transistor and the gate of the first transistor; the second switch is coupled between a second electrode of the first transistor and the gate of the first transistor; the method specifically includes: controlling the first switch to be turned on and the second switch to be turned off, so as to control the corresponding first transistor to be turned on; or, controlling the first switch to be turned off and the second switch to be turned on, so as to control the corresponding first transistor to be turned off.

[0029] In one possible implementation, the output of a second current is controlled by light emission state information for each of the plurality of current source branches. The light emission state information includes at least one of light emission intensity information of the plurality of pixel units and light emission quantity information of the plurality of pixel units.

[0030] In some possible implementations, for different current source branches, the ratio of the channel width to the channel length of the first transistor in the first current source branch is equal to the ratio of the channel width to the channel length of the first transistor in the second current source branch; in this method, the operation of controlling whether the corresponding first transistor is turned on by the control circuit according to the number of conducted pixel branches includes: determining a first number according to the number of conducted pixel branches; and controlling the first number of first transistors to be turned on by the control circuit.

[0031] In this embodiment, the channel width to channel length ratio of the first transistors corresponding to the multiple current source branches is equal. Therefore, in each current mirror formed by the first transistor and the second transistor, the ratio of the magnitude of the second current flowing through the first transistor to the magnitude of the first current flowing through the second transistor is also constant. At this time, it is only necessary to determine the number of first transistors that need to be turned on based on the magnitude of the first current.

[0032] In some possible implementations, for different current source branches, the ratio of the channel width to the channel length of the first transistor in the first current source branch is k times the ratio of the channel width to the channel length of the first transistor in the second current source branch; in this method, the operation of controlling whether the corresponding first transistor is turned on by the control circuit according to the number of conducted pixel branches includes: determining a first ratio based on the number of conducted pixel branches, the first ratio being the ratio of the channel width to the channel length of at least one first transistor; and controlling at least one first transistor corresponding to the first ratio to be turned on by the control circuit.

[0033] In this embodiment, the channel width to channel length ratio between two different first transistors may be equal or unequal. In this case, for a current mirror formed by a first transistor and a second transistor with different channel width to channel length ratios, the magnitude of the first current flowing through the second transistor will also be different. Therefore, a first ratio is determined based on the required magnitude of the first current. This first ratio can indicate the channel width to channel length ratio of a particular first transistor, and then the corresponding first current is obtained by turning on that particular first transistor. Alternatively, the first ratio can indicate the channel width to channel length ratio of multiple first transistors, and then the corresponding first current is obtained by turning on all of the multiple first transistors.

[0034] In some possible implementations, the method further includes: controlling the pulse width control switch to turn on and off via a pulse width modulation signal; when the pulse width modulation signal is at a first level, controlling the pulse width control switch to turn on to control the conduction of the corresponding pixel branch; when the pulse width modulation signal is at a second level, controlling the pulse width control switch to turn off to control the disconnection of the corresponding pixel branch.

[0035] In some possible implementations, the method further includes controlling the display brightness of the pixel unit using pulse width modulation signals with different duty cycles.

[0036] In this embodiment, taking an N-type metal-oxide-semiconductor (NMOS) transistor as an example, when the pulse width modulation signal is a high-level signal, the pulse width control switch is turned on, and the light-emitting diode (LED) emits light. Simultaneously, the duty cycle (i.e., the percentage of the effective pulse width) of the high-level pulse width modulation signal can adjust the luminous intensity of the LED. When the pulse width modulation signal is a low-level signal, the pulse width control switch is not turned on, and the LED does not emit light.

[0037] Thirdly, embodiments of this application also provide a display device, including a display circuit as described in the first aspect above; the display circuit is used to emit light to display an image.

[0038] Fourthly, embodiments of this application also provide an electronic device, which includes a display device as described in the third aspect above, the display device being used to emit light to display an image.

[0039] Fifthly, embodiments of this application also provide a chip system including at least one processor and at least one interface circuit. The at least one processor and at least one interface circuit are interconnected via lines. The processor is used to support the chip system in implementing various functions or steps in the display method described in the second aspect above, and the at least one interface circuit is used to receive signals from other devices (e.g., memory) or to send signals to other devices (e.g., a communication interface). The chip system may include a chip and may also include other discrete devices.

[0040] Sixthly, embodiments of this application also provide a computer-readable storage medium including instructions that, when executed on the aforementioned display device, chip system, or electronic device, cause the display device, chip system, or electronic device to perform various functions or steps in the display method described in the second aspect.

[0041] In a seventh aspect, embodiments of this application also provide a computer program product including instructions that, when executed on the aforementioned display device, chip system, or electronic device, cause the display device, chip system, or electronic device to perform various functions or steps in the display method described in the second aspect.

[0042] For the technical effects of the second, third, fourth, fifth, sixth, and seventh aspects, please refer to the relevant description of the technical effects of the first aspect above. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application;

[0044] Figure 2 This is a schematic diagram of the structure of a display device provided in an embodiment of this application;

[0045] Figure 3 This is a schematic diagram of a display circuit provided in an embodiment of this application;

[0046] Figure 4 This application provides a schematic diagram of the structure of a current source branch and a pixel branch in an embodiment of the present application.

[0047] Figure 5 A schematic diagram of another current source branch and pixel branch provided in the embodiments of this application;

[0048] Figure 6 A schematic diagram of another current source branch and pixel branch provided in the embodiments of this application;

[0049] Figure 7 A schematic diagram of another current source branch and pixel branch provided in the embodiments of this application;

[0050] Figure 8 A schematic diagram of another current source branch and pixel branch provided in the embodiments of this application;

[0051] Figure 9 A schematic diagram of another current source branch and pixel branch provided in the embodiments of this application;

[0052] Figure 10 This is a schematic diagram of a pixel branch structure provided in an embodiment of this application;

[0053] Figure 11 This is a schematic diagram of another pixel branch structure provided in an embodiment of this application;

[0054] Figure 12 This is a schematic diagram of another display circuit provided in an embodiment of this application;

[0055] Figure 13 This is a schematic diagram of another display circuit provided in an embodiment of this application;

[0056] Figure 14 A schematic flowchart illustrating a display method provided in an embodiment of this application;

[0057] Figure 15 A schematic diagram of a light-emitting diode matrix provided in an embodiment of this application;

[0058] Figure 16 A timing diagram of a pulse width modulation signal and a first current when the ratio of the sum of the second current to the sum of the first current is 1:100, provided for an embodiment of this application;

[0059] Figure 17 A timing diagram of a pulse width modulation signal and a first current when the ratio of the sum of the second current to the sum of the first current is 10:100, provided for an embodiment of this application;

[0060] Figure 18 This application provides a schematic diagram of the structure of a chip system. Detailed Implementation

[0061] It should be noted that the terms "first" and "second" used in the embodiments of this application are only used to distinguish features of the same type and should not be construed as indicating relative importance, quantity, order, etc.

[0062] The terms "exemplary" or "for example" used in the embodiments of this application are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0063] The terms "coupling" and "connection" used in the embodiments of this application should be interpreted broadly. For example, they can refer to a physical direct connection or an indirect connection achieved through electronic devices, such as a connection achieved through resistors, inductors, capacitors or other electronic devices.

[0064] First, some basic concepts involved in the embodiments of this application will be explained:

[0065] A light-emitting diode (LED) is a compound containing gallium (Ga), arsenic (As), phosphorus (P), and nitrogen (N). It is manufactured based on the principle that electrons and holes recombine to emit visible light. Gallium arsenide LEDs emit red light, gallium phosphide LEDs emit green light, silicon carbide LEDs emit yellow light, and gallium nitride LEDs emit blue light. LEDs were initially used for indicator lighting in instruments, then expanded to traffic lights, landscape lighting, automotive lighting, and mobile phone keypads and backlights. Later, a new technology, micro light-emitting diodes (MLEDs), was developed, which significantly reduced the size of traditional LEDs. These independently emitting red, blue, and green microLEDs are arranged in arrays to form display arrays and are applied in the display technology field. MicroLEDs have self-emissive display characteristics. Compared to organic light-emitting diodes (OLEDs), which are also self-emissive, microLEDs are more efficient, have a longer lifespan, and their materials are less affected by environmental factors, making them more stable.

[0066] Like ordinary diodes, light-emitting diodes (LEDs) consist of a PN junction and exhibit unidirectional conductivity. The core of an LED is a wafer composed of P-type and N-type semiconductors, with a transition layer between them called the PN junction. In the PN junction of certain semiconductor materials, injected minority carriers recombine with majority carriers, releasing excess energy as light, thus directly converting electrical energy into light energy. When a reverse voltage is applied to the PN junction, minority carriers are difficult to inject, so no light is emitted. When a forward voltage is applied to the LED, holes injected from the P-region into the N-region and electrons injected from the N-region into the P-region recombine with electrons in the N-region and holes in the P-region within a few micrometers of the PN junction, producing spontaneous fluorescence. The energy states of electrons and holes differ in different semiconductor materials. The amount of energy released when electrons and holes recombine varies; the more energy released, the shorter the wavelength of the emitted light. Commonly used LEDs emit red, green, or yellow light. When it is in the forward operating state (i.e., a forward voltage is applied across its terminals), as current flows from the LED anode to the cathode, the semiconductor crystal emits light of different colors from ultraviolet to infrared, and the intensity of the light is related to the current.

[0067] One common driving method for LEDs is current driving. Current driving involves providing a constant driving current to the LED, meaning the current magnitude is fixed, and then using pulse width modulation (PWM) to adjust the proportion of time the LED's branch is on. The time required for the LED to light up normally after providing the driving current is called the driving time. The driving time is affected by factors such as load size and driving current magnitude. For LEDs of the same specifications, a larger driving current results in a shorter driving time than a smaller driving current. Each display has a fixed refresh rate and resolution. These fixed refresh rates and resolutions correspond to specified driving times. If the provided driving current is too small, the driving time of the corresponding LED may exceed the specified driving time, causing abnormal display functionality. This problem is particularly pronounced in displays using miniature LEDs.

[0068] One current-driven implementation involves providing a constant reference current, generating multiple constant drive currents based on this reference current, and outputting them to LEDs on corresponding branches. Then, pulse width modulation (PWM) is used to adjust the conduction time of each branch to control whether the LEDs on that branch emit light and their light intensity. In this approach, when a large number of branches are active, a large reference current is required to ensure a fast response within the specified drive time using PWM. However, when no branches need to be active, the constant reference current leads to wasted power consumption; conversely, when only a few branches need to be active, providing a large reference current also results in wasted power consumption.

[0069] To reduce power consumption, embodiments of this application provide an electronic device, such as... Figure 1 As shown, the electronic device 1 includes a display device 2, which receives data signals and emits light according to the data signals to display corresponding images. Figure 2 As shown, the display device 2 includes a display circuit 3. (As indicated...) Figure 3 As shown, the display circuit 3 includes a processor 31, a current source module 32, and multiple pixel branches 33. The current source module 32 includes multiple current source branches 321. Figure 4As shown, each current source branch 321 includes a first transistor 3211. Each pixel branch 33 includes a pixel unit 333 for emitting light, a second transistor 331, and a pulse width control switch 332. The pixel unit 333, the second transistor 331, and the pulse width control switch 332 are connected in series. The gates of multiple first transistors 3211 and multiple second transistors 331 are coupled together to a first coupling point 34 to form a current mirror (CM) structure; each current source branch 321 is used to carry a second current; the pixel branch 33 is used to make each pixel unit 333 carry a first current to drive the pixel unit 333 to emit light; the total current of all the second currents output by the current source module 32 is used to determine the current magnitude of the first current; the processor 31 is coupled to the multiple current source branches 321; the processor 31 is used to: control the conduction or cutoff of each current source branch 321 in the multiple current source branches 321 through the control circuit, so as to control whether each current source branch 321 outputs a second current, thereby adjusting the total current magnitude of the second current output by the current source module 32.

[0070] In some possible implementations, the electronic device 1 can be a mobile phone, desktop computer, laptop computer, tablet computer, watch, audio-visual playback device, virtual reality (VR) display device, augmented reality (AR) display device, wearable display device, etc.

[0071] In this embodiment, each of the first transistors 3211 in the multiple current source branches 321 forms a current mirror structure with the second transistors 331 in the pixel branch 33. Therefore, by controlling the number of current source branches 321 that are turned on, the total magnitude of the second current output by the current source module 32 can be adjusted, and the magnitude of the first current flowing through the pixel branch 33 is determined by the magnitude of the total second current. The first current flowing through the pixel branch 33 is output as a driving current to the pixel unit 333 to drive the pixel unit 333 to emit light. Under normal circumstances, the second current, as a reference current that determines the magnitude of the first current, is always present. When the pixel unit 333 does not need to emit light, the pixel branch 33 does not need to flow with the first current, but the current source module 32 is still outputting the second current as a reference current, which will result in wasted power consumption. At the same time, when multiple pixel units 333 are set, the more pixel units 333 there are, the more corresponding pixel branches 33 there are, and a larger first current is required to meet the fast response driving of the pixel unit 333. To ensure that the first current can meet the requirement of simultaneous illumination of all pixel units 333 in multiple pixel branches 33 and still respond quickly within the specified driving time, the first current needs to be set as large as possible. Therefore, the total magnitude of the second current output by the current source module 32 also needs to be set as large as possible. However, if only some pixel units 333 in the multiple pixel branches 33 need to illuminate, while a larger first and second current can meet the requirement of rapid response for those pixel units 333 within the specified driving time, it will still result in some wasted power. To avoid this wasted power, such as... Figure 3 , Figure 4 As shown in this embodiment, a plurality of current source branches 321 are provided in the current source module 32, each current source branch 321 being used to output a second current. A control circuit is used to adjust whether each of the plurality of current source branches 321 outputs a second current, thereby dynamically adjusting the total magnitude of the second current output by the current source module 32. Furthermore, the magnitude of the first current is adjusted based on the total magnitude of the second current.

[0072] In some possible implementations, the processor 31 adjusts whether each of the plurality of current source branches 321 is turned on based on the light emission state information. The light emission state information includes at least one of the light emission intensity information of the plurality of pixel units 333 and the light emission quantity information of the plurality of pixel units 333.

[0073] For example, when the light emission state information includes light emission intensity information, the magnitude of the first current flowing through the pixel unit 333 and the device parameters of the pixel unit 333 determine the maximum light emission intensity of the pixel unit 333. The processor 31 controls the total magnitude of the second current output by the current source module 32 according to the maximum light emission intensity required by the pixel unit 333, thereby controlling the magnitude of the corresponding first current provided by the pixel branch 33. At this time, it controls whether each of the multiple current source branches 321 outputs a second current, thereby adjusting the total magnitude of the second current output by the current source module 32, so as to adjust the magnitude of the first current through the second current.

[0074] For example, when the light emission state information includes light emission quantity information. In this embodiment, the magnitude of the first current is determined by the second current. The more pixel units 333 that need to emit light, the more pixel branches 33 provide the first current. When the number of pixel units 333 is large, the total magnitude of the second current output by the current source module 32 is larger, and the first current flowing through the pixel branch 33 rises faster to a stable current magnitude sufficient to drive the pixel unit 333 to emit light, i.e., the driving time is shorter. When the number of pixel units 333 that need to emit light is large, in order to ensure that each emitting pixel unit 333 can emit light normally within the specified driving time, the processor 31 needs to control more current source branches 321 to output more second currents to increase the total magnitude of the output second current. When the number of pixel units 333 that need to emit light is small, while ensuring that each emitting pixel unit 333 can emit light normally within the specified driving time, the processor 31 needs to control and reduce the number of current source branches 321 that output the second current to minimize the total magnitude of the output second current.

[0075] In some possible implementations, such as Figure 4 As shown, a current source branch 321 includes a first transistor 3211 and a control circuit; the control circuit includes a first switch 3213 and a second switch 3214; a pixel branch 33 includes a second transistor 331. The first switch 3213 is coupled between the first terminal of the first transistor 3211 and the gate of the first transistor 3211; the second switch 3214 is coupled between the second terminal of the first transistor 3211 and the gate of the first transistor 3211; the gate of the first transistor 3211 and the gate of the second transistor 331 are coupled to a first coupling point 34; the processor 31 is specifically used to: control the first switch 3213 to be turned on and the second switch 3214 to be turned off, so as to control the corresponding first transistor 3211 to be turned on; or, control the first switch 3213 to be turned off and the second switch 3214 to be turned on, so as to control the corresponding first transistor 3211 to be turned off.

[0076] For example, such as Figure 5 As shown, the first transistor 3211 and the second transistor 331 can be N-type metal-oxide-semiconductor (NMOS) transistors.

[0077] For example, such as Figure 6 As shown, the first transistor 3211 and the second transistor 331 can be P-type metal-oxide-semiconductor (PMOS) transistors.

[0078] In this embodiment, when the gate of the first transistor 3211 is coupled to the gate of the second transistor 331, the gate voltage of the first transistor 3211 is equal to the gate voltage of the second transistor 331. When the second terminal of the first transistor 3211 is coupled to the gate of the first transistor 3211, the first transistor 3211 is in a turned-off state. At this time, the first terminal of the first transistor 3211 will not output a second current, and the magnitude of the second current output by multiple first transistors 3211 will be reduced. When the first terminal of a certain first transistor 3211 is coupled to the gate of the first transistor 3211, the first transistor 3211 is turned on, and the first and second terminals of the first transistor 3211 are connected and a second current flows through them. The first transistor 3211 and the second transistor 331 form a current mirror (CM) structure. For multiple current source branches 321, all conducting first transistors 3211 in the multiple current source branches 321 form a current mirror structure with the second transistor 331, and the sum of the multiple second currents output by all conducting first transistors 3211 is used as the reference current. The first current flowing through the second transistor 331 after it is turned on is proportional to the total current of all second currents. According to the characteristics of the current mirror, this proportional relationship is determined by the proportional relationship between the first ratio and the second ratio. The first ratio is the ratio of the channel width W1 of the first transistor 3211 to the channel length L1, W1 / L1, and the second ratio is the ratio of the channel width W2 of the second transistor 331 to the channel length L2, W2 / L2.

[0079] In some possible implementations, such as Figure 5 , Figure 6 As shown, the current source branch 321 also includes a constant current source 3212. The constant current source 3212 is used to provide a second current to the first transistor 3211.

[0080] For example, the constant current source 3212 includes a current source 32121.

[0081] In this embodiment of the application, a constant second current is provided as a reference current through current source 32121.

[0082] For example, such as Figure 7 , Figure 8 As shown, the constant current source 3212 also includes a reference current mirror unit 32122.

[0083] In this embodiment, the first transistor 3211 and the second transistor 331 may have certain accuracy errors due to manufacturing processes and other reasons. In this case, a constant current is provided to the reference side of the reference current mirror unit 32122 through the current source 32121, and a constant reference current is output from the output side of the reference current mirror unit 32122. This constant reference current is then provided to the first transistor 3211 as a second current and output from the first transistor 3211 to improve the accuracy of the second current and the first current. Similarly, depending on the accuracy requirements, an additional reference current mirror unit 32122 can be added to the reference side or the output side of the reference current mirror unit 32122 for further calibration. Figure 7 and Figure 8 Corresponding to each as follows Figure 5 and Figure 6 The specific application of the 3212 constant current source in the upper structure.

[0084] In some possible implementations, such as Figure 9 As shown, a current source branch 321 includes multiple first transistors 3211 connected in series, and a pixel branch 33 includes a number of second transistors 331 connected in series with a number corresponding to the first transistors 3211. The gate of one first transistor 3211 is coupled to the gate of one second transistor 331 to form a current mirror structure. Among the multiple current mirrors, the ratio of a first ratio to a second ratio is equal. The first ratio is the ratio of the channel width to the channel length of the first transistor 3211 in the current mirror, and the second ratio is the ratio of the channel width to the channel length of the second transistor 331 in the current mirror.

[0085] In some possible implementations, such as Figure 10 As shown, pixel unit 333 includes at least one light-emitting diode 3331.

[0086] For example, the light-emitting diode 3331 can be a regular light-emitting diode (LED) or a micro light-emitting diode (MLED).

[0087] In some possible implementations, such as Figure 11As shown, pixel branch 33 also includes a pulse width control switch 332. Processor 31 outputs a pulse width modulation signal to the pulse width control switch 332. This pulse width modulation signal is used to turn on the pulse width control switch 332, thereby turning on the path of the light-emitting diode 3331 to control the light-emitting diode 3331 to emit light; or the pulse width modulation signal is used to turn off the pulse width control switch 332, thereby turning off the path of the light-emitting diode 3331 to control the light-emitting diode 3331 to not emit light. Simultaneously, different duty cycles of the pulse width modulation signal are used to control the luminous intensity of the corresponding light-emitting diode 3331.

[0088] For example, taking the pulse width control switch 332 as an NMOS transistor, when the pulse width modulation signal is a high-level signal, the pulse width control switch 332 is turned on, and the light-emitting diode 3331 emits light. Simultaneously, the duty cycle (i.e., the percentage of the effective pulse width) of the high-level pulse width modulation signal can adjust the luminous intensity of the light-emitting diode 3331. When the pulse width modulation signal is a low-level signal, the pulse width control switch 332 is not turned on, and the light-emitting diode 3331 does not emit light.

[0089] For example, the pulse width control switch 332 can be connected in series at any position on the circuit branch formed by the pixel branch 33.

[0090] For example, the pulse width control switch 332 can be a transistor, a triode, or other switching device controlled by high and low levels.

[0091] In this embodiment, the function of the pulse width control switch 332 is to control the conduction of the circuit branch formed by the pixel branch 33 and to control the conduction frequency to adjust the light emission intensity. Therefore, this function can be achieved as long as the pulse width control switch 332 is placed on the circuit branch and can be used to control the conduction and cutoff of the circuit branch.

[0092] For example, the pulse width control switch 332 is disposed between the light-emitting diode 3331 and the second transistor 331.

[0093] Optionally, the voltage rating of the second transistor 331 can be equal to, or greater than or less than, the voltage rating of the pulse width control switch 332.

[0094] For example, such as Figure 12As shown, taking a configuration of 60 pixel branches 33 as an example, each pixel branch 33 includes a second transistor 331, a light-emitting diode 3331, and a pulse width control switch 332. Correspondingly, three current source branches 321 can be configured, each current source branch 321 including a first transistor 3211, a first switch 3213, and a second switch 3214. Each light-emitting diode 3331 is coupled to a corresponding second transistor 331 in one pixel branch 33. By adjusting the ratio W1 / L1 of the channel width W1 to the channel length L1 of the corresponding first transistor 3211 in the three current source branches 321, when the first current value is lref, the second current values ​​output by the three current source branches 321 are lref, 2lref, and 3lref, respectively. When none of the 60 LEDs 3331 need to emit light, the first switch 3213 corresponding to the three first transistors 3211 is turned off, and the second switch 3214 is turned on, causing all three first transistors 3211 to be off, resulting in no second current output. When 1-10 LEDs 3331 need to emit light, the first transistor 3211 corresponding to the second current of magnitude lref is turned on, while the other two first transistors 3211 are turned off, making the total output second current of lref sufficient for 1-10 LEDs 3331 to emit light. Similarly, when 11-20, 21-30, 31-40, 41-50, and 51-60 LEDs 3331 need to emit light, the on / off state of the three first transistors 3211 can be controlled accordingly to adjust the total second current to meet the emission requirements of the corresponding number of LEDs 3331.

[0095] In this embodiment, the withstand voltage is an inherent characteristic of the transistor, related to the proportion of the epitaxial layer resistance to the total on-resistance in the transistor structure. When the proportion of the epitaxial layer resistance to the total on-resistance is small, the withstand voltage will also be small. For transistors with low withstand voltage, a smaller current is required to drive the transistor. When the proportion of the epitaxial layer resistance to the total on-resistance is large, the withstand voltage will also be large. For transistors with high withstand voltage, a larger current is required to drive the transistor. The withstand voltage, as a device parameter of the transistor, is used to describe the transistor's operating performance. It can be used to express the transistor's driving performance and its ability to withstand voltage differences, etc. In practical applications, the voltage across the LED 3331 may be lower than the actual preset voltage due to process deviations and leakage current, while the voltage difference in the circuit branch consisting of a pixel branch 33 and a pixel unit 333 has been arranged according to the preset voltage. When the voltage across LED 3331 is lower than the preset voltage (e.g., the preset voltage difference is 2.5V, but due to manufacturing variations and leakage current, the actual voltage difference is only 1.5V or lower), the second transistor 331 and pulse width control (PWM) switch 332 in this circuit branch need to withstand a larger voltage difference. If their voltage ratings are low, they may be unable to withstand the larger voltage difference and become damaged, leading to stability issues. One solution is to increase the voltage ratings of the second transistor 331 and PWM switch 332. This requires larger second and first currents to quickly turn on the circuit branch and achieve a rapid response from LED 3331 within the specified drive time, which undoubtedly increases system power consumption significantly. In this case, the voltage rating of PWM switch 332 can be appropriately increased to improve circuit stability. Meanwhile, the pulse width control switch 332 can be placed between the second transistor 331 and the light-emitting diode 3331. When the voltage difference across the light-emitting diode 3331 is lower than the preset condition, the pulse width control switch 332 can play a good buffering role to ensure the stability of the circuit branch.

[0096] In some possible implementations, such as Figure 13 As shown, the display circuit 3 also includes a digital front-end circuit 35, which is coupled to the processor 31. The processor 31 is used to control the digital front-end circuit 35 to output a pulse width modulation signal to the corresponding pulse width control switch 332 according to the digital signal.

[0097] Based on including Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8, Figure 9 , Figure 10 , Figure 11 , Figure 12 , Figure 13 The display circuit 3 shown in the diagram can be used to perform, for example... Figure 14 The display method shown includes steps S110-S120:

[0098] Step S110: Obtain light emission state information, which is used to indicate at least one of the light emission intensity information of the plurality of pixel units 333 and the light emission quantity information of the plurality of pixel units 333.

[0099] Step S120: Based on the light emission status information, control the current source branch in the current source module 32 to turn on and off, so as to control the magnitude of the current flowing through the pixel branch 33.

[0100] In this embodiment, when the processor 31 receives a light emission status signal, if the light emission status signal indicates the specific light emission intensity required by the pixel unit 333, then according to the first current required for the light emission intensity, the current source module 32 is controlled to output a second current whose total current is proportional to the first current. If the light emission status signal indicates the specific number of pixel units 333 that need to emit light, then according to the specific number of light emission, the number of current paths provided is the number of second currents that satisfy the pixel unit 333's rapid response to light emission within the driving time.

[0101] In some possible implementations, such as Figure 4 As shown, a current source branch 321 includes a first transistor 3211 and a control circuit; the control circuit includes a first switch 3213 and a second switch 3214; a pixel branch 33 includes a second transistor 331. The first switch 3213 is coupled between the first terminal of the first transistor 3211 and the gate of the first transistor 3211; the second switch 3214 is coupled between the second terminal of the first transistor 3211 and the gate of the first transistor 3211; the gate of the first transistor 3211 and the gate of the second transistor 331 are coupled to a first coupling point 34; the processor 31 is specifically used to: control the first switch 3213 to be turned on and the second switch 3214 to be turned off, so as to control the corresponding first transistor 3211 to be turned on; or, control the first switch 3213 to be turned off and the second switch 3214 to be turned on, so as to control the corresponding first transistor 3211 to be turned off.

[0102] For example, such as Figure 5As shown, the first transistor 3211 and the second transistor 331 can be NMOS transistors. In this case, the first terminal of the first transistor 3211 is the drain, and the second terminal is the source. The first terminal of the second transistor 331 is the drain and coupled to the pixel unit 333. The first terminal of the first transistor 3211 is used to input the second current. When the first switch 3213 is turned on and the second switch 3214 is turned off, so that the first terminal of the first transistor 3211 is coupled to the gate (i.e., when the drain and gate of the first transistor 3211 are coupled), since the first transistor 3211 and the second transistor 331 are NMOS transistors, they conduct when the gate is at a high level. At this time, the second terminal (i.e., the source) of the first transistor 3211 is grounded or at a low level, and the first terminal (i.e., the drain) of the first transistor 3211 is at a high level. Therefore, the high level of the first terminal of the first transistor 3211 causes the first transistor 3211 and the second transistor 331 to conduct, thereby allowing the second current to flow between the second terminal and the first terminal of the first transistor 3211. Because the gates of the first transistor 3211 and the second transistor 331 are coupled, when the second current passes through the first transistor 3211, the second transistor 331 also conducts and the first current flows through it. The conduction of the second transistor 331 causes the first current to flow through the pixel unit 333, which drives the pixel unit 333 to emit light. Due to the structural characteristics of the current mirror, the magnitude of the second current is proportional to the magnitude of the first current. This proportional relationship is determined by the ratio between a first ratio and a second ratio. The first ratio is the ratio of the channel width W1 of the first transistor 3211 to the channel length L1, W1 / L1, and the second ratio is the ratio of the channel width W2 of the second transistor 331 to the channel length L2, W2 / L2. When the second switch 3214 is turned on and the first switch 3213 is turned off so that the second terminal of the first transistor 3211 is coupled to the gate (i.e., when the source of the first transistor 3211 is coupled to the gate), since the first transistor 3211 is an NMOS transistor, the gate-source voltage VGS of the first transistor 3211 is 0. At this time, the first transistor 3211 does not form a current mirror structure with the second transistor 331, and the turned-off first transistor 3211 can be regarded as not coupled at the first coupling point 34.

[0103] For example, such as Figure 6As shown, the first transistor 3211 and the second transistor 331 can be PMOS transistors. In this case, the first terminal of the first transistor 3211 is the drain, and the second terminal is the source. The first terminal of the second transistor 331 is the drain and coupled to the pixel unit 333. The first terminal of the first transistor 3211 is used to output the second current. When the first switch 3213 is turned on and the second switch 3214 is turned off, so that the first terminal of the first transistor 3211 is coupled to the gate (i.e., when the drain and gate of the first transistor 3211 are coupled), since the first transistor 3211 and the second transistor 331 are PMOS transistors, they are turned on by a low level. At this time, the first terminal (i.e., the drain) of the first transistor 3211 is grounded or connected to a low level, and the second terminal (i.e., the source) of the first transistor 3211 is connected to a high level. Therefore, the low level at the first terminal of the first transistor 3211 causes the first transistor 3211 and the second transistor 331 to conduct, thereby allowing the second current to flow from the second terminal of the first transistor 3211 through the first terminal of the first transistor 3211 and output from the first terminal of the first transistor 3211. Because the gates of the first transistor 3211 and the second transistor 331 are coupled, when the second current passes through the first transistor 3211, the second transistor 331 also conducts and the first current flows through it. The conduction of the second transistor 331 causes the first current to flow through the pixel unit 333, which drives the pixel unit 333 to emit light. Due to the structural characteristics of the current mirror, the magnitude of the second current is proportional to the magnitude of the first current. This proportional relationship is determined by the ratio between a first ratio and a second ratio. The first ratio is the ratio of the channel width W1 of the first transistor 3211 to the channel length L1, W1 / L1, and the second ratio is the ratio of the channel width W2 of the second transistor 331 to the channel length L2, W2 / L2. When the first switch 3213 is turned off and the second switch 3214 is turned on so that the second terminal of the first transistor 3211 is coupled to the gate (i.e., when the source of the first transistor 3211 is coupled to the gate), the gate-source voltage VGS of the first transistor 3211 is 0. At this time, the first transistor 3211 does not form a current mirror structure with the second transistor 331, and the turned-off first transistor 3211 can be regarded as not coupled at the first coupling point 34.

[0104] For example, for each first transistor 3211, the gate of the first transistor 3211 is connected to the first terminal of the first transistor 3211 or the gate of the first transistor 3211 is connected to the second terminal of the first transistor 3211 by the first switch 3213 and the second switch 3214.

[0105] In this embodiment, the conduction mode of a first transistor 3211 can be controlled by a digital signal. For example, when the value of the digital signal is 0, the first switch 3213 between the first electrode and the gate of the first transistor 3211 is turned on, and the second switch 3214 between the second electrode and the gate of the first transistor 3211 is turned off. Conversely, when the value of the digital signal is 1, the first switch 3213 between the first electrode and the gate of the first transistor 3211 is turned off, and the second switch 3214 between the second electrode and the gate of the first transistor 3211 is turned on.

[0106] In some possible implementations, such as Figure 5 , Figure 6 As shown, the current source branch 321 also includes a constant current source 3212. The constant current source 3212 is used to provide a second current to the first transistor 3211.

[0107] For example, the constant current source 3212 includes a current source 32121.

[0108] In this embodiment, a constant second current is generated through the current source branch 321.

[0109] For example, such as Figure 7 , Figure 8 As shown, the constant current source 3212 also includes a reference current mirror unit 32122.

[0110] like Figure 7 As shown, when the first transistor 3211 and the second transistor 331 are as follows Figure 5 When using the NMOS transistor shown, the reference current mirror unit 32122 can be composed of two PMOS transistors. A constant current source 3212 is coupled to the reference side of the reference current mirror unit 32122. When the PMOS transistor on the reference side of the reference current mirror unit 32122 is turned on and a constant current flows through it, a reference current proportional to this constant current is also output from the output side of the reference current mirror unit 32122. Specifically, the ratio is the ratio of the channel width to the channel length of each of the two PMOS transistors. For example, if the ratio of the channel width to the channel length of the transistor on the reference side is A, and the ratio of the channel width to the channel length of the transistor on the output side is B, then the ratio of the magnitude of the constant current on the reference side to the magnitude of the reference current on the output side is A / B. This reference current is then input to the first NMOS transistor 3211 as a second current, and based on this second current, a first current flows through the second NMOS transistor 331, causing the pixel unit 333 to emit light.

[0111] In this embodiment, the first transistor 3211 and the second transistor 331 may have certain accuracy errors due to manufacturing processes and other reasons. In this case, a constant current is provided to the input side of the reference current mirror unit 32122 through the constant current source 3212, and a constant reference current is output from the output side of the reference current mirror unit 32122. This constant reference current is provided to the first transistor 3211 as a second current to improve the accuracy of the ratio between the total magnitude of the second current and the magnitude of the first current. Similarly, depending on the accuracy requirements, an additional reference current mirror unit 32122 can be added to the reference side or output side of the reference current mirror unit 32122 for further calibration. Figure 7 and Figure 8 Corresponding to Figure 5 and Figure 6 The specific extension of the constant current source 3212 in the upper structure.

[0112] For example, the current source module 32 includes multiple current source branches 321, each of which includes a first transistor 3211. The conducting first transistor 3211 and all the second transistors 331 constitute a current mirror.

[0113] In some possible implementations, such as Figure 9 As shown, a current source branch 321 includes multiple first transistors 3211 connected in series, and a pixel branch 33 includes a number of second transistors connected in series with a number corresponding to the number of first transistors 3211. The gate of one first transistor 3211 is coupled to the gate of one second transistor 331 to form a current mirror structure. Among the multiple current mirrors, the ratio of a first ratio to a second ratio is equal. The first ratio is the ratio of the channel width to the channel length of the first transistor 3211 in the current mirror, and the second ratio is the ratio of the channel width to the channel length of the second transistor 331 in the current mirror.

[0114] In the embodiments of this application, such as Figure 9 As shown, between each current source branch 321 and pixel branch 33, multiple current mirrors are formed by setting multiple first transistors 3211 and multiple second transistors 331 to determine the magnitude of the first current through the second current. Compared with the scheme of setting one current mirror between each current source branch 321 and pixel branch 33, this embodiment increases the accuracy of the ratio between the second current and the first current.

[0115] In some possible implementations, such as Figure 10 As shown, pixel unit 333 includes at least one light-emitting diode 3331.

[0116] In some possible implementations, such as Figure 11As shown, pixel branch 33 also includes a pulse width control switch 332. Processor 31 outputs a pulse width modulation signal to the pulse width control switch 332, which is used to turn on the pulse width control switch 332, thereby turning on the path containing the light-emitting diode 3331, causing the light-emitting diode 3331 to emit light. Simultaneously, different duty cycles of the pulse width modulation signal are used to control the luminous intensity of the corresponding light-emitting diode 3331.

[0117] For example, such as Figure 15 As shown, the light-emitting diodes 3331 in the multiple pixel units 333 constitute a light-emitting diode matrix. The light-emitting diodes 3331 in the multiple pixel units 333 can be in the same row or column of the light-emitting diode matrix, or they can be located in any different rows and / or different columns of the light-emitting diode matrix.

[0118] In this embodiment, the magnitude of the first current and the device parameters of the LED 3331 determine the maximum luminous intensity of the LED 3331 in the pixel unit 333. Whether the LED 3331 emits light is determined by the pulse width modulation signal. When no pulse width modulation signal is output to the pulse width control switch 332 or when the output is a low-level signal (i.e., a pulse width modulation signal with a duty cycle of 0), the pulse width control switch 332 is turned off, thus preventing the pixel unit 333 from emitting light. When a pulse width modulation signal with a duty cycle greater than 0 is output to the pulse width control switch 332, the pulse width control switch 332 is turned on. The duty cycle represents the proportion of high-level signals in the pulse width modulation signal. A higher duty cycle means a higher conduction frequency of the pulse width control switch 332 per unit time, and the luminous intensity of the LED 3331 is closer to its maximum luminous intensity. Therefore, by adjusting the duty cycle of the pulse width modulation signal, the luminous intensity of the LED 3331 can also be adjusted.

[0119] For example, such as Figure 16 and Figure 17 As shown, Figure 16This is a timing diagram of the pulse width modulation signal and the current signal on pixel unit 333 when the ratio of the sum of all second currents to the sum of all first currents is 1:100. It can be seen that, assuming there are 100 pixel units 333, and all 100 pixel units 333 require the first current to emit light, due to the equivalent resistive load and parasitic capacitive load on the pixel branch 33, the first current flowing in during the first few cycles of the processor 31 outputting the pulse width modulation signal is consumed by the equivalent resistive load and parasitic capacitive load, and does not reach the level that makes the light-emitting diode 3331 emit light. After several cycles (i.e., after a certain driving time), at time t0, the current on the light-emitting diode 3331 tends to stabilize, reaching the level that allows the light-emitting diode 3331 to emit light normally. When the number of pixel units 333 that need to emit light is large, there is a situation where the total current of all second currents is small, causing the driving time to exceed the specified driving time, resulting in the display device 2 failing to display normally. Therefore, the total current of the second current can be appropriately increased, for example, by ten times. like Figure 17 As shown, when the ratio of the sum of all second currents to the sum of all first currents is 10:100, that is, when 100 pixel units 333 need to emit light, and the total current of the second current is increased tenfold, at this time, although the pixel branch 33 has an equivalent resistive load and a parasitic capacitive load, it can still make the first current quickly reach a stable state that allows the light-emitting diode 3331 to emit light normally within the initial period of the pulse width modulation signal.

[0120] In this embodiment, the processor 31 determines the number of pixel units 333 that need to emit light based on the light emission status information. For example, if there are no pixel units 333 that need to emit light, the current source module 32 controls that it does not output the second current, thereby reducing power consumption. When 1-10 pixel units 333 need to emit light, the total current of the controlled second current is 1 times the reference current. 1 times the reference current can be equal to the magnitude of the first current flowing into a single second transistor 331. When 31-40 pixel units 333 need to emit light, the total current of the controlled second current is 4 times the reference current. When 91-100 pixel units 333 need to emit light, the total current of the controlled second current is 10 times the reference current.

[0121] In some possible implementations, the channel width to channel length ratio of the first transistor 3211 in each current source branch 321 is equal.

[0122] In this embodiment, for example, if the channel width to length ratio of the first transistor 3211 is equal to 1a, and the channel width to length ratio of the second transistor 331 is also 1a, then the second current output by a single first transistor 3211 is equal to the first current flowing into a single second transistor 331. The desired second current, relative to the first current, can be determined by the processor 31 controlling the conduction of a corresponding number of first transistors 3211. For example, controlling the conduction of the first transistors 3211 in five current source branches 321 will output a combined second current from five sources. In this case, the channel width to length ratio of the first transistors 3211 in the five current source branches 321 can be considered as 5a, meaning the magnitude of the second current is five times the magnitude of the first current.

[0123] In some possible implementations, the channel width to channel length ratio of the first transistor 3211 in each current source branch 321 is partially equal.

[0124] In this embodiment, for example, among different current source branches 321, the ratio of the channel width to the channel length of the first transistor 3211 in some current source branches 321 can be 1a, 4a, or 8a. By turning on one or more first transistors 3211 in different proportions, the total current of the second current can be adjusted.

[0125] In some possible implementations, the channel width to channel length ratio of the first transistor 3211 in each current source branch 321 is not equal at all.

[0126] For example, in a plurality of current source branches 321, the channel width of the first transistor 3211 in each current source branch 321 is proportional to the length width.

[0127] In this embodiment, for example, the ratio of the channel width to the channel length of the first transistor 3211 in a current source branch 321 is 1a, 2a, 4a, 8a, etc., respectively. Then, by conducting one or more first transistors 3211 with different ratios, the total current magnitude of the second current can be adjusted. When the ratios of the channel width to the channel length of the first transistors 3211 in different current source branches 321 are different but proportional, a smaller number of current source branches 321 can be used to obtain the required current magnitude for different numbers of light-emitting pixel units 333.

[0128] This application proposes a display circuit, display method, display device, and electronic device. The display circuit incorporates multiple current source branches and multiple pixel branches. Each current source branch includes a first transistor and a control circuit. Each pixel branch includes a second transistor connected in series and a pixel unit. The multiple first transistors and multiple second transistors form a current mirror structure. The control circuit controls whether each first transistor is turned on, thereby adjusting the magnitude of the current flowing through the pixel unit via the second transistor. The pixel branch carries a first current as a driving current. Each current source branch outputs a second current, and the total magnitude of all second currents determines the magnitude of the first current. This application achieves control over the magnitude of the first current by adjusting the total magnitude of the second currents output by the multiple current source branches, thereby minimizing power consumption waste caused by the first and second currents while ensuring the first current drives the pixel branch.

[0129] This application also provides a chip system, such as... Figure 18 As shown, the chip system 4 includes at least one processor 41 and at least one interface circuit 42. The at least one processor 41 and the at least one interface circuit 42 are interconnected via lines. The processor 41 is used to support the chip system in implementing the various functions or steps in the above method embodiments, and the at least one interface circuit 42 can be used to receive signals from other devices (e.g., memory) or to send signals to other devices (e.g., a communication interface). The chip system may include a chip and may also include other discrete devices.

[0130] This application also provides a computer-readable storage medium including instructions that, when executed on the aforementioned chip system or electronic device, cause the chip system or electronic device to perform various functions or steps in the above method embodiments, such as executing... Figure 14 The method shown.

[0131] This application also provides a computer program product including instructions. When the instructions are executed on the aforementioned chip system or electronic device, the chip system or electronic device causes the chip system or electronic device to perform the various functions or steps in the above method embodiments, such as executing... Figure 14 The method shown.

[0132] The processor involved in the embodiments of this application can be a chip. For example, it can be a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on chip (SoC), a central processor unit (CPU), a network processor (NP), a digital signal processor (DSP), a microcontroller unit (MCU), a programmable logic device (PLD), or other integrated chips.

[0133] The memory involved in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM). It should be noted that the memory used in the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0134] It should be understood that in the various embodiments of this application, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0135] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0136] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and modules described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0137] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or modules may be electrical, mechanical, or other forms.

[0138] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; that is, they may be located on one device or distributed across multiple devices. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0139] In addition, the functional modules in the various embodiments of this application can be integrated into one device, or each module can exist physically separately, or two or more modules can be integrated into one device.

[0140] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented using software programs, implementation can be, in whole or in part, in the form of a computer program product. This computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device containing one or more servers, data centers, etc., that can be integrated with the medium. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

[0141] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A display circuit, characterized in that, The display circuit includes multiple current source branches and multiple pixel branches; Each of the plurality of current source branches includes a control circuit and a first transistor; the control circuit includes a first switch and a second switch; the first switch is coupled between the first terminal and the gate of the first transistor; the second switch is coupled between the second terminal and the gate of the first transistor; each of the plurality of pixel branches includes a second transistor, a pulse width control switch, and a pixel unit connected in series; the second transistor is coupled to the gate of the first transistor, and the second transistor and the first transistor form a current mirror; The pulse width control switch is used to control the on and off of the corresponding pixel branch; The control circuit is used to control the on and off states of the corresponding first transistor.

2. The circuit according to claim 1, characterized in that, The voltage rating of the pulse width control switch is different from that of the second transistor.

3. The circuit according to claim 2, characterized in that, The withstand voltage of the pulse width control switch is greater than the power supply voltage of the pixel branch.

4. The circuit according to claim 3, characterized in that, The voltage rating of the pulse width control switch is greater than that of the second transistor.

5. The circuit according to claim 4, characterized in that, The pulse width control switch is coupled between the second transistor and the pixel unit.

6. The circuit according to claim 1, characterized in that, The pulse width control switch is used to input a pulse width modulation signal; when the pulse width modulation signal is at a first level, the pulse width control switch is turned on to control the conduction of the corresponding pixel branch; when the pulse width modulation signal is at a second level, the pulse width control switch is turned off to control the disconnection of the corresponding pixel branch.

7. The circuit according to claim 6, characterized in that, The pulse width modulation signal has multiple duty cycles; the pulse width modulation signal with different duty cycles is used to control different display brightness of the pixel unit.

8. The circuit according to any one of claims 1-7, characterized in that, The pixel unit is coupled to the power supply of the pixel branch by only the second transistor and the pulse width control switch.

9. The circuit according to any one of claims 1-7, characterized in that, The pixel unit is a light-emitting diode.

10. A display method, characterized in that, Based on a display circuit, the display circuit includes multiple current source branches and multiple pixel branches; each of the multiple current source branches includes a control circuit and a first transistor; the control circuit includes a first switch and a second switch; the first switch is coupled between the first terminal and the gate of the first transistor; the second switch is coupled between the second terminal and the gate of the first transistor; each of the multiple pixel branches includes a second transistor, a pulse width control switch, and a pixel unit connected in series. The second transistor is coupled to the gate of the first transistor, and the second transistor and the conducting first transistor form a current mirror; the method includes: The pulse width control switch controls the on and off of the corresponding pixel branch; The control circuit controls the on / off state of the first transistor to control the number of current source branches that are turned on, based on the number of pixel branches that are turned on.

11. The method according to claim 10, characterized in that, The step of controlling the on / off state of the corresponding pixel branch via the pulse width control switch includes: The pulse width modulation signal controls the conduction and cutoff of the pulse width control switch. When the pulse width modulation signal is at a first level, the pulse width control switch is turned on to control the conduction of the corresponding pixel branch. When the pulse width modulation signal is at a second level, the pulse width control switch is turned off to control the cutoff of the corresponding pixel branch.

12. The method according to claim 11, characterized in that, The method further includes: The different display brightness of the pixel unit is controlled by the pulse width modulation signals with different duty cycles.

13. The method according to any one of claims 10-12, characterized in that, The step of controlling whether the corresponding first transistor is turned on through the control circuit includes: The first switch is turned on and the second switch is turned off to turn on the corresponding first transistor; or, the first switch is turned off and the second switch is turned on to turn off the corresponding first transistor.

14. A display device, characterized in that, Includes a display circuit as described in any one of claims 1-9; the display circuit is used to emit light.

15. An electronic device, characterized in that, Includes the display device as described in claim 14, wherein the display device is used to emit light.

16. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes instructions that, when executed on the display device of claim 14 or the electronic device of claim 15, cause the display device or the electronic device to perform the method of any one of claims 10-13.

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