Power supply structure of screen driving circuit and screen driving circuit

Abstract

The application relates to a power supply structure of a screen driving circuit and the screen driving circuit. The power supply structure comprises: a positive voltage domain structure, which supports output of a voltage of a positive voltage domain; a negative voltage domain structure, which supports output of a voltage of a negative voltage domain, the voltage of the positive voltage domain and the voltage of the negative voltage domain having opposite polarities; and a low voltage domain structure, which supports output of a voltage of a low voltage domain. The voltage of the low voltage domain contains voltages with opposite polarities, the voltage of the low voltage domain is smaller than the voltage of the positive voltage domain, and the voltage of the low voltage domain is smaller than the voltage of the negative voltage domain. The same low voltage domain structure can output voltages with opposite polarities. Since a large distance is required between different power supply domains, the number of power supply domains is reduced, the distance between the power supply domains is relatively short, the size of the power supply structure is relatively small, and the size of the screen driving circuit is reduced, thereby reducing the cost.

Description

Technical Field

[0001] This application relates to the field of screen drivers, and in particular to a power supply structure and a screen driver circuit. Background Technology

[0002] Display screens are widely used in all aspects of life. They work by controlling the flipping of liquid crystal molecules with voltage, which in turn controls the amount of light passing through the liquid crystal molecules. Combined with three-primary-color filtering technology, this allows for the display of images with different colors and brightness levels. The voltage signal controlling the flipping of the liquid crystal molecules comes from the corresponding driving circuit.

[0003] The driving circuit requires a reference voltage generation circuit to drive the screen for display. To make the colors appear more linear to the human eye, gamma calibration is needed for the reference voltage, but the circuit used for gamma calibration is too large. Summary of the Invention

[0004] Therefore, it is necessary to provide a power supply structure and a screen driving circuit that can reduce the size of the power supply structure, thereby reducing the size of the screen driving circuit.

[0005] This application provides a power supply structure for a screen driving circuit, including:

[0006] A positive voltage domain structure, wherein the positive voltage domain structure supports output voltage in the positive voltage domain;

[0007] A negative voltage domain structure that supports outputting a negative voltage domain, wherein the voltages in the positive voltage domain and the negative voltage domain have opposite polarities;

[0008] A low-voltage domain structure that supports outputting a low-voltage domain voltage; the low-voltage domain voltage contains voltages of opposite polarity, the low-voltage domain voltage being less than the positive voltage domain voltage, and the low-voltage domain voltage being less than the negative voltage domain voltage.

[0009] In one embodiment, the low-voltage domain structure supports access to different low-voltage power supplies, which are used to provide voltage thresholds for the low-voltage domain at positive and negative polarities.

[0010] In one embodiment, the different low-voltage power supplies include a digital power supply DVDD and a digital power supply negative voltage supply NVDD; the voltage output by the digital power supply DVDD is the voltage threshold value of the low voltage domain in the positive polarity, and the voltage output by the digital power supply negative voltage supply NVDD is the voltage threshold value of the low voltage domain in the negative polarity.

[0011] In one embodiment, the voltage of the low voltage domain includes a low-voltage gamma voltage; the screen driving circuit is configured to calibrate and convert a reference voltage of the screen driving circuit into a target voltage based on the low-voltage gamma voltage, and drive the screen for display using the target voltage.

[0012] In one embodiment, the reference voltage includes a low-voltage reference voltage in the low-voltage domain and a high-voltage reference voltage in the high-voltage domain. After the screen driving circuit samples the low-voltage gamma voltage and the low-voltage reference voltage, the screen driving circuit converts the sampled voltage with the high-voltage reference voltage to obtain the target voltage.

[0013] In one embodiment, the voltage difference between the low-voltage reference voltage of the low-voltage domain and the voltage of the low-voltage domain is less than or equal to the difference between the low-voltage reference voltage and the voltage threshold of the low-voltage domain in the positive polarity; or, the voltage difference between the low-voltage reference voltage of the low-voltage domain and the voltage of the low-voltage domain is less than or equal to the difference between the low-voltage reference voltage and the voltage threshold of the low-voltage domain in the negative polarity.

[0014] In one embodiment, the voltage of the low voltage domain is used to transmit data.

[0015] In one embodiment, the positive voltage domain structure supports access to analog power supply AVDD and analog ground AVSS; the voltage output by analog power supply AVDD is greater than the voltage of analog ground AVSS.

[0016] In one embodiment, the negative voltage domain structure supports access to analog ground AVSS and analog negative voltage AVEE; the voltage output by the analog ground AVSS is greater than the voltage output by the analog negative voltage AVEE.

[0017] This application also provides a screen driving circuit that uses the power supply structure described in any of the above embodiments.

[0018] In the power supply structure of the aforementioned screen driver circuit, due to the relatively large voltage difference in the high-voltage domain, positive and negative voltage domain structures are used to output voltages in the positive and negative voltage domains respectively, thus providing two voltages within the high-voltage domain and ensuring the normal power supply to high-voltage devices. Simultaneously, because the relatively small voltage difference in the low-voltage domain allows the same low-voltage domain structure to output voltages of opposite polarities, reducing the number of voltage domain structures in the power supply. Furthermore, since different power domains need to be separated by a significant distance, reducing the number of power domains allows for shorter distances between them, resulting in a smaller power supply structure and consequently, a smaller screen driver circuit, reducing costs. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the voltage drive circuit architecture;

[0021] Figure 2 This is a schematic diagram of the original gamma voltage curve;

[0022] Figure 3 This is a schematic diagram of the power supply structure in one embodiment;

[0023] Figure 4 This is a schematic diagram of the low-voltage domain structure in one embodiment;

[0024] Figure 5 This is a schematic diagram of the gamma voltage curve of a specific embodiment;

[0025] Figure 6 A schematic diagram of the gamma voltage curve in the low voltage domain of a specific embodiment;

[0026] Figure 7 This is a schematic diagram of a power supply structure in a traditional technology.

[0027] Figure 8 This is a schematic diagram of the power supply structure in a specific embodiment;

[0028] Figure 9 This is a circuit diagram of the screen driving circuit related to the low-voltage gamma voltage in one embodiment.

[0029] Explanation of reference numerals in the attached figures: 310 - positive voltage domain structure; 320 - low voltage domain junction; 330 - negative voltage domain structure. Detailed Implementation

[0030] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0032] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0033] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0034] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0035] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0036] like Figure 1 As shown, existing display driving circuits include a reference voltage generation circuit, a reference voltage selection circuit, and a buffer. During display, not all generated reference voltages are sent to the buffer; only one level is selected by the selection circuit to control the liquid crystal molecules. Therefore, gamma correction is also performed on this single level. The gamma correction curve shows the X-axis representing different voltage points and the Y-axis representing the ratio of the voltage to the highest voltage, as shown... Figure 2 As shown.

[0037] The power supply structure of a display driver circuit is used to control the voltage within a corresponding voltage range to supply power to the screen driver circuit. The components in the screen driver circuit can be divided into two types: high-voltage components and low-voltage components. Because low-voltage components have a smaller area than high-voltage components, the chip area is reduced. At the same time, high-voltage and low-voltage components can be powered by voltages of opposite polarity to prevent polarization of the liquid crystal molecules in the screen.

[0038] It's important to understand that to prevent polarization of LCD liquid crystal molecules, positive and negative voltage driving circuits are typically used. This means the driving unit is divided into positive and negative voltage sections, usually in equal numbers. Therefore, at any given time, half of the driving voltage is positive, and the other half is negative. The same liquid crystal molecule is driven by positive voltage half the time and negative voltage half the time. This alternating positive and negative voltage drive prevents liquid crystal molecule polarization. Consequently, the gamma curve is divided into positive voltage gamma curves and negative voltage gamma curves, which may lead to excessively large chip sizes.

[0039] Therefore, it can be seen that the power supply structure of the screen driver circuit requires voltages with opposite polarities in the high voltage domain and low voltage domains with opposite polarities for driving. The excessive number of voltage domain structures required leads to an excessively large power supply structure, which in turn may result in an excessively large screen driver circuit.

[0040] In one embodiment, such as Figure 3 As shown, this application provides a power supply structure for a screen driving circuit. The power supply structure includes: a positive voltage domain structure 310, which supports outputting a voltage in the positive voltage domain; a negative voltage domain structure 320, which supports outputting a voltage in the negative voltage domain, wherein the voltages in the positive and negative voltage domains have opposite polarities; and a low voltage domain structure 330, which supports outputting a voltage in the low voltage domain. The voltage in the low voltage domain contains voltages with opposite polarities, and the voltage in the low voltage domain is less than the voltage in the positive voltage domain and less than the voltage in the negative voltage domain.

[0041] Positive voltage domain structure 310 is a power supply structure designed for the positive voltage domain, used to output voltage in the positive voltage domain. Negative voltage domain structure 320 is a power supply structure designed for the negative voltage domain, used to output voltage in the negative voltage domain. Low voltage domain structure 330 is a power supply structure designed for the low voltage domain, used to output voltage in the low voltage domain.

[0042] Positive voltage domain structure 310, negative voltage domain structure 320 and low voltage domain structure 330 are all voltage domain structures used to connect a pair of voltages. Since the pair of voltages connected to these three voltage domain structures are of different types, they can output voltages of different voltage domains.

[0043] Optionally, the positive voltage domain structure 310, the negative voltage domain structure 320, and the low voltage domain structure 330 can use the same or different structures to connect to an external power supply. The structure used to connect to an external power supply includes, but is not limited to, at least one pair of pins and / or at least one pair of metal wires.

[0044] The voltage in the positive voltage domain is positive relative to the high-voltage reference voltage, and the voltage in the negative voltage domain is negative relative to the high-voltage reference voltage. Therefore, the voltages in the positive and negative voltage domains have opposite polarities; that is, the positive voltage domain is higher than the high-voltage reference voltage, and the negative voltage domain is lower than the high-voltage reference voltage. Thus, the voltage difference between the two domains creates voltages of opposite polarities. Because the voltage difference between opposite polarities is relatively large in the high-voltage domain, separate voltage domain structures are used for power supply.

[0045] Optionally, the high-voltage reference voltage in both the positive and negative voltage domains can be the same value. Relative to the voltage in the low voltage domain, the voltages in both the positive and negative voltage domains are voltages in the high voltage domain, used to power high-voltage devices.

[0046] The low voltage domain includes positive and negative voltages. The positive voltage in the low voltage domain is positive relative to the low voltage reference voltage, and the negative voltage in the low voltage domain is negative relative to the low voltage reference voltage. That is, the positive voltage in the low voltage domain is greater than the low voltage reference voltage, and the negative voltage in the low voltage domain is less than the low voltage reference voltage.

[0047] The positive voltage domain, negative voltage domain, and low voltage domain are all voltage ranges. Since the positive voltage domain structure 310, negative voltage domain structure 320, and low voltage domain structure 330 are connected to different types of voltages, the positive voltage domain and negative voltage domain are different from the low voltage domain in terms of polarity and magnitude.

[0048] In terms of polarity, the voltages in the positive and negative voltage domains are polarized based on a high-voltage reference voltage, and are output by different voltage domain structures to ensure the high-voltage domain has voltages of opposite polarity. Conversely, the voltages in the low-voltage domain are polarized based on a low-voltage reference voltage, and are output by a low-voltage domain structure (structure 330) to ensure the low-voltage domain has voltages of opposite polarity. Numerically, the voltages in both the positive and negative voltage domains are greater than the voltage in the low-voltage domain, while the voltages in the positive and negative voltage domains may be equal or different.

[0049] Both the high-voltage and low-voltage reference voltages are reference voltages that can be used to drive the screen for display. Because they belong to different voltage domains, the high-voltage reference voltage is higher than the low-voltage reference voltage. Optionally, from a usage perspective, the low-voltage reference voltage is used for sampling, while the high-voltage reference voltage is used to generate the target voltage. Optionally, the low-voltage domain of the screen driving circuit includes voltages lower than a certain low-voltage domain threshold.

[0050] In the power supply structure of the aforementioned screen driver circuit, due to the relatively large voltage difference in the high-voltage domain, the positive voltage domain structure 310 and the negative voltage domain structure 320 output voltages from the positive and negative voltage domains respectively, thus providing two voltages within the high-voltage domain and ensuring the normal power supply to the high-voltage devices. Simultaneously, because the voltage difference in the low-voltage domain is relatively small, the same low-voltage domain structure 330 can output voltages of opposite polarities, thereby reducing the number of voltage domain structures in the power supply. Since different power domains need to be separated by a large distance, reducing the number of power domains allows for shorter distances between them, resulting in a smaller power supply structure and consequently a smaller screen driver circuit. Consequently, circuits such as voltage buffers, digital circuits for transmitting and storing data, analog-to-digital converters, and level conversion circuits can all be reduced in size and cost.

[0051] In one embodiment, the low-voltage domain structure 330 supports access to different low-voltage power supplies, which are used to provide voltage thresholds for the low-voltage domain at positive and negative polarities.

[0052] A low-voltage power supply is a power source whose output voltage is less than or equal to a certain low-voltage threshold. Different low-voltage values ​​can output different voltages to create a voltage difference within the low-voltage domain, which then powers low-voltage devices. In some applications, the low-voltage threshold can be, but is not limited to, 1.2V, 1.8V, 2.5V, 5V, etc., while the voltage output by the screen driver circuit is greater than the high-voltage threshold; optionally, the high-voltage threshold can be 5V, 12V, etc.

[0053] Optionally, one low-voltage domain output voltage is greater than the low-voltage reference voltage to form a voltage threshold value for the low-voltage domain in the positive polarity; the other low-voltage domain output voltage is less than the low-voltage reference voltage to form a voltage threshold value for the low-voltage domain in the negative polarity.

[0054] In this embodiment, the low voltage domain structure 330 is directly connected to different low voltage power supplies, and these two low voltage power supplies can provide voltages with opposite polarities, so that the low voltage domain structure 330 can guarantee the corresponding voltage threshold through different low voltage power supplies.

[0055] In one embodiment, such as Figure 4 As shown, different low-voltage power supplies include digital power supply DVDD and digital power supply negative voltage power supply NVDD; the voltage output by digital power supply DVDD is the voltage threshold value of the low voltage domain in the positive polarity, and the voltage output by digital power supply negative voltage power supply NVDD is the voltage threshold value of the low voltage domain in the negative polarity.

[0056] DVDD stands for Digital Voltage Drain. NVDD stands for Negative Digital Voltage Drain.

[0057] Optionally, the digital power supply DVDD outputs a voltage of +1.2V, and the digital power supply negative voltage NVDD outputs a voltage of -1.2V, thus creating a voltage difference of 2.4V in the low voltage range. Optionally, the digital power supply DVDD outputs a voltage of +1.8V, and the digital power supply negative voltage NVDD outputs a voltage of -1.8V, thus creating a voltage difference of 3.6V in the low voltage range.

[0058] In this embodiment, since the devices on the analog circuit require a larger signal amplitude to process, while the devices on the digital circuit can more sensitively identify the characteristics of signal changes, the low-voltage domain structure 330 of the screen driving circuit is connected to DVDD and NVDD, so that this low-voltage domain structure is within the digital circuit, thereby ensuring the normal operation of the screen driving circuit while reducing the circuit area.

[0059] In one embodiment, the voltage in the low voltage domain includes a low-voltage gamma voltage; the screen driving circuit is configured to calibrate and convert the reference voltage of the screen driving circuit to a target voltage based on the low-voltage gamma voltage, and drive the screen for display using the target voltage.

[0060] Low-voltage gamma voltage is a calibration voltage in the low-voltage domain, and it can be a voltage with either positive or negative polarity. Low-voltage gamma voltage is... Figure 2 The original gamma curve was split into multiple segments, and the voltage value of each segment was reduced to the low-voltage domain of its respective screen driver circuit. The gamma voltage variation pattern within each segment matches the variation pattern of the original gamma, and the gamma voltage within each segment is within the low-voltage domain. When the gamma voltage within each segment is at its minimum value, the ratio of the gamma voltage within each segment to the maximum voltage is 0; when the gamma voltage within each segment is at its maximum value, the ratio of the gamma voltage within each segment to the maximum voltage is the maximum value set within the low-voltage domain.

[0061] Optionally, such as Figure 5As shown in (a), the curve of the original gamma voltage is divided into four segments, and the change pattern of the gamma voltage in each segment matches the change pattern of the original gamma voltage; the magnitude, relative relationship, and change pattern of the gamma voltage in each segment are as follows: Figure 5 As shown in (b).

[0062] The target voltage is the voltage output from the screen driving circuit to the screen, which can be used to drive the movement of liquid crystal molecules on the screen to form a rich picture.

[0063] In an optional embodiment, the reference voltage of the screen driving circuit is calibrated and converted into the target voltage based on the low-voltage gamma voltage. This means: first, the low-voltage gamma voltage is amplified into a high-voltage gamma voltage in the high-voltage domain; then, the high-voltage gamma voltage and the high-voltage reference voltage are input to different input terminals of the operational amplifier, and the target voltage is output through the operational amplifier.

[0064] In this embodiment, since the voltage in the low-voltage domain includes low-voltage gamma voltage, the reference voltage selection circuit can also be generated using low-voltage devices. Because low-voltage devices have a smaller area than high-voltage devices, the chip area is reduced.

[0065] In another optional embodiment, the reference voltage includes a low-voltage reference voltage in the low-voltage domain and a high-voltage reference voltage in the high-voltage domain. After the screen driving circuit samples the low-voltage gamma voltage and the low-voltage reference voltage, the screen driving circuit converts the sampled voltage with the high-voltage reference voltage to obtain the target voltage.

[0066] In one feasible embodiment, the screen driving circuit includes: a sampling circuit configured to sample based on a low-voltage gamma voltage and a low-voltage reference voltage; an operational amplifier connected to a high-voltage reference voltage and configured to output a target voltage based on the high-voltage reference voltage and the voltage sampled by the sampling circuit, so as to drive the screen with the target voltage.

[0067] In this embodiment, since the screen driving circuit is connected to a high-voltage reference voltage, the reference voltage received by the screen driving circuit can be stabilized, which can avoid the voltage domain switching of the reference voltage affecting the time for the screen driving circuit to generate the target voltage. Therefore, the screen driving circuit can quickly establish and output the target voltage to support high refresh rate screens.

[0068] In one embodiment, the voltage difference between the low-voltage reference voltage of the low-voltage domain and the voltage of the low-voltage domain is less than or equal to the difference between the low-voltage reference voltage and the voltage threshold of the low-voltage domain in the positive polarity; or, the voltage difference between the low-voltage reference voltage of the low-voltage domain and the voltage of the low-voltage domain is less than or equal to the difference between the low-voltage reference voltage and the voltage threshold of the low-voltage domain in the negative polarity.

[0069] The low-voltage reference voltage is the reference voltage within the low-voltage domain.

[0070] Since the low voltage domain structure 330 has two polarities at the same time, and the voltage of the low voltage domain is a shift voltage output by the low voltage domain structure 330 for different situations, the shift voltage is a positive voltage of the low voltage domain for a period of time and a negative voltage of the low voltage domain for another period of time. Therefore, when the low voltage domain combines the positive and negative voltage domains, the voltage magnitude of the low voltage domain has two possibilities.

[0071] One scenario is that the voltage difference between the low-voltage reference voltage and the voltage in the low-voltage domain is less than or equal to the difference between the low-voltage reference voltage and the voltage threshold value of the low-voltage domain in the positive polarity; another scenario is that the voltage difference between the low-voltage reference voltage in the low-voltage domain and the voltage in the low-voltage domain is less than or equal to the difference between the low-voltage reference voltage and the voltage threshold value of the low-voltage domain in the negative polarity.

[0072] In one specific embodiment, the low-voltage domain structure 330 supports access to both a digital power supply DVDD and a digital power supply negative voltage source NVDD; the voltage output by the digital power supply DVDD is the voltage threshold value of the low-voltage domain in the positive polarity, and the voltage output by the digital power supply negative voltage source NVDD is the voltage threshold value of the low-voltage domain in the negative polarity. In this case, the low-voltage gamma curves for these two scenarios are as follows: Figure 6 As shown.

[0073] In this embodiment, when both the positive and negative voltage domains of the low voltage domain are output by the same low voltage domain structure 330, the low voltage domain structure 330 can output voltages of opposite polarities. Therefore, the voltage domain corresponding to the low voltage domain structure 330 simultaneously has both positive and negative voltage domains.

[0074] In one embodiment, the voltage in the low voltage domain is used to transmit data.

[0075] Optionally, the voltage in the low voltage domain varies between a positive voltage threshold and a negative voltage threshold to encode and transmit data.

[0076] In this embodiment, the low-voltage domain structure 330 outputs a low-voltage domain voltage to transmit data, thereby acting as a low-voltage gamma voltage or other voltage to reduce the circuitry in the high-voltage domain, thus reducing the overall circuit size.

[0077] In one embodiment, the positive voltage domain structure 310 supports access to both analog power supply AVDD and analog ground AVSS; the voltage output by analog power supply AVDD is greater than the voltage of analog ground AVSS.

[0078] Analog power supply AVDD stands for Analog Voltage Drain. It provides power to the analog circuitry of the screen control circuitry. The voltage output by AVDD is higher than that output by the digital power supply DVDD, providing higher precision analog signal processing. Analog ground AVSS stands for Analog Voltage Source. AVSS provides a high-voltage ground voltage, which can be a high-voltage reference voltage. Because the voltage output by AVDD is greater than that of AVSS, a positive voltage domain structure 310 is formed in the analog circuitry to output a positive voltage domain voltage.

[0079] In one embodiment, the negative voltage domain structure 320 supports access to analog ground AVSS and analog negative voltage AVEE; the voltage output by analog ground AVSS is greater than the voltage output by analog negative voltage AVEE.

[0080] Analog Voltage Emitter (AVEE) is a voltage output voltage lower than the ground potential provided by analog ground (AVSS) in an analog circuit. This creates a negative voltage domain structure 320 in the analog circuit, outputting a voltage in the negative voltage domain.

[0081] Traditional technologies such as Figure 7 It includes four voltage domains: positive and negative output voltage domains using high-voltage devices, and positive and negative output voltage domains using low-voltage devices. Specifically, the positive output voltage domain using high-voltage devices is used to connect the analog power supply AVDD and analog ground AVSS; the negative output voltage domain using high-voltage devices is used to connect the analog negative voltage AVEE1 and analog ground AVSS; the positive output voltage domain using low-voltage devices is used to connect the digital power supply (DVDD) and digital ground (DVSS); and the negative output voltage domain using low-voltage devices is used to connect the digital ground (DVSS) and digital power supply negative voltage (NVDD).

[0082] Correspondingly, this implementation example Figure 8As shown, the system includes three voltage domains: a positive voltage domain structure 310 supports the connection of analog power supply AVDD and analog ground AVSS, forming a positive voltage domain within the high-voltage domain; a negative voltage domain structure 320 supports the connection of analog ground AVSS and analog negative voltage AVEE, forming a negative voltage domain within the high-voltage domain; and a low-voltage domain structure 330 supports the connection of digital power supply DVDD and digital power supply negative voltage NVDD, forming a positive and negative voltage domain within the low-voltage domain. Therefore, compared to traditional technologies, this embodiment takes into account the relatively small voltage difference in the low-voltage domain, allowing the same low-voltage domain structure 330 to output voltages of opposite polarities, thus reducing the number of voltage domain structures in the power supply. Since different power domains need to be separated by a large distance, reducing the number of power domains allows for shorter distances between power domains, resulting in a smaller power supply structure size and consequently a smaller screen driving circuit size.

[0083] In one embodiment, this application provides a screen driving circuit including the power supply structure in any of the above embodiments.

[0084] Optionally, the power supply structure may include, but is not limited to, at least one pair of pins, at least one pair of data lines, or at least one pair of other input terminals of the screen driver circuit.

[0085] In a specific embodiment, such as Figure 9 As shown, the screen driving circuit includes a first buffer buf1, a second buffer buf1, a sampling circuit, and an operational amplifier. The sampling circuit includes a sampling capacitor C, switches S1 and S2. The power supply structure is as follows: the input terminal of the low-voltage gamma voltage is connected to the input terminal of the first buffer buf1, and the output terminal of the first buffer buf1 is connected to the first terminal of the sampling capacitor C via switch S1; the input terminal of the low-voltage reference voltage is connected to the input terminal of the second buffer buf2, and the output terminal of the second buffer buf2 is connected to the second terminal of the sampling capacitor C via switch S2; the non-inverting input terminal of the operational amplifier is connected to the high-voltage reference voltage, the second terminal of the sampling capacitor C is connected to the inverting input terminal of the operational amplifier via switch S3, and the output terminal of the operational amplifier is connected to the first terminal of the sampling capacitor via switch S4; the output terminal of the operational amplifier is also connected to the inverting input terminal of the operational amplifier via switch S5. Switch S2 connects the second terminal of the sampling capacitor C to the input terminal of the second buffer buf2; the inverting input terminal of the operational amplifier is connected to the second terminal of the sampling capacitor C via switch S3; and the output terminal of the operational amplifier is connected to the first terminal of the sampling capacitor via switch S4.

[0086] During the sampling phase, switches S1 and S2 are closed to allow the sampling capacitor C to sample. Simultaneously, switch S5 is closed for negative feedback, aligning the voltages at the non-inverting and inverting inputs of the operational amplifier, while switches S3 and S4 are opened. During the output phase, switches S1, S2, and S5 provide negative feedback, and switches S3 and S4 are closed to release the charge collected by capacitor C, forming the target voltage, which drives the liquid crystal molecules on the screen.

[0087] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0088] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0089] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A power supply structure for a screen driving circuit, characterized in that, include: A positive voltage domain structure, wherein the positive voltage domain structure supports output voltage in the positive voltage domain; A negative voltage domain structure that supports outputting a negative voltage domain, wherein the voltages of the positive voltage domain and the negative voltage domain have opposite polarities; A low-voltage domain structure that supports outputting a low-voltage domain voltage; the low-voltage domain voltage contains voltages of opposite polarity, the low-voltage domain voltage is less than the positive voltage domain voltage, and the low-voltage domain voltage is less than the negative voltage domain voltage.

2. The power supply structure according to claim 1, characterized in that, The low-voltage domain structure supports access to different low-voltage power supplies, which are used to provide the voltage threshold values ​​of the low-voltage domain in terms of positive and negative polarities.

3. The power supply structure according to claim 2, characterized in that, The different low-voltage power supplies include a digital power supply DVDD and a digital power supply negative voltage power supply NVDD; the voltage output by the digital power supply DVDD is the voltage threshold value of the low voltage domain in the positive polarity, and the voltage output by the digital power supply negative voltage power supply NVDD is the voltage threshold value of the low voltage domain in the negative polarity.

4. The power supply structure according to claim 1, characterized in that, The voltage in the low voltage domain includes a low-voltage gamma voltage; the screen driving circuit is configured to calibrate and convert the reference voltage of the screen driving circuit into a target voltage based on the low-voltage gamma voltage, and drive the screen to display using the target voltage.

5. The power supply structure according to claim 4, characterized in that, The reference voltage includes a low-voltage reference voltage in the low-voltage domain and a high-voltage reference voltage in the high-voltage domain. After the screen driving circuit samples the low-voltage gamma voltage and the low-voltage reference voltage, the screen driving circuit converts the sampled voltage with the high-voltage reference voltage to obtain the target voltage.

6. The power supply structure according to claim 1, characterized in that, The voltage difference between the low-voltage reference voltage in the low-voltage domain and the voltage in the low-voltage domain is less than or equal to the difference between the low-voltage reference voltage and the voltage threshold value of the low-voltage domain in the positive polarity. Alternatively, the voltage difference between the low-voltage reference voltage of the low-voltage domain and the voltage of the low-voltage domain is less than or equal to the difference between the low-voltage reference voltage and the voltage threshold of the low-voltage domain in negative polarity.

7. The power supply structure according to claim 1, characterized in that, The voltage in the low voltage domain is used for data transmission.

8. The power supply structure according to claim 1, characterized in that, The positive voltage domain structure supports the connection of analog power supply AVDD and analog ground AVSS; the voltage output by analog power supply AVDD is greater than the voltage of analog ground AVSS.

9. The power supply structure according to claim 1, characterized in that, include: The negative voltage domain structure supports access to analog ground AVSS and analog negative voltage AVEE; The voltage output by the simulated ground AVSS is greater than the voltage output by the simulated negative voltage AVEE.

10. A screen driving circuit, characterized in that, Includes the power supply structure according to any one of claims 1-9.

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