Driving chip power supply circuit and display device

Abstract

The application discloses a driving chip power supply circuit and a display device. The driving chip power supply circuit comprises a voltage comparison module connected to a power supply chip, which is used to generate a first voltage level according to a first power supply and a second power supply; a first power supply module connected to the voltage comparison module and receiving the first voltage level; and a second power supply module connected to the voltage comparison module and receiving the first voltage level. The output ends of the first power supply module and the second power supply module are connected to a driving chip. The first voltage level comprises a high voltage level and a low voltage level. The first power supply module and the second power supply module are selectively turned on according to the first voltage level to provide corresponding power supply voltages to the driving chip. The application improves the power supply of the driving chip of the display device and avoids the problem that the voltage backflow causes the abnormal working of the chip.

Description

Technical Field

[0001] This utility model relates to the field of display technology, and more specifically, to a power supply circuit for a driver chip and a display device. Background Technology

[0002] With the rapid development of display technology, driver chips (such as source driver chips and gate driver chips) are playing an increasingly crucial role in display devices. These chips require a stable and compliant power supply voltage to ensure the normal operation of the display panel.

[0003] Many existing chip power supply designs use fixed power management schemes, which are difficult to meet the above requirements. Specifically, for example... Figure 1 As shown, the outputs of the existing power supply chip are directly supplied to the driver chip. The measured waveforms of this method are as follows. Figure 2 As shown, its AVDD and HAVDD will exhibit abnormal stepped waveforms as indicated by the red box, and the steps rise after XVCC, which does not meet the design requirements of the source driver chip. This may lead to driver chip malfunction, resulting in abnormal display and inability to display normally.

[0004] Therefore, there is an urgent need for a power supply circuit for driver chips to provide stable and reliable power supply to driver chips and avoid problems such as voltage backflow. Utility Model Content

[0005] The purpose of this invention is to provide a power supply and display device for a driver chip, which aims to improve the power supply of the driver chip in the display device, avoid the problem of voltage backflow causing abnormal chip operation, and thus improve the stability and reliability of the device.

[0006] According to one aspect of the present invention, a power supply circuit for a driver chip is provided, comprising: a voltage comparison module connected to a power supply chip, used to generate a first level according to a first power supply and a second power supply; a first power supply module connected to the voltage comparison module, receiving the first level; and a second power supply module connected to the voltage comparison module, receiving the first level; wherein the first power supply module and the second power supply module are selectively turned on according to the first level to provide a corresponding power supply voltage to the driver chip.

[0007] In the aforementioned power supply circuit for the driver chip, the voltage comparison module includes a voltage comparator. The first power supply is connected to the inverting input terminal of the voltage comparator, and the second power supply is connected to the non-inverting input terminal of the voltage comparator. The output terminal of the voltage comparator provides a first level to the first power supply module and the second power supply module, respectively.

[0008] The power supply circuit for the aforementioned driver chip further includes a first resistor and a second resistor in the voltage comparison module. One end of the first resistor receives a first power supply, and the other end of the first resistor is connected to the inverting input terminal of the voltage comparator. One end of the second resistor receives a second power supply, and the other end of the second resistor is connected to the non-inverting input terminal of the voltage comparator.

[0009] The aforementioned driver chip power supply circuit, wherein the first power supply module includes: a third resistor, one end of which is connected to the output terminal of the voltage comparator; and a first switching transistor, wherein the control terminal of the first switching transistor receives the first level from the output terminal of the voltage comparator via the third resistor, the first path terminal of the first switching transistor receives the first power supply, and the second path terminal of the switching transistor is connected to the driver chip; and a fourth resistor, wherein the fourth resistor is disposed between the first path terminal of the first switching transistor and the first power supply.

[0010] Optionally, the second power supply module includes: a fifth resistor, one end of which is connected to the output of the voltage comparator; a second switch, the control terminal of which receives the first level from the output of the voltage comparator via the fifth resistor, the first path terminal of which receives the first power supply, and the second path terminal of which is grounded; a sixth resistor and a seventh resistor, which are sequentially disposed between the first path terminal of the second switch and the first power supply; wherein the output of the second power supply module is led out from the node between the sixth resistor and the seventh resistor.

[0011] Optionally, the first switch is a P-channel MOS field-effect transistor, with the control terminal of the first switch being the gate, the first pass terminal of the first switch being the source, and the second pass terminal of the first switch being the drain; the second switch is an N-channel MOS field-effect transistor, with the control terminal of the second switch being the gate, the first pass terminal of the second switch being the drain, and the second pass terminal of the second switch being the source.

[0012] Optionally, the second power supply module further includes a capacitor, one end of which is connected to the node between the sixth resistor and the seventh resistor, and the other end of which is grounded.

[0013] According to another aspect of the present invention, a display device is provided, comprising: a power chip for providing a first power supply and a second power supply; a driving chip power supply circuit described above, receiving the first power supply and the second power supply and outputting a power supply voltage; and a display panel for displaying images based on image data; wherein at least a portion of the driving chips of the display panel are powered by the power supply voltage.

[0014] Optionally, the display panel includes: a gate driver chip for providing gate drive data; a source driver chip for providing source drive data; and an array substrate for displaying images based on the source drive data and the gate drive data, wherein the power supply for the source driver chip is provided by the supply voltage.

[0015] The driver chip power supply circuit and display device provided in this embodiment of the utility model avoid the problem of abnormal operation of the driver chip caused by voltage backflow by setting up the driver chip power supply circuit. Furthermore, the driver chip power supply circuit has a simple structure, occupies a small area, and is easy to implement, which can effectively improve the stability and reliability of the product. Attached Figure Description

[0016] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the present invention with reference to the accompanying drawings.

[0017] Figure 1 A schematic diagram illustrating chip power supply in the prior art;

[0018] Figure 2 The waveform diagram of chip power supply in the prior art is shown;

[0019] Figure 3 A schematic diagram of the power supply circuit for the driver chip according to an embodiment of the present invention is shown.

[0020] Figure 4 A schematic diagram of the power supply circuit for the driver chip according to an embodiment of the present invention is shown;

[0021] Figure 5 A schematic diagram of a display device according to an embodiment of the present invention is shown. Detailed Implementation

[0022] The present invention will now be described in more detail with reference to the accompanying drawings. To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of the present application are shown in the drawings. However, the present application may be implemented in different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0023] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0024] In the description of this application, the words "exemplary" or "for example" are used to indicate that they are examples, illustrations, or descriptions. Any embodiment described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments. "And / or" in this document describes an association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. "Connection" describes a connection relationship between related objects. For example, A and B are connected, which can indicate a direct connection between A and B, or an indirect connection between A and B through other devices / units / modules. "Multiple" refers to two or more. Furthermore, to facilitate a clear description of the technical solutions of the embodiments of this application, the terms "first," "second," etc., are used to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first," "second," etc., do not limit the quantity or execution order, and that "first," "second," etc., do not necessarily imply differences.

[0025] Furthermore, the same reference numerals in the figures denote the same or similar structures, thus repeated descriptions of them will be omitted. That is, the various parts in this specification are described using a combination of parallel and progressive methods, with each part focusing on its differences from the others. Similar or identical parts can be referred to interchangeably. Terms expressing position and direction described in this application are illustrative based on the accompanying drawings, but changes can be made as needed, and all such changes are included within the scope of protection of this application. The accompanying drawings in this application are for illustrating relative positional relationships only and do not represent actual scale.

[0026] This application describes many specific details of the present invention, such as the specific structure, dimensions, connection relationships, and techniques of the modules, in order to provide a clearer understanding of the present invention. However, as those skilled in the art will understand, the present invention may be implemented without following these specific details.

[0027] This utility model can be presented in various forms, some of which will be described below.

[0028] Figure 3 This diagram illustrates a module schematic of the power supply circuit for a driver chip according to an embodiment of the present invention. The power supply chip 100 supplies power to the driver chip 500 through the power supply circuit, which includes a voltage comparison module 200, a first power supply module 300, and a second power supply module 400. Specifically, the power supply chip 100 provides a first power supply VCC and a second power supply Vref, where the second power supply Vref is, for example, a reference power supply. The power supply chip 100 provides the first power supply VCC and the second power supply Vref to the voltage comparison module 200. The voltage comparison module 200 outputs a first level based on the comparison result of the first power supply VCC and the second power supply Vref, and provides the first level to the first power supply module 300 and the second power supply module 400 respectively. The first power supply module 300 and the second power supply module 400 selectively conduct based on the high or low level of the first level, and the conducting power supply module supplies power to the driver chip 500; that is, the first power supply module 300 and the second power supply module 400 selectively conduct based on the high or low level of the first level, selectively using either the first power supply module 300 or the second power supply module 400 to provide the power supply voltage to the driver chip 500.

[0029] The first power supply VCC and the second power supply Vref first enter the voltage comparison module 200. After passing through the voltage comparison module 200, the first level is output. The first power supply module 300 and the second power supply module 400 select one to conduct according to the high or low level of the first level and provide power supply voltage to the driver chip 500.

[0030] The voltage comparison module 200 is implemented, for example, using a differential comparator structure. Its non-inverting input is connected to the second power supply Vref, its inverting input is connected to the first power supply VCC, and its output generates a first-level signal with hysteresis characteristics. This comparator has a built-in positive feedback network, which can effectively prevent output jitter when the voltage of the first power supply VCC fluctuates.

[0031] Specifically, if the first level is high, the first switch M1 in the first power supply module 300 is turned off, and the second switch M2 in the second power supply module 400 is turned on, so that the second power supply module 400 provides an appropriate power supply voltage to the driver chip 500 to power the driver chip; if the first level is low, the first switch M1 in the first power supply module 300 is turned on, and the second switch M2 in the second power supply module 400 is turned off, so that the first power supply module 300 provides an appropriate power supply voltage to the driver chip 500 to power the driver chip.

[0032] Figure 4 This diagram shows a schematic of the power supply circuit for the driver chip according to an embodiment of the present invention; from Figure 4As can be seen from the diagram, the voltage comparison module 200 includes, for example, resistors R1 and R2 and a voltage comparator. One end of resistor R1 is connected to the power chip 100 to receive the first power supply VCC, and the other end of resistor R1 is connected to the inverting input of the voltage comparator. One end of resistor R2 is connected to the power chip 100 to receive the second power supply Vref, and the other end of resistor R2 is connected to the non-inverting input of the voltage comparator. The output of the voltage comparator provides a first level to the first power supply module 300 and the second power supply module 400 respectively. The first power supply module 300 and the second power supply module 400 selectively conduct to supply power to the driver chip 500 according to the high or low level of the first level.

[0033] Specifically, when the voltage of the first power supply VCC is greater than or equal to the voltage of the second power supply Vref, the first level output by the voltage comparator is low; when the voltage of the first power supply VCC is less than the voltage of the second power supply Vref, the first level output by the voltage comparator is high.

[0034] The first power supply module 300 includes, for example, resistors R3 and R4, and a switching transistor M1. The first end of resistor R3 is connected to the output of a voltage comparator to receive a first voltage level, and the other end of resistor R3 is connected to the control terminal of the switching transistor M1, whereby the first voltage level controls the switching on and off of the transistor M1. The switching transistor M1 is, for example, a P-channel MOS field-effect transistor, with its control terminal being the gate, its first pass terminal being the source, and its second pass terminal being the drain. The first pass terminal of the switching transistor M1 is connected to the first power supply VCC through resistor R4, and the second pass terminal of the switching transistor M1 is directly connected to the driver chip 500. When the switching transistor M1 is turned on, the first power supply VCC directly supplies power to the driver chip 500 through resistor R4 and the switching transistor M1.

[0035] The second power supply module 400 includes, for example, resistors R5, R6, and R7, capacitor C1, and a switching transistor M2. One end of resistor R5 is connected to the output of a voltage comparator to receive a first voltage level, and the other end of resistor R5 is connected to the control terminal Vg of the switching transistor M2, which is controlled by the first voltage level to turn the switching transistor M2 on and off. The switching transistor M2 is, for example, an N-channel MOS field-effect transistor, with its control terminal Vg as the gate, its first path terminal Vd as the drain, and its second path terminal Vs as the source. The first path terminal Vd of the switching transistor M2 is connected to the first power supply VCC through resistors R6 and R7 in sequence, and the second path terminal Vs of the switching transistor M2 is grounded. The output voltage VOUT of the second power supply module 400 is led out from the node between resistors R6 and R7. One end of capacitor C1 is connected to the node between resistors R6 and R7, and the other end is grounded to perform filtering and voltage regulation.

[0036] Specifically, when the first level is high, the switch M1 in the first power supply module 300 is turned off. The first level is output to the control terminal Vg of the switch M2 after passing through resistor R5. After receiving the high level first level, the control terminal Vg of the switch M2 turns on. The first power supply VCC controls the voltage value of the output voltage VOUT through the voltage divider of resistors R6 and R7, so that the output voltage VOUT meets the requirements of the driver chip 500. The output voltage VOUT is used as the power supply voltage to power the driver chip 500.

[0037] The core innovation of this driver chip's power supply circuit lies in the dynamic power path switching mechanism implemented through the voltage comparator module 200. When the voltage value of the first power supply VCC is higher than that of the reference power supply Vref, the comparator outputs a low level, triggering the switching transistor M1 of the first power supply module 300 to conduct. At this time, the power supply path exhibits low impedance characteristics, and the first power supply VCC directly supplies power to the driver chip 500 through the first power supply module 300. When the system detects that the VCC voltage drops below the second power supply Vref due to load transients or power fluctuations, the comparator output immediately flips to a high level. At this time, the switching transistor M2 of the second power supply module 400 conducts, and this module outputs the first power supply VCC after a built-in voltage divider design. This dual-mode power supply architecture has significant advantages over traditional linear voltage regulation schemes: First, it maintains a direct power supply path (powered by the first power supply module) when the input voltage is in the normal range (VCC>Vref), resulting in high conversion efficiency; second, it seamlessly switches to a voltage divider power supply mode (powered by the second power supply module) when the input voltage changes, providing the driver chip 500 with an appropriate driving voltage through the internal design of the second power supply module 400.

[0038] Figure 5 The schematic diagram shows a display device according to an embodiment of the present invention. The display device includes a power supply chip, a driver chip power supply circuit, and a display panel. The display panel includes a source driver chip, a gate driver chip, and an array substrate.

[0039] In this embodiment, when the display device is powered on, the power supply chip provides a first power supply VCC and a second power supply Vref to the driver chip power supply circuit. The driver chip power supply circuit then supplies the power supply voltage to the display panel to drive the source driver chip of the display panel. This design effectively avoids the problem of voltage backflow causing abnormal operation of the driver chip due to the second power supply Vref voltage preceding the first power supply VCC, thus improving the stability and reliability of the product.

[0040] This embodiment uses a liquid crystal display device as an example to illustrate the internal structure of the display device. However, the display device of this invention is not limited to a liquid crystal display device; it can also be a plasma display device, an LED display device, an OLED display device, or other types of display devices, and its internal structure is not limited to these. By setting up a power supply circuit for the driver chip, the problem of voltage backflow causing abnormal operation of the driver chip is avoided. Specifically, it effectively solves the problem in the display device where the voltage of the second power supply Vref increases before the voltage of the first power supply VCC, causing voltage backflow and abnormal operation of the driver chip. This avoids display failures caused by abnormal operation of the driver chip and improves the stability and reliability of the product.

[0041] The driver chip power supply circuit and display device provided in this embodiment of the utility model avoid the problem of abnormal operation of the driver chip caused by voltage backflow by setting up the driver chip power supply circuit. Furthermore, the driver chip power supply circuit has a simple structure, occupies a small area, and is easy to implement, which can effectively improve the stability and reliability of the product.

[0042] The embodiments of this utility model described above are examples of specific examples. These embodiments do not exhaustively describe all details, nor do they limit the utility model to only specific embodiments. Obviously, many modifications and variations can be made based on the above description. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to make good use of this utility model and its modifications.

Claims

1. A power supply circuit for a driver chip, characterized in that, include: A voltage comparison module is connected to a power supply chip to receive a first power supply and a second power supply and output a first level. The first power supply module is connected to the voltage comparison module and receives the first voltage level. The second power supply module is connected to the voltage comparison module and receives the first voltage level. The output terminals of both the first power supply module and the second power supply module are connected to the driver chip. The first level includes a high level and a low level. The first power supply module and the second power supply module are selectively turned on according to the first level.

2. The power supply circuit for the driver chip according to claim 1, characterized in that, The voltage comparison module includes a voltage comparator. The first power supply is connected to the inverting input terminal of the voltage comparator, and the second power supply is connected to the non-inverting input terminal of the voltage comparator. The output terminal of the voltage comparator provides a first level to the first power supply module and the second power supply module, respectively.

3. The power supply circuit for the driver chip according to claim 2, characterized in that, The voltage comparison module further includes a first resistor and a second resistor. One end of the first resistor receives a first power supply, and the other end of the first resistor is connected to the inverting input terminal of the voltage comparator. One end of the second resistor receives a second power supply, and the other end of the second resistor is connected to the non-inverting input terminal of the voltage comparator.

4. The power supply circuit for the driver chip according to claim 3, characterized in that, The first power supply module includes: A third resistor, one end of which is connected to the output of the voltage comparator; and The first switching transistor has a control terminal that receives the first level from the output terminal of the voltage comparator via the third resistor, a first path terminal that receives the first power supply, and a second path terminal that is connected to the driver chip. A fourth resistor is disposed between the first path terminal of the first switching transistor and the first power supply.

5. The power supply circuit for the driver chip according to claim 4, characterized in that, The second power supply module includes: A fifth resistor, one end of which is connected to the output of the voltage comparator; and The second switch has its control terminal receiving the first level from the output terminal of the voltage comparator via the fifth resistor, its first path terminal receiving the first power supply, and its second path terminal grounded. The sixth resistor and the seventh resistor are sequentially disposed between the first path terminal of the second switch and the first power supply; The output terminal of the second power supply module is led out from the node between the sixth resistor and the seventh resistor.

6. The power supply circuit for the driver chip according to claim 5, characterized in that, The first switch is a P-channel MOS field-effect transistor, the control terminal of the first switch is the gate, the first pass terminal of the first switch is the source, and the second pass terminal of the first switch is the drain. The second switch is an N-channel MOS field-effect transistor. The control terminal of the second switch is the gate, the first pass terminal of the second switch is the drain, and the second pass terminal of the second switch is the source.

7. The power supply circuit for the driver chip according to claim 6, characterized in that, The second power supply module also includes a capacitor, one end of which is connected to the node between the sixth resistor and the seventh resistor, and the other end of which is grounded.

8. A display device, characterized in that, include: Power chip, used to provide a first power supply and a second power supply; The driver chip power supply circuit as described in any one of claims 1-7 receives the first power supply and the second power supply and outputs a power supply voltage; The display panel shows the image data. The power supply voltage is provided for at least a portion of the driver chips of the display panel.

9. The display device according to claim 8, characterized in that, The display panel includes: Gate driver chip, provides gate drive data; Source driver chip, providing source driver data; and The array substrate displays a screen based on the source drive data and the gate drive data. The power supply for the source driver chip is provided by the supply voltage.

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