Source driver circuit

Abstract

This application discloses a source drive circuit, characterized in that it comprises: a bias circuit for outputting multiple reference currents; multiple current-to-voltage circuits, wherein each of the multiple current-to-voltage circuits receives one of the multiple reference currents and transmits multiple bias power supplies through multiple lines of a bias power supply bus according to the current values ​​of the received multiple reference currents; and multiple sets of operational amplifier circuits, wherein each set of operational amplifier circuits receives the multiple bias power supplies transmitted by the bias power supply bus corresponding to one of the multiple current-to-voltage circuits, wherein the output of each of the multiple sets of operational amplifier circuits corresponds to one of the source lines of multiple transistors.

Description

Technical Field

[0001] The present application belongs to the field of drive circuits and relates to a source drive circuit for a liquid crystal display screen. Background Art

[0002] Please refer to Figure 1 , which is a block diagram of a conventional liquid crystal display screen 100. In order to control the liquid crystal display 110, the liquid crystal display screen 100 includes a gate driving circuit 120 and a source driving circuit 130. The source driving circuit includes a plurality of operational amplifier circuits, which are respectively used to drive the sources of the plurality of thin film transistors of the liquid crystal display 110.

[0003] Please refer to Figure 2 , which is a circuit diagram of an existing source driving circuit 130. When the size of the above-mentioned liquid crystal display 110 becomes larger and larger, and its resolution becomes higher and higher, the source driving circuit 130 needs more and more channels, that is, more and more operational amplifier circuits 230 are required. Figure 2 There are N operational amplifier circuits 230-1 to 230-N shown, where N is a positive integer. The value of N is usually hundreds or thousands. Each operational amplifier circuit 230 requires Y bias power supplies, where Y is a positive integer greater than 1. In a typical operational amplifier circuit 230, 7 or 8 bias power supplies may be required.

[0004] The bias circuit 210 is connected to the current-to-voltage circuit 220 through the bias current line 214. The current-to-voltage circuit 220 then converts the current of the bias current line 214 into a corresponding bias current. Figure 2 The current-to-voltage circuit 220 shown provides Y bias power supply lines to N operational amplifier circuits 230-1 to 230-N, respectively. The bias power supply bundle 240-1 of the first operational amplifier circuit 230-1 and the current-to-voltage circuit 220 includes Y lines. Similarly, the bias power supply bundle 240-N of the Nth operational amplifier circuit 230-N and the current-to-voltage circuit 220 includes Y lines. These bias power supply bundles 240-N must be arranged within the frame 250 on one side of the liquid crystal display screen 100.

[0005] Due to the aesthetic design requirement, when the frame 250 of the liquid crystal display 110 becomes narrower and narrower, Y x N bias power lines must be inserted into the frame 250. Even if the current-to-voltage circuit 220 is placed in the middle of the liquid crystal display 110, Y x N / 2 bias power lines must be inserted in the middle of the frame 250. It is quite difficult to insert thousands of bias power lines into the narrow frame 250.

[0006] Since multiple bias power supply lines are squeezed in the frame 250, electromagnetic interference may occur between them. Moreover, the lengths of these bias power supply lines are different. Since the bias voltages of all N bias power supply beams 240 provided by the current-to-voltage circuit 220 are the same, but the bias voltage will decay and decrease with the length of the line, resulting in the operational amplifier circuits 230-1 and 230-N at the beginning and the end and the operational amplifier circuit 230-(N / 2) in the middle receiving inconsistent bias voltages. As a result, the driving charging time of the thin film transistor of the liquid crystal display 110 may produce errors, resulting in abnormal display.

[0007] In summary, there is an urgent need for a design of the source driver circuit 130 that can reduce the number of circuits within the frame of the liquid crystal display screen 100, so as to reduce the electromagnetic interference between each other and further narrow the frame. Furthermore, it can also reduce the voltage attenuation caused by the different lengths of the circuits, so as to make the display content of the liquid crystal display 110 more uniform. Summary of the invention

[0008] The present application is to provide a source drive circuit and a liquid crystal display screen to address the deficiencies in the prior art, with the aim of averaging the driving capability of the liquid crystal display, optimizing the arrangement of multiple circuits within the frame, narrowing the frame, and reducing the obsolescence rate of the liquid crystal display.

[0009] In order to achieve the above purpose, this application adopts the following technical solutions:

[0010] According to an embodiment of the present application, a source driver circuit is provided, characterized in that it includes: a bias circuit for outputting multiple reference currents; multiple current-to-voltage circuits, wherein each of the multiple current-to-voltage circuits receives one of the multiple reference currents, and transmits multiple bias power supplies through multiple lines of a bias power bus based on the current values ​​of the received multiple reference currents; and multiple groups of operational amplifier circuits, wherein each group of operational amplifier circuits receives the multiple bias power supplies transmitted by the bias power bus corresponding to one of the multiple current-to-voltage circuits, wherein the output of each operational amplifier circuit among the multiple groups of operational amplifier circuits corresponds to one of the source lines of a plurality of transistors.

[0011] In order to provide a circuit design proportional to absolute temperature, the source driver circuit is characterized in that the bias circuit includes one or any combination of the following circuit architectures: a bandgap reference architecture; and a constant transconductance reference current generator.

[0012] In order to provide a flexible circuit arrangement design, the above-mentioned source driver circuit is characterized in that the number of operational amplifier circuits in one group of the multiple groups of operational amplifier circuits is different from the number of operational amplifier circuits in another group of the multiple groups of operational amplifier circuits.

[0013] In order to provide a flexible driving capability arrangement, the above-mentioned source driving circuit is characterized in that the current value of the reference current received by one of the multiple current-to-voltage circuits is different from the current value of the reference current received by another current-to-voltage circuit among the multiple current-to-voltage circuits.

[0014] In order to utilize the idle space in the source driver chip, the above-mentioned source driver circuit is characterized in that some of the multiple current-to-voltage circuits are configured in the first source driver chip, and other current-to-voltage circuits are configured in the second source driver chip. The first source driver chip and the second source driver chip are located in one of the four frames of the liquid crystal display screen, and the first source driver chip and the second source driver chip are arranged parallel to one of the four frames to which they belong.

[0015] In order to provide a flexible circuit arrangement design, the above-mentioned source driver circuit is characterized in that the number of current-to-voltage circuits among the multiple current-to-voltage circuits located on the first side of the bias circuit is different from the number of current-to-voltage circuits among the multiple current-to-voltage circuits located on the second side of the bias circuit, wherein the first side is relative to the second side.

[0016] In order to coordinate with the position arrangement of the gate driving circuit, the above-mentioned source driving circuit is characterized in that the number of the current-to-voltage circuits among the plurality of current-to-voltage circuits located on the second side of the bias circuit is zero.

[0017] In order to simply set the configuration of the bias circuit, the source driving circuit is characterized in that the bias circuit is used to receive a set of setting command signals, and according to the set of setting command signals, the current values ​​of the multiple reference currents are presented as the value of a function of a position, and the position corresponds to the position of the source lines of the multiple transistors corresponding to one of the multiple operational amplifier circuits corresponding to the multiple current-to-voltage circuits. The graph of the above-mentioned function is one of the following: a straight line, a V-shape, an inverted V-shape or other shapes.

[0018] According to an embodiment of the present application, a liquid crystal display screen is provided, characterized in that it comprises: a liquid crystal display; and a source driving circuit as described above, for driving source lines of a plurality of thin film transistors of the liquid crystal display.

[0019] In order to be applicable to the source line of a defective transistor, the above-mentioned liquid crystal display screen is characterized in that the resistance value of one of the source lines of the plurality of thin film transistors exceeds its design range.

[0020] Due to the adoption of the above scheme, the beneficial effects of the present application are as follows: the source drive circuit provided by the present application can reduce the number of lines within the frame of the liquid crystal display screen, so as to reduce the phenomenon of electromagnetic interference between each other, and further narrow the frame. Furthermore, it can also reduce the voltage attenuation caused by the different lengths of the lines, average the driving capacity of each area of ​​the liquid crystal display, so as to make the display content of the liquid crystal display more uniform. For a liquid crystal display that was originally to be eliminated due to defective resistance values ​​in the source line, the source drive circuit provided by the present application can specially adjust its driving capacity according to its resistance value, which can improve the yield of the liquid crystal display. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a block diagram of a conventional liquid crystal display screen 100 .

[0022] Figure 2 is a circuit diagram of a conventional source driving circuit 130 .

[0023] Figure 3 is a block diagram of a source driving circuit 130 according to an embodiment of the present application.

[0024] Figure 4 FIG. 4 is a block diagram of a source driver chip 410 according to an embodiment of the present application.

[0025] Figure 5 This is a schematic diagram of different voltage rise curves corresponding to different current values.

[0026] Figure 6 FIG. 4 is a schematic diagram of an input / output interface of a bias circuit 310 according to an embodiment of the present application.

[0027] Figure 7 FIG. 4 is a schematic diagram of an input / output interface of a bias circuit 310 according to an embodiment of the present application.

[0028] Figure 8 Schematic diagram of a frame 350 according to an embodiment of the present application. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other implementation methods obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0030] The terms "first", "second", "third", etc. (if any) in the specification and claims of this application and the drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the objects described in these descriptions can be interchanged where appropriate. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. Some of the block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or in one or more hardware circuits or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0031] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0032] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two components or the interaction relationship between two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] In order to make the purpose, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with drawings and specific implementation methods.

[0034] Please refer to Figure 3As shown, it is a block diagram of a source driver circuit 130 according to an embodiment of the present application. The source driver circuit 130 includes a bias circuit 310 and P current-to-voltage circuits 220-1 to 220-P. In some embodiments, the bias circuit 310 may include a circuit with a bandgap reference architecture, which can provide multiple reference currents to the P current-to-voltage circuits 220-1 to 220-P respectively. In some embodiments, the bias circuit 310 may include a constant transconductance reference current generator (constant Gm / transconductance current reference generator). It can be understood by those of ordinary skill in the art that the bias circuit 310 of the present application can be applied to a circuit using a bandgap reference, a constant transconductance reference current generator circuit, or other reference current generating circuits, and the reference current generated by the circuit is independent of temperature changes.

[0035] The bias circuit 310 can dynamically adjust the current value of the reference current transmitted to the current-to-voltage circuit 220 according to the individual current-to-voltage circuits 220. For example, the current value of the reference current 314-1 transmitted to the current-to-voltage circuit 220-1 by the bias circuit 310 can be different from the current value of the reference current 314-2 transmitted to the current-to-voltage circuit 220-2 by the bias circuit 310. Of course, the current values ​​of any two reference currents can also be the same.

[0036] Since the current value of each reference current output by the bias circuit 310 can be dynamically adjusted, the present application can be preferably used to adjust the parameters and adaptability of the liquid crystal display 110 and the source driving circuit 130 .

[0037] exist Figure 3 In the illustrated embodiment, each current-to-voltage circuit 220 corresponds to Q operational amplifier circuits 230, that is, the number of operational amplifier circuits 230 corresponding to each current-to-voltage circuit 220 is the same, where Q is a positive integer. In other embodiments, the number of operational amplifier circuits 230 corresponding to each current-to-voltage circuit 220 may be inconsistent. For example, the current-to-voltage circuit 220-i may correspond to m operational amplifier circuits 230, and the current-to-voltage circuit 220-j may correspond to n operational amplifier circuits 230, where i and j are different positive integers, and m and n are also different positive integers.

[0038] In some embodiments of the present application, the thin film transistors to which the sources corresponding to the Q operational amplifier circuits 230 belong are adjacent. Figure 3As shown, the first current-to-voltage circuit 220-1 corresponds to the operational amplifier circuit 230-1-1 to the operational amplifier circuit 230-1-Q. The Q operational amplifier circuits 230-1-1 to 230-1-Q correspond to a continuous liquid crystal display area 360-1. The last current-to-voltage circuit 220-P corresponds to the operational amplifier circuit 230-P-1 to the operational amplifier circuit 230-PQ. The Q operational amplifier circuits 230-P-1 to 230-PQ correspond to a continuous liquid crystal display area 360-P. Similarly, the current-to-voltage circuit 220-i corresponds to the operational amplifier circuit 230-i-1 to the operational amplifier circuit 230-iQ. The Q operational amplifier circuits 230-1-1 to 230-1-Q correspond to a continuous liquid crystal display area 360-i, where i is a positive integer less than or equal to P.

[0039] However, for the convenience of circuit arrangement, in some embodiments of the present application, the thin film transistors corresponding to the sources of the Q operational amplifier circuits 230 may not be adjacent. For example, the thin film transistors corresponding to the operational amplifier circuits 230-1-1 to 230-1-Q may be interleaved with the thin film transistors corresponding to the operational amplifier circuits 230-2-1 to 230-2-Q. In other words, two adjacent current-to-voltage circuits 220 may correspond to the same liquid crystal display area 360.

[0040] The current-to-voltage circuit 220 can be connected to the corresponding operational amplifier circuit 230 via a bias power bus 340. Figure 3 As shown, for example, the current-to-voltage circuit 220-1 can be connected to the corresponding operational amplifier circuits 230-1-1 to 230-1-Q through a bias power bus 340-1. These bias power buses 340-1 can include Y lines. Since the operational amplifier circuits 230-1-1 to 230-1-Q are connected to the same current-to-voltage circuit 220 through the same bias power bus 340-1, and the operational amplifier circuits 230-1-1 to 230-1-Q can be adjacent, their bias power supplies should be consistent.

[0041] As mentioned in the prior art, the voltage value transmitted in the bias power bus 340 will decay with the line length. However, when the current-to-voltage circuit 220 is arranged near the corresponding Q operational amplifier circuits 230, the attenuated voltage value in the bias power bus 340 is relatively reduced.

[0042] Compared to the voltage value that attenuates with the line length, the current value of the reference current 314-1 transmitted by the bias circuit 310 to each current-to-voltage circuit 220 does not change due to the line length. In other words, even if P current-to-voltage circuits 220 are evenly arranged on the border of the liquid crystal display screen 100, the current value of the reference current received by each current-to-voltage circuit 220 will not change due to its different position.

[0043] In some embodiments of the present application, the bias circuit 310 is located in the center of the frame of the liquid crystal display screen 100 to shorten the total length of all reference current lines 314. However, since the current value of the reference current does not change due to the line length, the present application does not limit the bias circuit 310 to be located in the center of the frame of the liquid crystal display screen 100. For example, the bias circuit 310 can be arranged near the power supply line or in a suitable space, and is not limited to the center of the frame of the liquid crystal display screen 100. In some embodiments, the bias circuit 310 is located on one side of the frame of the liquid crystal display screen 100 so as to be close to the gate drive circuit 120.

[0044] Therefore, in the embodiment provided by the present application, each current-to-voltage circuit 220 can be arranged as close as possible to its corresponding liquid crystal display area 360, so that its corresponding bias power bus 340 is as short as possible, without having to cross a large part of the side length of the liquid crystal display, thereby greatly reducing the attenuation of the bias voltage value of its corresponding Q operational amplifier circuits 230. In addition, since the bias voltage values ​​of the adjacent Q operational amplifier circuits 230 are the same, the electromagnetic interference within the same bias power bus 340 is also minimized.

[0045] exist Figure 3 In the embodiment shown, since the length of the bias power bus 340 is shortened, part of the originally arranged lines is changed from Y lines to a reference current line 314, so the number and density of lines arranged inside the frame 350 can be greatly reduced. In this way, the frame can be further narrowed, and the design of the liquid crystal display screen 100 can be beautified.

[0046] In the existing source driver circuit design, a plurality of source driver chips 410 are usually included and arranged inside the frame 350. These source driver chips 410 are arranged one by one along the frame 350 and are respectively connected to the source of the thin film transistor of the liquid crystal display 110. However, the existing source driver chip 410 is usually designed as a rectangle, and there is some idle space inside where no working circuits are arranged. An inventive feature of the present application is to design the aforementioned current-to-voltage circuit 220 into the idle space of these source driver chips 410, so that it can be close to the corresponding Q operational amplifier circuits 230, and will not occupy additional space in the frame 350.

[0047] Please refer to Figure 8 As shown, it is a schematic diagram of the frame 350 according to an embodiment of the present application. The aforementioned bias circuit 310 and other control circuits can be arranged near the center line 810 of the frame 350. The center line 810 of the frame 350 divides the frame 350 into left and right sides. A plurality of source driver chips 410 are arranged in the frame 350. For example Figure 8 As shown, four source driver chips 410 - 1 to 410 - 4 are arranged on the left side. Similarly, four source driver chips 410 - 5 to 410 - 8 are arranged on the right side.

[0048] The left side and the right side are roughly divided into four equal parts. When the direction is from left to right, the positions of the source driver chips 410-1 to 410-4 are approximately zero quarter, one quarter, two quarters and three quarters on the left side. The positions of the source driver chips 410-5 to 410-8 are approximately one quarter, two quarters, three quarters and four quarters on the right side. It can be understood by those skilled in the art that although Figure 8 An embodiment of four-division is shown, but the embodiment can be applicable to a frame 350 divided into N equal parts, where N is a positive integer greater than 1.

[0049] A person skilled in the art can understand that the present application can design all current-to-voltage circuits 220 into the idle space of these source driver chips 410 , but can also design part of the current-to-voltage circuits 220 into the idle space of these source driver chips 410 .

[0050] Please refer to Figure 4 As shown, it is a block diagram of a source driver chip 410 according to an embodiment of the present application. The original circuit 420 included in the source driver chip 410 does not occupy all the area of ​​the source driver chip 410, and the remaining idle chip area can realize multiple current-to-voltage circuits 220. Figure 4In the embodiment shown, these current-to-voltage circuits 220 are usually arranged at two ends of the chip. Those skilled in the art will understand that the present application does not limit the location of the current-to-voltage circuit 220 in the chip, nor does it limit the number of the current-to-voltage circuit 220 in the chip.

[0051] Please refer to Figure 5 , which is a schematic diagram of different voltage climbing curves corresponding to different current values. When the bias circuit 310 supplies different reference current values ​​to different current-to-voltage circuits 220, the voltage climbing rate of the corresponding operational amplifier circuit 230 can be adjusted. In some embodiments of the present application, the current value of the reference current given by the bias circuit 310 to a certain current-to-voltage circuit 220 corresponds to the driving capability of the liquid crystal display area 360 corresponding to the current-to-voltage circuit 220.

[0052] In some embodiments, the manufacturer of the liquid crystal display 110 does not modify the resistance value of the source circuit of each thin film transistor according to the defects mentioned above. Therefore, the source driving circuit 130 provided in the present application can make the bias circuit 310 output the current value of the corresponding reference current to the current-to-voltage circuit 220 corresponding to each liquid crystal display area 360 according to the driving capability required by each liquid crystal display area 360.

[0053] In other embodiments, the manufacturer of the liquid crystal display 110 has taken into account the aforementioned defects and modified the resistance value of the source circuit of a portion of the thin film transistors to overcome the driving capability variation caused by the different distances of the bias power beam 240. For example, the resistance value of the source circuit of the thin film transistor in the middle of the liquid crystal display 110 can be higher than the resistance value of the source circuit of the thin film transistor at the edge of the liquid crystal display 110.

[0054] Similarly, the source driving circuit 130 provided in the present application can make the bias circuit 310 output the current value of the corresponding reference current to the current-to-voltage circuit 220 corresponding to each liquid crystal display area 360 according to the driving capability required by each liquid crystal display area 360. In the above example, the bias circuit 310 can output a higher current value of the reference current to the current-to-voltage circuit 220 corresponding to the middle of the liquid crystal display 110 to overcome the higher resistance value of the source circuit. At the same time, a lower current value of the reference current is output to the current-to-voltage circuit 220 corresponding to the edge of the liquid crystal display 110 to adapt to the lower resistance value of the source circuit. In this way, the driving capability required by each liquid crystal display area 360 can be set evenly.

[0055] In some embodiments, defects occur in the liquid crystal display 110 during the manufacturing process, causing the resistance value of the source circuit of a portion of the thin film transistors to be different from the design value. The source drive circuit 130 of the prior art cannot be applied to these defective liquid crystal displays 110, so these defective liquid crystal displays 110 must be destroyed, increasing the manufacturer's cost. The source drive circuit 130 provided in the present application can adjust the current value of the reference current of the corresponding current-to-voltage circuit 220 according to the resistance value of these defective source circuits, so that the operational amplifier circuit 230 corresponding to these defective source circuits can adapt to different defects. Accordingly, the cost of the liquid crystal display 110 that was originally to be destroyed can be saved.

[0056] Please refer to Figure 6 As shown, it is a schematic diagram of the input and output interface of the bias circuit 310 according to a certain embodiment of the present application. Figure 6 As shown, the bias circuit 310 includes outputs of P reference current lines 314-1 to 314-P, which are respectively connected to P current-to-voltage circuits 220-1 to 220-P. Corresponding to each current-to-voltage circuit 220-1 to 220-P, the bias circuit 310 also has P groups of reference current value input signals 610-1 to 610-P. Each group of reference current value input signals 610 has w digital logic signal lines, where w can be a positive integer greater than one. Accordingly, the reference current has 2 w For example, when the w value is 3, the reference current has 8 possible settings.

[0057] Among the multiple set values, one set value may be a preset reference current value. After the bias circuit 310 starts working, if no reference current value input signal 610 is received, the preset reference current value may be output to the corresponding current-to-voltage circuit 220. When the reference current value input signal 610 is received, the reference current value corresponding to the reference current input signal value may be output to the corresponding current-to-voltage circuit 220.

[0058] Please refer to Figure 7 , which is a schematic diagram of the input and output interface of the bias circuit 310 according to an embodiment of the present application. Figure 6 The illustrated embodiments are similar in that the bias circuit 310 includes outputs of P reference current lines 314 connected to the P current-to-voltage circuits 220 - 1 to 220 -P, respectively.

[0059] The bias circuit 310 includes a reference current value input signal 710, which has w signal lines, where w can be a positive integer greater than 1. wFor example, when the value of w is 3, the reference current has 8 possible setting values. The bias circuit 310 also includes a set of current-to-voltage circuit address signals 720, which has u address lines, where u can be a positive integer greater than one, where 2 u It must be greater than P to specify any one of the current-to-voltage circuits 220 - 1 to 220 -P.

[0060] When the reference current value of a current-to-voltage circuit 220 is to be set, the current-to-voltage circuit address signal 720 can be used to specify a current-to-voltage circuit 220 when the bias circuit 310 is operating, and the reference current value input signal 710 can be used to set the reference current value. Figure 6 Compared with the embodiment shown in the figure, when the value of P increases, Figure 7 The illustrated embodiment can save the number of input signals to the bias circuit 310 .

[0061] Figure 7 The bias circuit 310 shown may also include a set of setting command signals 730. The set of setting command signals 730 includes v signal lines, where v can be a natural number. The set of setting command signals 730 may be used to input a command of a specific configuration to comprehensively adjust the output of the P reference current lines 314 at one time. For example, the set of setting command signals 730 may be used to input an average output command so that the outputs of the P reference current lines 314 all have the same reference current value. The set of setting command signals 730 may be used to input a default output command so that the outputs of the P reference current lines 314 all have a preset reference current value.

[0062] The set command signal 730 can be used to input a V-type output command, so that the reference current value of the output of the P-root reference current line 314 presents a configuration from high to low and then from low to high. Conversely, the set command signal 730 can be used to input an inverted V-type output command, so that the reference current value of the output of the P-root reference current line 314 presents a configuration from low to high and then from high to low. It can be understood by a person of ordinary skill in the art that the above-mentioned V-type or inverted V-type is only a general description. The input command can be one or more linear functions to describe the function composed of the reference current values ​​of all P-root reference current lines 314, or it can be one or more nonlinear functions, such as a quadratic function, to describe the function composed of the reference current values ​​of all P-root reference current lines 314.

[0063] According to an embodiment of the present application, a source driver circuit is provided, characterized in that it includes: a bias circuit for outputting multiple reference currents; multiple current-to-voltage circuits, wherein each of the multiple current-to-voltage circuits receives one of the multiple reference currents, and transmits multiple bias power supplies through multiple lines of a bias power bus based on the current values ​​of the received multiple reference currents; and multiple groups of operational amplifier circuits, wherein each group of operational amplifier circuits receives the multiple bias power supplies transmitted by the bias power bus corresponding to one of the multiple current-to-voltage circuits, wherein the output of each operational amplifier circuit among the multiple groups of operational amplifier circuits corresponds to one of the source lines of a plurality of transistors.

[0064] In order to provide a circuit design proportional to absolute temperature, the source driver circuit is characterized in that the bias circuit includes one or any combination of the following circuit architectures: a bandgap reference architecture; and a constant transconductance reference current generator.

[0065] In order to provide a flexible circuit arrangement design, the above-mentioned source driver circuit is characterized in that the number of operational amplifier circuits in one group of the multiple groups of operational amplifier circuits is different from the number of operational amplifier circuits in another group of the multiple groups of operational amplifier circuits.

[0066] In order to provide a flexible driving capability arrangement, the above-mentioned source driving circuit is characterized in that the current value of the reference current received by one of the multiple current-to-voltage circuits is different from the current value of the reference current received by another current-to-voltage circuit among the multiple current-to-voltage circuits.

[0067] In order to utilize the idle space in the source driver chip, the above-mentioned source driver circuit is characterized in that some of the multiple current-to-voltage circuits are configured in the first source driver chip, and other current-to-voltage circuits are configured in the second source driver chip. The first source driver chip and the second source driver chip are located in one of the four frames of the liquid crystal display screen, and the first source driver chip and the second source driver chip are arranged parallel to one of the four frames to which they belong.

[0068] In order to provide a flexible circuit arrangement design, the above-mentioned source driver circuit is characterized in that the number of current-to-voltage circuits among the multiple current-to-voltage circuits located on the first side of the bias circuit is different from the number of current-to-voltage circuits among the multiple current-to-voltage circuits located on the second side of the bias circuit, wherein the first side is relative to the second side.

[0069] In order to coordinate with the position arrangement of the gate driving circuit, the above-mentioned source driving circuit is characterized in that the number of the current-to-voltage circuits among the plurality of current-to-voltage circuits located on the second side of the bias circuit is zero.

[0070] In order to simply set the configuration of the bias circuit, the source driving circuit is characterized in that the bias circuit is used to receive a set of setting command signals, and according to the set of setting command signals, the current values ​​of the multiple reference currents are presented as the value of a function of a position, and the position corresponds to the position of the source lines of the multiple transistors corresponding to one of the multiple operational amplifier circuits corresponding to the multiple current-to-voltage circuits. The graph of the above-mentioned function is one of the following: a straight line, a V-shape, an inverted V-shape or other shapes.

[0071] According to an embodiment of the present application, a liquid crystal display screen is provided, characterized in that it comprises: a liquid crystal display; and a source driving circuit as described above, for driving source lines of a plurality of thin film transistors of the liquid crystal display.

[0072] In order to be applicable to the source line of a defective transistor, the above-mentioned liquid crystal display screen is characterized in that the resistance value of one of the source lines of the plurality of thin film transistors exceeds its design range.

[0073] In summary, the source drive circuit provided by the present application can reduce the number of lines within the frame of the liquid crystal display screen, so as to reduce the phenomenon of electromagnetic interference between each other, and further narrow the frame. Furthermore, it can also reduce the voltage attenuation caused by the different lengths of the lines, average the driving capacity of each area of ​​the liquid crystal display, so as to make the display content of the liquid crystal display more uniform. For a liquid crystal display that was originally to be eliminated due to defective resistance values ​​in the source line, the source drive circuit provided by the present application can specially adjust its driving capacity according to its resistance value, which can improve the yield of the liquid crystal display.

[0074] The above is only a preferred specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or changes within the technical scope disclosed in the present application according to the technical solution and application concept of the present application, which should be covered by the protection scope of the present application.

Claims

1. A source driving circuit, characterized in that: Include: A bias circuit for outputting a plurality of reference currents; a plurality of current-to-voltage circuits, wherein each of the plurality of current-to-voltage circuits receives one of the plurality of reference currents and transmits a plurality of bias power supplies through a plurality of lines of a bias power supply bus according to current values ​​of the received plurality of reference currents; as well as A plurality of operational amplifier circuits, each of which receives the plurality of bias power supplies transmitted by the bias power bus corresponding to one of the plurality of current-to-voltage circuits, The bias power supplies received by the adjacent multiple operational amplifier circuits in the same group are the same. The output of each operational amplifier circuit among the plurality of operational amplifier circuits corresponds to one of the source lines of the plurality of transistors.

2. The source driving circuit according to claim 1, wherein: The bias circuit mentioned above includes one or any combination of the following circuit structures: a bandgap reference structure; and a constant Gm (transconductance current reference generator).

3. The source driving circuit according to claim 1, wherein: The number of operational amplifier circuits in one group of the plurality of operational amplifier circuits is different from the number of operational amplifier circuits in another group of the plurality of operational amplifier circuits.

4. The source driving circuit according to claim 1, wherein: The current value of the reference current received by one of the multiple current-to-voltage circuits is different from the current value of the reference current received by another current-to-voltage circuit of the multiple current-to-voltage circuits.

5. The source driving circuit according to claim 1, wherein: Some of the multiple current-to-voltage circuits are configured in a first source driver chip, and other current-to-voltage circuits are configured in a second source driver chip. The first source driver chip and the second source driver chip are located in one of the four frames of the liquid crystal display screen, and the first source driver chip and the second source driver chip are arranged parallel to one of the four frames to which they belong.

6. The source driving circuit according to claim 1, wherein: The number of current-to-voltage circuits among the multiple current-to-voltage circuits located on a first side of the bias circuit is different from the number of current-to-voltage circuits among the multiple current-to-voltage circuits located on a second side of the bias circuit, wherein the first side is relative to the second side.

7. The source driving circuit according to claim 6, wherein: The number of the current-to-voltage circuits of the plurality of current-to-voltage circuits located on the second side of the bias circuit is zero.

8. The source driving circuit according to claim 1, wherein: The bias circuit is used to receive a set of setting command signals, and according to the set of setting command signals, the current values ​​of the multiple reference currents are presented as the value of a function of a position, and the position corresponds to the position of the source lines of the multiple transistors corresponding to one of the multiple sets of operational amplifier circuits corresponding to the multiple current-to-voltage circuits.

9. The source driving circuit according to claim 8, wherein: The graph of the above function is one of the following: a straight line, a V-shape, an inverted V-shape or other shapes.

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