This application is a US National Phase application based upon International Application No. PCT/CN2022/105034, filed on Jul. 12, 2022, which claims priority benefit to Chinese Patent Application No. 202210717722.3 filed on Jun. 23, 2022, titled “DEMULTIPLEXER AND DRIVING METHOD THEREOF, AND DISPLAY PANEL HAVING DEMULTIPLEXER”, the entire contents of which are hereby incorporated by reference in its entirety in this application.
The present application relates to a field of display technology, and more specifically, to a demultiplexer and a driving method thereof, and a display panel having the demultiplexer.
With a continuous increase in size and resolution of a display panel, when each output channel of source driver integrated circuits (IC) is connected to each data line of the display panel one-to-one, there is a problem of increased costs due to an increased number of source driver ICs. Therefore, in order to reduce a number of source driver ICs, a demultiplexer (DEMUX) is disposed between the source driver ICs and data lines in a non-display region of the display panel and configured to input data signals to a plurality of data lines by time-division of one output channel of the source driver ICs, thereby reducing a number of data driver ICs and reducing costs.
As shown in
In view of this, as shown in
Specifically, in conjunction with
The 1:K DEMUX circuit shown in
Therefore, there is an urgent need for a new demultiplexer that can reduce the size and power consumption by reducing a number of MUX control signals and TFTs, and at a same time, achieving better display uniformity on the display panel.
To solve the foregoing problems, embodiments of the present application provide a demultiplexer and a driving method thereof, and a display panel having the demultiplexer.
In a first aspect, an embodiment of the present application provides a demultiplexer including:
In some embodiments, a source of the switching transistor is connected to the output channel, a drain of the switching transistor is connected to a data line, and a capacitance value of the coupling capacitance is same as a capacitance value of a gate-source parasitic capacitance of the switching transistor or a capacitance value of a gate-drain parasitic capacitance of the switching transistor.
In some embodiments, a source of the switching transistor is connected to a data line, a drain of the switching transistor is connected to the output channel, and a capacitance value of the coupling capacitance is same as a capacitance value of a gate-source parasitic capacitance of the switching transistor or a capacitance value of a gate-drain parasitic capacitance of the switching transistor.
In some embodiments, the demultiplexer further comprises a coupling capacitance control signal line, and the N metal electrode plates are all connected to the coupling capacitance control signal line.
In a second aspect, an embodiment of the present application also provides a method for driving a demultiplexer includes following steps of:
In some embodiments, the step S1 specifically includes following steps of:
In some embodiments, the step S2 specifically includes following steps of:
In some embodiments, the demultiplexer comprises:
In some embodiments, a source of the switching transistor is connected to the output channel, a drain of the switching transistor is connected to a data line, and a capacitance value of the coupling capacitance is same as a capacitance value of a gate-source parasitic capacitance of the switching transistor or a capacitance value of a gate-drain parasitic capacitance of the switching transistor.
In some embodiments, a source of the switching transistor is connected to a data line, a drain of the switching transistor is connected to the output channel, and a capacitance value of the coupling capacitance is same as a capacitance value of a gate-source parasitic capacitance of the switching transistor or a capacitance value of a gate-drain parasitic capacitance of the switching transistor.
In some embodiments, the demultiplexer further comprises a coupling capacitance control signal line, and the N metal electrode plates are all connected to the coupling capacitance control signal line.
In a third aspect, an embodiment of the present application further provides a display panel, including a source driver, N*K data lines, and the demultiplexer as described above, which are connected in sequence, wherein the source driver uses a time-division method to input data signals to corresponding K data lines through each output channel of the demultiplexer;
In some embodiments, the display panel further includes a gate line and a pixel definition layer, wherein the metal electrode plates of the demultiplexer and the data lines are arranged in different layers; and the metal electrode plates are arranged in a same layer as at least one of the gate line and the pixel definition layer.
In some embodiments, the display panel further includes a coupling capacitance control signal line, and the metal electrode plates and the coupling capacitance control signal line are arranged in a same layer; or the metal electrode plates are multiplexed with the coupling capacitance control signal line.
In some embodiments, a source of the switching transistor is connected to the output channel, a drain of the switching transistor is connected to a data line, and a capacitance value of the coupling capacitance is same as a capacitance value of a gate-source parasitic capacitance of the switching transistor or a capacitance value of a gate-drain parasitic capacitance of the switching transistor.
In some embodiments, a source of the switching transistor is connected to a data line, a drain of the switching transistor is connected to the output channel, and a capacitance value of the coupling capacitance is same as a capacitance value of a gate-source parasitic capacitance of the switching transistor or a capacitance value of a gate-drain parasitic capacitance of the switching transistor.
In some embodiments, the demultiplexer further comprises a coupling capacitance control signal line, and the N metal electrode plates are all connected to the coupling capacitance control signal line.
The multiplexer and the driving method thereof, and the display panel having the multiplexer provided by embodiments of the present application, enable each output channel to input data signals to K data lines in a time-division manner, wherein each output channel is respectively connected to (K−1) data lines through (K−1) switching transistors and is directly connected to another data line; a metal electrode plate is arranged near the another data line of each output channel to form a coupling capacitance between each metal electrode plate and the another data line corresponding to each output channel. Therefore, by controlling change in potential of each metal electrode plate, the potential of the another data line changes accordingly based on the coupling capacitance, so that a feedthrough effect on the another data line corresponding to each output channel is close to that on other (K−1) data lines, and brightness of a pixel unit controlled by the another data line corresponding to each output channel is approximately same as that of a plurality of pixel units controlled by other (K−1) data lines, thereby reducing size and power consumption of the DEMUX circuit, and at a same time, achieving better display uniformity on the display panel.
To make the objectives, technical solutions, and advantages of this application clearer, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that specific embodiments described herein are used for explaining this application, but not used for limiting this application.
With reference to
It should be noted that, in
Specifically, a working principle of the demultiplexer is that: each output channel inputs data signals to K data lines in a time-division manner, wherein each output channel is connected to (K−1) data lines (e.g., a first data line to a (K−1)th data line) through (K−1) switching transistors respectively, and is directly connected to the another data line (e.g., a Kth data line). A metal electrode plate is arranged near the another data line of each output channel to form a coupling capacitance between each output channel and the metal electrode plate nearby to the output channel, and a potential of the another data line changes accordingly through a potential change of the coupling capacitance, this reduces a difference between a feedthrough effect of the another data line corresponding to each output channel and a feedthrough effect of other (K−1) data lines, thus reducing a difference between brightness of a pixel unit controlled by the another data line corresponding to each output channel and brightness of a plurality of pixel units controlled by the other (K−1) data lines, and improving a display uniformity of the display panel.
Compared with a traditional DEMUX circuit shown in
The demultiplexer further includes a coupling capacitance control signal line CUX, and the N metal electrode plates are all connected to the coupling capacitance control signal line CUX, and potentials of the N metal electrode plates may be controlled uniformly through the coupling capacitance control signal line CUX.
It should be noted that the metal electrode plate can be provided so that a capacitance value of the coupling capacitance formed between the metal electrode plate and the another data line corresponding to each output channel is as much the same as the capacitance value of a gate-source parasitic capacitance Cgs or a gate-drain parasitic capacitance Cgd of the switching transistor, so that the another data line corresponding to each output channel is subjected to same feedthrough effects as the other (K−1) data lines. This results in essentially no difference in brightness between the pixel unit controlled by the another data line and the plurality of pixel units controlled by the other (K−1) data lines.
It can be understood that an area of the metal electrode plate and a spacing between the metal electrode plate and the another data line corresponding to each output channel are adjustable, so that the capacitance value of the coupling capacitance is equal to that of the gate-source parasitic capacitance Cgs or the gate-drain parasitic capacitance Cgd of the switching transistor by adjusting the capacitance value of the coupling capacitance.
Wherein, in some embodiments, a source of the switching transistor is connected to the output channel, a drain of the switching transistor is connected to a data line, and the capacitance value of the coupling capacitance is same as the capacitance value of the gate-source parasitic capacitance of the switching transistor or the capacitance value of the gate-drain parasitic capacitance of the switching transistor. Alternatively, in some embodiments, the source of the switching transistor is connected to the data line, the drain of the switching transistor is connected to the output channel, and the capacitance value of the coupling capacitance is same as the capacitance value of the gate-source parasitic capacitance of the switching transistor or the capacitance value of the gate-drain parasitic capacitance of the switching transistor.
Specifically, the coupling capacitance formed by the another data line corresponding to each output channel and the metal electrode plate is configured to couple a potential of the another data line, and the coupling capacitance is equal to a parasitic capacitance of the switching transistor connected to the other (K−1) data lines, so that when the source of the switching transistor is connected to the data line, the coupling capacitance is same as the gate-source parasitic capacitance Cgs of the switching transistor or the gate-drain parasitic capacitance Cgd of the switching transistor, and when the drain of the switching transistor is connected to the data line, the coupling capacitance is same as the gate-source parasitic capacitance Cgs of the switching transistor or the gate-drain parasitic capacitance Cgd of the switching transistor, so that the feedthrough effect on the another data line corresponding to each output channel is substantially same as that on the other (K−1) data lines, and thus the pixel unit controlled by the another data line corresponding to each output channel has substantially same brightness as the plurality of pixel units controlled by the other (K−1) data lines.
Based on the foregoing embodiments, as shown in
Further, the display panel further comprises a gate line Gate and a pixel definition layer PXL, wherein the metal electrode plate C of the multiplexer and the data lines Data are arranged in different layers; the metal electrode plate C is arranged in a same layer as at least one of the gate line Gate and the pixel definition layer.
Further, the display panel further includes a coupling capacitance control signal line, the metal electrode plate C and the coupling capacitance control signal line CUX are arranged in a same layer; alternatively, the metal electrode plate C is multiplexed with the coupling capacitance control signal line (as CUX/C in
Specifically, the metal electrode plate C is arranged in a same layer as the coupling capacitance control signal line CUX, and is arranged in different layers to the data line Data, that is, the metal electrode plate C may be part of the coupling capacitance control line CUX, and an insulating layer is disposed between the metal electrode plate C and the data line Data, such that a coupling capacitance is formed between the metal electrode plate C and the data line Data.
In some embodiments, as shown in
In some embodiments, the metal electrode plate C and the coupling capacitance control signal line CUX are arranged in a same layer as the gate line Gate, or the metal electrode plate C and the coupling capacitance control signal line CUX are arranged in the pixel definition layer.
Specifically, as shown in
Alternatively, as shown in
Alternatively, as shown in
It should be noted that in
Based on the foregoing embodiments, in conjunction with
In some embodiments, the step S1 specifically includes following steps of:
In some embodiments, the step S2 specifically includes following steps of:
Specifically, each line scan cycle consists of K periods in sequence. At the first period, MUX1 provides high level, MUX2-MUX(K−1) provide low level, CH1 inputs a data signal to D11 via T11 and directly inputs a data signal to D1K, CH2 inputs a data signal to D21 via T21 and directly inputs a data signal to D2K, . . . , CH(N) inputs a data signal to DN1 via TN1 and directly inputs a data signal to DNK; at the second period, MUX2 provides high level, MUX1, MUX3-MUX(K−1) provide low level, CH1 inputs a data signal to D12 via T12 and directly inputs a data signal to D1K, CH2 inputs a data signal to D22 via T22 and directly inputs a data signal to D2K, . . . , CH(N) inputs a data signal to DN2 via TN2 and directly inputs a data signal to DNK, and so on, at a (K−1)th period, MUX(K−1) provides high level, MUX1-MUX(K−2) provide low level, CH1 inputs a data signal to D1(K−1) via T1(K−1) and directly inputs a data signal to D1K, CH2 inputs a data signal to D2(K−1) via T2(K−1) and directly inputs a data signal to D2K, . . . , CH(N) inputs a data signal to DN(K−1) via TN(K−1) and directly inputs a data signal to DNK; at a Kth period, MUX1-MUX(K−1) provide low level, CUX provides high level, CH1 directly inputs a data signal to D1K, CUX couples a potential of D1K via C1K. CH2 directly inputs a data signal to D2K, CUX couples a potential of D2K via C2K, . . . , CH(N) directly inputs a data signal to DNK, and CUX couples a potential of DNK via CNK.
That is, from the first period to the (K−1)th period of each line scan cycle, MUX1-MUX(K−1) provide high levels in sequence, and each output channel respectively inputs data signals to the corresponding first data line to the corresponding (K−1)th data line, and inputs a data signal to the another data line corresponding to each output channel, i.e., a Kth data line. At the Kth period, MUX1-MUX(K−1) all provide low levels, the coupling capacitance control signal line CUX provides high level, and each output channel only inputs a data signal to the another data line corresponding to each output channel, i.e., the Kth data line, thus forming a finally displayed image for each frame. Wherein at the Kth period, when the coupling capacitance control signal is on a rising edge from the low level to the high level, the coupling capacitance formed by the another data line corresponding to each output channel and the metal electrode plate causes a potential of the Kth data line to rise; when the coupling capacitance control signal is on a falling edge from the high level to the low level, the coupling capacitance formed by the another data line corresponding to each output channel and the metal electrode plate causes the potential of the Kth data line to fall, so that a feedthrough effect on the Kth data line is substantially same as that on the other (K−1) data lines, and brightness of a pixel unit controlled by the Kth data line is same as brightness of a plurality of pixel units controlled by the other (K−1) data lines, thus improving display uniformity of the display panel.
It should be noted that the another data line corresponding to each output channel may be any one of the K data lines input a data signal by each output channel in a time-division manner. However, it should be noted that, since the data signal received by the another data line need to be received at a last period to enable the pixel unit controlled by the another data line to realize the finally displayed image corresponding to the data signal received at the last period, each output channel should only input a data signal to the another data line, while no data signal is input to any of the other (K−1) data lines at the last period.
Based on the foregoing embodiments, as shown in
Specifically, at the first period of each line scan cycle, MUX1 provides high level, MUX2 and CUX provide low level, T1 and T2 are turned on, CH1 inputs a data signal to D1 via T1 and directly inputs a data signal to T5, and CH2 inputs a data signal to D2 via T2 and directly inputs a data signal to T6; at the second period of each line scan cycle, MUX2 provides high level, MUX1 and CUX provide low level, CH1 inputs a data signal to D3 via T3 and directly inputs a data signal to D5, CH2 inputs a data signal to D4 via T4 and directly inputs a data signal to D6; at the third period of each line scan cycle, MUX1 and MUX2 provide low level, CUX provides high level, CH1 directly inputs a data signal to D5 and CH2 directly inputs a data signal to D6. At this time, when CUX is converted from low level to high level, the coupling effect of C1 causes a potential of D5 to rise and the coupling effect of C2 causes a potential of D6 to rise, while when CUX is converted from high level to low level, the coupling effect of C1 causes the potential of D5 to fall and the coupling effect of C2 causes the potential of D6 to fall, that is, so that D5 and D6 and D1, D2, D3, and D4 are subject to essentially no difference in the feedthrough effects, and the pixel units controlled by D5 and D6 have essentially same brightness as the pixel units controlled by D1, D2, D3, and D4, thereby improving the display uniformity of the display panel.
It should be noted that present application is not limited to the exemplary examples. Those skilled in the art in the art may achieve equivalent improvements or replacements according to the above description. The equivalent improvements and replacements should be considered to belong to the protection scope of the present application.
Number | Date | Country | Kind |
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202210717722.3 | Jun 2022 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2022/105034 | 7/12/2022 | WO |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2023/245754 | 12/28/2023 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
7742021 | Shin | Jun 2010 | B2 |
9741306 | Kim | Aug 2017 | B2 |
9754537 | Lee | Sep 2017 | B2 |
11195484 | Li | Dec 2021 | B2 |
20100117939 | Lee | May 2010 | A1 |
20110169018 | Hsiao et al. | Jul 2011 | A1 |
20160171924 | Kim et al. | Jun 2016 | A1 |
20170309230 | Kwon | Oct 2017 | A1 |
20200020296 | Kim | Jan 2020 | A1 |
20200111420 | Yang | Apr 2020 | A1 |
20240071331 | Tao | Feb 2024 | A1 |
Number | Date | Country |
---|---|---|
103744209 | Apr 2014 | CN |
109448631 | Mar 2019 | CN |
109634010 | Apr 2019 | CN |
20080000361 | Jan 2008 | KR |
20200129609 | Nov 2020 | KR |
Entry |
---|
International Search Report in International application No. PCT/CN2022/105034, mailed on Dec. 21, 2022. |
Written Opinion of the International Search Authority in International application No. PCT/CN2022/105034, mailed on Dec. 21, 2022. |
Number | Date | Country | |
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20240194111 A1 | Jun 2024 | US |