TWI811066B - Elimination circuit of LED display, LED driver chip and LED display device - Google Patents
Elimination circuit of LED display, LED driver chip and LED display device Download PDFInfo
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Abstract
一種LED顯示器之消影電路,其包括:一共用放大器,具有一電壓輸出端以輸出一消影電壓;以及複數個開關,耦接於該電壓輸出端與複數個電流源輸出端之間,係對應地受複數個開關信號之控制,且該些電流源輸出端係用以與一LED陣列耦接;於操作時,當一被選定的所述電流源輸出端被禁能,一對應之所述開關信號會呈現作用狀態以導通一對應之所述開關以為該被選定的所述電流源輸出端提供該消影電壓,從而為該LED陣列提供一消影功能。A disappearing circuit of an LED display, which includes: a common amplifier with a voltage output terminal to output a disappearing voltage; and a plurality of switches, coupled between the voltage output terminal and a plurality of current source output terminals, are Correspondingly controlled by a plurality of switch signals, and these current source output terminals are used to couple with an LED array; during operation, when a selected current source output terminal is disabled, a corresponding The switch signal is active to turn on a corresponding switch to provide the blanking voltage to the selected output terminal of the current source, thereby providing a blanking function for the LED array.
Description
本發明係有關於LED驅動電路,特別是關於一種LED顯示器之消影電路。The invention relates to an LED drive circuit, in particular to a shadow erasing circuit for an LED display.
為解決LED顯示器的殘影問題,一般的LED驅動晶片會在各電流輸出通道設置一消影電路。請參照圖1,其繪示一現有LED驅動晶片之一電流輸出通道之電路圖。如圖1所示,一電流輸出通道11具有一第一NMOS(N型金氧半)電晶體11a、一第二NMOS(N型金氧半)電晶體11b、一第一放大器11c及一第二放大器11d。In order to solve the afterimage problem of the LED display, a general LED driver chip is provided with an image elimination circuit on each current output channel. Please refer to FIG. 1 , which shows a circuit diagram of a current output channel of a conventional LED driver chip. As shown in Figure 1, a
第一NMOS電晶體11a係依一控制電壓V
B1產生一恒定電流;第二NMOS電晶體11b係作為電流輸出通道11的開關以控制是否輸出電流至一LED像素單元;第一放大器11c係依一控制電壓V
B2設置第一NMOS電晶體11a的汲極電壓及第二NMOS電晶體11b的閘極電壓以控制第二NMOS電晶體11b之開、關;以及第二放大器11d係充當一消影電路,用以依一控制電壓V
B3設置輸出通道11關閉時的消影電壓以進行一消影操作,亦即,在輸出通道11關閉時拉高輸出端OUT的電壓以將該LED像素單元的驅動電流快速歸零,從而消除該LED像素單元之殘影。
The
然而,隨著輸出通道個數的增加,消影電路的數目也會跟著增加而佔用更多的晶片面積,且會增加更多的靜態功耗。However, as the number of output channels increases, the number of blanking circuits will also increase, occupying more chip area and increasing static power consumption.
為解決上述的問題,本領域亟需一新穎的LED顯示器之消影電路。In order to solve the above problems, there is an urgent need in the art for a novel disappearing circuit for LED displays.
本發明之主要目的在於揭露一種LED顯示器之消影電路,其可藉由使多個電流輸出通道共用一放大器而有效縮減一LED驅動晶片之晶片面積及降低其靜態功耗。The main purpose of the present invention is to disclose a blanking circuit of an LED display, which can effectively reduce the chip area of an LED driver chip and reduce its static power consumption by making multiple current output channels share one amplifier.
本發明之另一目的在於揭露一種LED驅動晶片,其可藉由上述的消影電路有效縮減晶片面積及降低晶片之靜態功耗。Another object of the present invention is to disclose an LED driving chip, which can effectively reduce the chip area and reduce the static power consumption of the chip by the above-mentioned blanking circuit.
本發明之又一目的在於揭露一種顯示裝置,其可藉由上述的消影電路有效縮減其LED驅動晶片之晶片面積及降低其靜態功耗。Another object of the present invention is to disclose a display device, which can effectively reduce the chip area of its LED driver chip and reduce its static power consumption by the above-mentioned blanking circuit.
為達前述目的,一種LED顯示器之消影電路乃被提出,其包括: 一共用放大器,具有一電壓輸出端以輸出一消影電壓;以及 複數個開關,耦接於該電壓輸出端與複數個電流源輸出端之間,係對應地受複數個開關信號之控制,且該些電流源輸出端係用以與一LED陣列耦接; 於操作時,當一被選定的所述電流源輸出端被禁能,一對應之所述開關信號會呈現作用狀態以導通一對應之所述開關以為該被選定的所述電流源輸出端提供該消影電壓,從而為該LED陣列提供一消影功能。 In order to achieve the above-mentioned purpose, a kind of disappearing circuit of LED display is proposed, and it comprises: a shared amplifier having a voltage output terminal to output a vanishing voltage; and A plurality of switches, coupled between the voltage output terminal and a plurality of current source output terminals, are correspondingly controlled by a plurality of switch signals, and the current source output terminals are used for coupling with an LED array; In operation, when a selected output of the current source is disabled, a corresponding switch signal is active to turn on a corresponding switch to provide the selected output of the current source. The erasing voltage provides an erasing function for the LED array.
在可能的實施例中,該LED陣列可為一共陽型LED陣列或一共陰型LED陣列。In a possible embodiment, the LED array can be a common-anode LED array or a common-cathode LED array.
在一實施例中,該些電流源輸出端係複數個電流輸出通道之輸出端,且各該電流輸出通道均具有: 一第一NMOS電晶體,具有一第一閘極、一第一汲極及一第一源極,該第一閘極係用以耦接一第一控制電壓,該第一源極耦接一參考地; 一第二NMOS電晶體,具有一第二閘極、一第二汲極及一第二源極,該第二汲極耦接一所述電流源輸出端,該第二源極耦接該第一汲極;以及 一放大器,具有一負輸入端、一正輸入端及一輸出端,其中,該負輸入端係用以耦接一第二控制電壓,該正輸入端耦接該第二源極,且該輸出端耦接該第二閘極。 In one embodiment, the output terminals of the current sources are the output terminals of a plurality of current output channels, and each of the current output channels has: A first NMOS transistor has a first gate, a first drain and a first source, the first gate is used to couple to a first control voltage, and the first source is coupled to a reference ground; A second NMOS transistor has a second gate, a second drain and a second source, the second drain is coupled to an output terminal of the current source, and the second source is coupled to the first a drain; and An amplifier has a negative input terminal, a positive input terminal and an output terminal, wherein the negative input terminal is used to couple a second control voltage, the positive input terminal is coupled to the second source, and the output The terminal is coupled to the second gate.
在一實施例中,該共用放大器具有一負輸入端、一正輸入端及一輸出端,其中,該負輸入端耦接該輸出端,該正輸入端係用以耦接一第三控制電壓,且且該輸出端耦接該電壓輸出端。In one embodiment, the shared amplifier has a negative input terminal, a positive input terminal and an output terminal, wherein the negative input terminal is coupled to the output terminal, and the positive input terminal is used to couple to a third control voltage , and the output end is coupled to the voltage output end.
為達前述目的,本發明進一步提出一種LED驅動晶片,其具有複數個電流輸出通道及一消影電路,該消影電路包括: 一共用放大器,具有一電壓輸出端以輸出一消影電壓;以及 複數個開關,耦接於該電壓輸出端與該些電流輸出通道之電流輸出端之間,係對應地受複數個開關信號之控制,且該些電流輸出通道之所述電流輸出端係用以與一LED陣列耦接; 於操作時,當一被選定的所述電流輸出通道被禁能,一對應之所述開關信號會呈現作用狀態以導通一對應之所述開關以為該被選定的所述電流輸出通道之所述電流輸出端提供該消影電壓,從而為該LED陣列提供一消影功能。 In order to achieve the aforementioned purpose, the present invention further proposes an LED driver chip, which has a plurality of current output channels and a shadow elimination circuit, and the shadow elimination circuit includes: a shared amplifier having a voltage output terminal to output a vanishing voltage; and A plurality of switches, coupled between the voltage output terminal and the current output terminals of the current output channels, are correspondingly controlled by a plurality of switch signals, and the current output terminals of the current output channels are used for coupled with an LED array; In operation, when a selected current output channel is disabled, a corresponding switch signal will be active to turn on a corresponding switch for the selected current output channel. The current output end provides the disappearing voltage, thereby providing a disappearing function for the LED array.
在可能的實施例中,該LED陣列可為一共陽型LED陣列或一共陰型LED陣列。In a possible embodiment, the LED array can be a common-anode LED array or a common-cathode LED array.
在一實施例中,各該電流輸出通道均具有: 一第一NMOS電晶體,具有一第一閘極、一第一汲極及一第一源極,該第一閘極係用以耦接一第一控制電壓,該第一源極耦接一參考地; 一第二NMOS電晶體,具有一第二閘極、一第二汲極及一第二源極,該第二汲極耦接一所述電流輸出端,該第二源極耦接該第一汲極;以及 一放大器,具有一負輸入端、一正輸入端及一輸出端,其中,該負輸入端係用以耦接一第二控制電壓,該正輸入端耦接該第二源極,且該輸出端耦接該第二閘極。 In one embodiment, each of the current output channels has: A first NMOS transistor has a first gate, a first drain and a first source, the first gate is used to couple to a first control voltage, and the first source is coupled to a reference ground; A second NMOS transistor has a second gate, a second drain and a second source, the second drain is coupled to a current output terminal, and the second source is coupled to the first drain; and An amplifier has a negative input terminal, a positive input terminal and an output terminal, wherein the negative input terminal is used to couple a second control voltage, the positive input terminal is coupled to the second source, and the output The terminal is coupled to the second gate.
在一實施例中,該共用放大器具有一負輸入端、一正輸入端及一輸出端,其中,該負輸入端耦接該輸出端,該正輸入端係用以耦接一第三控制電壓,且該輸出端耦接該電壓輸出端。In one embodiment, the shared amplifier has a negative input terminal, a positive input terminal and an output terminal, wherein the negative input terminal is coupled to the output terminal, and the positive input terminal is used to couple to a third control voltage , and the output end is coupled to the voltage output end.
為達前述目的,本發明進一步提出一種LED顯示裝置,其具有如前述之LED驅動晶片。To achieve the aforementioned purpose, the present invention further provides an LED display device, which has the aforementioned LED driver chip.
在可能的實施例中,該LED陣列可微一次毫米發光二極體陣列、一微發光二極體陣列或一量子點發光二極體陣列。In possible embodiments, the LED array can be a sub-millimeter LED array, a micro LED array or a quantum dot LED array.
為使 貴審查委員能進一步瞭解本發明之結構、特徵及其目的,茲附以圖式及較佳具體實施例之詳細說明如後。In order to enable your review committee members to further understand the structure, features and purpose of the present invention, drawings and detailed descriptions of preferred specific embodiments are hereby attached.
本發明的原理在於:在LED驅動晶片中設置一公共的放大器及多個開關以對各電流輸出通道進行消影操作,藉此免除各輸出通道中的消影放大器,從而得以減小面積、節省成本及降低靜態功耗。The principle of the present invention is: a common amplifier and a plurality of switches are set in the LED driver chip to perform shadow removal operations on each current output channel, thereby eliminating the shadow removal amplifier in each output channel, thereby reducing the area and saving energy. cost and reduce static power consumption.
請參照圖2,其繪示本發明之LED驅動晶片之一實施例的電路圖。如圖2所示,一LED驅動晶片100具有一消影電路110及多個電流輸出通道121,其中,消影電路110具有一共用放大器111及多個開關112。Please refer to FIG. 2 , which shows a circuit diagram of an embodiment of the LED driver chip of the present invention. As shown in FIG. 2 , an
共用放大器111具有一電壓輸出端以輸出一消影電壓,且其係依一控制電壓V
B3產生該消影電壓。詳細而言,共用放大器111具有一負輸入端、一正輸入端及一輸出端,其中,該負輸入端耦接該輸出端,該正輸入端係用以耦接第三控制電壓V
B3,且該輸出端耦接該電壓輸出端。
The
該些開關112係耦接於該電壓輸出端與該些電流輸出通道121之電流輸出端OUT
1~OUT
n之間,且係對應地受複數個開關信號S
1~S
n之控制,且該些電流源輸出端OUT
1~OUT
n係用以與一LED陣列(未示於圖中)耦接,n為大於1之整數。
The
詳細而言,各電流輸出通道121均具有一第一NMOS電晶體121a、一第二NMOS電晶體121b及一放大器121c。In detail, each
第一NMOS電晶體121a具有一第一閘極、一第一汲極及一第一源極,該第一閘極係用以耦接一第一控制電壓V
B1,該第一源極耦接一參考地。
The
第二NMOS電晶體121b具有一第二閘極、一第二汲極及一第二源極,該第二汲極耦接一所述電流源輸出端OUT
j,j為介於1至n之整數,且該第二源極耦接該第一汲極。
The
放大器121c具有一負輸入端、一正輸入端及一輸出端,其中,該負輸入端係用以耦接一第二控制電壓V
B2,該正輸入端耦接該第二源極,且該輸出端耦接該第二閘極。
The
於操作時,當一被選定的電流源輸出端OUT
j被禁能,一對應之開關信號S
j會呈現作用狀態以導通一對應之開關112以為該被選定的電流源輸出端OUT
j提供該消影電壓,從而為該LED陣列提供一消影功能。
In operation, when a selected current source output terminal OUT j is disabled, a corresponding switch signal S j will assume an active state to turn on a
另外,該LED陣列可為一共陽型LED陣列或一共陰型LED陣列。In addition, the LED array can be a common anode LED array or a common cathode LED array.
另外,依上述的說明,本發明進一步提出一種LED顯示裝置。請參照圖3,其繪示本發明之LED顯示裝置之一實施例的方塊圖。如圖3所示,一LED顯示裝置200具有一LED陣列210及用以驅動LED陣列210之一LED驅動晶片220,其中,LED驅動晶片220係由LED驅動晶片100實現。另外,LED陣列210可為一次毫米發光二極體陣列、一微發光二極體陣列或一量子點發光二極體陣列。In addition, according to the above description, the present invention further provides an LED display device. Please refer to FIG. 3 , which shows a block diagram of an embodiment of the LED display device of the present invention. As shown in FIG. 3 , an
藉由前述所揭露的設計,本發明乃具有以下的優點: 一、本發明之LED顯示器之消影電路可藉由使多個電流輸出通道共用一放大器而有效縮減一LED驅動晶片之晶片面積及降低其靜態功耗。 二、本發明之LED驅動晶片可藉由上述的消影電路有效縮減晶片面積及降低晶片之靜態功耗。 三、本發明之顯示裝置可藉由上述的消影電路有效縮減其LED驅動晶片之晶片面積及降低其靜態功耗。 With the design disclosed above, the present invention has the following advantages: 1. The blanking circuit of the LED display of the present invention can effectively reduce the chip area of an LED driver chip and reduce its static power consumption by making multiple current output channels share one amplifier. 2. The LED driver chip of the present invention can effectively reduce the chip area and reduce the static power consumption of the chip by the above-mentioned shadow elimination circuit. 3. The display device of the present invention can effectively reduce the chip area of its LED driver chip and reduce its static power consumption by the above-mentioned disappearing circuit.
本案所揭示者,乃較佳實施例,舉凡局部之變更或修飾而源於本案之技術思想而為熟習該項技藝之人所易於推知者,俱不脫本案之專利權範疇。What is disclosed in this case is a preferred embodiment. For example, any partial changes or modifications derived from the technical ideas of this case and easily deduced by those who are familiar with the technology are within the scope of the patent right of this case.
綜上所陳,本案無論目的、手段與功效,皆顯示其迥異於習知技術,且其首先發明合於實用,確實符合發明之專利要件,懇請 貴審查委員明察,並早日賜予專利俾嘉惠社會,是為至禱。To sum up, regardless of the purpose, means and efficacy of this case, it shows that it is very different from the conventional technology, and its first invention is practical, and it does meet the patent requirements of the invention. I implore your review committee to understand it clearly and grant a patent as soon as possible. Society is for the Most Prayer.
11:電流輸出通道
11a:第一NMOS電晶體
11b:第二NMOS電晶體
11c:第一放大器
11d:第二放大器
100:LED驅動晶片
110:消影電路
111:共用放大器
112:開關
121:電流輸出通道
121a:第一NMOS電晶體
121b:第二NMOS電晶體
121c:放大器
200:LED顯示裝置
210:LED陣列
220:LED驅動晶片11:
圖1繪示一現有LED驅動晶片之一電流輸出通道之電路圖。 圖2繪示本發明之LED驅動晶片之一實施例的電路圖。 圖3繪示本發明之LED顯示裝置之一實施例的方塊圖。 FIG. 1 shows a circuit diagram of a current output channel of a conventional LED driver chip. FIG. 2 shows a circuit diagram of an embodiment of the LED driving chip of the present invention. FIG. 3 shows a block diagram of an embodiment of the LED display device of the present invention.
100:LED驅動晶片 100: LED driver chip
110:消影電路 110: Eradication circuit
111:共用放大器 111: Shared amplifier
112:開關 112: switch
121:電流輸出通道 121: Current output channel
121a:第一NMOS電晶體 121a: the first NMOS transistor
121b:第二NMOS電晶體 121b: the second NMOS transistor
121c:放大器 121c: Amplifier
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CN216980093U (en) * | 2021-11-26 | 2022-07-15 | 西安钛铂锶电子科技有限公司 | Display driving chip and LED lamp panel |
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