外文翻译--26万色VGA TFT液晶单芯片低功耗驱动集成电路.docx

附录ALow Power 260k Color VGA TFT LCD One-chipDriver ICAbstract - In this study, we present a 260k Color VGA TFT one-chip LCD Driver IC that consumes low power in module.To reduce power consumption and a chip size, we used a sub-pixel rendering and a data compression algorithm.The currently, in order to display the bigger and higher resolution, the imbedded graphic SRAM size becomes bigger.But, because the mass-production size has limitation, the driver IC of a VGA resolution is normally two or three chip solution.The study is the first time made VGA one-chip IC in world. The IC is implemented in a 0.15um process.I. INTRODUCTIONCurrent telecommunication technology has improved amazingly.These improvements have revitalized hand-held modules and increased multi-media services.To use a hand- held module for a longer time, each chip needs to become smaller and consume less power.The size of display equipment has become bigger and the resolution higher. Due to this, power consumption of display equipment has also become higher. Power reduction for display equipment has become a very important issue.The multi-color display panel is implemented by arranging an RGB (red, green, blue) color filter.The color rectangular panel is supplied by row-direct voltage and column-direct voltage. The difference of the two direct voltages is the driving voltage of the pixels. This method is called multiplex addressing. The LCD driver IC generates and supplies the voltage level.This paper presents a 260 k-color TFT LCD one-chip driver module that consists of a gate driver and source driver. The gate driver generates the driving voltage of column direction and common voltage. The gate driving voltage is of two types: a selected level and a non-selected level. The level of these voltages is determined by the characteristics of each panel. When one gate line is selected, the source IC drives data voltage levels that are valued by decoding stored data. The different voltage of the gates selected level and sources data level determine the display material arrangement.With a higher color resolution, the embedded memory capacity needs to be bigger in the LCD driver IC. The power consumption of the merged memory also becomes a very important issue. With a higher resolution and bigger panel，a bigger embedded memory size is necessary. Because of this, shrinking the RAM size is a dominant factor in the chip size of a driver IC.In this paper, section II presents the architecture of graphic driving IC. Section III discusses the algorithm of sub-pixel rendering. Section IV discusses the image data compression. Section V, the implemented sample is compared in VGA driver IC. The chip samples are implemented in a 0.15 um process and tested in manual test board and probing machine (T6371 Advantest).II. STRUCTURE OF THE DRIVER ICGenerally, the driver IC is composed of a logic part, an analog part, and a memory part. The analog part is composed of the LCD driver, DCDC converter, voltage divider, and oscillator. The oscillator circuit generates a clock for display. The DCDC converter circuit receives the generated clock and generates the highest/lowest voltage level. The voltage divider circuit divides between the highest and lowest level. The driver block supplies the various voltages to the panel.The 260k TFT one-chip IC is composed of a logic, a embedded memory, an oscillator, a DCDC converter block, a source/gate driver block and a common voltage generating block. The logic part is composed of an MPU interface block, memory-addressing block, and timing control block. The MPU interface block interfaces between the driver IC and the external MPU.The memory-addressing block receives the decoded signal in the MPU interface and generates the memory address.The resister array is included in the gray scale generator.The implemented driving IC has three types of adjustment: a gradient adjustment, an amplitude adjustment, and a fine adjustment. The timing control block generates a signal, which controls the display panel.The embedded memory is the same as normal memory. The output data from memory is transferred to the source driver. The driver has the sub-pixel rendering and compressing process in order to decrease the embedded memory size. A data form external chip is received by the system interface block, the internal format converted data of a processed in system interface is sent to GMA block (Input gamma block), the pre-SPR formatted data is sent to SPR (Sub-Pixel Rendering) block. The SPR block calculates the one pixel with around pixel data and then output processed a sub-pixel data. Because the sub-pixel data has the around pixel information, the stored data can be lower data quantity.The sub-pixel is sent to compressing block and the compressed output is stored in the embedded memory.The stored data is decompressed and output to the source driver in the display clock. The display data in the source driver block is not same with normal RGB strips type. The data type is called the Pentile Matrix type. The Pentile Matrix type can be had original visibility in a human eye.The sub-pixel rendering and the compression processing can be had lower memory size and low power consumption than the normal processing.III. SUB-PIXEL RENDERINGThe sub-pixel rendering algorithm in out chip is used a Clair Voyantes algorithm 3, 4. The present application relates to the conversion of graphics data formats from one form to another, and specifically to the conversion of (red-green-blue) RGB graphics to improved color pixel arrangements used in displays.The present state of the art of color single plane imaging matrix, for flat panel displays, use the RGB color triad or a single color in a vertical stripe as shown in prior art Figure. 1. The system takes advantage of the Von Bezold color blending effect by separating the three colors and placing equal spatial frequency weight on each color. However, these panels are a poor match to human vision.Graphic rendering techniques have been developed to improve the image quality of prior art panels.Benzchawel,etal.in3 teaches how to reduce an image of a larger size down to a smaller panel. In so doing, Benzchawel, et al. teach how to improve the image quality using a technique now known in the art as sub-pixel rendering. More recently Hill, etal. in 4 teach how to improve text quality by reducing a virtual image of text, one character at a time, using the very same sub-pixel rendering technique.The above prior art pay inadequate attention to how human vision operates. The prior arts reconstruction of the image by the display device is poorly matched to human vision. The dominant model used in sampling, or generating,and then storing the image for these displays is the RGB pixel ( or three-color pixel element), in which the red, green,and blue values are on an orthogonal equal spatial resolution grid and are co-incident. One of the consequences of using this image format is that it is a poor match both to the real image reconstruction panel,with its spaced apart, non-coincident, color emitters, and the human vision.This effectively results in redundant, or wasted, information in the image.Full color perception is produced in the eye by three-color receptor nerve cell types called cones. The three types are sensitive to different wave lengths of light: long, medium, and short (red, green, and blue, respectively). The relative density of the three wavelengths differs significantly form one another. There are slightly more red receptors than green receptors. There are very few blue receptors compared to red or green receptors. In addition to the color receptors, there are relative wavelength insensitive receptors called rods that contribute to monochrome night vision.The human vision system processes the information detected by the eye in several perceptual channels: luminance, chrominance, and motion. Motion is only important for flicker threshold to the imaging system designer. The luminance channel takes the input from only the red and green receptors. It is color blind. It processes the information in such a manner that the contrast of edges is enhanced. The chrominance channel does not have edge contrast enhancement. Since the luminance channel uses and enhances every red and green receptor, the resolution of the luminance channel is several times higher than the chrominance channel. The blue receptor contribution to luminance perception is negligible. Thus, the error introduced by lowering the blue resolution by one octave will be barely noticeable by the most perceptive viewer, if at all, as experiments at Xerox and NASA, Ames Research Center (R Martin, J. Gille, J. Larimer, Detectability of Reduced Blue Pixel Count in Projection Displays,SID Digest 1993)had demonstrated.Color perception is influenced by a process called assimilation or the Von Bezold color blending effect. This is what allows separate color pixels (or sub-pixels or emitters) of a display to be perceived as the mixed color. This blending effect happens over a given angular distance in the field of view.Because of the relatively scarce blue receptors,the blending happens over a greater angle for blue than for red or green.This distance is approximately 0.25 degree subtends 50 miles(1,270u)on a display.Thus,if the blue sub-pixel pitch is less than half (625u) of this blending pitch,the colors will blend without loss of picture quality.Sub-pixel rendering, in its most simplistic implementation, operates by using the sub-pixels as approximately equal brightness pixels perceived by the luminance channel. This allows the sub-pixels to serve as sampled image reconstruction points as opposed to using the combined sub-pixels as part of a ture pixel.By using sub-pixel rendering,the spatial sampling is increased,reducing the phase error.If the color of the image were to be ignored, then each sub-pixel may serve as a though it were a monochrome pixel,each equal. However, as color is nearly always important (and why else would one use a color display?). then color balance of a given image is important at each location.Thus,the sub-pixel rendering algorithm must maintain color balance by ensuring that high spatial frequency information in the luminance component of the image to be rendered does not alias with the color sub-pixels to introduce color errors. The approaches taken by Benzchawel, et al. in 3, and Hill, et al. In 4, are similar to a common anti-aliasing technique that applies displaced decimation filters to each separate color component of a higher resolution virtual image. This ensures that the luminance information does not alias within each color channel. Figure 1. RGBW strip detection in eyes附录B26万色VGA TFT液晶单芯片低功耗驱动集成电路摘要-在这项研究中，我们提出了一个26万色VGA TFT液晶单芯片低功率消耗驱动集成电路。为了降低能耗和芯片尺寸，我们使用了子像素渲染和数据压缩算法。目前，为了显示更大的和更高的分辨率，要求嵌入式图形静态随机存储器尺寸变得更大。但是，由于大规模生产规模的限制，要实现该驱动集成电路的VGA分辨率通常是两个或三个芯片才能解决。这项研究是在世界第一次实现的VGA单芯片集成电路。该集成电路是在0.15um工艺下实现的。一. 导言目前的通信技术在以惊人的速度提高，这些改进促使了手持设备的产生并增加了多媒体服务。为了使手持设备工作更长的时间，每个芯片需要变得更小和能耗更低。显示设备的尺寸已经越来越大并具有更高的分辨率。由于这些，使得显示设备的能耗也变得更高。对显示设备的降耗已经成为一个非常重要的问题 多彩色显示面板是通过设置一个RGB （红，绿，蓝）彩色滤光片来实现的。彩色矩形面板是通过行和列直接电压来供电的。差异的两个直接电压是像素的驱动电压。这种方法被称为多路处理。LCD驱动集成电路产生并提供电压标准。 本文提出了一个由门驱动器和源驱动器组成的26万真彩色液晶单芯片驱动装置。门驱动器产生列方向的驱动电压和一个共同的电压。门驱动电压分为两类：选择一级和非选择一级。这些水平的电压是由每个面板的特点来决定的。当一个门线被选中，源集成电路驱动被解码存储的数据电压一级。门的选择级别和源的数据级别不同的电压确定于材料的实现。要有较高的色彩解析度，在LCD驱动器集成电路中的嵌入式存储容量就需要更大。集成内存的耗电量也成为一个非常重要的问题。由于较高的分辨率和更大的面板，具有一个更大嵌入式内存是必要的。正因为如此，缩小随机储存期的容量是决定驱动集成电路芯片大小的主要因素。本文第二部分介绍了图形驱动集成电路的架构。第三节讨论了子像素渲染的算法。第四节讨论了图像数据压缩。第五节中，在VGA驱动集成电路执行样品的比较。该芯片样品执行0.15微米这个工艺并在手工测试板和探测机（爱德T6371）上经过了测试 。二. 驱动集成电路的结构一般来说，驱动集成电路由一个逻辑部分，模拟部分，内存部分组成。模拟部分由LCD驱动器，数码制作转换器，分压器和振荡器组成。振荡电路产生一个显示时钟。数码制作转换电路接收时钟并产生最高/最低电压标准。分压器在最高和最低电平间驱动。驱动模块为面板提供不同的电压。26万色TFT单芯片集成电路有一个逻辑部分，嵌入式存储器，一个振荡器，一个数码制作转换块，源/栅极驱动块和一个共同的电压生成块组成。逻辑部分由一个微控制器接口模块，内存处理块，和定时控制模块组成。该微控制器接口块连接驱动器集成电路和外部微控制器。内存处理块接收微控制器接口的解码信号，并生成内存地址。电阻阵列包含于灰阶生成器。执行驱动集成电路有三种类型的调整：梯度调整，幅度调整，以及微调。时间控制模块生成一个控制显示面板的信号。嵌入式内存跟正常的内存一样。从内存输出的数据被转移到源驱动器。为了便降低嵌入式存储器的容量，该驱动器有子像素渲染和压缩过程。外部芯片传来的数据被系统接口模块接收，处理系统接口的内部格式转换数据被发送到图形处理器模块（输入伽玛块），预子像素格式的数据发送到子像素渲染模块。子像素渲染模块计算出一个像素与周围像素数据，然后输出处理了的子像素数据。由于子像素数据包含有周围像素的信息，可以降低存储数据的数据量。子像素被发送到压缩块，而压缩的输出则是被储存到嵌入式存储器中。 在显示时钟下，存储的数据被解压并且输出到源驱动器。在原驱动器模块中的显示数据跟平常的RGB带类型不一样，其数据类型被称为Pentile矩阵式。Pentile矩阵含有人眼能见的原始能见度。子像素渲染和压缩处理可以比正常的处理减少内存容量的消耗和降低耗电量。三. 子像素渲染外部芯片中的子像素渲染算法是采用了克莱尔Clair Voyante的算法 3 和 4 。当前的应用涉及到转换的图形数据格式从一个到另一个形式，特别是从（红绿蓝） RGB图形到用于显示的改善彩色像素阵列的转换。用于平板显示器的色彩单一平面成像矩阵技术的现状，就是使用RGB色彩三合会或在垂直条纹的单一颜色如图1所示。该系统通过分离三种颜色和为每种颜色设置相同的空间频率比重，充分利用了Von Bezold的颜色混合效应。但是，这些面板对人眼来说就很无味了。图形渲染技术在朝着改善预先艺术面板的图像质量方向发展。Benzchawe