摘要自 1968 年美国首先实验性的研制出了 LCD 产品,电视史便翻开了一个崭新 的篇章。随后,夏普公司在 1973 年研制出 TN-LCD,从此 LCD 电视走上了一条 飞速发展的快车道。在接下来的几十年内,从 STN-LCD 再到 TFT-LCD,LCD 电视的工业制造水平不断的提高,尤其是新千年后,TFL-LCD 在性能上已经与 传统的 CRT 有了一较高下的能力,特别在最近的几年里,LCD 电视早就取代了 CRT 电视成为消费者更加青睐的电视产品。由于 LCD 电视市场需求的逐步扩大, 消费者对 LCD 的性能,外观设计,屏幕大小,颜色,功耗等级有了更高的要求, 如何研制出美观轻薄,功能强大,性价比相对较高的新产品是摆在诸多电视厂商 的难题。目前来说,一般的 LCD 电视的电源部分和 LCD 背光驱动部分相对独立, 分步实现对 LCD 电视的控制,大尺寸 LCD 电视中通常会采用两到三级电能转换, 相对应的会带来电能利用率的减低、部分电子元器件反复使用丶复杂的电路构造 等一系列问题。72733
本文简要介绍了 LCD 电视的研究背景和国内外研究现状,根据 LCD 电源的 基本理论,以“节能”“简洁”为设计主旨,在对大尺寸液晶电视电源设计要求 的基础上,对几种不同方案的比较后,确定了以 PFC 电路和反激电路为电源主 构架,LLC 谐振拓扑为 LED 背光驱动主电路的总体系统结构。本设计全面深入的 讨论了临界连续模式下的 PFC 主电路的设计,同时给出基于 NCP33262 芯片下 的 PFC 控制电路设计。详细分析了反激电路的构造,给出了基于 FAN6755 芯片 的反激电路设计构造。对 LLC 谐振变换器在一定开关范围进行分析其工作原理 和过程,同时给出了 LLC 谐振变换器设计构造,其对应的芯片 LX27901 也设计 了控制电路。
该论文有图 22 幅,表 2 个,参考文献 25 篇。
毕业论文关键词:液晶电视电源 反激拓扑 整流滤波 功率因数校正 谐振变换器
LCD TV Driver Power Supply Design
ABSTRACT Since 1968, the first experimental developed LCD products, television has opened a new chapter。 Then, sharp corp。 in 1973 developed the TN LCD, LCD TV has come a rapid development since then the fast lane。 In the next few decades, from the STN LCD to TFT - LCD, LCD TV manufacturing level continuously improve, especially the new one thousand years later, the TFL - LCD in performance with the traditional CRT has already one's ability to compete, particularly in recent years, LCD TV is gradually replace CRT TV as consumers preferred products。Due to the LCD TV market demand gradually expanding, the consumer on the performance of the LCD, appearance design, screen size, color, power consumption level have higher requirements, how to develop beautiful thin, powerful, relatively high performance-to-price ratio new product is facing the problem of many TV makers。For now, the general LCD TV is relatively independent power supply and LCD backlight driving part, step by step to realize control of the LCD TV, large size LCD TV commonly used two to three electrical energy conversion, the corresponding will bring the utilization ratio of energy reducing, part of the repeated use of electronic components, complex circuit structure and a series of problems。
This paper briefly introduces the research background and research status at home and abroad of LCD TV, according to the basic theory of LCD power supply, in order to "energy saving" "concise" as the design theme, the large size LCD TV power supply design requirements, on the basis of comparing several different schemes, determines the PFC circuit and flyback circuit for power supply main frame, LLC resonant topology for the LED backlight driving the overall system structure of main circuit。 This design is discussed in-depth critical continuous mode PFC main circuit design, at the same time is given based on NCP33262 chip under the PFC control circuit design。 Flyback circuit structure is analyzed in detail, gives the flyback circuit design structure based on FAN6755 chip。 Analyze the LLC resonant converter in a certain range switch its working principle and process, design structure and LLC resonant converter is presented, the corresponding chip LX27901 also design the control circuit。