led灯设计.doc

LED灯设计


摘要：LED灯是近年来快速兴起的一种新颖光源, 它的很多良好特点使得它的应用面越来越广。LED 的单向导电特性使许多人认为理应用直流驱动, 但是对直流稳压和限流的装置在保证比较好的限流特性时, 自身功耗是很大的, 所以使系统的效率大为降低。只有用较高频率的交流来驱动LED,并且用在呈现较大阻抗时自身功耗较小的电感或电容来限流, 才能把LED 驱动电路的限流特性和自身功耗都做得比较理想。
本文所设计的智能调光LED 台灯系统，它采用的是单片机为控制核心，运用恒流驱动方案与PWM调光技术实现LED台灯的多级调光控制。适合于现代家庭的实际需要。可以预见，随着LED 照明技术的不断发展完善，节能高效的LED将在家用照明领域发挥着日益重要的作用。
关键词：驱动电路；LED；智能调光

Abstract: in recent years, the rapid rise of the LED lamp is a novel light source, its many good characteristics make it more extensive application. LED one-way electrical properties that many people think that the physical application of DC drive, but on the DC voltage and current limiting device to ensure better current limiting characteristics, its power consumption is large, so the efficiency of the system is greatly reduced. Only with high frequency AC to drive LED, and used in a larger impedance when its power consumption smaller inductance or capacitance current limiting, can the LED driver circuit for current limiting characteristics and their own power to do quite ideal.
In this paper, the intelligent dimming LED lamp system using AT89S51MCU as the control core, the use of constant current driving scheme and PWM dimming technology to realize the L ED lamp multistage dimming control. Suitable for the actual demands of modern families. Can foreknow, with the LED lighting technology and continuously improve the development, energy saving and high efficiency in the field of household lighting LED will play an increasingly important role in.
Key words:  driving circuit; LED; intelligent dimming
 

目 录

中文摘要及关键词 I
英文摘要及关键词 II
正文 1
第一章 绪论 1
一、研究背景 1
二、研究意义 1
第二章  LED特性、驱动要求及调光方式 2
一、LED的优势 2
二、LED的特性 3
三、LED的驱动要求 4
第三章 电源转换模块 7
一、电源转换模块介绍 7
二、电源转换模块工作原理 8
三、主要参数设计 10
四、无源PFC 11
第四章 LED的PWM驱动电路设计 12
一、PWM信号的原理和形成 12
二、PWM驱动白光LED 13
第五章 智能调光模块 15
一、系统主程序 15
二、按键检测和处理程序 16
三、闹钟中断程序 17
四、电路设计部分 19
参考文献 21