冷光源照明系统的大学论文.doc

毕业论文 冷光源照明系统的研究 摘 要 随着能源危机的加剧，绿色高效的照明系统得到了人们的广泛重视。我国在1996年也推出了“中国绿色照明工程，旨在我国发展和推广高效照明器具，逐步替代传统的低效照明电光源，节约照明用电。冷光源LED以其高效率、低功耗、低电压驱动、使用寿命长以及节能环保等优点，引起了全世界的广泛关注，被越来越多的应用于各种照明场合，在可预见的将来将有可能进入一般照明市场以替代传统的热照明方案成为新一代照明光源。因此，研究针对冷光源LED驱动电路的研究设计有很重要的意义。 本文基于高性能、低功耗的8位AVR微处理器研究冷光源照明技术。 采用单通道输出的LED恒流驱动器驱动高达1安培的沈入电流（sink current），并可透过调整参考输入电流()来任意设定输出电流的大小。微调或使能偏压电压可校正LED间的亮度不一或实现多颗LED间整体亮度同时调整。采用LNK306来替代输出电流小于360mA的所有线性及电容降压式非隔离电源。其系统成本与所替代的电源相等，但性能更好、效率更高。采用AD590温度检测，适用于150℃以下、目前采用传统电气温度传感器的任何温度检测应用。低成本的单芯片集成电路及无需支持电路的特点，使它成为许多温度测量应用的一种很有吸引力的备选方案。应用AD590时，无需线性化电路、精密电压放大器、电阻测量电路和冷结补偿。 关键词：LED 恒流驱动 Abstract As the aggravation of energy crisis，green and efficient light system gets more and more attention．In 1 996，China launched“China Green Lighting Project’，which was in order to develop and promote high-efficient lighting apparatuses，gradually substitute the traditional low-efficient lighting apparatuses，and save lighting electricity．Power white LED has aroused world wide interest because of its high efficiency，low power loss，low drive voltage，long service life，energy-conversation and other advantages，to be applied in many kinds of illuminance situation．In the foreseeable future，power white LED may enter the common lighting market to displace the traditional illuminance methods and become the new generation lighting source．So，it has the very vital significance to research the driving circuit of power white LED． Based on high-performance, low-power 8-bit AVR microcontrollers study cold-light illumination technology. Single-output LED Driver drive up to 1 Amp sink current (sink current), and can be arbitrarily set the size of the output current by adjusting the reference input current (IREF). Fine-tuning, or to enable the bias voltage can be corrected brightness varies between the LED or the overall brightness of the LED at the same time to adjust. The adopted LNK306 to replace the output current is less than 360mA of all linear and capacitor-isolated power supply. Th