高效精密可调开关电源.doc

毕 业 论 文 ?? 摘要 开关电源利用现代，控制开关管开通和关断的时间比率，维持稳定输出电压 High Precision Adjustable Switching Power Supply Abstract Switching power supply is?the use of modern electronic technology, it controls?the time ratio of switch?turn-on and turn off. The output voltage can be?maintained?stable. Switching power supply?must consistent with three?characteristics of the switching,?high frequency and direct. So this study has began research from the three aspects in order to achieve lower power, reduce power consumption and energy saving effect. The traditional switching power supply have some features with a heavy power?consumption, severe fever,the conversion efficiency is also low, generally only reach 60% -70%. The research is in the design of a D/A sample, D/A feedback, the radio transceiver system, the stable driving load of the LCD display and other issues. It is improved on the basis of traditional switching power supply, the study applied switching?voltage regulator amd buck?power management?IC. The maximum output current value is 3A in the realization of?load?in certain circumstances. The?heavy?difficult?point of the design is the accuracy of it , the accuracy of ordinary switching power supply is 100mA, but the accuracy of this study is 20mA. In addition, the design has realized the all indicators. In this paper, it takes?the switching power supply?system?as the core to expand. and it describes high-precision adjustable switching power supply to achieve constant current stable output process, it focus on single-chip control switching power supply module to export stable and accurate output current value. Keywords: switching power supply precision adjustable efficient low power consumption 目录 第一章 引言 1 1.1 课题背景与来源 1 1.2 课题设计的意义 2 1.3 课题设计功能和方案 2 第二章 系统概述 4 2.1 系统组成 4 2.2 系统的功能介绍及操作说明 5 第三章 硬件组成与设计 7 3.1 整体电路图 7 3.2 从机供电电源 7 3.3 单片机AT89S52 8 3.4 12864液晶显示屏 9 3.5 NRF24L01无线模块 12 3.6 MAX531 15 3.8 LM2596和SG3524 18 第四章 程序流程图与软件设计 25 4.1程序流程图 25 4.2软件设计介绍 26 第五章