【开关电源】论文.doc

毕业设计（论文） 题 目：基于单片机的开关电源设计 指导教师： 董宏丽 职称： 学生姓名： 宋欣浩 学号： 110601141228 专 业： 自动化 院（系）： 电气信息工程 完成时间： 2015年 6 月 日 摘 要 本文介绍了一种基于单片机控制的数控开关电源—直流稳压电源，采用了STC89C51RC，配合D/A转换器件DAC0808和LM317三端稳压块实现电压连续可调。同时能通过LED数码管显示相应的电压值，直观、可靠、实用！该系统由初步整流稳压部分、单片机控制部分、DAC、稳压部分和显示部分组成。该稳压电源可步进调节、实时显示，弥补了传统稳压电源的不足，其核心技术是通过单片机控制数模转换来改变其后稳压模块的输出。利用单片机控制数模转换芯片DAC0808输出电压作为稳压电路的参考电压；稳压电路采用的是串联型稳压电路，单片机控制的DAC0808的输出电压具有高稳定性，参考电压稳定进而能够很好地保证输出端电压的稳定性；单片机通过键控改变DAC0808的输出电压，作为参考电压发生改变，稳压电路调整管的压降也会相应地发生变化，从而改变输出电压；另外，电路还设计了数码管显示电路，以增加稳压电源使用的直观性，配合键控电路使电源使用起来非常方便直观。 关键词：单片机；稳压电源；连续步进可调；DAC Abstract This text introduces one kind of digital control switching mode power supply, This article describes a DC voltage-stabilized power supply design scheme based on single-chip, preliminary rectifier voltage parts, the system by single-chip computer control part, DAC, voltage regulators and display components. The regulator can be adjusted stepped, real-time display, make up for the lack of traditional power supply, the core technology is controlled by single-chip digital-analog conversion to change the output of the voltage regulator module. Using single tablets machine control number die conversion chip DAC0808 output voltage as regulator circuit of reference voltage; regulator circuit used of is series type regulator circuit, single tablets machine control of DAC0808 of output voltage has high stability, reference voltage stability turn to is good to guarantee output end voltage of stability; single tablets machine by key control change DAC0808 of output voltage, as reference voltage occurs change, regulator circuit adjustment tube of pressure drop also will corresponding to occurs changes, to change output voltage; and circuit design of digital display circuits, to increase the voltage stabilizing power of intuitive, with the keyed circuit power is very easy and intuitive to use. Key word: MCU； Regulated Power Supply； Stepping and adjustable row； DAC 目