摘要在各式各样的电子实验中，电源作为最基本的需要器件之一，应用很多。因此，设计出一种高精度的可调输出的电源是很有必要的，这不但能满足不同电子实验的要求，而且能满足在同一实验中使用不同的电压值来测试的要求。本篇论文设计了一种高精度的程控稳压电源。该电源的功能主要由两部分实现，即硬件与软件。硬件方面，包括变压器、整流电路、滤波电路、稳压电路、反馈电路、保护电路、程控电路、显示电路以及支持单片机运行的复位电路和时钟电路。220V的市电电压通过变压器被输入系统，经过整流电路和滤波电路后变成近似直流的电压，再经过稳压电路部分稳压，获得稳定的直流输出。稳压电路使用达林顿管作为调整管，由运放电路作为反馈取样之后的放大电路，并利用其来提高调整管的反应灵敏度以及电压稳定性。软件方面，使用单片机进行语言编程，用以控制程控部分，程控部分由三个部分组成，即：单片机，D/A、A/D部分。该部分的作用是，控制稳压电路部分基准电压的输出与调整，同时实现高精度的输出，并且控制数码管显示的输出电压。整个电路的设计，是在综合考虑各个模块现有的电路的基础上，选择最佳电路来实现设计目标。 80390

毕业论文关键词  直流稳压电源；整流；滤波；程控；D/A；A/D

毕业设计说明书外文摘要

Title Programmable DC power supply             

Abstract In various electronic experiments, as the most basic needs,power devices have a lot of applications。 Therefore, it is necessary to design a high-precision adjustable output power, not only to meet the requirements of different electronic experiments, but also to meet the need that using different voltage values in the same experiment to test voltage values。This paper presents a high-precision programmable power supply。 The main function of the realization of power supply is composed of two parts: hardware and software。 Hardware includes a transformer, rectifier, filter circuit, voltage regulator circuit, feedback circuit, protection circuits, programmable circuit, display circuit ,the reset and clock circuitry which is to support the running of MCU 。 220V mains voltage flows into the system through a transformer, after rectification and filtration ,it becomes approximately DC voltage stable DC output voltage and then it will be regulated by voltage regulator circuit 。 Voltage regulator circuit uses Darlington regulator as a regulator,the op amp circuit is used as a feedback amplifier circuit after sampling, and it is used to improve the response sensitivity and voltage stability of adjustment tube。 The part of software uses micro-controller to program language , which is for controlling programmable control parts, namely: SCM, D / A, A / D section。 This part plays the role of controlling the adjustment and the output of reference voltage in regulation circuit, while achieving high accuracy output, and controls the output voltage of the digital display。The entire circuit is designed in consideration of the existing integrated circuit modules, based on selecting the best circuit to achieve design goals。

Keywords  DC power supply; rectification; filter; control; D/A; A/D

目   次

1 绪论1

1。1 课题背景及意义 1

1。2 国内外发展现状1

1。3 系统的研究方向2

2 总体方案论证3 

2。1 系统方案3 

2。2 稳压电源基本原理3 

3 主要元件的介绍5 

3。1 AT89C51简介5

3。2 DAC0832简介6

3。3 数码管显示原理8

3。4 矩阵式键盘10

3。5 LM317简介11

4 硬件电路设计13