【正文】 power supply to provide the various chips, digital amplifier control and the required operating voltage, display circuit for displaying the size of power supply output voltage, output voltage value may be stepping through the control button (177。與傳統(tǒng)的穩(wěn)壓電源相比具有操作方便，電源穩(wěn)定性高以及其輸出電壓大小采用數(shù)碼顯示的特點(diǎn)。輔助電源提供各個(gè)芯片、數(shù)碼管和放大器所需工作電壓，顯示電路用于顯示電源輸出電壓的大小，輸出電壓值可通過按鍵對其進(jìn)行步進(jìn)控制（177。摘 要本文主要論述了一種基于 AT89C51 單片機(jī)為核心控制器的數(shù)控直流穩(wěn)壓電源的設(shè)計(jì)原理和實(shí)現(xiàn)方法，其主要由輔助電源、顯示電路、控制電路、數(shù)模轉(zhuǎn)換電路、穩(wěn)壓電路等部分組成。該系統(tǒng)原理是以 AT89C51 單片機(jī)為控制單元， ，以數(shù)模轉(zhuǎn)換芯片 DAC0809 進(jìn)行轉(zhuǎn)換為模擬信號。） ，并且在按鍵長時(shí)間按下的時(shí)候能連續(xù)增加或減小。該系統(tǒng)具有抗干擾性能好，可靠性高，及最終輸出電壓值與真實(shí)顯示值精確度較高等優(yōu)點(diǎn)。 ), and a long button press when under the continuous increase or decrease. And pared to the traditional regulated power supply with easy to operate, high power stability, as well as the size of the output voltage characteristics of the use of digital display. This system has the resistance to interference well, the reliability is high, and finally output voltage value and real demonstration value precision higher merit.Key words: Digital DC Voltagestabilized Power Source AT89C51 DAC0809 目 錄摘 要 .............................................................................................................................................................................IDESIGN OF DIGITAL POWER SOURCE .............................................................................................................IIABSTRACT .................................................................................................................................................................II第一章 緒論 ..................................................................................................................................................................3第二章 電源概述及方案設(shè)計(jì) ......................................................................................................................................5 直流穩(wěn)壓源概述及定義 .....................................................................................................................................5 方案的比較與選擇 .............................................................................................................................................5 傳統(tǒng)直流穩(wěn)壓源 .......................................................................................................................................5 數(shù)控直流穩(wěn)壓電源 ...................................................................................................................................6 方案的最終選擇 .......................................................................................................................................7 數(shù)控直流穩(wěn)壓電源設(shè)計(jì)方案及結(jié)構(gòu) .....................................................................................................................7 系統(tǒng)總體設(shè)計(jì)方案 .........................................................................................................................................8 數(shù)控直流穩(wěn)壓源總體結(jié)構(gòu) .............................................................................................................................8第三章 硬件系統(tǒng)設(shè)計(jì) ..................................................................................................................................................9 控制模塊的分析 .................................................................................................................................................9 單片機(jī)簡介 ................................................................................................................................................9 AT89C51 單片機(jī)簡介 ..............................................................................................................................11 AT89C51 單片機(jī)的性能參數(shù)： ..............................................................................................................11 AT89C51 內(nèi)存空間 ...............................................................................................................................12 AT89C51 單片機(jī)的功能特性概述 ........................................................................................................12 AT89C51 接口設(shè)計(jì) ..................................................................................................................................15 顯示模塊 ...........................................................................................................................................................16 數(shù)碼顯示輸出部分 ..................................................................................................................................16 鍵盤模塊 ..........................................................................................................................................................17 ..................................................................................................................................17 芯片方案選擇 ..............................................................................................................................................17 DAC0809 的簡介 ...........................................................................................................................................17:LM317 介紹 ...................................................................................................................................................20第四章 輔助電源設(shè)計(jì) ................................................................................................................................................22 輔助電源模塊 ...................................................................................................................................................22 串聯(lián)線性穩(wěn)壓模塊 ...........................................................................................................................................23 集成運(yùn)放作比較電路 .......................................................................................................................................234．5 串聯(lián)線性穩(wěn)壓電路的應(yīng)用 ........