【正文】 ............. III 插入圖表 ...................................................................................................................................... V 引 言 ..................................................................................................................................... VI 第 1 章 緒論 .............................................................................................................................. 1 課題背景與意義 ................................................................................................................. 1 課題研究歷程與現(xiàn)狀 ......................................................................................................... 1 本課題的研究?jī)?nèi)容與目標(biāo) .................................................................................................. 2 第 2 章 開關(guān)電源的基 本工作原理與電路結(jié)構(gòu) ........................................................................... 3 開關(guān)電源概述 .................................................................................................................... 3 開關(guān)電源的工作原理 ................................................................................................... 3 開關(guān)電源的組成 .......................................................................................................... 5 開關(guān)電源的特點(diǎn) .......................................................................................................... 5 DCDC 變換電路拓?fù)涓攀? ................................................................................................. 7 單端反激式電壓變換器 ............................................................................................... 7 推挽式電壓變換器 ...................................................................................................... 7 單端正激式電壓變換器 ............................................................................................... 8 半橋變換器 ................................................................................................................. 9 全橋變換器 ................................................................................................................. 9 第 3 章 高頻變壓器設(shè)計(jì) .......................................................................................................... 11 “黑箱”預(yù)先估計(jì) .......................................................................................................... 11 設(shè)計(jì)反激式變壓器 ........................................................................................................ 11 第 4 章 控制單元的選擇 .......................................................................................................... 14 UC3842 的簡(jiǎn)介 ................................................................................................................. 14 UC3842 的封裝形式 ................................................................................................... 14 UC3842 內(nèi)部電路框圖介紹 ........................................................................................ 14 UC3842 的工作原理 ................................................................................................... 15 xx 基于 UC3842 的開關(guān)穩(wěn)壓電源的設(shè)計(jì) IV UC3842 功能介紹 ....................................................................................................... 16 外圍電路設(shè)計(jì) ....................................................................................................... 17 工作頻率設(shè)計(jì) ............................................................................................................. 17 第 5 章 開關(guān)電源設(shè)計(jì) .............................................................................................................. 18 開關(guān)器件的選擇 ............................................................................................................... 18 開關(guān)器件的特征 ........................................................................................................ 18 器件 TL431 ............................................................................................................... 18 電力二極管 ............................................................................................................... 19 光耦 PC817 ............................................................................................................... 20 啟動(dòng)電路和 PWM 脈沖控制驅(qū)動(dòng)電路 .............................................................................. 22 啟動(dòng)電路設(shè)計(jì) ............................................................................................................. 22 PWM 脈沖控制驅(qū)動(dòng)電路設(shè)計(jì) .................................................................................... 22 輸入濾波電路 .................................................................................................................. 23 輸出濾波電路的設(shè)計(jì) ....................................................................................................... 23 輸出濾波電容的設(shè)計(jì) .................................................................................................. 23 死區(qū)電阻的設(shè)計(jì) ......................................................................................................... 24 過流保護(hù) 電路 .................................................................................................................. 25 電壓反饋電路 .................................................................................................................. 25 開關(guān)電源總電路圖及工作過程分析 .................................................................................. 27 工作過程與原理分析 .................................................................................................. 27 結(jié)論與展望 ................................................................................................................................ 29 致謝 ........................................................................................................................................... 30 參考文獻(xiàn) .................................................................................................................................... 31