【正文】 I 20W 小功率開關(guān)電源的設(shè)計 2020 年 5 月 I 20W 小功率開關(guān)電源的設(shè)計 The Design of 20W Lowpower Switching Power Supply I 摘 要 開關(guān)電源具有功耗小 ， 效率高 ， 穩(wěn)壓范圍廣 ， 體積小等突出優(yōu)點 ， 在通信設(shè)備數(shù)控裝置 ， 儀表儀器影音設(shè)備 ， 家用電器等電子電路中得到廣泛應(yīng)用。 TOP 系列電源為美國 POWER INTEGRATION 公司生產(chǎn)的集成開關(guān)電源 ， 具有集成度高 ， 性價比高 ， 外圍電路簡單 ， 性 能指標(biāo)佳以及能構(gòu)成高效率無工頻變壓器的隔離式開關(guān)電源等優(yōu)點。目前已成為國際上開發(fā)中 、 小功率開關(guān)電源 ， 精密開關(guān)電源及電源模板的優(yōu)選集成電路。 本論文主要有以下內(nèi)容： (1) 介紹開關(guān)電源的發(fā)展史、分類及發(fā)展趨勢，開關(guān)電源常用的幾種控制方法。為研究的論題 — 基于反激式變換器的開關(guān)電源研究作鋪墊。最后講述了本課題的研究意義和工作內(nèi)容。 (2) 介紹反激式開關(guān)電源的工作原理以及 TOP223Y 芯片。 (3) 設(shè)計了基于 TOP223Y 芯片的單端反激式開關(guān)電源。根據(jù) TOP223Y 的特性給出了單端反激式開關(guān)電源的工程設(shè)計方法。對外圍電路的設(shè)計進(jìn)行了分析和討論。 (4) 對給出的具體實例電路進(jìn)行仿真測試研究，得出結(jié)論并加以分析。 關(guān)鍵詞 :開關(guān)電源 TOP223Y 脈寬調(diào)制 單端反激式 II Abstract Switching power supply with low consumption, high efficiency, wide voltage, small advantage in munication equipment, CNC equipment, instrument audio equipment, household appliances, etc widely applied in electronic circuits. TOP . power supply for series of integrated production pany need to switch power, has high integration, costeffective, outer circuit is simple, performance and can form no better efficiency of the isolated transformer switch power supply, etc. At present has bee the international development of small power switch power supply, switching power supply, selection of template and integrated circuits. This paper has the following content: (1) Describes the development history, classification and development trend of switching power supply, switching power supply monly used control methods. For the study of topicbased on the research of switching power supply for flyback converter bedding. Finally describes the significance of the subject and content of work. (2) Introduced the working principle and TOP223Y of Flyback switching power supply chips. (3) Design based on singleend Flyback switching power supply for TOP223Y chip. According to the characteristics of TOP223Y gives singleend Flyback switching power supply design. Analysis and discussion on periphery circuit design. (4) To give specific examples of circuits simulation test study concluded and analysis. Key words: switching power supply TOP223Y pulsewidth modulation singleend flyback III 目 錄 摘要 ................................................................. I Abstract .......................................................................................................................... II 緒論 .................................................................................................................................. 1 1 開關(guān)電源的分類及原理 ......................................................................................... 3 開關(guān)電源的分類 .................................................................................................. 3 單端反激式開關(guān)電源 .................................................................................... 3 單端正激式開關(guān)電源 .................................................................................... 4 自激式開關(guān)穩(wěn)壓電源 .................................................................................... 4 推挽式開關(guān)電源 ............................................................................................. 5 降壓式開關(guān)電源 ............................................................................................. 6 升壓式開關(guān)電源 ............................................................................................. 6 反轉(zhuǎn)式開關(guān)電源 ............................................................................................. 7 開關(guān)電源的基本組成和原理 ............................................................................ 7 PWM 的基本工作方式 及原理 ............................................................................. 8 2 TOP SwitchⅡ 芯片介紹 ....................................................................................... 10 TOP SwitchⅡ系列的特點 ............................................................................ 10 TOP SwitchⅡ結(jié)構(gòu)組成 ................................................................................ 11 TOP SwitchⅡ芯片的工作原理 ................................................................... 13 3 基于 TOP223Y 開關(guān) 電源的設(shè)計 .......................................................................... 15 技術(shù)指標(biāo)和性能要求 ....................................................................................... 15 選擇 TOPSwitch 芯片的型號 .......................................................................... 15 TOP223Y 的主要性能特點和元件選擇 ......................................................... 15 TOP223Y 性能特點 ........................................................................................ 15 線性光耦合器 PC817.................................................................................... 17 可調(diào)式精密并聯(lián)穩(wěn)壓器 TL431 .................................................................. 18 開關(guān)電源的電路設(shè)計 ....................................................................................... 19 IV 基于 TOP223Y 開關(guān)電源原理圖 ................................................................. 19 輸入整流濾波電路 ....................................................................................... 19 高頻變壓器的設(shè)計 ....................................................................................... 20 鉗壓齊納管（ VR）和阻斷二極管（ VD）的選擇 .................................. 22 輸出整流電路的設(shè)計 .................................................................................. 22 反饋電路的設(shè)計 ........................................................................................... 23 開關(guān)電源干擾的產(chǎn)生及其抑制 ..................................................................... 23 開關(guān)電源干擾產(chǎn)生的機(jī)理 ...........................................................