【LED臺(tai)燈電路圖】led充電臺(tai)燈電路圖 LED臺(tai)燈工作(zuo)原(yuan)理

一、簡易LED臺燈電路

先找一臺廢棄的熒光管臺燈，除去燈管及(ji)燈座中的電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)板(ban);準備(bei)兩(liang)塊敷銅板(ban)，一(yi)塊裝(zhuang)串接的88只(zhi)發光(guang)(guang)管，一(yi)塊裝(zhuang)整(zheng)流(liu)(liu)(liu)(liu)濾波(bo)(bo)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)元件(jian)，尺寸依實(shi)際情況而(er)定(ding);采用(yong)(yong)全波(bo)(bo)倍壓(ya)(ya)整(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(整(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)的作用(yong)(yong)是(shi)(shi)將交流(liu)(liu)(liu)(liu)降壓(ya)(ya)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)輸出的電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)較低的交流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)轉換成單(dan)向脈(mo)動性(xing)直流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)，這就(jiu)是(shi)(shi)交流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)的整(zheng)流(liu)(liu)(liu)(liu)過(guo)程，整(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)主(zhu)要(yao)由整(zheng)流(liu)(liu)(liu)(liu)二極管組成。經(jing)過(guo)整(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)之后的電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)已經(jing)不是(shi)(shi)交流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，而(er)是(shi)(shi)一(yi)種(zhong)含(han)有直流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)和交流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)的混合電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)，習慣上(shang)稱(cheng)單(dan)向脈(mo)動性(xing)直流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)。)為發光(guang)(guang)管供電(dian)(dian)(dian)(dian)(dian)(dian)(如(ru)附圖)。兩(liang)只(zhi)0.68uF電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)既是(shi)(shi)全波(bo)(bo)倍壓(ya)(ya)整(zheng)流(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)元件(jian)，又有限(xian)流(liu)(liu)(liu)(liu)作用(yong)(yong)。電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)(rong)選耐(nai)壓(ya)(ya)400V以上(shang)的，電(dian)(dian)(dian)(dian)(dian)(dian)阻用(yong)(yong)0.25W的。由于電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)簡單(dan)，電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)板(ban)用(yong)(yong)刀刻而(er)成，管腳位(wei)置鉆Φlmm焊接孔。

元(yuan)件(jian)(jian)焊好后，先用15kΩ/5W電阻作(zuo)假負(fu)載，測試整流(liu)電路(lu)，電阻上(shang)應(ying)有280V左右的直流(liu)電壓，此時除電阻外，其他元(yuan)件(jian)(jian)不應(ying)發熱(re)。一切(qie)正(zheng)常后接人燈(deng)(deng)(deng)板(ban)(ban)，通電后，88只發光(guang)管應(ying)正(zheng)常發光(guang)。最后，將電源(yuan)板(ban)(ban)和燈(deng)(deng)(deng)板(ban)(ban)分(fen)別固定在底座和燈(deng)(deng)(deng)罩上(shang)。該臺燈(deng)(deng)(deng)亮度(du)不及(ji)原燈(deng)(deng)(deng)，且照亮面(mian)積偏(pian)小，但看(kan)書寫字尚可，點亮一段時間后燈(deng)(deng)(deng)板(ban)(ban)溫度(du)升高，但比熒光(guang)燈(deng)(deng)(deng)管溫度(du)低(di)得多。測量負(fu)載回路(lu)電流(liu)約(yue)18mA，燈(deng)(deng)(deng)板(ban)(ban)兩端電壓約(yue)280V，計(ji)算其功耗約(yue)5W。

制(zhi)作時要(yao)(yao)注(zhu)(zhu)意，焊接不得有虛焊，LED要(yao)(yao)逐只(zhi)測試且極性不得焊錯(cuo);電(dian)源進線要(yao)(yao)加裝電(dian)流小于(yu)200mA的(de)保險管;斷電(dian)后電(dian)容元件有高壓要(yao)(yao)注(zhu)(zhu)意安全;電(dian)路不可斷開負載，否則600V左右的(de)電(dian)壓可能損壞元件。

二、LED臺燈工作原理

遵循安全第一(yi)的(de)(de)(de)民用(yong)(yong)(yong)電(dian)器(qi)的(de)(de)(de)設計理念，LED 光(guang)(guang)(guang)源是一(yi)種(zhong)低(di)電(dian)壓(ya)直(zhi)流(liu)恒流(liu)源的(de)(de)(de)發光(guang)(guang)(guang)器(qi)件，不能用(yong)(yong)(yong)100-220V 的(de)(de)(de)交(jiao)(jiao)流(liu)高(gao)壓(ya)電(dian)直(zhi)接點(dian)亮，因此，LED 臺燈(deng)方(fang)(fang)案(an)設計思路(lu)，首先要將(jiang)高(gao)壓(ya)的(de)(de)(de)交(jiao)(jiao)流(liu)電(dian)變換(huan)成(cheng)低(di)壓(ya)的(de)(de)(de)直(zhi)流(liu)恒流(liu)源，才(cai)能點(dian)亮LED 光(guang)(guang)(guang)源。使用(yong)(yong)(yong)最經(jing)(jing)濟(ji)有效的(de)(de)(de)方(fang)(fang)法(fa)降(jiang)壓(ya)和進行(xing)交(jiao)(jiao)直(zhi)流(liu)變換(huan)是設計的(de)(de)(de)首要考慮，今便攜式電(dian)產(chan)品使用(yong)(yong)(yong)交(jiao)(jiao)流(liu)電(dian)源的(de)(de)(de)交(jiao)(jiao)直(zhi)流(liu)降(jiang)壓(ya)變換(huan)器(qi)--適配器(qi)（Adapter）就成(cheng)了既經(jing)(jing)濟(ji)實惠(hui)、又現成(cheng)、好用(yong)(yong)(yong)的(de)(de)(de)首選。適配器(qi)的(de)(de)(de)輸出電(dian)壓(ya)要求穩定在(zai)DC12V，輸出電(dian)流(liu)要根據LED 的(de)(de)(de)光(guang)(guang)(guang)源的(de)(de)(de)功率來選擇，一(yi)般要給(gei)予(yu)30%的(de)(de)(de)余量，以3X1W 的(de)(de)(de)白(bai)光(guang)(guang)(guang)LED 光(guang)(guang)(guang)源為(wei)例，1W 的(de)(de)(de)白(bai)光(guang)(guang)(guang)LED 的(de)(de)(de)標(biao)準(zhun)工(gong)作電(dian)流(liu)應為(wei)350mA，因而3 個LED 光(guang)(guang)(guang)源串聯其電(dian)路(lu)需(xu)要的(de)(de)(de)電(dian)流(liu)也是350mA，考慮到延長LED 壽命和降(jiang)低(di)光(guang)(guang)(guang)衰(shuai)，可以設計為(wei)300mA--330mA，不會(hui)明顯的(de)(de)(de)影響(xiang)LED 發光(guang)(guang)(guang)的(de)(de)(de)亮度，所以適配器(qi)的(de)(de)(de)輸出電(dian)流(liu)應選750mA--1A 的(de)(de)(de)。

LED 臺燈(deng)一種簡(jian)潔實用的(de)(de)(de)(de)(de)方案如(ru)圖1 所(suo)示。AC220V 經(jing)由適(shi)配器在燈(deng)具外的(de)(de)(de)(de)(de)安全降壓(ya)變(bian)換(huan)，向LED 臺燈(deng)提供(gong)穩定(ding)的(de)(de)(de)(de)(de)12V 直(zhi)(zhi)流電源(yuan)，在臺燈(deng)底座(zuo)殼內安置恒(heng)流源(yuan)電源(yuan)板，將直(zhi)(zhi)流電壓(ya)變(bian)換(huan)成穩定(ding)的(de)(de)(de)(de)(de)直(zhi)(zhi)流恒(heng)流源(yuan)，以滿足(zu)LED 光源(yuan)發光的(de)(de)(de)(de)(de)技術要求。在直(zhi)(zhi)流恒(heng)流源(yuan)前可(ke)加一電源(yuan)開(kai)關(guan)(guan)，以便(bian)在臺燈(deng)不(bu)用時可(ke)關(guan)(guan)斷直(zhi)(zhi)流電源(yuan)，但不(bu)能關(guan)(guan)斷220V 交流電源(yuan)，因此真的(de)(de)(de)(de)(de)不(bu)用時應從墻上取下適(shi)配器的(de)(de)(de)(de)(de)電源(yuan)插頭，這(zhe)也是這(zhe)個(ge)實用方案的(de)(de)(de)(de)(de)唯一“缺點”。如(ru)不(bu)想采用機(ji)械(xie)開(kai)關(guan)(guan)，和想要一個(ge)更有創意的(de)(de)(de)(de)(de)賣(mai)點，可(ke)選用電子(zi)觸摸開(kai)關(guan)(guan)，如(ru)手指(zhi)輕點可(ke)實現臺燈(deng)的(de)(de)(de)(de)(de)開(kai)->全亮、半暗、關(guan)(guan)；由于電子(zi)技術的(de)(de)(de)(de)(de)快速(su)進步，電子(zi)觸摸開(kai)關(guan)(guan)如(ru)今已是一個(ge)低(di)成本(ben)的(de)(de)(de)(de)(de)器件(jian)。