【LED臺(tai)燈(deng)電(dian)(dian)路圖(tu)】led充(chong)電(dian)(dian)臺(tai)燈(deng)電(dian)(dian)路圖(tu) LED臺(tai)燈(deng)工作原理

一、簡易LED臺燈電路

先找一臺廢棄的熒光管臺燈，除去(qu)燈(deng)管(guan)及燈(deng)座中的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)板(ban);準(zhun)備(bei)兩塊敷銅板(ban)，一(yi)塊裝串接(jie)的(de)(de)88只發光管(guan)，一(yi)塊裝整(zheng)(zheng)流(liu)(liu)(liu)(liu)(liu)(liu)濾(lv)波電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)元件，尺寸依(yi)實(shi)際情況而定;采用(yong)全(quan)波倍壓(ya)整(zheng)(zheng)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)(整(zheng)(zheng)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)的(de)(de)作(zuo)(zuo)用(yong)是(shi)(shi)將交(jiao)流(liu)(liu)(liu)(liu)(liu)(liu)降壓(ya)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)輸出的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)較低的(de)(de)交(jiao)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)轉(zhuan)換成(cheng)單向(xiang)脈動(dong)性(xing)直流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)，這就(jiu)是(shi)(shi)交(jiao)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)整(zheng)(zheng)流(liu)(liu)(liu)(liu)(liu)(liu)過(guo)程，整(zheng)(zheng)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)主要由整(zheng)(zheng)流(liu)(liu)(liu)(liu)(liu)(liu)二極管(guan)組成(cheng)。經過(guo)整(zheng)(zheng)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)之后的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)已經不是(shi)(shi)交(jiao)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)，而是(shi)(shi)一(yi)種含(han)有(you)(you)直流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)和交(jiao)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)的(de)(de)混合電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)，習慣上稱(cheng)單向(xiang)脈動(dong)性(xing)直流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)。)為發光管(guan)供電(dian)(dian)(dian)(dian)(dian)(dian)(如附圖)。兩只0.68uF電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)既是(shi)(shi)全(quan)波倍壓(ya)整(zheng)(zheng)流(liu)(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)元件，又有(you)(you)限(xian)流(liu)(liu)(liu)(liu)(liu)(liu)作(zuo)(zuo)用(yong)。電(dian)(dian)(dian)(dian)(dian)(dian)容(rong)選(xuan)耐壓(ya)400V以上的(de)(de)，電(dian)(dian)(dian)(dian)(dian)(dian)阻用(yong)0.25W的(de)(de)。由于電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)簡單，電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)(lu)(lu)板(ban)用(yong)刀刻(ke)而成(cheng)，管(guan)腳位置鉆Φlmm焊接(jie)孔。

元件焊好后(hou)，先(xian)用15kΩ/5W電(dian)(dian)(dian)阻(zu)作假負載(zai)，測(ce)試(shi)整(zheng)流電(dian)(dian)(dian)路，電(dian)(dian)(dian)阻(zu)上(shang)應(ying)(ying)有(you)280V左右的直流電(dian)(dian)(dian)壓，此時除電(dian)(dian)(dian)阻(zu)外，其他元件不應(ying)(ying)發熱(re)。一切正常后(hou)接人燈(deng)(deng)(deng)板，通電(dian)(dian)(dian)后(hou)，88只發光(guang)管(guan)應(ying)(ying)正常發光(guang)。最(zui)后(hou)，將(jiang)電(dian)(dian)(dian)源板和燈(deng)(deng)(deng)板分別固定在底座和燈(deng)(deng)(deng)罩上(shang)。該臺燈(deng)(deng)(deng)亮(liang)度不及(ji)原燈(deng)(deng)(deng)，且(qie)照亮(liang)面積偏小，但看書寫字尚可，點亮(liang)一段時間后(hou)燈(deng)(deng)(deng)板溫度升高，但比(bi)熒光(guang)燈(deng)(deng)(deng)管(guan)溫度低得多。測(ce)量(liang)負載(zai)回路電(dian)(dian)(dian)流約(yue)18mA，燈(deng)(deng)(deng)板兩(liang)端電(dian)(dian)(dian)壓約(yue)280V，計算(suan)其功耗約(yue)5W。

制作時要(yao)注(zhu)意(yi)(yi)，焊(han)接不得有虛焊(han)，LED要(yao)逐只測試且極性(xing)不得焊(han)錯;電(dian)(dian)源進(jin)線要(yao)加裝電(dian)(dian)流小(xiao)于200mA的保險管;斷電(dian)(dian)后電(dian)(dian)容元(yuan)件有高壓要(yao)注(zhu)意(yi)(yi)安全;電(dian)(dian)路不可斷開負載(zai)，否則600V左右的電(dian)(dian)壓可能損壞(huai)元(yuan)件。

二、LED臺燈工作原理

遵(zun)循安(an)全(quan)第一的(de)(de)(de)(de)民(min)用(yong)(yong)電(dian)(dian)(dian)器的(de)(de)(de)(de)設(she)(she)計理念，LED 光(guang)(guang)(guang)源(yuan)(yuan)是一種(zhong)低電(dian)(dian)(dian)壓(ya)直(zhi)(zhi)流(liu)(liu)(liu)恒流(liu)(liu)(liu)源(yuan)(yuan)的(de)(de)(de)(de)發(fa)光(guang)(guang)(guang)器件，不(bu)(bu)能(neng)用(yong)(yong)100-220V 的(de)(de)(de)(de)交(jiao)流(liu)(liu)(liu)高壓(ya)電(dian)(dian)(dian)直(zhi)(zhi)接點亮，因此(ci)，LED 臺燈方案設(she)(she)計思路，首先要(yao)將高壓(ya)的(de)(de)(de)(de)交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)變換成低壓(ya)的(de)(de)(de)(de)直(zhi)(zhi)流(liu)(liu)(liu)恒流(liu)(liu)(liu)源(yuan)(yuan)，才能(neng)點亮LED 光(guang)(guang)(guang)源(yuan)(yuan)。使(shi)用(yong)(yong)最經濟有效的(de)(de)(de)(de)方法降(jiang)壓(ya)和(he)進(jin)行交(jiao)直(zhi)(zhi)流(liu)(liu)(liu)變換是設(she)(she)計的(de)(de)(de)(de)首要(yao)考慮，今便(bian)攜式電(dian)(dian)(dian)產品使(shi)用(yong)(yong)交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)源(yuan)(yuan)的(de)(de)(de)(de)交(jiao)直(zhi)(zhi)流(liu)(liu)(liu)降(jiang)壓(ya)變換器--適配(pei)器（Adapter）就成了既經濟實惠、又(you)現(xian)成、好用(yong)(yong)的(de)(de)(de)(de)首選(xuan)(xuan)。適配(pei)器的(de)(de)(de)(de)輸出電(dian)(dian)(dian)壓(ya)要(yao)求穩(wen)定在DC12V，輸出電(dian)(dian)(dian)流(liu)(liu)(liu)要(yao)根據LED 的(de)(de)(de)(de)光(guang)(guang)(guang)源(yuan)(yuan)的(de)(de)(de)(de)功率來(lai)選(xuan)(xuan)擇，一般要(yao)給予30%的(de)(de)(de)(de)余量，以(yi)3X1W 的(de)(de)(de)(de)白光(guang)(guang)(guang)LED 光(guang)(guang)(guang)源(yuan)(yuan)為(wei)例，1W 的(de)(de)(de)(de)白光(guang)(guang)(guang)LED 的(de)(de)(de)(de)標(biao)準工作(zuo)電(dian)(dian)(dian)流(liu)(liu)(liu)應(ying)為(wei)350mA，因而3 個LED 光(guang)(guang)(guang)源(yuan)(yuan)串聯其電(dian)(dian)(dian)路需要(yao)的(de)(de)(de)(de)電(dian)(dian)(dian)流(liu)(liu)(liu)也(ye)是350mA，考慮到延長LED 壽命(ming)和(he)降(jiang)低光(guang)(guang)(guang)衰，可以(yi)設(she)(she)計為(wei)300mA--330mA，不(bu)(bu)會明顯的(de)(de)(de)(de)影響LED 發(fa)光(guang)(guang)(guang)的(de)(de)(de)(de)亮度(du)，所以(yi)適配(pei)器的(de)(de)(de)(de)輸出電(dian)(dian)(dian)流(liu)(liu)(liu)應(ying)選(xuan)(xuan)750mA--1A 的(de)(de)(de)(de)。

LED 臺燈(deng)(deng)一種簡潔實用(yong)的(de)方案如(ru)圖1 所示(shi)。AC220V 經由適配器(qi)(qi)在燈(deng)(deng)具外(wai)的(de)安全(quan)降(jiang)壓變換，向LED 臺燈(deng)(deng)提供穩定的(de)12V 直(zhi)流(liu)(liu)電(dian)源，在臺燈(deng)(deng)底座殼內(nei)安置恒(heng)流(liu)(liu)源電(dian)源板，將直(zhi)流(liu)(liu)電(dian)壓變換成(cheng)穩定的(de)直(zhi)流(liu)(liu)恒(heng)流(liu)(liu)源，以滿足LED 光源發光的(de)技術要求。在直(zhi)流(liu)(liu)恒(heng)流(liu)(liu)源前可(ke)加一電(dian)源開(kai)關(guan)(guan)，以便在臺燈(deng)(deng)不(bu)用(yong)時(shi)可(ke)關(guan)(guan)斷直(zhi)流(liu)(liu)電(dian)源，但不(bu)能關(guan)(guan)斷220V 交流(liu)(liu)電(dian)源，因此真的(de)不(bu)用(yong)時(shi)應從墻上取下適配器(qi)(qi)的(de)電(dian)源插頭，這(zhe)(zhe)也是這(zhe)(zhe)個(ge)實用(yong)方案的(de)唯一“缺點”。如(ru)不(bu)想(xiang)采用(yong)機械(xie)開(kai)關(guan)(guan)，和(he)想(xiang)要一個(ge)更有創意的(de)賣(mai)點，可(ke)選用(yong)電(dian)子觸(chu)摸(mo)(mo)開(kai)關(guan)(guan)，如(ru)手指輕點可(ke)實現臺燈(deng)(deng)的(de)開(kai)->全(quan)亮、半暗(an)、關(guan)(guan)；由于電(dian)子技術的(de)快(kuai)速進步，電(dian)子觸(chu)摸(mo)(mo)開(kai)關(guan)(guan)如(ru)今已是一個(ge)低成(cheng)本(ben)的(de)器(qi)(qi)件。