【LED臺燈(deng)(deng)電路圖】led充電臺燈(deng)(deng)電路圖 LED臺燈(deng)(deng)工(gong)作(zuo)原理

一、簡易LED臺燈電路

先找一臺廢棄的熒光管臺燈，除去燈管及燈座中的電(dian)(dian)(dian)(dian)路板;準備兩塊(kuai)(kuai)敷銅板，一(yi)(yi)塊(kuai)(kuai)裝(zhuang)(zhuang)串接的88只發(fa)光管，一(yi)(yi)塊(kuai)(kuai)裝(zhuang)(zhuang)整(zheng)(zheng)(zheng)流(liu)(liu)(liu)濾波(bo)電(dian)(dian)(dian)(dian)路元件，尺寸依實際情況而定;采用(yong)全波(bo)倍壓(ya)(ya)整(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)路(整(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)路的作(zuo)用(yong)是將交(jiao)流(liu)(liu)(liu)降壓(ya)(ya)電(dian)(dian)(dian)(dian)路輸出的電(dian)(dian)(dian)(dian)壓(ya)(ya)較低的交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)轉(zhuan)換(huan)成單(dan)向脈動性直(zhi)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)，這就是交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)的整(zheng)(zheng)(zheng)流(liu)(liu)(liu)過程，整(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)路主要由(you)整(zheng)(zheng)(zheng)流(liu)(liu)(liu)二極管組(zu)成。經過整(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)路之后(hou)的電(dian)(dian)(dian)(dian)壓(ya)(ya)已(yi)經不(bu)是交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)，而是一(yi)(yi)種含有(you)直(zhi)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)和交(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)的混合電(dian)(dian)(dian)(dian)壓(ya)(ya)，習慣上(shang)稱單(dan)向脈動性直(zhi)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)。)為(wei)發(fa)光管供電(dian)(dian)(dian)(dian)(如附(fu)圖)。兩只0.68uF電(dian)(dian)(dian)(dian)容(rong)既是全波(bo)倍壓(ya)(ya)整(zheng)(zheng)(zheng)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)路元件，又有(you)限流(liu)(liu)(liu)作(zuo)用(yong)。電(dian)(dian)(dian)(dian)容(rong)選耐壓(ya)(ya)400V以上(shang)的，電(dian)(dian)(dian)(dian)阻用(yong)0.25W的。由(you)于電(dian)(dian)(dian)(dian)路簡單(dan)，電(dian)(dian)(dian)(dian)路板用(yong)刀刻而成，管腳位置鉆Φlmm焊接孔。

元(yuan)件焊(han)好(hao)后(hou)(hou)，先用15kΩ/5W電(dian)阻作假負(fu)載，測試整流電(dian)路，電(dian)阻上應有280V左右的直流電(dian)壓，此(ci)時除電(dian)阻外(wai)，其他元(yuan)件不應發熱。一切正常后(hou)(hou)接人燈板(ban)，通(tong)電(dian)后(hou)(hou)，88只發光管應正常發光。最后(hou)(hou)，將電(dian)源(yuan)板(ban)和燈板(ban)分(fen)別固(gu)定在底座(zuo)和燈罩(zhao)上。該臺(tai)燈亮(liang)度不及(ji)原燈，且照亮(liang)面積偏(pian)小，但看書寫字尚可，點亮(liang)一段(duan)時間(jian)后(hou)(hou)燈板(ban)溫(wen)度升高(gao)，但比熒(ying)光燈管溫(wen)度低得多。測量負(fu)載回路電(dian)流約(yue)18mA，燈板(ban)兩端電(dian)壓約(yue)280V，計算其功耗約(yue)5W。

制作時要注意，焊(han)接不得(de)有虛(xu)焊(han)，LED要逐(zhu)只(zhi)測試且(qie)極(ji)性(xing)不得(de)焊(han)錯;電(dian)(dian)源進線要加裝電(dian)(dian)流小于200mA的保(bao)險(xian)管;斷電(dian)(dian)后電(dian)(dian)容元件(jian)有高壓要注意安全;電(dian)(dian)路不可(ke)斷開(kai)負載，否(fou)則600V左右(you)的電(dian)(dian)壓可(ke)能(neng)損壞元件(jian)。

二、LED臺燈工作原理

遵循安全第一(yi)的(de)(de)(de)(de)(de)民用電(dian)(dian)(dian)器(qi)(qi)的(de)(de)(de)(de)(de)設(she)計理念(nian)，LED 光(guang)(guang)(guang)源(yuan)(yuan)是一(yi)種低(di)電(dian)(dian)(dian)壓(ya)直(zhi)流(liu)(liu)恒(heng)流(liu)(liu)源(yuan)(yuan)的(de)(de)(de)(de)(de)發光(guang)(guang)(guang)器(qi)(qi)件，不(bu)能用100-220V 的(de)(de)(de)(de)(de)交(jiao)流(liu)(liu)高壓(ya)電(dian)(dian)(dian)直(zhi)接點亮，因此，LED 臺燈(deng)方(fang)案設(she)計思路(lu)，首先(xian)要(yao)將高壓(ya)的(de)(de)(de)(de)(de)交(jiao)流(liu)(liu)電(dian)(dian)(dian)變換(huan)(huan)成低(di)壓(ya)的(de)(de)(de)(de)(de)直(zhi)流(liu)(liu)恒(heng)流(liu)(liu)源(yuan)(yuan)，才能點亮LED 光(guang)(guang)(guang)源(yuan)(yuan)。使用最經(jing)濟(ji)有(you)效的(de)(de)(de)(de)(de)方(fang)法降壓(ya)和(he)進(jin)行交(jiao)直(zhi)流(liu)(liu)變換(huan)(huan)是設(she)計的(de)(de)(de)(de)(de)首要(yao)考慮(lv)，今便(bian)攜式電(dian)(dian)(dian)產品使用交(jiao)流(liu)(liu)電(dian)(dian)(dian)源(yuan)(yuan)的(de)(de)(de)(de)(de)交(jiao)直(zhi)流(liu)(liu)降壓(ya)變換(huan)(huan)器(qi)(qi)--適配(pei)器(qi)(qi)（Adapter）就成了既經(jing)濟(ji)實惠、又(you)現(xian)成、好用的(de)(de)(de)(de)(de)首選。適配(pei)器(qi)(qi)的(de)(de)(de)(de)(de)輸出(chu)電(dian)(dian)(dian)壓(ya)要(yao)求(qiu)穩定在DC12V，輸出(chu)電(dian)(dian)(dian)流(liu)(liu)要(yao)根據LED 的(de)(de)(de)(de)(de)光(guang)(guang)(guang)源(yuan)(yuan)的(de)(de)(de)(de)(de)功率來(lai)選擇，一(yi)般要(yao)給予(yu)30%的(de)(de)(de)(de)(de)余量，以3X1W 的(de)(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)(de)白光(guang)(guang)(guang)LED 的(de)(de)(de)(de)(de)標(biao)準工作電(dian)(dian)(dian)流(liu)(liu)應為(wei)350mA，因而3 個LED 光(guang)(guang)(guang)源(yuan)(yuan)串聯其電(dian)(dian)(dian)路(lu)需要(yao)的(de)(de)(de)(de)(de)電(dian)(dian)(dian)流(liu)(liu)也是350mA，考慮(lv)到延長(chang)LED 壽命和(he)降低(di)光(guang)(guang)(guang)衰，可(ke)以設(she)計為(wei)300mA--330mA，不(bu)會明顯(xian)的(de)(de)(de)(de)(de)影響LED 發光(guang)(guang)(guang)的(de)(de)(de)(de)(de)亮度，所以適配(pei)器(qi)(qi)的(de)(de)(de)(de)(de)輸出(chu)電(dian)(dian)(dian)流(liu)(liu)應選750mA--1A 的(de)(de)(de)(de)(de)。

LED 臺(tai)(tai)燈(deng)一(yi)種簡潔實用(yong)的(de)方(fang)(fang)案如圖1 所示。AC220V 經(jing)由適配器(qi)(qi)在(zai)(zai)燈(deng)具外的(de)安全(quan)降(jiang)壓變換，向(xiang)LED 臺(tai)(tai)燈(deng)提供穩定(ding)的(de)12V 直(zhi)流(liu)(liu)電(dian)(dian)源(yuan)，在(zai)(zai)臺(tai)(tai)燈(deng)底座殼(ke)內安置恒(heng)(heng)(heng)流(liu)(liu)源(yuan)電(dian)(dian)源(yuan)板，將直(zhi)流(liu)(liu)電(dian)(dian)壓變換成穩定(ding)的(de)直(zhi)流(liu)(liu)恒(heng)(heng)(heng)流(liu)(liu)源(yuan)，以滿足LED 光源(yuan)發(fa)光的(de)技(ji)術(shu)(shu)要求。在(zai)(zai)直(zhi)流(liu)(liu)恒(heng)(heng)(heng)流(liu)(liu)源(yuan)前可加一(yi)電(dian)(dian)源(yuan)開(kai)(kai)關(guan)，以便在(zai)(zai)臺(tai)(tai)燈(deng)不(bu)用(yong)時可關(guan)斷直(zhi)流(liu)(liu)電(dian)(dian)源(yuan)，但(dan)不(bu)能關(guan)斷220V 交流(liu)(liu)電(dian)(dian)源(yuan)，因(yin)此真的(de)不(bu)用(yong)時應從墻上(shang)取下適配器(qi)(qi)的(de)電(dian)(dian)源(yuan)插頭，這也是這個(ge)實用(yong)方(fang)(fang)案的(de)唯一(yi)“缺點(dian)”。如不(bu)想采(cai)用(yong)機械開(kai)(kai)關(guan)，和想要一(yi)個(ge)更(geng)有創(chuang)意(yi)的(de)賣點(dian)，可選用(yong)電(dian)(dian)子觸摸開(kai)(kai)關(guan)，如手指輕點(dian)可實現臺(tai)(tai)燈(deng)的(de)開(kai)(kai)->全(quan)亮、半暗、關(guan)；由于電(dian)(dian)子技(ji)術(shu)(shu)的(de)快速(su)進(jin)步，電(dian)(dian)子觸摸開(kai)(kai)關(guan)如今已是一(yi)個(ge)低成本的(de)器(qi)(qi)件。