【手機(ji)充(chong)電器】手機(ji)充(chong)電器電路圖講解 手機(ji)充(chong)電器輸(shu)出電流多(duo)少合(he)適
手機充電器電路圖
手機充電器電路圖講解
分析一個電源，往往從輸入開始著手。220V交流輸入，一(yi)端經過一(yi)個4007半波整流，另一端經過一個10歐的電阻后，由10uF電(dian)容濾(lv)波。這(zhe)個10歐(ou)的電阻(zu)用來做保護的，如果后面出現故(gu)(gu)障等(deng)導致過(guo)流，那么這個電阻(zu)將(jiang)被(bei)燒斷，從而避免引起更大的故(gu)(gu)障。右邊的4007、4700pF電容、82KΩ電(dian)阻，構(gou)成一個(ge)高壓吸收電(dian)路，當(dang)開(kai)關管13003關(guan)斷時，負責吸收線圈上的感應(ying)電(dian)壓(ya)，從而防止(zhi)高壓(ya)加(jia)到開關(guan)管13003上(shang)而(er)導致擊穿。13003為開關管（完(wan)整的名(ming)應該是MJE13003），耐壓400V，集(ji)電(dian)極最大電(dian)流1.5A，最大集電(dian)極功耗為(wei)14W，用來控(kong)制原邊(bian)繞(rao)組(zu)與電源之間的(de)通(tong)、斷。當原邊(bian)繞(rao)組(zu)不停的(de)通(tong)斷時，就會在開關(guan)變壓器中形成變化的(de)磁場，從而在次級繞(rao)組(zu)中產生感應電壓。由于圖中沒有標明繞(rao)組(zu)的(de)同名端，所以不能看出是(shi)正激(ji)式(shi)還是(shi)反激(ji)式(shi)。
不過，從這個電路的結構來看，可以推測出來，這個電源應該是反激式的。左端的510KΩ為啟動(dong)電(dian)阻，給(gei)開關管提供(gong)啟動(dong)用的基(ji)極電(dian)流。13003下(xia)方的10Ω電阻(zu)為電流取樣電阻(zu)，電流經取樣后變成電壓（其(qi)值為10*I），這電壓經二極管4148后，加至(zhi)三極管C945的(de)基(ji)極(ji)上。當取樣(yang)電壓大(da)約(yue)大(da)于1.4V，即開關(guan)管電流大于0.14A時，三極管C945導(dao)通(tong)，從而將開關(guan)管13003的基極(ji)電(dian)(dian)壓拉低，從而集電(dian)(dian)極(ji)電(dian)(dian)流(liu)減小(xiao)，這(zhe)樣就限(xian)制(zhi)了(le)開(kai)關的電(dian)(dian)流(liu)，防止(zhi)電(dian)(dian)流(liu)過大而燒毀（其(qi)實這(zhe)是一個恒流(liu)結構(gou)，將開(kai)關管的最(zui)大電(dian)(dian)流(liu)限(xian)制(zhi)在140mA左(zuo)右）。
變壓器左下方的繞組（取樣繞組）的感應電壓經整流二極管4148整流，22uF電容濾波后(hou)形(xing)成取樣電壓(ya)。為了分析方(fang)便(bian)，我們(men)取三極管C945發射極(ji)一端為(wei)地。那么這取樣電壓就是負的（-4V左右），并且(qie)輸出(chu)電(dian)壓(ya)越高時，采樣(yang)(yang)電(dian)壓(ya)越負。取樣(yang)(yang)電(dian)壓(ya)經過(guo)6.2V穩壓二極管后，加至開關管13003的基極。前面說了，當輸出電壓越高時，那么取樣電壓就越負，當負到一(yi)定程(cheng)度后，6.2V穩壓二極(ji)管(guan)被擊穿(chuan)，從而將(jiang)開關13003的(de)(de)基極電(dian)(dian)位拉低(di)，這將導(dao)(dao)致開關管斷開或者推(tui)遲開關的(de)(de)導(dao)(dao)通，從而控制了能(neng)量輸入到變壓器中，也就控制了輸出電(dian)(dian)壓的(de)(de)升高，實現了穩壓輸出的(de)(de)功能(neng)。
而下方的1KΩ電(dian)阻(zu)跟串聯的(de)2700pF電容，則(ze)是(shi)正反饋支路，從取樣繞(rao)組(zu)中(zhong)取出(chu)感應電壓，加到(dao)開(kai)關管的(de)基極(ji)上，以維持振(zhen)蕩。右邊的(de)次級繞(rao)組(zu)就沒有太多好說的(de)了，經二極(ji)管RF93整流，220uF電(dian)容(rong)濾波后輸出(chu)6V的電壓。沒找到二(er)極管RF93的(de)(de)資料，估(gu)計是一個(ge)快速回復管，例如肖特基(ji)二極管等(deng)，因為(wei)開關電(dian)源的(de)(de)工作(zuo)頻(pin)率較高，所以(yi)需要工作(zuo)頻(pin)率的(de)(de)二極管。這里可以(yi)用常見的(de)(de)1N5816、1N5817等肖特(te)基二(er)極管代替(ti)。
同樣(yang)因(yin)為(wei)頻率高的(de)原(yuan)因(yin)，變壓器也必須(xu)使用高頻開關變壓器，鐵心一般為(wei)高頻鐵氧體(ti)磁芯，具(ju)有高的(de)電阻率，以減小渦(wo)流。
手機充電器輸出電流多少合適
手機電(dian)(dian)(dian)池容(rong)量(liang)基本是定型的，電(dian)(dian)(dian)池的充(chong)電(dian)(dian)(dian)時間跟充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流大(da)小息(xi)(xi)息(xi)(xi)相關，在同等充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流下，電(dian)(dian)(dian)池容(rong)量(liang)越(yue)(yue)(yue)大(da)所需的充(chong)電(dian)(dian)(dian)時間越(yue)(yue)(yue)長，同理，充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流越(yue)(yue)(yue)大(da)，所需的充(chong)電(dian)(dian)(dian)時間越(yue)(yue)(yue)短。
如(ru)果充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)所能(neng)提供的(de)(de)電(dian)(dian)(dian)(dian)流(liu)小(xiao)(xiao)(xiao)于(yu)原裝充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)標準電(dian)(dian)(dian)(dian)流(liu)，充(chong)(chong)電(dian)(dian)(dian)(dian)時(shi)間勢必(bi)要延長，如(ru)1830毫安的(de)(de)容量(liang)(liang)，原裝的(de)(de)充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)是1.2安的(de)(de)，那么就(jiu)需要4小(xiao)(xiao)(xiao)時(shi)左右才能(neng)將一塊(kuai)完全沒(mei)電(dian)(dian)(dian)(dian)的(de)(de)電(dian)(dian)(dian)(dian)池充(chong)(chong)滿，而再小(xiao)(xiao)(xiao)一點電(dian)(dian)(dian)(dian)流(liu)的(de)(de)充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)使用(yong)的(de)(de)充(chong)(chong)電(dian)(dian)(dian)(dian)時(shi)間會(hui)更長，如(ru)果電(dian)(dian)(dian)(dian)流(liu)過小(xiao)(xiao)(xiao)還(huan)會(hui)充(chong)(chong)不(bu)(bu)上(shang)(shang)電(dian)(dian)(dian)(dian)，大(da)(da)家可(ke)能(neng)沒(mei)有注意到在(zai)原裝的(de)(de)小(xiao)(xiao)(xiao)6電(dian)(dian)(dian)(dian)池上(shang)(shang)容量(liang)(liang)后(hou)(hou)面還(huan)有個7.0wh，1830毫mah/7.0wh，后(hou)(hou)面的(de)(de)7.0wh指的(de)(de)是瓦時(shi)，mah（毫安時(shi)）和(he)wh（瓦時(shi)）是比較常見的(de)(de)2種表示電(dian)(dian)(dian)(dian)池容量(liang)(liang)的(de)(de)方式，用(yong)mah乘以電(dian)(dian)(dian)(dian)池額定電(dian)(dian)(dian)(dian)壓就(jiu)等于(yu)wh，以小(xiao)(xiao)(xiao)6的(de)(de)電(dian)(dian)(dian)(dian)池為(wei)(wei)例就(jiu)是1.83*3.7=12.81瓦時(shi)（指的(de)(de)是每小(xiao)(xiao)(xiao)時(shi)消(xiao)耗(hao)的(de)(de)電(dian)(dian)(dian)(dian)量(liang)(liang)）這是官標的(de)(de)理論值，對實(shi)際使用(yong)沒(mei)有任何(he)意義，因為(wei)(wei)各人(ren)(ren)玩機(ji)的(de)(de)時(shi)間不(bu)(bu)同和(he)優化(hua)不(bu)(bu)同會(hui)有很大(da)(da)的(de)(de)差異，所以有些人(ren)(ren)在(zai)開屏或玩機(ji)時(shi)，因為(wei)(wei)使用(yong)的(de)(de)小(xiao)(xiao)(xiao)電(dian)(dian)(dian)(dian)流(liu)的(de)(de)充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)（低于(yu)手機(ji)電(dian)(dian)(dian)(dian)量(liang)(liang)消(xiao)耗(hao)瓦時(shi)）充(chong)(chong)不(bu)(bu)上(shang)(shang)電(dian)(dian)(dian)(dian)，而且，如(ru)果充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)電(dian)(dian)(dian)(dian)流(liu)過小(xiao)(xiao)(xiao)，電(dian)(dian)(dian)(dian)池會(hui)因為(wei)(wei)長時(shi)間充(chong)(chong)不(bu)(bu)到額定容量(liang)(liang)而對電(dian)(dian)(dian)(dian)池造(zao)成損(sun)害（當(dang)然這個長時(shi)間可(ke)能(neng)會(hui)很長，沒(mei)有有搜到相關評測資(zi)料），并(bing)有可(ke)能(neng)會(hui)燒(shao)壞充(chong)(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)。
那為什么大電流充電不會燒機器，這是因為充電電流是由電池和它本身所帶的充電保護電路IC決定的，和充電器無關，如果你所使用的充電器電流是5A的，因為機器充電保護電路已經把充電電流限制在一個安全的范圍，所以不會對電池損傷，有些手機上還帶了(le)保護電(dian)(dian)流(liu)電(dian)(dian)路(lu)，在接入過高電(dian)(dian)流(liu)時(shi)，會(hui)自動切斷(duan)充電(dian)(dian)電(dian)(dian)路(lu)，但是那不是絕對(dui)的，雖(sui)然有IC保護但是過大的電(dian)(dian)流(liu)，也有可(ke)能會(hui)讓(rang)電(dian)(dian)池(chi)(chi)鼓漲或(huo)爆炸，為了(le)保證電(dian)(dian)池(chi)(chi)的壽命和自己的安(an)全，不建議用(yong)超過3A的充電(dian)(dian)器對(dui)電(dian)(dian)池(chi)(chi)進行(xing)充電(dian)(dian)，更不建議用(yong)過小（500mah）的充電(dian)(dian)器對(dui)手機進行(xing)充電(dian)(dian)。
