【手機充電器(qi)】手機充電器(qi)電路圖講(jiang)解(jie) 手機充電器(qi)輸出電流多少合(he)適
手機充電(dian)器電(dian)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(jiao)流(liu)輸(shu)入，一(yi)端經過一(yi)個4007半波整流(liu)，另一端經過一個(ge)10歐(ou)的電(dian)阻后，由(you)10uF電容(rong)濾波。這個10歐的(de)電阻用來(lai)做保護的(de)，如果后面出現故障等導(dao)致過流(liu)，那么(me)這(zhe)個電阻將被燒斷(duan)，從而(er)避免引起更大的(de)故障。右邊的(de)4007、4700pF電容、82KΩ電阻，構成一個高壓吸收電路，當開關管13003關斷時，負責吸(xi)收線圈上的感應(ying)電(dian)壓，從而防止(zhi)高(gao)壓加到開關管13003上而導致擊(ji)穿。13003為開(kai)關管（完整的名應(ying)該是(shi)MJE13003），耐(nai)壓400V，集電極最大電流1.5A，最大集電極功耗(hao)為14W，用來(lai)控制原邊繞組(zu)與電源之間的(de)(de)通(tong)(tong)、斷。當(dang)原邊繞組(zu)不(bu)(bu)停的(de)(de)通(tong)(tong)斷時(shi)，就(jiu)會在(zai)開關(guan)變(bian)壓器(qi)中(zhong)形成(cheng)變(bian)化的(de)(de)磁場，從而在(zai)次(ci)級繞組(zu)中(zhong)產(chan)生感應電壓。由于圖(tu)中(zhong)沒有標(biao)明(ming)繞組(zu)的(de)(de)同名端，所以不(bu)(bu)能(neng)看出是正(zheng)激式(shi)還是反激式(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為啟動電阻，給開關管提供啟動用的(de)基(ji)極電流。13003下方的10Ω電阻(zu)為(wei)電流取(qu)樣電阻(zu)，電流經取(qu)樣后變成(cheng)電壓（其值(zhi)為(wei)10*I），這電壓經二極管4148后，加至(zhi)三極管(guan)C945的基極上(shang)。當取樣(yang)電(dian)壓大(da)約大(da)于1.4V，即開關管電流大于0.14A時，三極管(guan)C945導通，從而將(jiang)開關管13003的基極(ji)電(dian)(dian)壓拉(la)低，從(cong)而集電(dian)(dian)極(ji)電(dian)(dian)流減小，這樣(yang)就限制了開關(guan)的電(dian)(dian)流，防止電(dian)(dian)流過大而燒(shao)毀（其實這是一(yi)個恒流結構，將開關(guan)管的最大電(dian)(dian)流限制在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(rong)濾(lv)波后形(xing)成取(qu)樣(yang)電壓。為了分析方(fang)便，我們(men)取(qu)三極管C945發射(she)極一端(duan)為地。那么這取(qu)樣(yang)電壓(ya)就是負的（-4V左右），并且輸出(chu)電(dian)壓(ya)越(yue)高時，采樣電(dian)壓(ya)越(yue)負。取樣電(dian)壓(ya)經過6.2V穩(wen)壓二(er)極管后，加至開關管13003的(de)基極。前面說了，當輸出電(dian)壓(ya)越高時(shi)，那么取樣(yang)電(dian)壓(ya)就越負，當負到一定程度后，6.2V穩壓二(er)極管被擊穿(chuan)，從而將開關(guan)13003的(de)(de)基極電位拉(la)低，這將導致開關管(guan)斷開或者推遲(chi)開關的(de)(de)導通(tong)，從而控(kong)制了能(neng)量輸入到(dao)變壓器中，也就控(kong)制了輸出(chu)電壓的(de)(de)升高，實現了穩(wen)壓輸出(chu)的(de)(de)功能(neng)。
而下方的1KΩ電(dian)阻跟串聯的2700pF電容(rong)，則是正反饋支路，從(cong)取(qu)樣繞組中取(qu)出(chu)感(gan)應電壓，加到開(kai)關管(guan)(guan)的(de)基(ji)極(ji)上，以維(wei)持振蕩(dang)。右邊的(de)次級繞組就沒有太(tai)多好說的(de)了，經二(er)極(ji)管(guan)(guan)RF93整流，220uF電容濾波后輸出6V的(de)電壓。沒找到二極管RF93的資料(liao)，估(gu)計是(shi)一個快速回(hui)復管，例(li)如肖特基二(er)極管等，因(yin)為開關電(dian)源的工作(zuo)頻率(lv)較高，所以(yi)需(xu)要工作(zuo)頻率(lv)的二(er)極管。這里(li)可以(yi)用(yong)常見的1N5816、1N5817等肖特基二極管(guan)代替(ti)。
同樣因為頻率高(gao)的(de)原因，變壓器(qi)也必須(xu)使(shi)用高(gao)頻開關變壓器(qi)，鐵心一般為高(gao)頻鐵氧體(ti)磁芯，具有高(gao)的(de)電阻率，以減小渦流。
手機充電器輸出電流多少合適
手機電(dian)池容量基本(ben)是定型的(de)，電(dian)池的(de)充電(dian)時(shi)間跟充電(dian)電(dian)流大(da)小息息相(xiang)關，在同(tong)等充電(dian)電(dian)流下，電(dian)池容量越大(da)所(suo)需(xu)的(de)充電(dian)時(shi)間越長，同(tong)理，充電(dian)電(dian)流越大(da)，所(suo)需(xu)的(de)充電(dian)時(shi)間越短。
如果充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)所(suo)能提供的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流小(xiao)(xiao)于原(yuan)裝(zhuang)(zhuang)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)標(biao)準電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)時(shi)(shi)間(jian)勢(shi)必(bi)要延長(chang)，如1830毫安(an)的(de)(de)容(rong)(rong)(rong)量(liang)，原(yuan)裝(zhuang)(zhuang)的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)是(shi)(shi)1.2安(an)的(de)(de)，那么就(jiu)需要4小(xiao)(xiao)時(shi)(shi)左右才能將一塊完全沒(mei)(mei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)滿，而(er)再小(xiao)(xiao)一點電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)使用(yong)的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)時(shi)(shi)間(jian)會更長(chang)，如果電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流過小(xiao)(xiao)還(huan)會充(chong)不上(shang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，大家可能沒(mei)(mei)有注意到(dao)在原(yuan)裝(zhuang)(zhuang)的(de)(de)小(xiao)(xiao)6電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)上(shang)容(rong)(rong)(rong)量(liang)后(hou)面還(huan)有個7.0wh，1830毫mah/7.0wh，后(hou)面的(de)(de)7.0wh指的(de)(de)是(shi)(shi)瓦(wa)時(shi)(shi)，mah（毫安(an)時(shi)(shi)）和wh（瓦(wa)時(shi)(shi)）是(shi)(shi)比(bi)較常(chang)見的(de)(de)2種(zhong)表(biao)示(shi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)容(rong)(rong)(rong)量(liang)的(de)(de)方式(shi)，用(yong)mah乘以電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)額定電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)就(jiu)等(deng)于wh，以小(xiao)(xiao)6的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)為(wei)(wei)例(li)就(jiu)是(shi)(shi)1.83*3.7=12.81瓦(wa)時(shi)(shi)（指的(de)(de)是(shi)(shi)每小(xiao)(xiao)時(shi)(shi)消(xiao)耗的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)）這是(shi)(shi)官標(biao)的(de)(de)理論(lun)值，對(dui)實際使用(yong)沒(mei)(mei)有任何意義，因為(wei)(wei)各人(ren)玩機的(de)(de)時(shi)(shi)間(jian)不同和優化不同會有很大的(de)(de)差(cha)異，所(suo)以有些(xie)人(ren)在開屏或(huo)玩機時(shi)(shi)，因為(wei)(wei)使用(yong)的(de)(de)小(xiao)(xiao)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)（低于手機電(dian)(dian)(dian)(dian)(dian)(dian)(dian)量(liang)消(xiao)耗瓦(wa)時(shi)(shi)）充(chong)不上(shang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，而(er)且，如果充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流過小(xiao)(xiao)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)會因為(wei)(wei)長(chang)時(shi)(shi)間(jian)充(chong)不到(dao)額定容(rong)(rong)(rong)量(liang)而(er)對(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)造成(cheng)損害（當然(ran)這個長(chang)時(shi)(shi)間(jian)可能會很長(chang)，沒(mei)(mei)有有搜(sou)到(dao)相關評測資料），并有可能會燒壞充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(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(shang)還帶了保(bao)護(hu)電(dian)(dian)流電(dian)(dian)路(lu)，在(zai)接(jie)入過高電(dian)(dian)流時，會自動切斷充(chong)電(dian)(dian)電(dian)(dian)路(lu)，但是那不(bu)是絕對(dui)(dui)的(de)，雖然有IC保(bao)護(hu)但是過大的(de)電(dian)(dian)流，也有可能會讓(rang)電(dian)(dian)池鼓漲或爆炸，為(wei)了保(bao)證(zheng)電(dian)(dian)池的(de)壽命和自己的(de)安全，不(bu)建(jian)議用超(chao)過3A的(de)充(chong)電(dian)(dian)器(qi)對(dui)(dui)電(dian)(dian)池進(jin)行充(chong)電(dian)(dian)，更不(bu)建(jian)議用過小(xiao)（500mah）的(de)充(chong)電(dian)(dian)器(qi)對(dui)(dui)手機(ji)進(jin)行充(chong)電(dian)(dian)。
