【手(shou)機充(chong)電(dian)器(qi)】手(shou)機充(chong)電(dian)器(qi)電(dian)路圖講解 手(shou)機充(chong)電(dian)器(qi)輸出電(dian)流多少合適
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(ru)，一(yi)端經過(guo)一(yi)個(ge)4007半波整(zheng)流，另一(yi)端經過一(yi)個10歐的電阻(zu)后，由10uF電容濾波。這個10歐的(de)電阻(zu)(zu)用來做保護的(de)，如果后面(mian)出現故障等導致過流，那么這(zhe)個電阻(zu)(zu)將(jiang)被燒斷，從(cong)而避免引起更大的(de)故障。右邊的(de)4007、4700pF電容、82KΩ電阻，構成一個高壓吸(xi)收電路，當開關管13003關(guan)斷時，負責吸收(shou)線圈(quan)上的感(gan)應電壓(ya)，從而防止高壓(ya)加到開關(guan)管13003上而導(dao)致擊(ji)穿。13003為(wei)開(kai)關管（完整的(de)名(ming)應該是MJE13003），耐壓400V，集電(dian)(dian)極最大電(dian)(dian)流1.5A，最大集電極功耗為14W，用(yong)來控制原邊繞(rao)組(zu)(zu)與電源(yuan)之間的通、斷。當(dang)原邊繞(rao)組(zu)(zu)不(bu)停的通斷時，就會在開關變壓器(qi)中(zhong)形(xing)成變化的磁場，從而在次級繞(rao)組(zu)(zu)中(zhong)產生感應(ying)電壓。由于圖中(zhong)沒有標明(ming)繞(rao)組(zu)(zu)的同名端(duan)，所以不(bu)能看出是正激(ji)式(shi)還是反激(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(wei)啟動電阻，給開關管提(ti)供啟動用的基極(ji)電流。13003下方的10Ω電(dian)阻為電(dian)流取(qu)樣電(dian)阻，電(dian)流經(jing)取(qu)樣后變成電(dian)壓（其(qi)值為10*I），這(zhe)電壓經二(er)極管4148后，加至三極(ji)管C945的基極上。當取樣電壓大(da)約大(da)于1.4V，即(ji)開關管(guan)電流大(da)于0.14A時，三極(ji)管C945導通，從而將(jiang)開關管13003的基極電(dian)(dian)(dian)壓(ya)拉低，從而集電(dian)(dian)(dian)極電(dian)(dian)(dian)流減小，這樣就限制(zhi)(zhi)了開關的電(dian)(dian)(dian)流，防止(zhi)電(dian)(dian)(dian)流過大而燒毀（其實這是一個恒流結構，將開關管的最大電(dian)(dian)(dian)流限制(zhi)(zhi)在(zai)140mA左右）。
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(zheng)流，22uF電容濾波后形成取樣(yang)電壓。為(wei)了分析方(fang)便(bian)，我們取三極(ji)管C945發(fa)射極一端為地。那么(me)這取(qu)樣電壓就是負的(de)（-4V左右），并且輸出電(dian)壓(ya)越(yue)高(gao)時(shi)，采樣電(dian)壓(ya)越(yue)負。取樣電(dian)壓(ya)經過6.2V穩壓二極管后，加至(zhi)開關(guan)管13003的基極。前面說了(le)，當輸出電(dian)壓(ya)越高時，那(nei)么取樣(yang)電(dian)壓(ya)就越負，當負到一定程度后，6.2V穩壓(ya)二極管被擊穿，從而將開關(guan)13003的(de)基極電位拉(la)低，這(zhe)將導致開關(guan)管斷開或者推遲開關(guan)的(de)導通(tong)，從而控制了能量輸入到變壓器(qi)中，也就控制了輸出(chu)電壓的(de)升高，實現了穩壓輸出(chu)的(de)功(gong)能。
而下方的1KΩ電阻跟串聯的2700pF電容，則(ze)是(shi)正反饋支路(lu)，從取樣繞組中取出感(gan)應電壓(ya)，加到開(kai)關管的(de)基極上，以維(wei)持振蕩。右邊的(de)次級繞組就沒有太多好說的(de)了，經二(er)極管RF93整流(liu)，220uF電(dian)容濾波后輸出6V的電壓。沒找到二(er)極管RF93的(de)資料，估計是一(yi)個快速(su)回復管(guan)，例如(ru)肖(xiao)特基二極管(guan)等，因為開關電源(yuan)的(de)工(gong)作頻率較高，所以(yi)需要工(gong)作頻率的(de)二極管(guan)。這里可以(yi)用常見的(de)1N5816、1N5817等肖特(te)基二極管代替。
同樣(yang)因(yin)為頻(pin)率高(gao)的原因(yin)，變(bian)壓器也必須使用(yong)高(gao)頻(pin)開關(guan)變(bian)壓器，鐵(tie)心(xin)一般為高(gao)頻(pin)鐵(tie)氧體磁芯，具有(you)高(gao)的電(dian)阻率，以減小渦流。
手機充電器輸出電流多少合適
手機電(dian)(dian)(dian)池(chi)容量(liang)基本是定型的(de)(de)，電(dian)(dian)(dian)池(chi)的(de)(de)充(chong)電(dian)(dian)(dian)時間跟充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)(liu)大小息息相關，在同等充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)(liu)下，電(dian)(dian)(dian)池(chi)容量(liang)越大所需的(de)(de)充(chong)電(dian)(dian)(dian)時間越長(chang)，同理，充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)(liu)越大，所需的(de)(de)充(chong)電(dian)(dian)(dian)時間越短。
如(ru)(ru)果(guo)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)所能(neng)提供的(de)電(dian)(dian)(dian)流小于原(yuan)裝充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)標準電(dian)(dian)(dian)流，充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)時(shi)(shi)(shi)間(jian)勢必要延長，如(ru)(ru)1830毫安(an)(an)的(de)容(rong)量(liang)(liang)，原(yuan)裝的(de)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)是(shi)1.2安(an)(an)的(de)，那么(me)就需要4小時(shi)(shi)(shi)左右才(cai)能(neng)將一塊(kuai)完(wan)全沒電(dian)(dian)(dian)的(de)電(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)(chong)滿，而(er)(er)再小一點電(dian)(dian)(dian)流的(de)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)使(shi)用的(de)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)時(shi)(shi)(shi)間(jian)會(hui)更(geng)長，如(ru)(ru)果(guo)電(dian)(dian)(dian)流過小還(huan)(huan)會(hui)充(chong)(chong)(chong)(chong)不上(shang)電(dian)(dian)(dian)，大家可能(neng)沒有注意(yi)到(dao)在原(yuan)裝的(de)小6電(dian)(dian)(dian)池(chi)上(shang)容(rong)量(liang)(liang)后面還(huan)(huan)有個(ge)(ge)7.0wh，1830毫mah/7.0wh，后面的(de)7.0wh指的(de)是(shi)瓦時(shi)(shi)(shi)，mah（毫安(an)(an)時(shi)(shi)(shi)）和(he)wh（瓦時(shi)(shi)(shi)）是(shi)比(bi)較常見的(de)2種表(biao)示(shi)電(dian)(dian)(dian)池(chi)容(rong)量(liang)(liang)的(de)方(fang)式(shi)，用mah乘以電(dian)(dian)(dian)池(chi)額定電(dian)(dian)(dian)壓就等于wh，以小6的(de)電(dian)(dian)(dian)池(chi)為例就是(shi)1.83*3.7=12.81瓦時(shi)(shi)(shi)（指的(de)是(shi)每(mei)小時(shi)(shi)(shi)消耗的(de)電(dian)(dian)(dian)量(liang)(liang)）這是(shi)官標的(de)理(li)論(lun)值，對實際使(shi)用沒有任何意(yi)義，因為各人(ren)(ren)玩(wan)機(ji)的(de)時(shi)(shi)(shi)間(jian)不同和(he)優化不同會(hui)有很(hen)大的(de)差異，所以有些(xie)人(ren)(ren)在開屏或(huo)玩(wan)機(ji)時(shi)(shi)(shi)，因為使(shi)用的(de)小電(dian)(dian)(dian)流的(de)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)（低(di)于手機(ji)電(dian)(dian)(dian)量(liang)(liang)消耗瓦時(shi)(shi)(shi)）充(chong)(chong)(chong)(chong)不上(shang)電(dian)(dian)(dian)，而(er)(er)且，如(ru)(ru)果(guo)充(chong)(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)電(dian)(dian)(dian)流過小，電(dian)(dian)(dian)池(chi)會(hui)因為長時(shi)(shi)(shi)間(jian)充(chong)(chong)(chong)(chong)不到(dao)額定容(rong)量(liang)(liang)而(er)(er)對電(dian)(dian)(dian)池(chi)造成損害（當然這個(ge)(ge)長時(shi)(shi)(shi)間(jian)可能(neng)會(hui)很(hen)長，沒有有搜(sou)到(dao)相關評測資料），并有可能(neng)會(hui)燒壞(huai)充(chong)(chong)(chong)(chong)電(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(dai)了保(bao)護電(dian)(dian)流(liu)電(dian)(dian)路(lu)，在接(jie)入過高電(dian)(dian)流(liu)時，會自動切斷充電(dian)(dian)電(dian)(dian)路(lu)，但是(shi)那(nei)不(bu)是(shi)絕對的(de)，雖然有(you)IC保(bao)護但是(shi)過大(da)的(de)電(dian)(dian)流(liu)，也有(you)可能會讓電(dian)(dian)池(chi)鼓漲或爆炸，為了保(bao)證電(dian)(dian)池(chi)的(de)壽命和自己的(de)安(an)全，不(bu)建議(yi)用(yong)超過3A的(de)充電(dian)(dian)器對電(dian)(dian)池(chi)進(jin)行充電(dian)(dian)，更不(bu)建議(yi)用(yong)過小（500mah）的(de)充電(dian)(dian)器對手機進(jin)行充電(dian)(dian)。
