電(dian)(dian)(dian)(dian)(dian)(dian)子技(ji)(ji)術(shu)(shu)是(shi)十(shi)九世紀末、二十(shi)世紀初開(kai)始發(fa)(fa)展(zhan)(zhan)起來的(de)新興技(ji)(ji)術(shu)(shu)，二十(shi)世紀發(fa)(fa)展(zhan)(zhan)最迅(xun)(xun)速(su)，應用最廣泛，成為近代(dai)科學(xue)技(ji)(ji)術(shu)(shu)發(fa)(fa)展(zhan)(zhan)的(de)一個(ge)重要標志。 第(di)一代(dai)電(dian)(dian)(dian)(dian)(dian)(dian)子產(chan)品(pin)以電(dian)(dian)(dian)(dian)(dian)(dian)子管(guan)為核心。四十(shi)年代(dai)末世界(jie)上(shang)誕(dan)生了第(di)一只(zhi)半導體三極管(guan)，它以小(xiao)巧、輕(qing)便、省(sheng)電(dian)(dian)(dian)(dian)(dian)(dian)、壽命(ming)長等(deng)特點，很(hen)(hen)快地被各國應用起來，在(zai)很(hen)(hen)大(da)范(fan)圍內取代(dai)了電(dian)(dian)(dian)(dian)(dian)(dian)子管(guan)。五十(shi)年代(dai)末期，世界(jie)上(shang)出現了第(di)一塊(kuai)集(ji)(ji)成電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)，它把許多晶體管(guan)等(deng)電(dian)(dian)(dian)(dian)(dian)(dian)子元件集(ji)(ji)成在(zai)一塊(kuai)硅芯(xin)片上(shang)，使(shi)電(dian)(dian)(dian)(dian)(dian)(dian)子產(chan)品(pin)向更(geng)小(xiao)型化發(fa)(fa)展(zhan)(zhan)。集(ji)(ji)成電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)從小(xiao)規(gui)模(mo)集(ji)(ji)成電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)迅(xun)(xun)速(su)發(fa)(fa)展(zhan)(zhan)到大(da)規(gui)模(mo)集(ji)(ji)成電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)和超大(da)規(gui)模(mo)集(ji)(ji)成電(dian)(dian)(dian)(dian)(dian)(dian)路(lu)，從而(er)使(shi)電(dian)(dian)(dian)(dian)(dian)(dian)子產(chan)品(pin)向著高(gao)效能(neng)低消耗(hao)、高(gao)精(jing)度(du)、高(gao)穩定、智能(neng)化的(de)方向發(fa)(fa)展(zhan)(zhan)。

小型便攜式電子產品采用的鋰離子電池或鋰聚合物電池的容量較小，大部分在400~1000mAh范圍內，與之配套的充電器的最大充電電流為450~1000mAh.由于電流不大，一般采用線性充電器。鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)的(de)(de)(de)(de)不(bu)足之處在于(yu)對充電(dian)(dian)(dian)(dian)(dian)(dian)器要(yao)(yao)求比較苛刻，需(xu)要(yao)(yao)保(bao)護(hu)電(dian)(dian)(dian)(dian)(dian)(dian)路。鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)要(yao)(yao)求的(de)(de)(de)(de)充電(dian)(dian)(dian)(dian)(dian)(dian)方式是(shi)恒流恒壓方式，為(wei)有(you)效(xiao)利用電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)容量，需(xu)將鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充電(dian)(dian)(dian)(dian)(dian)(dian)至最大電(dian)(dian)(dian)(dian)(dian)(dian)壓，但(dan)是(shi)過壓充電(dian)(dian)(dian)(dian)(dian)(dian)會造成電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)損(sun)壞，這就要(yao)(yao)求較高的(de)(de)(de)(de)控制精度。另外，對于(yu)電(dian)(dian)(dian)(dian)(dian)(dian)壓過低的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)需(xu)要(yao)(yao)進行預充，充電(dian)(dian)(dian)(dian)(dian)(dian)器最好帶有(you)熱保(bao)護(hu)和時間保(bao)護(hu)，為(wei)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)提供附加保(bao)護(hu)。因此，安全有(you)效(xiao)的(de)(de)(de)(de)鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充電(dian)(dian)(dian)(dian)(dian)(dian)器對于(yu)鋰離(li)(li)子電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)來說就是(shi)必須而且是(shi)必要(yao)(yao)的(de)(de)(de)(de)。

鋰離子電池充電器外接限流型充電電源和P溝道場效應管，可以對單節鋰離子電池進行安全有效的快充，其最大特點是在不使用電感的情況下仍能做到很低的功率耗散，采用8腳μMAX封裝。充電控制精度達0.75%,可以實現預充電，具有過壓保護和溫度保護功能，最長充電時間限制為鋰離子電池提供二次保護，鋰離子電池充電器的(de)浮充(chong)(chong)(chong)(chong)(chong)方式能(neng)夠使電(dian)(dian)(dian)(dian)池容量充(chong)(chong)(chong)(chong)(chong)至最大(da)。當(dang)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)源和(he)電(dian)(dian)(dian)(dian)池在正常的(de)工作溫度范圍內(nei)時(shi)，插入(ru)電(dian)(dian)(dian)(dian)池將啟動一次充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)過程;充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)結(jie)束(shu)的(de)條件是平(ping)均的(de)脈沖充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流達到快充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)流的(de)1%,或時(shi)間超出片上預置的(de)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)時(shi)間。鋰離(li)子電(dian)(dian)(dian)(dian)池充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)器能(neng)夠自動檢測充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)源，沒有電(dian)(dian)(dian)(dian)源時(shi)自動關斷以(yi)減少電(dian)(dian)(dian)(dian)池的(de)漏電(dian)(dian)(dian)(dian)。啟動快充(chong)(chong)(chong)(chong)(chong)后打開外接的(de)P型場(chang)效(xiao)應管(guan)，當(dang)檢測到電(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)壓(ya)達到設定(ding)的(de)門限(xian)時(shi)進入(ru)脈沖充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)方式，P溝道場(chang)效(xiao)應管(guan)打開的(de)時(shi)間會越來越短，充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)結(jie)束(shu)時(shi)，LED指示燈將會按12%的(de)周期閃爍(shuo)。

近年來，一些用電(dian)(dian)(dian)量(liang)(liang)(liang)稍(shao)大的便攜式(shi)電(dian)(dian)(dian)子(zi)產品(pin)(如便攜式(shi)DVD、礦燈(deng)、攝像機、便攜式(shi)測量(liang)(liang)(liang)儀器、小(xiao)型電(dian)(dian)(dian)動(dong)工具等)往(wang)往(wang)采(cai)用1500mAh到5400mAh容(rong)量(liang)(liang)(liang)的鋰(li)離子(zi)電(dian)(dian)(dian)池。若采(cai)用500~1000mA充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)充(chong)電(dian)(dian)(dian)器充(chong)電(dian)(dian)(dian)，則(ze)充(chong)電(dian)(dian)(dian)時間太長(chang)。

有人提出(chu)：能否在1A線性充(chong)電(dian)(dian)器(qi)電(dian)(dian)路中加一(yi)(yi)個(ge)擴(kuo)(kuo)流(liu)電(dian)(dian)路，使充(chong)電(dian)(dian)電(dian)(dian)流(liu)擴(kuo)(kuo)大到2~2.5A,解決3000~5400mAh容(rong)量鋰離(li)子(zi)電(dian)(dian)池的(de)充(chong)電(dian)(dian)問題。如(ru)果(guo)擴(kuo)(kuo)流(liu)的(de)充(chong)電(dian)(dian)器(qi)性能不錯(cuo)、電(dian)(dian)路簡單、成(cheng)本(ben)不高，這(zhe)是(shi)個(ge)好主意。筆者(zhe)就按這(zhe)一(yi)(yi)思路設(she)計一(yi)(yi)個(ge)擴(kuo)(kuo)流(liu)電(dian)(dian)路。這(zhe)電(dian)(dian)路采用(yong)型號為(wei)CN3056的(de)1A線性充(chong)電(dian)(dian)器(qi)為(wei)基(ji)礎，另外加上(shang)擴(kuo)(kuo)流(liu)電(dian)(dian)路及控制電(dian)(dian)路組(zu)成(cheng)。

CN3056簡介

CN3056組成(cheng)的(de)(de)充(chong)(chong)電(dian)器(qi)按恒流(liu)(liu)、恒壓(ya)模式(shi)(shi)充(chong)(chong)電(dian)，若(ruo)充(chong)(chong)電(dian)電(dian)池電(dian)壓(ya)<3V,則有小電(dian)流(liu)(liu)預充(chong)(chong)電(dian)模式(shi)(shi);充(chong)(chong)電(dian)電(dian)流(liu)(liu)可設定(ding)，最大充(chong)(chong)電(dian)電(dian)流(liu)(liu)為1A;精(jing)電(dian)密度4.2V±1%、有熱調節、欠(qian)壓(ya)鎖存(cun)及電(dian)池溫(wen)度檢測(ce)、超溫(wen)保護及充(chong)(chong)電(dian)狀態和(he)溫(wen)度超差指示功能;10引腳小尺寸DFN封(feng)裝(3mm×3mm)。CN3056是可以對單節鋰(li)離子或者(zhe)鋰(li)-聚合物電(dian)池進(jin)行(xing)恒流(liu)(liu)/恒壓(ya)充(chong)(chong)電(dian)的(de)(de)充(chong)(chong)電(dian)器(qi)電(dian)路(lu)。該器(qi)件(jian)內部包括功率晶(jing)體管，應用時(shi)不需(xu)要外部的(de)(de)電(dian)流(liu)(liu)檢測(ce)電(dian)阻和(he)阻流(liu)(liu)二極管

若充(chong)(chong)電(dian)(dian)率在(zai)0.5~1C之(zhi)間、電(dian)(dian)池的溫(wen)(wen)(wen)度在(zai)0~45℃之(zhi)間(室溫(wen)(wen)(wen)充(chong)(chong)電(dian)(dian))，則(ze)CN3056充(chong)(chong)電(dian)(dian)器(qi)電(dian)(dian)路中(zhong)可省(sheng)去電(dian)(dian)池溫(wen)(wen)(wen)度檢測電(dian)(dian)路及電(dian)(dian)池超溫(wen)(wen)(wen)指示電(dian)(dian)路(引腳TEMP及FAULT端(duan)接地)，電(dian)(dian)路如圖1所(suo)示。VIN是電(dian)(dian)源(yuan)輸入(ru)端(duan)、CE是使能端(duan)，(高電(dian)(dian)平有效);RISET為(wei)充(chong)(chong)電(dian)(dian)電(dian)(dian)流ICH設定電(dian)(dian)阻，RISET(Ω)=1800(V)/ICH(A);CHRG為(wei)充(chong)(chong)電(dian)(dian)狀態信號輸出(chu)端(duan)：充(chong)(chong)電(dian)(dian)時(shi)此(ci)端(duan)為(wei)高電(dian)(dian)平，LED亮;充(chong)(chong)電(dian)(dian)結束(shu)時(shi)此(ci)端(duan)為(wei)高阻抗，LED滅;電(dian)(dian)池未裝入(ru)或接觸不良(liang)，LED閃亮。