便攜式電(dian)(dian)(dian)源的(de)(de)應(ying)用(yong)(yong)范(fan)圍(wei)很廣，也很多樣化。產品包括(kuo)消耗(hao)uW級平均功率的(de)(de)無線傳感器節點以及可(ke)用(yong)(yong)小車(che)推著的(de)(de)、電(dian)(dian)(dian)池組(zu)耗(hao)電(dian)(dian)(dian)數(shu)百瓦-時(shi)的(de)(de)醫(yi)療或數(shu)據(ju)采集(ji)系統。不(bu)過，盡管應(ying)用(yong)(yong)種類很多，仍然出現了幾個趨(qu)勢，設計師日(ri)益(yi)需要(yao)給產品提供更(geng)大(da)的(de)(de)功率，以支持(chi)不(bu)斷增多的(de)(de)功能，同時(shi)也在(zai)考(kao)慮怎樣用(yong)(yong)任何可(ke)用(yong)(yong)電(dian)(dian)(dian)源給電(dian)(dian)(dian)池充電(dian)(dian)(dian)。要(yao)滿足(zu)第一種需求(qiu)，就要(yao)提高電(dian)(dian)(dian)池容量。不(bu)幸的(de)(de)是，用(yong)(yong)戶大(da)多比較心急，容量提高以后，還必須在(zai)一個合理的(de)(de)時(shi)間內充滿電(dian)(dian)(dian)，這(zhe)就導致要(yao)增大(da)充電(dian)(dian)(dian)電(dian)(dian)(dian)流。要(yao)滿足(zu)第二種需求(qiu)，就要(yao)求(qiu)電(dian)(dian)(dian)池充電(dian)(dian)(dian)解決方案提供極大(da)的(de)(de)靈活性。本文將更(geng)詳(xiang)細地討論這(zhe)些問(wen)題。

　　更大的功率

　　考慮一(yi)(yi)下(xia)新式(shi)(shi)手(shou)持式(shi)(shi)設備(bei)(bei)，面向消費者的(de)(de)(de)(de)(de)(de)(de)設備(bei)(bei)和工(gong)業設備(bei)(bei)都可能包(bao)括蜂(feng)窩電(dian)(dian)話調制解(jie)調器、Wi-Fi模(mo)塊、藍(lan)牙模(mo)塊、大尺寸背光(guang)照(zhao)明顯示屏(ping)…等等。很多(duo)手(shou)持式(shi)(shi)設備(bei)(bei)的(de)(de)(de)(de)(de)(de)(de)電(dian)(dian)源(yuan)(yuan)架(jia)構都與蜂(feng)窩電(dian)(dian)話的(de)(de)(de)(de)(de)(de)(de)非(fei)常(chang)相似。一(yi)(yi)般情況(kuang)下(xia)，用一(yi)(yi)個(ge)3.7V的(de)(de)(de)(de)(de)(de)(de)鋰離子電(dian)(dian)池(chi)(chi)作為主電(dian)(dian)源(yuan)(yuan)，因(yin)為鋰離子電(dian)(dian)池(chi)(chi)按重量(liang)和按體積的(de)(de)(de)(de)(de)(de)(de)能量(liang)密度(du)都很高(單位分別為Wh/kg和Wh/m3)。過去，很多(duo)大功率設備(bei)(bei)都采用7.4V鋰離子電(dian)(dian)池(chi)(chi)，以(yi)降低(di)電(dian)(dian)流要(yao)求，不過低(di)價5V電(dian)(dian)源(yuan)(yuan)管理(li)IC的(de)(de)(de)(de)(de)(de)(de)上市(shi)已經促使越(yue)來越(yue)多(duo)的(de)(de)(de)(de)(de)(de)(de)手(shou)持式(shi)(shi)設備(bei)(bei)采用了(le)電(dian)(dian)壓(ya)更(geng)低(di)的(de)(de)(de)(de)(de)(de)(de)架(jia)構。平板電(dian)(dian)腦(nao)很好地說(shuo)明了(le)這一(yi)(yi)點：一(yi)(yi)個(ge)典型的(de)(de)(de)(de)(de)(de)(de)平板電(dian)(dian)腦(nao)有極多(duo)的(de)(de)(de)(de)(de)(de)(de)功能以(yi)及非(fei)常(chang)大的(de)(de)(de)(de)(de)(de)(de)顯示屏(ping)(就便(bian)攜式(shi)(shi)設備(bei)(bei)而言)。用3.7V電(dian)(dian)池(chi)(chi)供電(dian)(dian)時(shi)，其容(rong)量(liang)必須以(yi)數(shu)千毫安(an)-小時(shi)計算(suan)。為了(le)在(zai)幾個(ge)小時(shi)內給(gei)這樣(yang)一(yi)(yi)個(ge)電(dian)(dian)池(chi)(chi)充滿電(dian)(dian)，需要(yao)數(shu)千mA的(de)(de)(de)(de)(de)(de)(de)充電(dian)(dian)電(dian)(dian)流。

　　然而，如果沒(mei)有大(da)(da)(da)(da)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)交流(liu)適(shi)配器(qi)，盡(jin)管(guan)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)這么高，也(ye)不能(neng)防止消費者用(yong)USB端口(kou)給大(da)(da)(da)(da)功(gong)率設備充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)想法(fa)。為了(le)滿足(zu)這種需求，當交流(liu)適(shi)配器(qi)可用(yong)時(shi)(shi)(shi)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)必須(xu)能(neng)以大(da)(da)(da)(da)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(>2A)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，而在沒(mei)有交流(liu)適(shi)配器(qi)可用(yong)時(shi)(shi)(shi)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)必須(xu)仍能(neng)高效地利用(yong)USB端口(kou)提供2.5W至4.5W功(gong)率。此外，器(qi)件必須(xu)保護(hu)敏感(gan)的(de)下游低壓(ya)組件免受可能(neng)出現(xian)過壓(ya)情況(kuang)所導致的(de)損壞(huai)，同時(shi)(shi)(shi)必須(xu)無縫地將(jiang)大(da)(da)(da)(da)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)從USB輸入、交流(liu)適(shi)配器(qi)或電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)傳(chuan)送到(dao)負載，并最大(da)(da)(da)(da)限(xian)度地降低功(gong)耗。另外，該IC還必須(xu)安全地管(guan)理電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)算法(fa)，并監視(shi)關(guan)鍵的(de)系統(tong)參(can)數。

　　戰勝單節電池(chi)供(gong)電的(de)便(bian)攜式產(chan)品在功率方面的(de)挑戰

　　盡(jin)管(guan)看似不(bu)可能找到(dao)能滿(man)足上述要求(qiu)的(de)(de)單個(ge)(ge)IC，不(bu)過(guo)看一下(xia)LTC4155，這(zhe)是一個(ge)(ge)大功率(lv)、I2C控制的(de)(de)高效率(lv)電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)通路(PowerPath?)管(guan)理(li)器(qi)、理(li)想二極管(guan)控制器(qi)和(he)(he)鋰(li)離子電(dian)(dian)(dian)(dian)(dian)池充電(dian)(dian)(dian)(dian)(dian)器(qi)。該(gai)IC用來從(cong)各種(zhong)5V電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)高效地傳送高達3A的(de)(de)電(dian)(dian)(dian)(dian)(dian)流，可產生超過(guo)3.5A的(de)(de)可用電(dian)(dian)(dian)(dian)(dian)流，以(yi)供(gong)電(dian)(dian)(dian)(dian)(dian)池充電(dian)(dian)(dian)(dian)(dian)和(he)(he)系(xi)統(tong)使(shi)用(參(can)見(jian)圖(tu)1)。LTC4155的(de)(de)效率(lv)為88%至(zhi)94%，因此即使(shi)電(dian)(dian)(dian)(dian)(dian)流值這(zhe)么大，該(gai)IC仍然可以(yi)減輕熱量(liang)預算限(xian)制(參(can)見(jian)圖(tu)2)。LTC4155的(de)(de)開(kai)關式(shi)電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)通路拓撲(pu)無縫(feng)地管(guan)理(li)從(cong)兩種(zhong)輸入(ru)電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)(例如一個(ge)(ge)交流適配器(qi)和(he)(he)一個(ge)(ge)USB端口)到(dao)設備中可再充電(dian)(dian)(dian)(dian)(dian)鋰(li)離子電(dian)(dian)(dian)(dian)(dian)池的(de)(de)配電(dian)(dian)(dian)(dian)(dian)，同時(shi)當輸入(ru)功率(lv)有限(xian)時(shi)，優(you)先為系(xi)統(tong)負載供(gong)電(dian)(dian)(dian)(dian)(dian)。

圖1：LTC4155的典型應用電路(lu)

圖2：LTC4155的典型(xing)效率

　　與(yu)典型的線性(xing)模式充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器相(xiang)比，LTC4155中開(kai)關穩壓器的作(zuo)用就像一(yi)個變壓器，允(yun)許VOUT上的負載電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)超過輸入電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)吸取(qu)的電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)，并極大地提高(gao)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的可用功(gong)率(lv)。前述例子說明了LTC4155怎(zen)樣才能以(yi)高(gao)達3.5A的電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)高(gao)效率(lv)地充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，以(yi)實現更(geng)快的充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)時(shi)間。與(yu)普通的開(kai)關型電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器不同，LTC4155可即時(shi)接(jie)通工作(zuo)，以(yi)確保(bao)即使(shi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池沒電(dian)(dian)(dian)(dian)(dian)(dian)(dian)或已深度放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，當一(yi)插上電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)插頭，系統電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)也立(li)即可用。

　　盡管是以(yi)很高(gao)的速率給電(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)，監(jian)視電(dian)(dian)(dian)(dian)池(chi)是否安(an)全也(ye)是很重要的。當電(dian)(dian)(dian)(dian)池(chi)溫(wen)度降至低于(yu)0°C或(huo)升至高(gao)于(yu)40°C[由一個外(wai)部負溫(wen)度系數(NTC)熱敏電(dian)(dian)(dian)(dian)阻測量]時，LTC4155將自動停(ting)止充(chong)電(dian)(dian)(dian)(dian)。除(chu)了這(zhe)種自主式(shi)功能，LTC4155還提供一個7位擴展(zhan)標(biao)度模數轉(zhuan)換器(ADC)，以(yi)大約1°C的分辨(bian)率監(jian)視電(dian)(dian)(dian)(dian)池(chi)溫(wen)度(參見圖3)。結合4個可(ke)用的浮置電(dian)(dian)(dian)(dian)壓設定值和15個電(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)設定值，該ADC可(ke)基于(yu)電(dian)(dian)(dian)(dian)池(chi)溫(wen)度來建(jian)立(li)定制的充(chong)電(dian)(dian)(dian)(dian)算法。

圖3：7位熱敏電阻器ADC顯示LTC4155的預置溫度(du)跳(tiao)變(bian)點

　　通過一個簡單的兩線I2C端口可獲得NTCADC的結果，從而能調節充電電流和電壓的設定值。該I2C端口通過控制16個輸入電流的設定值(包括USB2.0和3.0兼容設置)，還可提供USB兼容性。該通信總線允許LTC4155指示額外的狀態信息，例如輸入電源狀態、充電器狀態和故障狀態。由于支持(chi)USBOTG，因此無需任何額外(wai)的組(zu)件，就可以反過(guo)來向USB端口(kou)提供5V電源。

　　LTC4155的(de)(de)(de)雙路(lu)(lu)輸(shu)入(ru)、優(you)先級(ji)多路(lu)(lu)復用器(qi)(qi)可根(gen)據用戶(hu)定義的(de)(de)(de)優(you)先級(ji)(默認的(de)(de)(de)優(you)先級(ji)為適配器(qi)(qi)輸(shu)入(ru))自主地選擇最(zui)合(he)適的(de)(de)(de)輸(shu)入(ru)(即墻上適配器(qi)(qi)或(huo)(huo)USB)。過壓保護(OVP)電(dian)路(lu)(lu)同時保護兩個(ge)輸(shu)入(ru)，以免這些輸(shu)入(ru)因無(wu)意間(jian)加上的(de)(de)(de)高壓或(huo)(huo)反向電(dian)壓而(er)損壞。LTC4155的(de)(de)(de)理想(xiang)二極管控制器(qi)(qi)保證(zheng)即使輸(shu)入(ru)功率不足或(huo)(huo)未(wei)提(ti)供(gong)輸(shu)入(ru)功率時，也(ye)始(shi)終(zhong)可向VOUT提(ti)供(gong)足夠的(de)(de)(de)功率。

　　就平板電(dian)(dian)腦、工業(ye)條碼掃描器(qi)等很多便攜式(shi)應用而言，能管(guan)理兩個(ge)輸入(例如USB和交流適配器(qi))就足(zu)夠了(le)。不過，便攜式(shi)設備的設計師一直在(zai)尋求用任何可用電(dian)(dian)源都能給(gei)電(dian)(dian)池充(chong)電(dian)(dian)的方法

　　多種輸入源

　　用(yong)(yong)(yong)(yong)戶要用(yong)(yong)(yong)(yong)多種輸(shu)入(ru)源(yuan)(yuan)給(gei)(gei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)有幾個(ge)(ge)原因。有些(xie)(xie)應用(yong)(yong)(yong)(yong)也許(xu)需(xu)(xu)要擺脫電(dian)(dian)(dian)(dian)(dian)(dian)(dian)網的(de)(de)(de)(de)束縛，而靠太(tai)陽能(neng)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)板供電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。另一些(xie)(xie)應用(yong)(yong)(yong)(yong)則可(ke)能(neng)要求(qiu)能(neng)方便地(di)用(yong)(yong)(yong)(yong)交流適配器(qi)、汽(qi)車電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)或(huo)高(gao)(gao)壓工業及電(dian)(dian)(dian)(dian)(dian)(dian)(dian)信電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。無(wu)(wu)論出于何(he)種原因，這要求(qiu)都給(gei)(gei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)系統增加了(le)極大(da)(da)的(de)(de)(de)(de)負擔。大(da)(da)多數電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)都利用(yong)(yong)(yong)(yong)降(jiang)壓型(開關(guan)或(huo)線(xian)性(xing))架構，用(yong)(yong)(yong)(yong)高(gao)(gao)于電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)最高(gao)(gao)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓源(yuan)(yuan)給(gei)(gei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。以前的(de)(de)(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器(qi)產品輸(shu)入(ru)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓一般(ban)限(xian)制為(wei)(wei)大(da)(da)約30V。這樣的(de)(de)(de)(de)限(xian)制使設(she)計師無(wu)(wu)法將(jiang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)信電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)或(huo)者具42V開路電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓的(de)(de)(de)(de)太(tai)陽能(neng)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)板作為(wei)(wei)可(ke)行(xing)的(de)(de)(de)(de)輸(shu)入(ru)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)。在有些(xie)(xie)情況下，希(xi)望使用(yong)(yong)(yong)(yong)的(de)(de)(de)(de)輸(shu)入(ru)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓涵蓋(gai)了(le)高(gao)(gao)于和(he)低(di)于電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓的(de)(de)(de)(de)范圍(wei)。設(she)計一款應對此類難題的(de)(de)(de)(de)解決(jue)方案通常需(xu)(xu)要混合使用(yong)(yong)(yong)(yong)高(gao)(gao)精度的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流檢測放大(da)(da)器(qi)、ADC、一個(ge)(ge)用(yong)(yong)(yong)(yong)于控(kong)制充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)(de)(de)微處理器(qi)、一個(ge)(ge)高(gao)(gao)性(xing)能(neng)DC/DC轉換(huan)器(qi)以及一個(ge)(ge)理想二(er)極管或(huo)多路復用(yong)(yong)(yong)(yong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路。

　　強(qiang)大(da)的(de)充(chong)電解決方案提供無與倫比(bi)的(de)靈活性

　　LTC4000可將任何外部補償的DC/DC電源轉換成具電源通路(PowerPath?)控制的全功能電池充電器。可由LTC4000驅動的典型DC/DC轉換器拓撲包括但不限于：降壓、升壓、降壓-升壓、SEPIC和反激式拓撲。該器件提供精確的輸入和充電電流調節，在3V至60V的寬輸入和輸出電壓范圍內工作，實現了與各種不同的輸入電壓源、以及不同尺寸和化學組成的電池組的兼容性。由于該器件的通用型配置，因此其典型應用十分廣泛，包括高功率電池充電器系(xi)統、高性能便攜式儀器、電池(chi)(chi)后備(bei)系(xi)統、配有工(gong)業(ye)電池(chi)(chi)的(de)設備(bei)以及筆(bi)記(ji)(ji)本(ben)/小型筆(bi)記(ji)(ji)本(ben)電腦。

　　除了(le)可以(yi)(yi)與很多不同的(de)(de)(de)DC/DC拓撲(pu)結合，LTC4000的(de)(de)(de)高壓能(neng)力(li)還允許該器件構成強(qiang)大和(he)幾乎可使用(yong)任何輸入電(dian)(dian)源(參見圖4和(he)圖5)的(de)(de)(de)電(dian)(dian)池充(chong)電(dian)(dian)解決方案。為(wei)了(le)確保來(lai)自這些輸入的(de)(de)(de)功(gong)率傳送給合適(shi)的(de)(de)(de)負載，LTC4000采用(yong)了(le)一(yi)種智能(neng)電(dian)(dian)源通路(lu)拓撲(pu)，當輸入功(gong)率有限時，該拓撲(pu)可優(you)先為(wei)系(xi)統(tong)負載供(gong)電(dian)(dian)。LTC4000控制外部(bu)PFET，以(yi)(yi)提供(gong)低(di)損耗(hao)反(fan)向電(dian)(dian)流(liu)(liu)保護、電(dian)(dian)池的(de)(de)(de)低(di)損耗(hao)充(chong)電(dian)(dian)和(he)放電(dian)(dian)以(yi)(yi)及(ji)即時接(jie)通工作，這樣就可以(yi)(yi)確保即使在電(dian)(dian)池沒電(dian)(dian)或(huo)深度放電(dian)(dian)時，當一(yi)插上電(dian)(dian)源，系(xi)統(tong)電(dian)(dian)源就能(neng)立即可用(yong)。外部(bu)檢測電(dian)(dian)阻器提供(gong)輸入電(dian)(dian)流(liu)(liu)和(he)電(dian)(dian)池充(chong)電(dian)(dian)電(dian)(dian)流(liu)(liu)信息，從(cong)而使LTC4000能(neng)與涵蓋mW至kW功(gong)率范圍的(de)(de)(de)轉換(huan)器一(yi)起使用(yong)。

圖4：LTC4000和LTC3789：6V至36V_IN、4節5A鋰離子電池(chi)充電器(qi)

圖(tu)5：圖(tu)4電路中(zhong)系統負載為4A時效率隨VIN的變化

　　LTC4000的全功能電池充電控制器可為各種化學組成的電池充電，包括鋰離子/聚合物/磷酸、密封鉛酸(SLA)和鎳化學組成。該電池充電器還提供(gong)精確的電(dian)流(liu)檢測(ce)功能，從而在大電(dian)流(liu)應用情(qing)況下(xia)允許較(jiao)低的檢測(ce)電(dian)壓。

　　結論

　　新式便(bian)攜式產品設(she)計(ji)師(shi)的工作極(ji)富挑戰(zhan)性(xing)，尤其是涉(she)及到(dao)電(dian)(dian)(dian)源時。客戶不斷(duan)要求(qiu)更多(duo)功能以導(dao)致需要更大(da)的功率，結果是電(dian)(dian)(dian)池(chi)越(yue)來越(yue)大(da)。同時，客戶希望(wang)可(ke)方(fang)便(bian)地(di)用(yong)幾乎(hu)任何可(ke)用(yong)的電(dian)(dian)(dian)源給這些(xie)電(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)。盡管便(bian)攜式電(dian)(dian)(dian)源領域的這些(xie)趨勢造成了設(she)計(ji)挑戰(zhan)，但是LTC4155和LTC4000讓設(she)計(ji)工作變得簡(jian)單多(duo)了。在(zai)低壓系統中，LTC4155高(gao)(gao)效率地(di)提供(gong)(gong)高(gao)(gao)達3.5A的充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流，而(er)且(qie)提供(gong)(gong)很多(duo)高(gao)(gao)性(xing)能功能。LTC4000可(ke)構成強大(da)的充(chong)電(dian)(dian)(dian)解決方(fang)案，而(er)且(qie)幾乎(hu)可(ke)使用(yong)任何輸入(ru)，從而(er)提供(gong)(gong)了無與倫比的性(xing)能和靈(ling)活性(xing)。