1、近十年來(lai)(lai)，隨(sui)(sui)著各種(zhong)便攜(xie)式設備(bei)（如手(shou)機(ji)(ji)、筆記本電(dian)腦 、攝像機(ji)(ji) 、數碼相(xiang)機(ji)(ji) 、PDA 等）的不(bu)斷推出 ，對(dui)電(dian)池的要求也隨(sui)(sui)之提高。以(yi)(yi)前(qian)，在這類(lei)應用(yong)中 ，NiMH電(dian)池和(he)NiCD電(dian)池，以(yi)(yi)其(qi)低價格(ge)占有較(jiao)大(da)優勢；但隨(sui)(sui)著便攜(xie)式設備(bei)對(dui)體積/重量的要求越(yue)(yue)來(lai)(lai)越(yue)(yue)苛(ke)刻(ke)，工作(zuo)和(he)待機(ji)(ji)時間(jian)越(yue)(yue)來(lai)(lai)越(yue)(yue)長以(yi)(yi)及Li電(dian)池成本的不(bu)斷降低，使 Li電(dian)池的優勢性(xing)能(neng)在這類(lei)應用(yong)中得(de)以(yi)(yi)充分的展(zhan)示，被廣(guang)大(da)電(dian)子設計(ji)工程師和(he)消(xiao)費者(zhe)所接(jie)受。隨(sui)(sui)著Li電(dian)池性(xing)能(neng)的不(bu)斷提高和(he)成本的進一(yi)步降低 ，Li電(dian)池將在許(xu)多應用(yong)中取代(dai)NiCD和(he)NiMH電(dian)池 。

　　雖然(ran)鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)有以上種種優點(dian)和(he)良好的(de)(de)市場前景，但(dan)它對充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路的(de)(de)要(yao)求比較高(gao)，在(zai)使(shi)用過程(cheng)中要(yao)避免出(chu)(chu)現過充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)和(he)過放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)現象。鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)過程(cheng)如(ru)圖１所(suo)示(shi)，在(zai)一(yi)(yi)個充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)周期內，鋰電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)在(zai)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)開始之(zhi)前需(xu)要(yao)檢測(ce)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓和(he)溫(wen)度(du)，判斷是否(fou)可充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，如(ru)果電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓或(huo)(huo)溫(wen)度(du)超出(chu)(chu)允許范(fan)圍，則禁(jin)止(zhi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。每節電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)的(de)(de)允許充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓為2.5-4.2V，溫(wen)度(du)為2.5-50℃。在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)處(chu)于深放電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)情況下，必須要(yao)求充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器具有預充(chong)(chong)(chong)(chong)(chong)過程(cheng)，使(shi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)滿(man)足快(kuai)速充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)條件，然(ran)后根據電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)廠商推薦的(de)(de)快(kuai)速充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)速度(du)對電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)進(jin)行恒(heng)流(liu)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓緩慢上升(sheng)；一(yi)(yi)旦電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓達(da)到(dao)所(suo)設定的(de)(de)終止(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓（一(yi)(yi)般為 4.1V 或(huo)(huo)4.2V），恒(heng)流(liu)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)終止(zhi)，充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)快(kuai)速衰(shuai)減，充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)進(jin)入滿(man)充(chong)(chong)(chong)(chong)(chong)過程(cheng)；在(zai)滿(man)充(chong)(chong)(chong)(chong)(chong)過程(cheng)中，充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)逐漸衰(shuai)減，直(zhi)到(dao)滿(man)充(chong)(chong)(chong)(chong)(chong)時(shi)間超時(shi)，轉入頂端(duan)截(jie)止(zhi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)；頂端(duan)截(jie)止(zhi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)時(shi)，充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器以極小的(de)(de)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)為電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)補充(chong)(chong)(chong)(chong)(chong)能量；頂端(duan)截(jie)止(zhi)充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)一(yi)(yi)段(duan)時(shi)間后，關閉充(chong)(chong)(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。

2　MAX1501簡介
　　
　　MAXIM公司(si)的(de)MAX1501是一種(zhong)全新的(de)溫度調節線(xian)性充(chong)電(dian)器(qi)采(cai)用16引(yin)腳(jiao)TQFN封(feng)裝，可為鋰離(li)子、鎳(nie)鎘、鎳(nie)氫電(dian)池進(jin)行(xing)充(chong)電(dian).MAX1501的(de)特點及(ji)其引(yin)腳(jiao)功能(neng)。它具有如下特點：

　　1.獨立運行或由微(wei)處理(li)器控制的(de)線性充電方案；

　　2.輸入大于6.5v時充(chong)電停止；

　　3.電(dian)流檢測監視器輸(shu)出(chu)；

　　4.電(dian)池(chi)電(dian)壓下(xia)降(jiang)4v以下(xia)后自(zi)動啟動充電(dian)；

　　5.無(wu)電池(chi)時仍然(ran)保持穩定輸出；

　　6.集成(cheng)了PMOSFET.反向(xiang)阻斷二極管和(he)檢測電流(liu)電阻；

　　7.薄(bo)型QFN封裝的多化學類型充(chong)電器(qi)。

3　MAX1501引腳功能

　　INP：高電(dian)流(liu)充電(dian)輸(shu)入；

　　IN: 低電流充電輸(shu)入；

　　GND： 地.連(lian)接外(wai)部開關到地；

　　SETI：電流傳(chuan)感(gan)跨導放大輸出；

　　VL： 線性輸出調整(zheng)器；

　　TMAX： 輸入最大充電時間(jian)選(xuan)擇(ze)(僅對max1501)；

　　IC：　 MAX1501Z的(de)內部連接.隨(sui)浮動(dong)；

　　FULLI： 最(zui)大關閉電流選擇輸入；

　　TEMP：衰耗溫度選擇輸入；
　　

4　鋰離子電池充電器的研制

　　MAX1501的最典(dian)型的應用是能夠用10%的快速充(chong)(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流對鋰離子(zi)電(dian)(dian)(dian)池(chi)進行預充(chong)(chong)(chong)電(dian)(dian)(dian)，用一(yi)個軟(ruan)啟動系統持續增(zeng)加充(chong)(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流。以(yi)每(mei)20ms增(zeng)加10%直(zhi)到電(dian)(dian)(dian)壓(ya)達到2.8V，當電(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)壓(ya)達到規格電(dian)(dian)(dian)壓(ya)4.1V/4.2V時進入常壓(ya)狀態并且減少充(chong)(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流。在SETI與(yu)地之間(jian)設置一(yi)個晶體管(guan)來控制快速充(chong)(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流，并且通(tong)過減少輸入電(dian)(dian)(dian)流使MAX1501遠離過熱，溫度調節電(dian)(dian)(dian)路調節MAX1501的溫度。當到達頂端關斷(duan)電(dian)(dian)(dian)流的關斷(duan)值時RLED腳作用一(yi)個高阻抗

進(jin)入低(di)(di)維護狀(zhuang)態。 當電池電壓低(di)(di)與95%時，通過設置(zhi)SELV可以自(zi)動進(jin)行在充電。

　　（1）設(she)置充電電流

　　設定電阻(zu)充(chong)電電流根據下列公式

　　（2）設置電容(rong)

　　為了獲得合(he)適的穩定(ding)性，可以用一(yi)個(ge)陶(tao)瓷(ci)電(dian)(dian)容(rong)(rong)(rong)最常用10uF 5R陶(tao)瓷(ci)電(dian)(dian)容(rong)(rong)(rong)來連接(jie)BATT到GND。將IN和INP連接(jie)起(qi)來并且到GND用1uF的陶(tao)瓷(ci)電(dian)(dian)容(rong)(rong)(rong)。由于(yu)過高輸入(ru)(ru)電(dian)(dian)壓(ya)或過高充電(dian)(dian)電(dian)(dian)流(liu)，可用更大的輸入(ru)(ru)途徑(jing)電(dian)(dian)容(rong)(rong)(rong)來降低噪聲。

　　（3）設置溫度調節

　　在(zai)邏輯輸入條件下設置規則的(de)死(si)機溫度(du)，MAX1501通過(guo)降低充電(dian)電(dian)流來(lai)限(xian)制由TEMP設定的(de)死(si)機溫度(du)值。MAX1501運行正(zheng)常，溫度(du)環路不會(hui)顯示異常情(qing)況(kuang)。TEMP允許在(zai)提供(gong)過(guo)多(duo)的(de)能量損失的(de)保護的(de)前提下將充電(dian)電(dian)流擴展到(dao)最(zui)大限(xian)度(du)。

　　（4）設置充電時(shi)間

　　在TMAX邏輯輸入條件下(xia)設(she)置(zhi)(zhi)最(zui)大充(chong)(chong)電(dian)(dian)時(shi)(shi)間。TMAX限(xian)制充(chong)(chong)電(dian)(dian)周期用來(lai)保護電(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)過長。將(jiang)TMAX與GND連接起(qi)來(lai)可將(jiang)最(zui)長充(chong)(chong)電(dian)(dian)時(shi)(shi)間設(she)置(zhi)(zhi)為(wei)三小(xiao)時(shi)(shi)。將(jiang)TMAX懸空可將(jiang)最(zui)大充(chong)(chong)電(dian)(dian)時(shi)(shi)間設(she)置(zhi)(zhi)為(wei)4.5小(xiao)時(shi)(shi)。將(jiang)TMAX和VL連接起(qi)來(lai)可將(jiang)最(zui)長充(chong)(chong)電(dian)(dian)時(shi)(shi)間設(she)置(zhi)(zhi)為(wei)6小(xiao)時(shi)(shi)。

　　（5）綜述討論

　　MAX1501和(he)一個(ge)微處理器相(xiang)結合從而(er)決定它有(you)(you)很好(hao)的(de)(de)(de)充電方(fang)案專用的(de)(de)(de)熱(re)調節電路用來限制電路節點(dian)(dian)(dian)溫度(du)，當快速(su)充電或當環境溫度(du)很高的(de)(de)(de)時(shi)(shi)候確(que)保最大充電電流(liu)不會損(sun)壞充電器，在(zai)沒有(you)(you)電池的(de)(de)(de)情況下(xia)MAX1501提供(gong)可調節的(de)(de)(de)輸出(chu)電壓，在(zai)允(yun)許電池充電的(de)(de)(de)情況下(xia)這個(ge)裝置有(you)(you)較高的(de)(de)(de)適應性, 安全時(shi)(shi)間內可以提供(gong)一個(ge)可調整的(de)(de)(de)快速(su)充電電流(liu),頂端關斷電流(liu),.并且有(you)(you)熱(re)量(liang)方(fang)嵌條調整點(dian)(dian)(dian).其(qi)它特點(dian)(dian)(dian)包括(kuo)輸入電量(liang)檢測

并且有(you)輸(shu)入(ru)低的(de)過(guo)壓(ya)(ya)保護和規(gui)定了較(jiao)低的(de)控(kong)制輸(shu)入(ru).MAX1501能(neng)夠接(jie)受(shou)一個4.5V到(dao)13V的(de)電壓(ya)(ya)供電.但是當輸(shu)入(ru)電壓(ya)(ya)超(chao)過(guo)6.5伏時為(wei)了防止過(guo)多的(de)能(neng)量消耗MAX1501充電停止.MAX1501擴(kuo)大了溫度范圍(-40°C to +85°C)并且體積(ji)也減小了.

5　結束語

　　本文介紹了一種采用ＭＡＸ1501 充電控制芯片設計的簡單實用的鋰離子電池充電器，最后對電(dian)路的(de)特(te)性及充電(dian)參數的(de)設置(zhi)進行了分析。