如今的(de)便(bian)攜式電(dian)(dian)(dian)子(zi)備(bei)(bei)(bei)中(zhong)電(dian)(dian)(dian)池(chi)技(ji)術包(bao)括電(dian)(dian)(dian)量(liang)檢測算法(fa)、電(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)算法(fa)與(yu)(yu)電(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)技(ji)術等幾個方(fang)面。眾所周知,充(chong)電(dian)(dian)(dian)式電(dian)(dian)(dian)池(chi)化學反應(ying)有鎳(nie)鎘、鎳(nie)氫、鋰離子(zi)和鋰聚(ju)合物(wu)4種程(cheng)式,作為便(bian)攜式電(dian)(dian)(dian)子(zi)設(she)(she)備(bei)(bei)(bei)來說,雖(sui)然這(zhe)4種電(dian)(dian)(dian)池(chi)程(cheng)式各有特點,但從能量(liang)密(mi)度(du)與(yu)(yu)安全(quan)性角度(du)的(de)發展與(yu)(yu)實踐可知, 鋰離子(zi)電(dian)(dian)(dian)池(chi)和鋰聚(ju)合物(wu)電(dian)(dian)(dian)池(chi)的(de)優勢己成(cheng)為小型長運行(xing)時間的(de)設(she)(she)備(bei)(bei)(bei)的(de)理想之選(xuan)，比如筆記本電(dian)(dian)(dian)腦以及基(ji)于硬盤的(de)PMP等.對便(bian)攜式電(dian)(dian)(dian)子(zi)備(bei)(bei)(bei)工程(cheng)師來說，正確選(xuan)擇(ze)與(yu)(yu)應(ying)用好便(bian)攜式電(dian)(dian)(dian)子(zi)備(bei)(bei)(bei)中(zhong)電(dian)(dian)(dian)池(chi)技(ji)術至關重要,值此本文將對此作研討(tao),并作應(ying)用舉例分析.

1、關(guan)于(yu)細流充電(dian)、快(kuai)速(su)充電(dian)和(he)穩定充電(dian)的電(dian)池充電(dian)算法

根據最終(zhong)應(ying)用(yong)的(de)能量需求，一個(ge)電(dian)(dian)(dian)池(chi)組可(ke)能包含最多4個(ge)鋰(li)離子或(huo)鋰(li)聚合物電(dian)(dian)(dian)池(chi)芯(xin),其配置可(ke)有多種變化，同(tong)時帶(dai)有一個(ge)主(zhu)流的(de)電(dian)(dian)(dian)源適配器：直(zhi)接的(de)適配器、USB接口或(huo)汽(qi)車充(chong)電(dian)(dian)(dian)器。除去電(dian)(dian)(dian)芯(xin)數量、電(dian)(dian)(dian)芯(xin)的(de)配置或(huo)電(dian)(dian)(dian)源適配器類型上的(de)差別，這些(xie)電(dian)(dian)(dian)池(chi)組都有同(tong)樣的(de)充(chong)電(dian)(dian)(dian)特性。因此它們的(de)充(chong)電(dian)(dian)(dian)算法也一樣。鋰(li)離子與鋰(li)聚合物電(dian)(dian)(dian)池(chi)最好的(de)充(chong)電(dian)(dian)(dian)算法可(ke)以分為3個(ge)階段：細流充(chong)電(dian)(dian)(dian)、快(kuai)速充(chong)電(dian)(dian)(dian)和穩定充(chong)電(dian)(dian)(dian)。

*細流充電.用于對深度放電的電芯進行充電。當電芯電壓在低于大約2.8V時，用一個恒定的0.1C的電流為它充電。
*快速充電.電芯電壓超過細流充電的門檻時，提高充電電流進行快速充電。快速充電電流應低于1.0C。
*穩(wen)(wen)定(ding)電(dian)(dian)(dian)壓(ya)。在快速充(chong)(chong)電(dian)(dian)(dian)過程中(zhong)，一(yi)旦電(dian)(dian)(dian)芯電(dian)(dian)(dian)壓(ya)達(da)到4.2V，穩(wen)(wen)定(ding)電(dian)(dian)(dian)壓(ya)階段就開始了。這時(shi)(shi)可通過最(zui)小(xiao)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流或定(ding)時(shi)(shi)器(qi)(qi)或這兩(liang)者的聯合(he)來中(zhong)斷充(chong)(chong)電(dian)(dian)(dian).當最(zui)小(xiao)電(dian)(dian)(dian)流低(di)于大約0.07C時(shi)(shi)，可中(zhong)斷充(chong)(chong)電(dian)(dian)(dian)。定(ding)時(shi)(shi)器(qi)(qi)則要靠(kao)一(yi)個預設(she)的定(ding)時(shi)(shi)器(qi)(qi)來觸發中(zhong)斷。

高級的電池充電器通(tong)常(chang)帶有附加的(de)安全功(gong)能。比如，如果(guo)電芯溫度超出給(gei)定窗口(kou)，通(tong)常(chang)是(shi)(shi)(shi)0℃--45℃，充(chong)電就會暫(zan)停。除去某(mou)些非常(chang)低端的(de)設備，現在(zai)市面(mian)上的(de)鋰離子／鋰聚合物電池充(chong)電方案都集成或是(shi)(shi)(shi)帶有外置的(de)元(yuan)件，以便(bian)按照充(chong)電特(te)性進行充(chong)電，這不光是(shi)(shi)(shi)為了取得更佳充(chong)電效果(guo)，同時也是(shi)(shi)(shi)為了安全。

2、鋰離子/聚合物(wu)電池(chi)充電方案(an)

鋰離子/聚(ju)合(he)物電(dian)池的(de)充電(dian)方(fang)案對于(yu)不(bu)(bu)同數量的(de)電(dian)芯、電(dian)芯配置(zhi)以及電(dian)源類型(xing)還是不(bu)(bu)同的(de)。目前主要有3種(zhong)主要的(de)充電(dian)方(fang)案：線性，Buck(降壓)開關(guan)和SEPIC(升壓與降壓)開關(guan)。

2.1線性方案

當充(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)輸(shu)入電(dian)(dian)(dian)壓(ya)大于全(quan)充(chong)(chong)滿電(dian)(dian)(dian)芯(xin)加上充(chong)(chong)足凈空之(zhi)后的開路電(dian)(dian)(dian)壓(ya)時(shi)，最(zui)好(hao)用線性方(fang)案，特別是(shi)(shi)1.0C快速(su)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)不(bu)比(bi)1A大太多(duo)時(shi)。比(bi)如，MP3播(bo)放(fang)器(qi)(qi)通(tong)常只(zhi)有一個(ge)電(dian)(dian)(dian)芯(xin)，容(rong)量從700到1500mAh不(bu)等，滿充(chong)(chong)開路電(dian)(dian)(dian)壓(ya)是(shi)(shi)4.2V。MP3播(bo)放(fang)機的電(dian)(dian)(dian)源(yuan)通(tong)常是(shi)(shi)AC／DC適配器(qi)(qi)或者是(shi)(shi)USB接口，其輸(shu)出是(shi)(shi)規(gui)則(ze)的5V；這時(shi)，線性方(fang)案的充(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)就是(shi)(shi)最(zui)簡單、最(zui)有效率的方(fang)案。圖2所示為(wei)鋰離子/聚合物電(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)方(fang)案線性方(fang)案,基本結構和線性電(dian)(dian)(dian)壓(ya)規(gui)整器(qi)(qi)一樣(yang)。

*線(xian)(xian)性方(fang)案的(de)(de)充(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)應用(yong)例舉-雙輸入Li+充(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)及智能電(dian)(dian)(dian)源(yuan)選擇器(qi)(qi)MAX8677A。MAX8677A是雙輸入USB/AC適配器(qi)(qi)線(xian)(xian)性充(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)，內置Smart Power Selector，用(yong)于由可充(chong)(chong)(chong)電(dian)(dian)(dian)單(dan)節Li+電(dian)(dian)(dian)池供電(dian)(dian)(dian)的(de)(de)便(bian)攜(xie)式設備(bei)(bei)。該(gai)充(chong)(chong)(chong)電(dian)(dian)(dian)器(qi)(qi)集成(cheng)了電(dian)(dian)(dian)池和外部電(dian)(dian)(dian)源(yuan)充(chong)(chong)(chong)電(dian)(dian)(dian)和切換負載所需的(de)(de)全(quan)部功率開關，因此無需外部 MOSFET。MAX8677A理想用(yong)于便(bian)攜(xie)式設備(bei)(bei)，例如智能手機(ji)、PDA、便(bian)攜(xie)式多媒體播放(fang)器(qi)(qi)、GPS導航設備(bei)(bei)、數碼相機(ji)、以及數碼攝像機(ji)。

MAX8677A可以工作于獨立的USB和AC適配器電源輸入下或兩個輸入中的任意一個輸入下。當連接外部電源時，智能電源選擇器允許系統不連接電池或可以與深度放電電池連接。智能充電器電(dian)(dian)源(yuan)選擇器(qi)自動將電(dian)(dian)池(chi)切換到系統(tong)負載，使用系統(tong)未利用的(de)(de)輸(shu)入(ru)(ru)(ru)電(dian)(dian)源(yuan)部分(fen)為電(dian)(dian)池(chi)充(chong)電(dian)(dian)，充(chong)分(fen)利用有(you)限的(de)(de)USB和(he)適配器(qi)輸(shu)入(ru)(ru)(ru)電(dian)(dian)源(yuan)。所(suo)有(you)需要的(de)(de)電(dian)(dian)流檢(jian)測(ce)電(dian)(dian)路，包(bao)括(kuo)(kuo)集成(cheng)的(de)(de)功率開關，均(jun)集成(cheng)于片上。DC輸(shu)入(ru)(ru)(ru)電(dian)(dian)流限最(zui)高可調(diao)(diao)節(jie)至(zhi)2A，而(er)DC和(he)USB輸(shu)入(ru)(ru)(ru)均(jun)可支(zhi)持100mA、500mA、和(he)USB掛起模式。充(chong)電(dian)(dian)電(dian)(dian)流可調(diao)(diao)節(jie)至(zhi)高達1.5A，從而(er)支(zhi)持 寬范圍的(de)(de)電(dian)(dian)池(chi)容性。MAX8677A的(de)(de)其他特性包(bao)括(kuo)(kuo)熱(re)調(diao)(diao)節(jie)、過壓(ya)保(bao)護、充(chong)電(dian)(dian)狀態和(he)故障(zhang)輸(shu)出、電(dian)(dian)源(yuan)好(hao)監視(shi)、電(dian)(dian)池(chi)熱(re)敏電(dian)(dian)阻監視(shi)、以及充(chong)電(dian)(dian)定(ding)時器(qi)。MAX8677A采用節(jie)省空間的(de)(de)、熱(re)增(zeng)強型、4mm×4mm、24引腳的(de)(de)TQFN封裝，規(gui)定(ding)工(gong)作于擴展(zhan)級(ji)溫度范圍(-40～+85℃)。

2.2 Buck(降壓)開關(guan)方案

當1.0C充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流大(da)于(yu)1A，或(huo)(huo)者(zhe)輸入電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)比電(dian)(dian)(dian)(dian)(dian)(dian)(dian)芯的(de)全充滿開(kai)路電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)高很多時，Buck或(huo)(huo)者(zhe)降(jiang)壓(ya)(ya)(ya)(ya)(ya)方案就是一個更好的(de)選擇。比如，在基(ji)于(yu)硬盤的(de)PMP中，通常使用單芯鋰離(li)子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池，全充滿開(kai)路電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)是4.2V，容量(liang)從1200到(dao)2400mAh不等。而現(xian)在PMP通常是用汽(qi)車套(tao)件來(lai)充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)，它的(de)輸出(chu)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)在9V到(dao)16V之間。在輸入電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)和電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)之間比較高的(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)差(cha)(最小4.8V)會讓線(xian)性方案降(jiang)低效率。這種(zhong)低效率，加(jia)上大(da)于(yu)1.2A的(de)1C快速充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)流，會產生嚴重的(de)散(san)熱(re)問題。為(wei)避免這種(zhong)情況，就要(yao)采用Buck方案。圖3為(wei)鋰電(dian)(dian)(dian)(dian)(dian)(dian)(dian)池充電(dian)(dian)(dian)(dian)(dian)(dian)(dian)器方案示意圖,基(ji)本(ben)結構同(tong)(tong)Buck(降(jiang)壓(ya)(ya)(ya)(ya)(ya))開(kai)關電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)(ya)(ya)調節器完(wan)全相同(tong)(tong)。

2.3 SEPIC(升(sheng)壓與(yu)降壓)開關方案

在某些使用3個甚(shen)至4個鋰離子(zi)／聚合物電(dian)(dian)(dian)芯(xin)串聯的(de)設備中(zhong)，充電(dian)(dian)(dian)器的(de)輸(shu)入(ru)電(dian)(dian)(dian)壓(ya)(ya)就不(bu)總是大于(yu)電(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)壓(ya)(ya)。比如，筆記本電(dian)(dian)(dian)腦使用3芯(xin)鋰離子(zi)電(dian)(dian)(dian)池(chi)組，滿充開(kai)路電(dian)(dian)(dian)壓(ya)(ya)是12．6V(4．2V x3)，容量從1800mAh到3600mAh。輸(shu)入(ru)電(dian)(dian)(dian)源要么是輸(shu)出(chu)(chu)電(dian)(dian)(dian)壓(ya)(ya)1 6V的(de)AC／DC適配器，要么是汽車套件，輸(shu)出(chu)(chu)電(dian)(dian)(dian)壓(ya)(ya)在9V到16V之(zhi)間。很顯然地(di)，線性和Buck方案(an)都不(bu)能為(wei)這組電(dian)(dian)(dian)池(chi)組充電(dian)(dian)(dian)。這就要用上SEPIC方案(an)，它能在輸(shu)出(chu)(chu)電(dian)(dian)(dian)壓(ya)(ya)高于(yu)電(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)壓(ya)(ya)時工(gong)作(zuo)，也能在輸(shu)出(chu)(chu)電(dian)(dian)(dian)壓(ya)(ya)低于(yu)電(dian)(dian)(dian)池(chi)時工(gong)作(zuo)。

3、電量檢測算法

許多可攜式產(chan)品都利(li)用(yong)電(dian)(dian)壓(ya)測量(liang)(liang)值來(lai)估計(ji)電(dian)(dian)池(chi)(chi)剩馀電(dian)(dian)量(liang)(liang)，但是電(dian)(dian)池(chi)(chi)電(dian)(dian)壓(ya)與剩馀電(dian)(dian)量(liang)(liang)的(de)關系卻(que)會隨著放電(dian)(dian)率、溫度和電(dian)(dian)池(chi)(chi)老(lao)化程度而改變，使這種方法(fa)的(de)誤差(cha)率最高可達50％。市(shi)場對使用(yong)時間更長的(de)產(chan)品需(xu)求(qiu)不斷增(zeng)強(qiang)，因此(ci)系統設(she)計(ji)人(ren)員需(xu)要更加(jia)精(jing)確的(de)解決方案。使用(yong)電(dian)(dian)量(liang)(liang)檢測計(ji)吧來(lai)測量(liang)(liang)電(dian)(dian)池(chi)(chi)充(chong)人(ren)或(huo)消(xiao)耗的(de)電(dian)(dian)量(liang)(liang)，將能夠在很(hen)寬的(de)應用(yong)電(dian)(dian)源級(ji)別(bie)范圍內提(ti)供更精(jing)確的(de)電(dian)(dian)池(chi)(chi)電(dian)(dian)量(liang)(liang)估測。

3.1電量檢(jian)測算法應用舉例(li)之一,功能(neng)完整的(de)單＼雙電池(chi)便攜式應用電池(chi)組(zu)設計

*電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)原理(li).較好的(de)電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)計至少要具(ju)(ju)備電(dian)(dian)(dian)池電(dian)(dian)(dian)壓(ya)、電(dian)(dian)(dian)池組溫度和(he)電(dian)(dian)(dian)流、測(ce)(ce)(ce)(ce)量(liang)(liang)(liang)(liang)方法(fa)；一個(ge)微處(chu)(chu)(chu)理(li)9a；和(he)一套及業經驗證(zheng)的(de)電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)算(suan)法(fa)。bq2650x及bq27x00是(shi)功能完(wan)整(zheng)的(de)電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)計，具(ju)(ju)有一個(ge)測(ce)(ce)(ce)(ce)量(liang)(liang)(liang)(liang)電(dian)(dian)(dian)壓(ya)與溫度的(de)模數轉(zhuan)換(huan)器(ADC)和(he)一個(ge)測(ce)(ce)(ce)(ce)量(liang)(liang)(liang)(liang)電(dian)(dian)(dian)流與充電(dian)(dian)(dian)感測(ce)(ce)(ce)(ce)的(de)模數轉(zhuan)換(huan)器。這(zhe)(zhe)些電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)計還具(ju)(ju)有一個(ge)微處(chu)(chu)(chu)理(li)器，負(fu)責執(zhi)行(xing)德州儀(yi)器的(de)電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)算(suan)法(fa)。這(zhe)(zhe)些演算(suan)法(fa)會補償鋰離子電(dian)(dian)(dian)池的(de)自放電(dian)(dian)(dian)、老化、溫度和(he)放電(dian)(dian)(dian)率等因素(su)。晶片(pian)內含(han)微處(chu)(chu)(chu)理(li)器為主機系(xi)統處(chu)(chu)(chu)理(li)器省下(xia)這(zhe)(zhe)些計算(suan)負(fu)擔(dan).電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)計能夠提供(gong)剩(sheng)余電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)狀態等信(xin)(xin)息，bq27x00系(xi)列產品還提供(gong)剩(sheng)余可(ke)運行(xing)時間(Run Time to Empty)主機可(ke)隨時向電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)計查詢這(zhe)(zhe)些信(xin)(xin)息，再透過LED指示燈或(huo)屏幕顯示將電(dian)(dian)(dian)池信(xin)(xin)息通知用戶。電(dian)(dian)(dian)量(liang)(liang)(liang)(liang)檢(jian)(jian)(jian)(jian)測(ce)(ce)(ce)(ce)計的(de)使用非常(chang)方便，系(xi)統處(chu)(chu)(chu)理(li)器僅需要配置(zhi)12C或(huo)HDQ通信(xin)(xin)驅動器即可(ke)。

*電(dian)(dian)(dian)(dian)池(chi)(chi)組電(dian)(dian)(dian)(dian)路(lu)描述.圖4(a)為可(ke)(ke)選(xuan)用(yong)(yong)具有鑒定功(gong)能(neng)IC的典(dian)型的電(dian)(dian)(dian)(dian)池(chi)(chi)組應用(yong)(yong)電(dian)(dian)(dian)(dian)路(lu)。根據所(suo)使用(yong)(yong)電(dian)(dian)(dian)(dian)量(liang)檢(jian)(jian)測計IC的不(bu)同(tong)，電(dian)(dian)(dian)(dian)池(chi)(chi)組至少需要有三到(dao)四個外部終端。VCC及(ji)(ji)BAT引腳會連(lian)到(dao)電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓，以便(bian)為，C供電(dian)(dian)(dian)(dian)及(ji)(ji)測量(liang)電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓。電(dian)(dian)(dian)(dian)池(chi)(chi)接地端連(lian)接了一個電(dian)(dian)(dian)(dian)阻(zu)(zu)值(zhi)較小(xiao)的檢(jian)(jian)測電(dian)(dian)(dian)(dian)阻(zu)(zu)器，讓電(dian)(dian)(dian)(dian)量(liang)檢(jian)(jian)測計的高阻(zu)(zu)抗SRP及(ji)(ji)SRN輸入端能(neng)夠監控感測電(dian)(dian)(dian)(dian)阻(zu)(zu)兩端的電(dian)(dian)(dian)(dian)壓。通(tong)過(guo)流經檢(jian)(jian)測電(dian)(dian)(dian)(dian)阻(zu)(zu)器的電(dian)(dian)(dian)(dian)流可(ke)(ke)用(yong)(yong)來判斷電(dian)(dian)(dian)(dian)池(chi)(chi)充入或釋放的電(dian)(dian)(dian)(dian)量(liang)。設計人員選(xuan)擇檢(jian)(jian)測電(dian)(dian)(dian)(dian)阻(zu)(zu)值(zhi)時必須考慮(lv)電(dian)(dian)(dian)(dian)阻(zu)(zu)兩端的電(dian)(dian)(dian)(dian)壓不(bu)能(neng)超過(guo)100 mV，過(guo)低的電(dian)(dian)(dian)(dian)阻(zu)(zu)值(zhi)可(ke)(ke)能(neng)會在電(dian)(dian)(dian)(dian)流較小(xiao)時產生誤差。電(dian)(dian)(dian)(dian)路(lu)板布局(ju)必須確保從(cong)SRP及(ji)(ji)SRN到(dao)檢(jian)(jian)測電(dian)(dian)(dian)(dian)阻(zu)(zu)器的連(lian)接要盡(jin)可(ke)(ke)能(neng)靠近感測電(dian)(dian)(dian)(dian)阻(zu)(zu)端；換言之，它們應該(gai)是采用(yong)(yong)Kelvin連(lian)線。

HDQ引腳需要外部上拉(la)電(dian)阻器(qi)，該(gai)電(dian)阻應位于主機(ji)或主應用端，這樣電(dian)量(liang)檢測(ce)計(ji)才能在電(dian)池(chi)組與便攜式設備連(lian)接斷開時啟用睡眠功能。建議上拉(la)電(dian)阻值選用10 kΩ。

*電(dian)(dian)池(chi)(chi)組(zu)鑒(jian)定(ding)。價格低廉的(de)(de)偽冒電(dian)(dian)池(chi)(chi)的(de)(de)問題日益嚴重，這(zhe)(zhe)些電(dian)(dian)池(chi)(chi)可能不(bu)包含(han)OEM廠(chang)商(shang)要(yao)求(qiu)的(de)(de)安全保護電(dian)(dian)路。所以，真品電(dian)(dian)池(chi)(chi)組(zu)可包含(han)圖4(a)所示的(de)(de)鑒(jian)定(ding)電(dian)(dian)路。當要(yao)鑒(jian)定(ding)電(dian)(dian)池(chi)(chi)時(shi)，主(zhu)機(ji)向含(han)有IC(bq26150，作用是(shi)循環冗余(yu)校驗(yan)(CRC))的(de)(de)電(dian)(dian)池(chi)(chi)組(zu)發出一(yi)個(ge)(ge)詢問值(challenge)，電(dian)(dian)池(chi)(chi)組(zu)所含(han)的(de)(de)CRC會根據這(zhe)(zhe)個(ge)(ge)詢問值和，IC中內建(jian)的(de)(de)CRC多項(xiang)式計算(suan)(suan)這(zhe)(zhe)個(ge)(ge)CRC值。CRC是(shi)基于(yu)主(zhu)機(ji)的(de)(de)查(cha)詢命令(ling)與(yu)IC中秘(mi)密定(ding)義的(de)(de)CRC多項(xiang)式完成(cheng)的(de)(de)，主(zhu)機(ji)也會進行CRC值計算(suan)(suan)井與(yu)電(dian)(dian)池(chi)(chi)組(zu)的(de)(de)計算(suan)(suan)結果比較(jiao)以確定(ding)鑒(jian)定(ding)是(shi)否(fou)成(cheng)功。一(yi)旦電(dian)(dian)池(chi)(chi)通過(guo)鑒(jian)定(ding)，bq26150則會發出指令(ling)以確保主(zhu)機(ji)與(yu)電(dian)(dian)量檢測計之(zhi)間的(de)(de)資料線路通訊正常。當電(dian)(dian)池(chi)(chi)連(lian)接(jie)中斷或重新連(lian)接(jie)時(shi)，整個(ge)(ge)鑒(jian)定(ding)過(guo)程(cheng)將重復一(yi)次。

3.2電量(liang)檢測(ce)算法應用(yong)舉例(li)之二,能適用(yong)于各種(zhong)通用(yong)電量(liang)計的新型IC.

當今不少制造廠商可提供種類豐富(fu)的電(dian)量計IC,，用(yong)戶可從中(zhong)選取合適的功(gong)能器件，以(yi)優化產品(pin)的性價比。利用(yong)電(dian)量計貯測量的電(dian)池參數，這種分離(li)(li)式(shi)(shi)架構允許用(yong)戶在主機內(nei)定制電(dian)量計量算法．從而(er)省去電(dian)池組內(nei)嵌(qian)處理器的成本。值(zhi)此(ci)以(yi)Dallase semicconductor公(gong)司名為例(li)的DS2762芯(xin)片作典型(xing)(xing)分析. 一新型(xing)(xing)分離(li)(li)式(shi)(shi)電(dian)量計IC,其結構見(jian)圖(tu)5(a)所示.

*DS2762應用特征

DS2762是一(yi)款單節鋰電(dian)(dian)池電(dian)(dian)量(liang)(liang)計與(yu)保護電(dian)(dian)路(lu)，集(ji)成于(yu)(yu)一(yi)片(pian)(pian)微(wei)小(xiao)的(de)(de)2.46mm× 2.74mm倒裝片(pian)(pian)封裝。由(you)于(yu)(yu)內部集(ji)成了(le)用(yong)于(yu)(yu)電(dian)(dian)量(liang)(liang)檢測的(de)(de)高(gao)精(jing)密電(dian)(dian)阻，該款器件非(fei)常節省空間。它所具有(you)的(de)(de)小(xiao)尺寸和無(wu)可(ke)比擬的(de)(de)高(gao)集(ji)成度，對于(yu)(yu)移動(dong)電(dian)(dian)話電(dian)(dian)池組及(ji)其它類似的(de)(de)手(shou)持產品，如PDA等，都非(fei)常理想。集(ji)成的(de)(de)保護電(dian)(dian)路(lu)連續(xu)地(di)監視電(dian)(dian)池的(de)(de)過壓、欠壓和過流(liu)故障(充電(dian)(dian)或放電(dian)(dian)期間)。不同于(yu)(yu)獨立的(de)(de)保護IC，DS2762允(yun)許主處理器監視/控(kong)制保護FET的(de)(de)導(dao)通狀態，這樣，可(ke)以(yi)通過DS2762的(de)(de)保護電(dian)(dian)路(lu)實現(xian)系統(tong)電(dian)(dian)源控(kong)制。DS2762也可(ke)以(yi)充電(dian)(dian)一(yi)個已深度消(xiao)耗(hao)的(de)(de)電(dian)(dian)池，當電(dian)(dian)池電(dian)(dian)壓不足3V時(shi)，提供一(yi)條限制電(dian)(dian)流(liu)的(de)(de)恢(hui)復(fu)充電(dian)(dian)路(lu)徑。

DS2762能夠精(jing)確監視電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)和(he)溫度(du)(du)，其動態范(fan)圍與分辨(bian)率滿足(zu)任何通(tong)(tong)(tong)行(xing)的(de)(de)(de)移動通(tong)(tong)(tong)信產品(pin)的(de)(de)(de)測(ce)(ce)試標準。測(ce)(ce)得(de)的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)對(dui)內(nei)部產生的(de)(de)(de)時(shi)基進行(xing)積分，實現(xian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量計(ji)量。通(tong)(tong)(tong)過實時(shi)、連(lian)續的(de)(de)(de)自動失調糾正，電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量計(ji)量的(de)(de)(de)精(jing)度(du)(du)得(de)以提高。內(nei)置的(de)(de)(de)檢測(ce)(ce)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻消除了(le)因制(zhi)造工(gong)藝(yi)和(he)溫度(du)(du)而造成的(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻變化，進一步提高了(le)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量計(ji)的(de)(de)(de)精(jing)度(du)(du)。重要數據保(bao)存(cun)于(yu)32字(zi)(zi)節(jie)、可加(jia)鎖的(de)(de)(de)EEPROM；16字(zi)(zi)節(jie)的(de)(de)(de)SRAM用(yong)于(yu)保(bao)存(cun)動態數據。與DS2762的(de)(de)(de)所有通(tong)(tong)(tong)信均(jun)通(tong)(tong)(tong)過1-Wire、多(duo)節(jie)點通(tong)(tong)(tong)信接口(kou)進行(xing)，最(zui)大限度(du)(du)減(jian)少(shao)了(le)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)組與主機的(de)(de)(de)連(lian)線(xian)。其主要特征為(wei)；單節(jie)鋰(li)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)保(bao)護器(qi)；高精(jing)度(du)(du)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)量計(ji)量)、電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)和(he)溫度(du)(du)測(ce)(ce)量；可選(xuan)的(de)(de)(de)集(ji)成25mΩ檢測(ce)(ce)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻，每(mei)個(ge)DS2762經過單獨微(wei)調；0V電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)恢(hui)復充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)；32字(zi)(zi)節(jie)可加(jia)鎖EEPROM，16字(zi)(zi)節(jie)SRAM，64位ROM；

1-Wire，多(duo)節點，數(shu)字通(tong)信接口(kou)；支持(chi)多(duo)電(dian)池組電(dian)源(yuan)管(guan)理(li)，并通(tong)過保護(hu)FET實現(xian)系統電(dian)源(yuan)控制；休(xiu)眠模式(shi)下電(dian)源(yuan)電(dian)流僅(jin)2?A(最大);工(gong)作模式(shi)下電(dian)源(yuan)電(dian)流為90?A(最大);2.46mm×2.74mm倒(dao)裝片封裝或(huo)16引(yin)腳下SSOP封裝，兩者均可選擇帶或(huo)不帶檢測電(dian)阻;復具有備有評估板.

4、結論

應用好便攜(xie)式(shi)電子(zi)設備的(de)電池技(ji)術是(shi)選(xuan)擇鋰離子(zi)電池和鋰聚(ju)合物電池及其(qi)充(chong)電器的(de)基(ji)礎.之于如何正確選(xuan)擇,還必須視便攜(xie)式(shi)電子(zi)備的(de)具(ju)體要求而定。