應(ying)用(yong)(yong)比較廣泛快(kuai)速充(chong)電(dian)管理芯片基本上有兩種(zhong)類(lei)型。一種(zhong)是(shi)單片機，另一種(zhong)是(shi)快(kuai)速充(chong)電(dian)管理專用(yong)(yong)集成(cheng)電(dian)路。成(cheng)都國騰微電(dian)子(zi)有限(xian)公司成(cheng)功開發出一款鎳(nie)氫(qing)/鎳(nie)鎘電(dian)池快(kuai)速充(chong)電(dian)智能(neng)管理芯片――GM6801。該芯片外(wai)部管腳控(kong)制功能(neng)可編程(cheng)，無需外(wai)部控(kong)制器支持，使充(chong)電(dian)過程(cheng)檢測(ce)控(kong)制完全自動化，所需外(wai)圍器件(jian)少，應(ying)用(yong)(yong)設計簡單。

GM6801應(ying)用(yong)方案優勢

   GM6801是快速(su)充(chong)電(dian)(dian)(dian)管理(li)(li)專用(yong)集成電(dian)(dian)(dian)路。與單片(pian)機相比，由專用(yong)集成電(dian)(dian)(dian)路實現快速(su)充(chong)電(dian)(dian)(dian)管理(li)(li)優(you)勢主要體(ti)現在幾個方面(mian)：

1. 專(zhuan)用集(ji)(ji)成(cheng)(cheng)電(dian)路在硬件(jian)中集(ji)(ji)成(cheng)(cheng)了對快速(su)充(chong)電(dian)管理(li)全部算(suan)法，無(wu)需開發控制(zhi)軟(ruan)件(jian)，從而有效(xiao)縮短產品設(she)計(ji)周期，簡(jian)化設(she)計(ji)流(liu)程，所(suo)需外圍器件(jian)少，使應(ying)用設(she)計(ji)變得(de)簡(jian)單；

2. 采用單片機實現中高端快速充電器時(shi)，對(dui)單片(pian)(pian)機有較(jiao)(jiao)高(gao)要求，比如需(xu)要較(jiao)(jiao)多I/O口，需(xu)要自帶AD等，還要開(kai)發相關軟件，這(zhe)樣(yang)采用單片(pian)(pian)機所(suo)需(xu)成本往(wang)往(wang)較(jiao)(jiao)高(gao)；

3. 專(zhuan)用集成(cheng)電(dian)路可以實現對(dui)快速充電(dian)過程(cheng)(cheng)精(jing)確控制，比(bi)如GM6801就采(cai)用了(le)帶瞬間放電(dian)過程(cheng)(cheng)脈沖充電(dian)形式(shi)。這樣(yang)可以在快速充電(dian)過程(cheng)(cheng)中及時消除大電(dian)流造成(cheng)電(dian)極化效應，使電(dian)池充電(dian)效果更佳；

4. 由于快速充電器涉及安全(quan)問題，專用集(ji)成電(dian)路(lu)良好一致性和穩定性相對(dui)普(pu)通單片機(ji)來說更(geng)具(ju)優(you)勢。

   此外，GM6801本身(shen)采用(yong)一些個性化設計：GM6801內置10位(wei)AD轉(zhuan)換器，可以實時(shi)采集每節電(dian)(dian)池(chi)(chi)電(dian)(dian)壓和溫度信息(xi)，自帶(dai)“Condition fit”功(gong)能(neng)能(neng)夠避(bi)免環境變(bian)化帶(dai)來(lai)干擾，保證(zheng)對(dui)快速充(chong)電(dian)(dian)/放電(dian)(dian)過程檢測(ce)判斷(duan)準確(que)(que)可靠。GM6801對(dui)每節電(dian)(dian)池(chi)(chi)充(chong)電(dian)(dian)/放電(dian)(dian)過程檢測(ce)判斷(duan)方(fang)法有電(dian)(dian)壓負增長(chang)(-ΔV)、最(zui)大(da)電(dian)(dian)壓、最(zui)大(da)充(chong)電(dian)(dian)時(shi)間、最(zui)高溫度四種方(fang)式，通過多參(can)數(shu)評(ping)估來(lai)進行綜(zong)合(he)判斷(duan)，以確(que)(que)保電(dian)(dian)池(chi)(chi)被最(zui)大(da)化充(chong)滿，同時(shi)避(bi)免過充(chong)，從而延(yan)長(chang)電(dian)(dian)池(chi)(chi)使用(yong)壽(shou)命(ming)。

   GM6801自(zi)動判斷電池(chi)(chi)有效性、自(zi)動識別(bie)電池(chi)(chi)種(zhong)類，具(ju)備超溫保(bao)護(hu)和(he)最(zui)大充電時(shi)間保(bao)護(hu)，保(bao)證了充電過程安全性。更(geng)完善(shan)功能包括：可(ke)直接驅(qu)動4個(ge)雙色LED顯(xian)示(shi)(shi)各個(ge)電池(chi)(chi)狀態；可(ke)對充電/放(fang)電狀態進行聲音提示(shi)(shi)；在高溫情況(kuang)下可(ke)以自(zi)動啟動風扇(shan)；具(ju)備充電/放(fang)電狀態數據輸出功能，可(ke)直觀顯(xian)示(shi)(shi)各個(ge)電池(chi)(chi)電量。

GM6801解決方案設計(ji)

   GM6801應用(yong)方案如(ru)圖1所示，設(she)計第一(yi)步需要確定智能(neng)快(kuai)速(su)充電(dian)(dian)器電(dian)(dian)源電(dian)(dian)流(liu)。根(gen)據充電(dian)(dian)電(dian)(dian)池容量以(yi)及(ji)想要達(da)到充電(dian)(dian)速(su)度，可(ke)以(yi)計算出快(kuai)速(su)充電(dian)(dian)器電(dian)(dian)源電(dian)(dian)流(liu)值。

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圖1：GM6801應用方案示意圖

   例如，設計一個針對2,000mAh充電電池充電器，若需要把充滿兩節電池最大時間控制在90分鐘以內，那么根據GM6801數據手冊中相關參數可以確定充電時間為1C，由此確定平均充電電流I_C=2,000mA。放電電流I_dischg由放電回路電阻值確定，假定放電電流I_DISCHG≈1,000mA，再根據GM6801數據手(shou)冊中(zhong)計算(suan)公(gong)式可以推算(suan)出充電(dian)器(qi)電(dian)源實際電(dian)流值為：

I_CHG＝(I_C I_DISCHG/32)×(64/31)＝(2,000mA 1,000mA/32)×(64/31)≈4,200mA。

   即(ji)設計(ji)充電器(qi)(qi)時，充電器(qi)(qi)電源電流(liu)值應該設計(ji)成等于(yu)或略大于(yu)4,200mA。另(ling)外(wai)需要(yao)強調是，選擇熱敏電阻非常重要(yao)。

   熱(re)(re)(re)敏電(dian)阻(zu)是GM6801應用(yong)系統中(zhong)采集溫(wen)(wen)度(du)關鍵元件。在GM6801應用(yong)電(dian)路(lu)中(zhong)，熱(re)(re)(re)敏電(dian)阻(zu)必須直(zhi)接(jie)或(huo)通過導熱(re)(re)(re)材料與被測電(dian)池緊密接(jie)觸。熱(re)(re)(re)敏電(dian)阻(zu)B值(zhi)=3,300K，熱(re)(re)(re)敏電(dian)阻(zu)電(dian)阻(zu)值(zhi)根據應用(yong)電(dian)路(lu)確定，按照GM6801數據手冊中(zhong)提供應用(yong)電(dian)路(lu)(如圖2所示)，熱(re)(re)(re)敏電(dian)阻(zu)(RT)與一個(ge)電(dian)阻(zu)(R)串聯，電(dian)阻(zu)另(ling)一端連(lian)接(jie) 5V電(dian)源(yuan)(Vi)，熱(re)(re)(re)敏電(dian)阻(zu)另(ling)一端接(jie)地，熱(re)(re)(re)敏電(dian)阻(zu)與電(dian)阻(zu)連(lian)接(jie)點引出反應溫(wen)(wen)度(du)變(bian)化電(dian)壓采樣信息(Vt)。

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圖2：GM6801應用方案中熱敏電阻應用電路示意圖

   要求在不同溫(wen)度(du)(du)點(dian)采(cai)(cai)集到電壓Vt值(zhi)(zhi)與GM6801數據手(shou)冊中提供數據基本(ben)一致(zhi)，這(zhe)樣才能(neng)保證由(you)該熱敏電阻網絡采(cai)(cai)集到電池溫(wen)度(du)(du)信(xin)息(xi)與設計中溫(wen)度(du)(du)刻度(du)(du)一致(zhi)。推薦(jian)RT和(he)R標(biao)稱值(zhi)(zhi)都(dou)采(cai)(cai)用27kΩ(25℃時(shi))。

   接下來，需要完成(cheng)一些控(kong)制引腳(jiao)和輸(shu)入(ru)輸(shu)出引腳(jiao)設定。

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圖3：GM6801控制部分應用電路圖

   如圖3所示，在GM6801應用電路中，鎳氫/鎳鎘電池選擇引腳(NH/ND)與一個外部開關連接，通過開關選擇該引腳接高電平或低電平來決定充電電池類型，低電平為鎳氫，高電平為鎳鎘，當該引腳狀態改變時，同時具有復位功能；充電/放電選擇引腳(CHG/DISCHG)與一個外部開關連接，通過開關選擇該引腳接高電平或低電平來決定充電或放電，低電平為充電，高電平為放電；充電時間選擇引腳(CHGTIME0/CHGTIME1)分別與外部電路連接，通過設定該引腳接高電平或低電平，由CHGTIME0/CHGTIME1兩個引腳狀態決定充電時間(即C值)。 
  

   GM6801系(xi)列QFP44封(feng)裝芯(xin)片采用(yong)四(si)路(lu)充(chong)電(dian)/放(fang)電(dian)回路(lu)獨立控(kong)制，可對最多4節(jie)不同型號(hao)、容量(liang)接(jie)近鎳氫/鎳鎘(ge)電(dian)池任意組合(he)進行并聯(lian)充(chong)電(dian)/放(fang)電(dian)管理(li)。如圖4所(suo)示，在應(ying)用(yong)于(yu)四(si)路(lu)并聯(lian)充(chong)電(dian)/放(fang)電(dian)控(kong)制方式時(shi)，GM6801VCC和(he)Vref通常接(jie) 5V，其中Vref要(yao)求加(jia)10uF旁路(lu)電(dian)容增(zeng)加(jia)穩(wen)定性。工作(zuo)時(shi)鐘(zhong)選用(yong)32.768kHz無源(yuan)晶振。

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圖4：GM6801應用于四路并聯充電/放電管理方案輸入輸出部分電路圖

   GM6801分別(bie)(bie)提供充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)控(kong)制(zhi)(zhi)輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)、放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)控(kong)制(zhi)(zhi)輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)、電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)采(cai)(cai)集輸(shu)(shu)(shu)入、風扇驅(qu)(qu)動(dong)(dong)輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)、蜂(feng)鳴(ming)器輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)、雙色(se)(se)(se)LED控(kong)制(zhi)(zhi)輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)以及串(chuan)行數據輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)，這(zhe)些(xie)功(gong)能(neng)管腳(jiao)(jiao)定(ding)義和功(gong)能(neng)分別(bie)(bie)為：充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)控(kong)制(zhi)(zhi)輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)(CHGCTRL1~4)高電(dian)(dian)(dian)(dian)(dian)(dian)平(ping)(ping)有效，控(kong)制(zhi)(zhi)對應(ying)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)回路(lu)開(kai)關打開(kai)或關閉；放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)控(kong)制(zhi)(zhi)輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)(DISCHG1~4)低電(dian)(dian)(dian)(dian)(dian)(dian)平(ping)(ping)有效，控(kong)制(zhi)(zhi)對應(ying)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)回路(lu)開(kai)關打開(kai)或關閉；電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)采(cai)(cai)集輸(shu)(shu)(shu)入口(CELVOLT1~4)分別(bie)(bie)與(yu)(yu)(yu)四(si)(si)路(lu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)回路(lu)中(zhong)(zhong)(zhong)一個電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)正極(ji)(ji)(ji)(ji)相(xiang)(xiang)連(lian)，用(yong)(yong)于(yu)采(cai)(cai)集每節電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)值；電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)溫度(du)(du)采(cai)(cai)集輸(shu)(shu)(shu)入口(CELTMP1~4)分別(bie)(bie)與(yu)(yu)(yu)四(si)(si)個溫度(du)(du)傳感器中(zhong)(zhong)(zhong)一個相(xiang)(xiang)連(lian)，采(cai)(cai)集相(xiang)(xiang)應(ying)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)溫度(du)(du)信息；風扇驅(qu)(qu)動(dong)(dong)輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)(FANDRV)高電(dian)(dian)(dian)(dian)(dian)(dian)平(ping)(ping)有效，與(yu)(yu)(yu)風扇正輸(shu)(shu)(shu)入腳(jiao)(jiao)相(xiang)(xiang)連(lian)，在(zai)一定(ding)條件(jian)下(xia)可(ke)直接驅(qu)(qu)動(dong)(dong)風扇；蜂(feng)鳴(ming)器輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)(BUZZER)高電(dian)(dian)(dian)(dian)(dian)(dian)平(ping)(ping)有效，與(yu)(yu)(yu)蜂(feng)鳴(ming)器正輸(shu)(shu)(shu)入腳(jiao)(jiao)相(xiang)(xiang)連(lian)，在(zai)一定(ding)條件(jian)下(xia)可(ke)直接驅(qu)(qu)動(dong)(dong)蜂(feng)鳴(ming)器；顯(xian)示電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)/放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)狀態雙色(se)(se)(se)LED控(kong)制(zhi)(zhi)輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)(LED1A/LED1B~LED4A/LED4B)低電(dian)(dian)(dian)(dian)(dian)(dian)平(ping)(ping)有效，其中(zhong)(zhong)(zhong)LED1A~4A分別(bie)(bie)與(yu)(yu)(yu)四(si)(si)個雙色(se)(se)(se)LED紅色(se)(se)(se)極(ji)(ji)(ji)(ji)陰極(ji)(ji)(ji)(ji)相(xiang)(xiang)連(lian)，LED1B~4B分別(bie)(bie)與(yu)(yu)(yu)四(si)(si)個雙色(se)(se)(se)LED綠(lv)色(se)(se)(se)極(ji)(ji)(ji)(ji)陰極(ji)(ji)(ji)(ji)相(xiang)(xiang)連(lian)，這(zhe)四(si)(si)個雙色(se)(se)(se)LED采(cai)(cai)用(yong)(yong)共陽極(ji)(ji)(ji)(ji)方式；串(chuan)行數據輸(shu)(shu)(shu)出(chu)(chu)(chu)(chu)引腳(jiao)(jiao)(SERIES_OUT)以串(chuan)行數據方式實(shi)時送出(chu)(chu)(chu)(chu)電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)量信息，用(yong)(yong)于(yu)直觀顯(xian)示電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)量。

   GM6801系列QFP44封(feng)裝芯片也可以對串聯電(dian)(dian)(dian)池(chi)組(zu)進行充(chong)電(dian)(dian)(dian)/放電(dian)(dian)(dian)管(guan)理。在(zai)針對串聯電(dian)(dian)(dian)池(chi)組(zu)進行充(chong)電(dian)(dian)(dian)/放電(dian)(dian)(dian)控(kong)制時，只需(xu)要(yao)GM6801其中一路(lu)(lu)充(chong)電(dian)(dian)(dian)/放電(dian)(dian)(dian)控(kong)制回路(lu)(lu)即可實(shi)現。

   例如：設(she)定對一(yi)個(ge)四節電(dian)池(chi)串聯電(dian)池(chi)組進行充電(dian)/放電(dian)，采用(yong)GM6801第一(yi)個(ge)控制回路進行充電(dian)/放電(dian)管理。

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圖5：GM6801應用于串聯電池組充電/放電管理方案輸入輸出部分電路圖

   應用(yong)方案如圖5所示，在針對串(chuan)聯電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)組(zu)(zu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)/放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)管理方案中，GM6801控制引(yin)腳和輸(shu)(shu)入輸(shu)(shu)出引(yin)腳設定與并聯充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)/放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)管理不(bu)同之(zhi)處為：電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)采(cai)集(ji)輸(shu)(shu)入口(kou)(這里取CELVOLT1)通(tong)過(guo)(guo)一(yi)個分壓(ya)(ya)電(dian)(dian)(dian)(dian)(dian)(dian)路與串(chuan)聯電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)組(zu)(zu)正極相連，串(chuan)聯電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)組(zu)(zu)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)值(zhi)經(jing)過(guo)(guo)分壓(ya)(ya)電(dian)(dian)(dian)(dian)(dian)(dian)路把(ba)相當于一(yi)節電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)值(zhi)送到電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)采(cai)集(ji)輸(shu)(shu)入口(kou)(CELVOLT1)；原(yuan)來(lai)為了實現自(zi)動判斷充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)/放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)回路是否有電(dian)(dian)(dian)(dian)(dian)(dian)池(chi)而(er)在電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)采(cai)集(ji)輸(shu)(shu)入口(kou)(CELVOLT1)之(zhi)前加 5V上(shang)拉(la)電(dian)(dian)(dian)(dian)(dian)(dian)路不(bu)再(zai)適用(yong)，去掉該上(shang)拉(la)電(dian)(dian)(dian)(dian)(dian)(dian)路后，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)/放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)開(kai)始由芯片(pian)(pian)使(shi)能開(kai)關(guan)控制，當芯片(pian)(pian)使(shi)能開(kai)關(guan)接(jie)通(tong)地電(dian)(dian)(dian)(dian)(dian)(dian)位(GND)時(shi)，開(kai)始充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)/放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)/放(fang)(fang)電(dian)(dian)(dian)(dian)(dian)(dian)過(guo)(guo)程管理及控制由GM6801自(zi)動完成。當芯片(pian)(pian)使(shi)能開(kai)關(guan)接(jie)通(tong) 5V時(shi)，芯片(pian)(pian)停止(zhi)工作。