鑒于市場上鎳鎘電池和鋰電池共存的局面，本文設計的充電器可(ke)以(yi)對這兩種電(dian)池(chi)(chi)(chi)進行充(chong)(chong)電(dian)，對鎳鎘(ge)電(dian)池(chi)(chi)(chi)組(zu)采(cai)用脈沖(chong)充(chong)(chong)電(dian)方式(shi)，對鋰電(dian)池(chi)(chi)(chi)組(zu)采(cai)用恒(heng)流充(chong)(chong)電(dian)方式(shi)，這是(shi)依(yi)據電(dian)池(chi)(chi)(chi)的(de)不(bu)同機理而設(she)計的(de)，真(zhen)正做(zuo)到(dao)了一機兩用，此為該充(chong)(chong)電(dian)器(qi)的(de)創新點，也(ye)是(shi)設(she)計的(de)難點。充(chong)(chong)電(dian)器(qi)的(de)寬屏LCD可(ke)以(yi)同時顯(xian)示(shi)4組(zu)充(chong)(chong)電(dian)器(qi)的(de)充(chong)(chong)電(dian)狀態，也(ye)可(ke)單獨顯(xian)示(shi)一組(zu)充(chong)(chong)電(dian)器(qi)上電(dian)池(chi)(chi)(chi)的(de)各(ge)項參數，做(zuo)到(dao)了對電(dian)池(chi)(chi)(chi)充(chong)(chong)電(dian)過程的(de)實時監測(ce)。

　　系統整體設計

　　系(xi)統設計目(mu)標是(shi)：

　　1．可(ke)同(tong)時(shi)對4組8.4V的(de)鋰離子電池(chi)或9.2V的(de)鎳(nie)鎘電池(chi)進行(xing)充放電。

　　2．可與電池組中的芯片(pian)通信(xin)，判(pan)斷電池的化學性質。

　　3．對于不同(tong)化(hua)學(xue)性質的(de)電池，將(jiang)采用(yong)相應的(de)充電方式。

　　4．可與電池(chi)(chi)組中(zhong)的(de)芯片通信，得(de)到(dao)該電池(chi)(chi)組的(de)電壓、充電電流、容量等參(can)數(shu)。

　　5．充電器帶有(you)LCD，可顯示(shi)電池的各項數據。

　　該充電器的(de)功能框圖如圖1所示。

　　
       系(xi)統硬件設(she)計

　　總控(kong)單(dan)元的設計(ji)與(yu)實現

　　總控單元是由(you)微控制器PIC16F873和鍵盤(pan)控制芯(xin)片ZLG7289A構(gou)成(cheng)的。主要任務(wu)是負責(ze)與各

個(ge)充(chong)(chong)電單(dan)元(yuan)通信(xin)，并處理用(yong)戶輸(shu)入與LCD顯示信(xin)息。鍵(jian)盤控(kong)(kong)(kong)制(zhi)芯(xin)片在(zai)這里負責6個(ge)按(an)鍵(jian)和12個(ge)LED的(de)控(kong)(kong)(kong)制(zhi)。ZLG7289A與微控(kong)(kong)(kong)制(zhi)器之間(jian)通過SPI總線進行雙向通信(xin)。主(zhu)控(kong)(kong)(kong)單(dan)元(yuan)每秒(miao)查詢一次各個(ge)充(chong)(chong)電單(dan)元(yuan)，獲取(qu)當前充(chong)(chong)電單(dan)元(yuan)的(de)信(xin)息，如有無電池(chi)、電池(chi)性質、電池(chi)電壓等。之后由(you)LCD模塊(kuai)向用(yong)戶顯示。

　　充電單元的設計與實現

　　LTC4002鋰離子(zi)電池充電控制(zhi)芯片

　　LTC4002是一款(kuan)高效獨(du)立開關模式鋰離(li)子電(dian)(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian)(dian)控(kong)制器。該控(kong)制器有4.2V和8.4V兩個版本。LTC4002-8.4具有500kHz開關頻率，是高效電(dian)(dian)(dian)(dian)流模式的(de)PWM控(kong)制器。通過驅動一個外部P溝道MOSFET，它可(ke)以提供4A的(de)充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流，而效率可(ke)高達90％。輸(shu)出(chu)電(dian)(dian)(dian)(dian)壓設置為(wei)8.4V，最終浮動電(dian)(dian)(dian)(dian)壓并具1％的(de)精度(du)，而充電(dian)(dian)(dian)(dian)準確(que)度(du)為(wei)5％。此外，該器件(jian)可(ke)在9V～22V范圍內的(de)多(duo)種墻上(shang)適(shi)配器上(shang)運行。與(yu)遲滯拓撲結構充電(dian)(dian)(dian)(dian)器相比，LTC4002-8.4的(de)快速運行頻率與(yu)電(dian)(dian)(dian)(dian)流模式架(jia)構使(shi)之能夠使(shi)用(yong)小(xiao)型電(dian)(dian)(dian)(dian)感(gan)器和電(dian)(dian)(dian)(dian)容器。

　　鋰離子／鎳鎘電池兩用充電單元(yuan)的總體設計

　　從(cong)前面對(dui)(dui)(dui)LTC4002的(de)分(fen)(fen)析可知，該芯片是(shi)針(zhen)對(dui)(dui)(dui)鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)的(de)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)控制器(qi)，要(yao)實現(xian)對(dui)(dui)(dui)鎳(nie)(nie)鎘(ge)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)需要(yao)解(jie)決以(yi)(yi)下問(wen)題(ti)：首先，LTC4002對(dui)(dui)(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)進行監測，保證(zheng)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)不(bu)超過8.4V。但對(dui)(dui)(dui)于鎳(nie)(nie)鎘(ge)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)組(zu)，充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)截止(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)可以(yi)(yi)達到9.2V。其次，鎳(nie)(nie)鎘(ge)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)即(ji)將結束時，需要(yao)對(dui)(dui)(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)進行以(yi)(yi)正常電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流30％和10％的(de)涓流充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。所(suo)以(yi)(yi)，第二個需要(yao)解(jie)決的(de)問(wen)題(ti)是(shi)如何控制恒流充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流大小。此外，對(dui)(dui)(dui)鎳(nie)(nie)鎘(ge)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)應使(shi)用(yong)脈沖充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)方式。即(ji)以(yi)(yi)1s為周期，95％的(de)時間(jian)用(yong)來充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，1％的(de)時間(jian)用(yong)來放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，其余時間(jian)不(bu)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)也不(bu)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。最后，如何判斷某一個電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)是(shi)鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)還是(shi)鎳(nie)(nie)鎘(ge)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)，因為若把鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)誤判為鎳(nie)(nie)鎘(ge)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)，會使(shi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)高于8.4V，這對(dui)(dui)(dui)鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)是(shi)十分(fen)(fen)危險的(de)，而(er)將鎳(nie)(nie)鎘(ge)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)誤判為鋰離子電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)，則可能造成電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)不(bu)足。因此，必須保證(zheng)極低的(de)誤判率。

　　本部分根據LTC4002的(de)工(gong)作原(yuan)理(li)，設(she)計了(le)既可以對鋰離子電(dian)(dian)(dian)池(chi)進行恒流-恒壓充(chong)(chong)電(dian)(dian)(dian)，又可以對鎳鎘電(dian)(dian)(dian)池(chi)進行脈沖式(shi)充(chong)(chong)電(dian)(dian)(dian)的(de)電(dian)(dian)(dian)路(lu)。充(chong)(chong)電(dian)(dian)(dian)單(dan)元(yuan)的(de)總體功能框圖(tu)如圖(tu)2所示。其中，信號調理(li)電(dian)(dian)(dian)路(lu)使(shi)充(chong)(chong)電(dian)(dian)(dian)器既可以對8.4V的(de)鋰電(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)，又可以對9.2V的(de)鎳鎘電(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)，同時也起到控制充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流大小(xiao)的(de)作用(yong)。

　　利用(yong)微控(kong)制器控(kong)制LTC4002的(de)工作狀態，配(pei)合放(fang)電電路(lu)使(shi)充(chong)電器可以對鎳鎘(ge)電池進行脈沖方式充(chong)電。

　　微控制器通過(guo)一定(ding)的通信(xin)協議(yi)(HDQ16)與智能電池通信(xin)，確定(ding)其容量、化學性質(zhi)等(deng)關鍵參數(shu)。

　　信號調理電路的設計

　　為(wei)了使LTC4002可對(dui)高于(yu)8.4V的電(dian)池進行(xing)恒(heng)流(liu)充電(dian)，并可調節(jie)充電(dian)電(dian)流(liu)，在(zai)LTC4002的BAT和(he)SENSE端與采(cai)樣電(dian)阻(zu)之間(jian)加入一級信(xin)號調理電(dian)路。該(gai)電(dian)路的主要功能是對(dui)采(cai)樣電(dian)阻(zu)兩端的信(xin)號進行(xing)運算，針對(dui)不(bu)同化學性(xing)質的電(dian)池，將相應的信(xin)號送給LTC4002。該(gai)信(xin)號調理電(dian)路如圖3所示(shi)。

這里定義(yi)采(cai)樣電(dian)(dian)(dian)(dian)(dian)阻(zu)兩(liang)(liang)端(duan)的(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)值是VBAT和Vsense，那(nei)么(me)(me)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)在采(cai)樣電(dian)(dian)(dian)(dian)(dian)阻(zu)上的(de)壓(ya)(ya)(ya)降VRS為(wei)：VRS=Vsense-VBAT，該(gai)信號為(wei)減法(fa)器(qi)的(de)輸(shu)出。設乘法(fa)器(qi)的(de)乘系數為(wei)K，那(nei)么(me)(me)乘法(fa)器(qi)的(de)輸(shu)出為(wei)KVRS。對于鋰子電(dian)(dian)(dian)(dian)(dian)池，二(er)選(xuan)一開(kai)關(guan)將(jiang)選(xuan)通電(dian)(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)VBAT；對于鎳鎘電(dian)(dian)(dian)(dian)(dian)池，二(er)選(xuan)一開(kai)關(guan)將(jiang)選(xuan)通7V恒定電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)。這里設二(er)選(xuan)一模擬開(kai)關(guan)的(de)輸(shu)出為(wei)V1，那(nei)么(me)(me)加法(fa)器(qi)的(de)輸(shu)出Vs應為(wei)：Vs=KVRS+V1，這樣一來，送到LTC4002的(de)BAT和SENSE兩(liang)(liang)端(duan)的(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)之差應為(wei)KVRS。只要正確控制K值，就可(ke)(ke)以使充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)為(wei)正常充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)的(de)1／K。因此，可(ke)(ke)以通過(guo)二(er)選(xuan)一開(kai)關(guan)控制電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)為(wei)恒流(liu)(liu)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)時(shi)的(de)10％或30％。

　　對于LTC4002的(de)BAT端輸入值，當開關選通鋰離子電(dian)(dian)池時，BAT的(de)輸入即是電(dian)(dian)池電(dian)(dian)壓。此時，LTC4002可以控制整個鋰離子的(de)充電(dian)(dian)過程。不需任何外界的(de)干預。

　　當(dang)開關選通了7V恒定(ding)電(dian)(dian)(dian)(dian)(dian)壓(ya)后，BAT端的輸入恒定(ding)為(wei)(wei)7V，此時，LTC4002無法知道(dao)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的真實電(dian)(dian)(dian)(dian)(dian)壓(ya)，只認為(wei)(wei)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)壓(ya)為(wei)(wei)7V。所以(yi)，盡管電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)壓(ya)高于8.4V，仍會(hui)以(yi)恒定(ding)電(dian)(dian)(dian)(dian)(dian)流對電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)進行(xing)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)。在(zai)這種情(qing)況下，需要微控(kong)制器的干預，否(fou)則，會(hui)造成電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)的過充(chong)(chong)。由于微控(kong)制器內部帶有(you)ADC，可以(yi)監測電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)壓(ya)的變化。當(dang)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)壓(ya)達到指定(ding)值(zhi)時，減小充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流，直至電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)充(chong)(chong)滿(man)。這樣(yang)就可以(yi)對9.2V的鎳鎘電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)進行(xing)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)了。

　　脈沖充(chong)放電(dian)電(dian)路的設計

　　由于LTC4002是恒流充(chong)電(dian)控(kong)制芯片，因(yin)此，必須(xu)使用微控(kong)制器控(kong)制其充(chong)電(dian)使能引(yin)(yin)腳(jiao)(jiao)COMP。當需(xu)要LTC4002輸(shu)(shu)出(chu)(chu)充(chong)電(dian)脈沖時(shi)，使控(kong)制COMP引(yin)(yin)腳(jiao)(jiao)的端口變為高阻(zu)態，使COMP引(yin)(yin)腳(jiao)(jiao)自行(xing)升(sheng)至360mV以上時(shi)，便有充(chong)電(dian)電(dian)流輸(shu)(shu)出(chu)(chu)。放(fang)電(dian)時(shi)，必須(xu)將COMP引(yin)(yin)腳(jiao)(jiao)拉低(di)，使LTC4002關斷充(chong)電(dian)電(dian)流。之后，再打開放(fang)電(dian)電(dian)路。微控(kong)制器選用PIC16F873，它是一款基于Fla

sh的8位(wei)微控制器。內部(bu)有定時器、看門狗電路、10位(wei)ADC等模塊。

　　微(wei)控制器以(yi)1s為(wei)周(zhou)期對鎳(nie)鎘電池進行脈沖充放電。

　　系統軟件設計

　　系統軟(ruan)件總體設(she)計

　　充電(dian)(dian)單(dan)(dan)元中的(de)微控制器主要負責(ze)充電(dian)(dian)過(guo)程的(de)控制和與總控板的(de)通信，程序(xu)流(liu)程如圖4所示(shi)。充電(dian)(dian)單(dan)(dan)元首先判(pan)斷(duan)是(shi)否(fou)有(you)電(dian)(dian)池(chi)，如果有(you)電(dian)(dian)池(chi)放入，則判(pan)斷(duan)充放電(dian)(dian)狀態(tai)(tai)，默(mo)認是(shi)充電(dian)(dian)狀態(tai)(tai)，該狀態(tai)(tai)可由總控單(dan)(dan)元改變。若充電(dian)(dian)單(dan)(dan)元處于(yu)(yu)充電(dian)(dian)狀態(tai)(tai)，則繼續判(pan)斷(duan)電(dian)(dian)池(chi)的(de)化學性質，針對不同(tong)的(de)電(dian)(dian)池(chi)采用不同(tong)的(de)充電(dian)(dian)方(fang)式。若處于(yu)(yu)放電(dian)(dian)狀態(tai)(tai)，則對電(dian)(dian)池(chi)組(zu)進(jin)行放電(dian)(dian)，直到電(dian)(dian)池(chi)電(dian)(dian)壓(ya)低于(yu)(yu)閾值電(dian)(dian)壓(ya)后，轉為充電(dian)(dian)狀態(tai)(tai)。

　　除主程(cheng)序外，總(zong)控單元(yuan)(yuan)與充(chong)電(dian)(dian)單元(yuan)(yuan)的通信是在中(zhong)斷(duan)服(fu)務程(cheng)序中(zhong)實(shi)現的。當(dang)充(chong)電(dian)(dian)單元(yuan)(yuan)收(shou)到總(zong)控單元(yuan)(yuan)的指(zhi)令(ling)(ling)后，進入中(zhong)斷(duan)。若指(zhi)令(ling)(ling)是查詢數據(ju)(ju)指(zhi)令(ling)(ling)，則(ze)(ze)向總(zong)控單元(yuan)(yuan)發送需(xu)要的數據(ju)(ju)。若是充(chong)電(dian)(dian)狀(zhuang)態(tai)(tai)設置指(zhi)令(ling)(ling)，則(ze)(ze)依據(ju)(ju)指(zhi)令(ling)(ling)設置充(chong)電(dian)(dian)單元(yuan)(yuan)的充(chong)電(dian)(dian)狀(zhuang)態(tai)(tai)。

　　通信協議的實現

　　通過與電池組中電能計量芯片通信的方法來判斷電池的性質。本系統可以與遵循HDQ16接口協議的智能電池組進行通信，除了電池組的化學性質外，還可以將電池組的容量、電壓、充電電流、編號等數據一并讀取，供充電器顯示之用。

　　充電單(dan)元可以通過HDQ總線對智(zhi)能電池進行讀(du)(du)操(cao)作。HDQ16接口(kou)協(xie)議(yi)是基于(yu)指(zhi)(zhi)令(ling)(ling)的(de)協(xie)議(yi)。一(yi)(yi)個(ge)處理器發(fa)送8位(wei)(wei)指(zhi)(zhi)令(ling)(ling)碼(ma)給(gei)智(zhi)能電池，這(zhe)個(ge)8位(wei)(wei)的(de)指(zhi)(zhi)令(ling)(ling)碼(ma)由兩部分組成(cheng)，7位(wei)(wei)HDQ16指(zhi)(zhi)令(ling)(ling)碼(ma)(位(wei)(wei)0～6)和1位(wei)(wei)讀(du)(du)／寫(xie)指(zhi)(zhi)令(ling)(ling)。讀(du)(du)／寫(xie)指(zhi)(zhi)令(ling)(ling)指(zhi)(zhi)示(shi)智(zhi)能 電池存(cun)儲接下來(lai)的(de)16位(wei)(wei)數據到(dao)一(yi)(yi)個(ge)指(zhi)(zhi)定的(de)寄(ji)存(cun)器，或者從指(zhi)(zhi)定的(de)寄(ji)存(cun)器輸(shu)出16位(wei)(wei)數據。在HDQ16里，數據字(zi)節(指(zhi)(zhi)令(ling)(ling))或者字(zi)(數據)的(de)最不重要的(de)位(wei)(wei)會優先(xian)傳(chuan)輸(shu)。

　　一個塊(kuai)的(de)(de)傳輸包(bao)括三(san)個不同的(de)(de)部(bu)分(fen)(fen)。第一部(bu)分(fen)(fen)經由主(zhu)機或者(zhe)智能(neng)電(dian)(dian)池(chi)把HDQ16引腳置邏輯低狀態一個tSTRH：B時(shi)間(jian)(jian)后開始(shi)(shi)發送。接下來的(de)(de)部(bu)分(fen)(fen)是(shi)真正的(de)(de)數(shu)(shu)據(ju)傳輸，數(shu)(shu)據(ju)位(wei)在tDSU:B時(shi)間(jian)(jian)間(jian)(jian)隔里是(shi)有效的(de)(de)，負邊界用(yong)來開始(shi)(shi)通信。數(shu)(shu)據(ju)位(wei)被保持一個tDH:DV時(shi)間(jian)(jian)間(jian)(jian)隔，以便允許主(zhu)機或智能(neng)電(dian)(dian)池(chi)采樣數(shu)(shu)據(ju)位(wei)。

　　在負邊界開始通信后(hou)，最后(hou)一(yi)部(bu)分通過返(fan)回給HDQ16引腳一(yi)個邏(luo)輯高狀態(tai)，至少保持tSSU:B時間(jian)(jian)間(jian)(jian)隔來停(ting)止(zhi)傳輸。最后(hou)一(yi)個邏(luo)輯高狀態(tai)必須保持一(yi)個tCYCH:B時間(jian)(jian)間(jian)(jian)隔，以(yi)便有(you)時間(jian)(jian)讓塊傳輸完(wan)全停(ting)止(zhi)。

　　如果發(fa)生通信(xin)錯誤(wu)(e.g.，tCYCB>250μs)，主(zhu)機就發(fa)送給智能(neng)電池(chi)一個BREAK信(xin)號，讓(rang)其控(kong)制串(chuan)行接(jie)(jie)口。當(dang)HDQ16引腳在一個時間(jian)間(jian)隔，或(huo)者更(geng)長時間(jian)里為(wei)邏(luo)輯(ji)低狀(zhuang)(zhuang)態(tai)(tai)時，智能(neng)電池(chi)就會偵(zhen)測BREAK。然(ran)后(hou)(hou)，HDQ16引腳回到其正常預設高邏(luo)輯(ji)狀(zhuang)(zhuang)態(tai)(tai)一個tBR時間(jian)間(jian)隔。然(ran)后(hou)(hou)，智能(neng)電池(chi)就準備從主(zhu)機那里接(jie)(jie)收指令。

　　HDQ16引腳是開(kai)漏(lou)的，需要一(yi)個外部(bu)的上(shang)拉(la)電阻。

　　圖5是用(yong)邏輯分析儀(yi)顯示的一次HDQ總(zong)線上的通信波形。

　　本文(wen)提出的(de)充電(dian)(dian)系統從技(ji)術上很好地解決(jue)了(le)上述問題，通過LCD顯示屏(ping)可以清晰便捷地讀出電(dian)(dian)源(yuan)(yuan)的(de)剩余容量、已有充放(fang)電(dian)(dian)次數(shu)、充電(dian)(dian)及(ji)放(fang)電(dian)(dian)電(dian)(dian)流、電(dian)(dian)池電(dian)(dian)壓、容量統計(ji)和電(dian)(dian)池特(te)性等重要內容，并且通過設定，可以判斷電(dian)(dian)源(yuan)(yuan)是否達到報(bao)廢標準(zhun)，及(ji)時提醒操作者更(geng)新電(dian)(dian)源(yuan)(yuan)。為電(dian)(dian)源(yuan)(yuan)維護(hu)保養(yang)工作提供(gong)明(ming)確的(de)參(can)考數(shu)據(ju)，降(jiang)低了(le)對操作人員專業技(ji)術水平的(de)要求，保證了(le)列車尾部電(dian)(dian)源(yuan)(yuan)的(de)安全使用(yong)。