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以(yi)對這兩(liang)(liang)種電(dian)(dian)池(chi)(chi)進行(xing)充(chong)(chong)(chong)電(dian)(dian)，對鎳鎘(ge)電(dian)(dian)池(chi)(chi)組采用脈(mo)沖充(chong)(chong)(chong)電(dian)(dian)方(fang)式，對鋰電(dian)(dian)池(chi)(chi)組采用恒(heng)流充(chong)(chong)(chong)電(dian)(dian)方(fang)式，這是依(yi)據電(dian)(dian)池(chi)(chi)的(de)不(bu)同機理而設計的(de)，真正做(zuo)到了(le)(le)一(yi)機兩(liang)(liang)用，此(ci)為(wei)該(gai)充(chong)(chong)(chong)電(dian)(dian)器(qi)的(de)創新(xin)點(dian)，也是設計的(de)難(nan)點(dian)。充(chong)(chong)(chong)電(dian)(dian)器(qi)的(de)寬屏LCD可以(yi)同時顯(xian)示4組充(chong)(chong)(chong)電(dian)(dian)器(qi)的(de)充(chong)(chong)(chong)電(dian)(dian)狀(zhuang)態，也可單獨顯(xian)示一(yi)組充(chong)(chong)(chong)電(dian)(dian)器(qi)上電(dian)(dian)池(chi)(chi)的(de)各(ge)項參(can)數，做(zuo)到了(le)(le)對電(dian)(dian)池(chi)(chi)充(chong)(chong)(chong)電(dian)(dian)過程的(de)實時監測。

　　系統整體設計

　　系統設計目(mu)標是：

　　1．可(ke)同時對4組8.4V的(de)鋰離子(zi)電(dian)池或9.2V的(de)鎳鎘電(dian)池進行(xing)充(chong)放電(dian)。

　　2．可與電池(chi)組中的芯片(pian)通信(xin)，判(pan)斷(duan)電池(chi)的化學性(xing)質。

　　3．對于不同化學(xue)性質的(de)電(dian)池，將(jiang)采(cai)用相(xiang)應(ying)的(de)充(chong)電(dian)方式(shi)。

　　4．可與電(dian)(dian)池組中的(de)芯片(pian)通信，得到該(gai)電(dian)(dian)池組的(de)電(dian)(dian)壓(ya)、充電(dian)(dian)電(dian)(dian)流(liu)、容量等參數。

　　5．充電器帶有LCD，可顯示(shi)電(dian)池的各項數據。

　　該充(chong)電器(qi)的功能框圖如圖1所(suo)示。

　　
     ;  系統硬件設計

　　總控單元的(de)設計與(yu)實(shi)現

　　總控(kong)單元是由(you)微控(kong)制器(qi)PIC16F873和(he)鍵盤控(kong)制芯片ZLG7289A構成的。主要任務是負責與各(ge)

個充電(dian)單元(yuan)通信(xin)，并處理用(yong)戶輸入與(yu)(yu)LCD顯(xian)示信(xin)息(xi)。鍵(jian)盤控制芯片在這(zhe)里負責(ze)6個按鍵(jian)和(he)12個LED的控制。ZLG7289A與(yu)(yu)微控制器之(zhi)間通過(guo)SPI總線進(jin)行雙向通信(xin)。主(zhu)控單元(yuan)每秒查詢一次各個充電(dian)單元(yuan)，獲取當前充電(dian)單元(yuan)的信(xin)息(xi)，如有(you)無電(dian)池、電(dian)池性質、電(dian)池電(dian)壓(ya)等。之(zhi)后由(you)LCD模塊(kuai)向用(yong)戶顯(xian)示。

　　充電單元的設(she)計與實現(xian)

　　LTC4002鋰離子電池充電控制芯片

　　LTC4002是(shi)一款高(gao)(gao)效(xiao)獨立開關(guan)模式鋰離子電(dian)(dian)池充(chong)電(dian)(dian)控(kong)(kong)制器(qi)。該控(kong)(kong)制器(qi)有4.2V和8.4V兩個(ge)版本(ben)。LTC4002-8.4具有500kHz開關(guan)頻(pin)率，是(shi)高(gao)(gao)效(xiao)電(dian)(dian)流(liu)模式的(de)PWM控(kong)(kong)制器(qi)。通過(guo)驅(qu)動(dong)一個(ge)外部P溝(gou)道(dao)MOSFET，它可以(yi)提(ti)供(gong)4A的(de)充(chong)電(dian)(dian)電(dian)(dian)流(liu)，而效(xiao)率可高(gao)(gao)達90％。輸(shu)出(chu)電(dian)(dian)壓設置為8.4V，最終浮(fu)動(dong)電(dian)(dian)壓并具1％的(de)精度(du)，而充(chong)電(dian)(dian)準確度(du)為5％。此外，該器(qi)件可在9V～22V范(fan)圍內的(de)多種(zhong)墻上適配器(qi)上運行(xing)。與遲滯拓撲結構(gou)(gou)充(chong)電(dian)(dian)器(qi)相比，LTC4002-8.4的(de)快(kuai)速(su)運行(xing)頻(pin)率與電(dian)(dian)流(liu)模式架(jia)構(gou)(gou)使(shi)之(zhi)能夠使(shi)用小型電(dian)(dian)感器(qi)和電(dian)(dian)容器(qi)。

　　鋰離子／鎳(nie)鎘電池兩用充電單元的總體設計

　　從(cong)前(qian)面對(dui)LTC4002的分析可知，該芯片(pian)是針對(dui)鋰(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)的充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)控制(zhi)器，要(yao)實現對(dui)鎳(nie)鎘電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)需(xu)要(yao)解(jie)決(jue)以下問題：首(shou)先，LTC4002對(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)進(jin)(jin)行(xing)監(jian)測，保證電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)不超過(guo)8.4V。但(dan)對(dui)于鎳(nie)鎘電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)組(zu)，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)截止電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)可以達到9.2V。其(qi)次(ci)，鎳(nie)鎘電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)即將結束時，需(xu)要(yao)對(dui)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)進(jin)(jin)行(xing)以正常(chang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)30％和10％的涓(juan)流(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。所以，第二個需(xu)要(yao)解(jie)決(jue)的問題是如何控制(zhi)恒(heng)流(liu)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)大小。此外，對(dui)鎳(nie)鎘電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)應使用脈沖充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)方(fang)式(shi)。即以1s為周期，95％的時間用來充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，1％的時間用來放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)，其(qi)余(yu)時間不充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)也(ye)不放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)。最(zui)后，如何判斷某一個電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)是鋰(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)還是鎳(nie)鎘電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)，因(yin)為若(ruo)把鋰(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)誤(wu)判為鎳(nie)鎘電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)，會(hui)使充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)高于8.4V，這對(dui)鋰(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)是十分危險的，而將鎳(nie)鎘電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)誤(wu)判為鋰(li)離(li)(li)子(zi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)，則(ze)可能造成電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池(chi)(chi)(chi)(chi)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)不足。因(yin)此，必須保證極低的誤(wu)判率(lv)。

　　本部分根據LTC4002的(de)工(gong)作原(yuan)理(li)，設計(ji)了既可(ke)以(yi)(yi)對(dui)鋰離子(zi)電(dian)池(chi)(chi)進(jin)行恒流-恒壓充(chong)(chong)(chong)電(dian)，又可(ke)以(yi)(yi)對(dui)鎳鎘電(dian)池(chi)(chi)進(jin)行脈沖式充(chong)(chong)(chong)電(dian)的(de)電(dian)路(lu)。充(chong)(chong)(chong)電(dian)單元的(de)總體功(gong)能框圖(tu)如圖(tu)2所示。其中，信號調理(li)電(dian)路(lu)使充(chong)(chong)(chong)電(dian)器既可(ke)以(yi)(yi)對(dui)8.4V的(de)鋰電(dian)池(chi)(chi)充(chong)(chong)(chong)電(dian)，又可(ke)以(yi)(yi)對(dui)9.2V的(de)鎳鎘電(dian)池(chi)(chi)充(chong)(chong)(chong)電(dian)，同時(shi)也(ye)起(qi)到(dao)控制充(chong)(chong)(chong)電(dian)電(dian)流大(da)小(xiao)的(de)作用。

　　利用微控制器控制LTC4002的工作狀態，配(pei)合放電電路使充(chong)電器可以對鎳鎘電池(chi)進行脈沖(chong)方式充(chong)電。

　　微控制器通過一定(ding)的通信協議(HDQ16)與智能電池通信，確定(ding)其容量、化學性質(zhi)等關鍵參數。

　　信號調理電路的設計

　　為(wei)了(le)使(shi)LTC4002可對高于8.4V的(de)電(dian)池進(jin)行恒流充電(dian)，并可調(diao)(diao)節充電(dian)電(dian)流，在LTC4002的(de)BAT和SENSE端與采樣電(dian)阻之間(jian)加入一級信號(hao)調(diao)(diao)理電(dian)路。該(gai)電(dian)路的(de)主(zhu)要功能(neng)是(shi)對采樣電(dian)阻兩端的(de)信號(hao)進(jin)行運算，針對不同化學性質的(de)電(dian)池，將相(xiang)應(ying)的(de)信號(hao)送(song)給(gei)LTC4002。該(gai)信號(hao)調(diao)(diao)理電(dian)路如圖3所示。

這里定(ding)(ding)義采樣(yang)(yang)電(dian)(dian)(dian)阻兩端(duan)的(de)電(dian)(dian)(dian)壓值是(shi)VBAT和Vsense，那么充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)(liu)在采樣(yang)(yang)電(dian)(dian)(dian)阻上的(de)壓降(jiang)VRS為(wei)(wei)(wei)：VRS=Vsense-VBAT，該信號為(wei)(wei)(wei)減法(fa)(fa)器(qi)(qi)的(de)輸(shu)出(chu)(chu)。設乘(cheng)法(fa)(fa)器(qi)(qi)的(de)乘(cheng)系數(shu)為(wei)(wei)(wei)K，那么乘(cheng)法(fa)(fa)器(qi)(qi)的(de)輸(shu)出(chu)(chu)為(wei)(wei)(wei)KVRS。對于鋰子電(dian)(dian)(dian)池(chi)，二(er)選一(yi)(yi)(yi)開關(guan)將選通(tong)電(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)壓VBAT；對于鎳(nie)鎘電(dian)(dian)(dian)池(chi)，二(er)選一(yi)(yi)(yi)開關(guan)將選通(tong)7V恒(heng)定(ding)(ding)電(dian)(dian)(dian)壓。這里設二(er)選一(yi)(yi)(yi)模擬開關(guan)的(de)輸(shu)出(chu)(chu)為(wei)(wei)(wei)V1，那么加法(fa)(fa)器(qi)(qi)的(de)輸(shu)出(chu)(chu)Vs應為(wei)(wei)(wei)：Vs=KVRS+V1，這樣(yang)(yang)一(yi)(yi)(yi)來，送到(dao)LTC4002的(de)BAT和SENSE兩端(duan)的(de)電(dian)(dian)(dian)壓之差應為(wei)(wei)(wei)KVRS。只要正(zheng)確控(kong)制(zhi)K值，就可(ke)以(yi)(yi)使(shi)充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)(liu)為(wei)(wei)(wei)正(zheng)常充(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)(liu)的(de)1／K。因(yin)此，可(ke)以(yi)(yi)通(tong)過二(er)選一(yi)(yi)(yi)開關(guan)控(kong)制(zhi)電(dian)(dian)(dian)流(liu)(liu)為(wei)(wei)(wei)恒(heng)流(liu)(liu)充(chong)電(dian)(dian)(dian)時的(de)10％或30％。

　　對于LTC4002的(de)BAT端(duan)輸入值(zhi)，當(dang)開關選(xuan)通鋰離子電池(chi)時，BAT的(de)輸入即是電池(chi)電壓(ya)。此時，LTC4002可(ke)以控制(zhi)整個(ge)鋰離子的(de)充電過(guo)程。不需任何外界的(de)干預。

　　當開(kai)關選(xuan)通了7V恒定(ding)(ding)電(dian)(dian)(dian)(dian)壓(ya)后(hou)，BAT端的(de)輸入恒定(ding)(ding)為7V，此時(shi)，LTC4002無法知道電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)真實電(dian)(dian)(dian)(dian)壓(ya)，只認為電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya)為7V。所以(yi)(yi)，盡管電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya)高于8.4V，仍會以(yi)(yi)恒定(ding)(ding)電(dian)(dian)(dian)(dian)流(liu)對電(dian)(dian)(dian)(dian)池(chi)(chi)進行(xing)充(chong)電(dian)(dian)(dian)(dian)。在這種情況下，需要微控制器的(de)干預，否(fou)則，會造(zao)成電(dian)(dian)(dian)(dian)池(chi)(chi)的(de)過充(chong)。由于微控制器內部帶有(you)ADC，可(ke)以(yi)(yi)監測電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya)的(de)變化。當電(dian)(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)(dian)壓(ya)達(da)到(dao)指定(ding)(ding)值時(shi)，減小充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)，直至(zhi)電(dian)(dian)(dian)(dian)池(chi)(chi)充(chong)滿。這樣(yang)就(jiu)可(ke)以(yi)(yi)對9.2V的(de)鎳鎘電(dian)(dian)(dian)(dian)池(chi)(chi)進行(xing)充(chong)電(dian)(dian)(dian)(dian)了。

　　脈沖充放電(dian)電(dian)路的設計

　　由于(yu)LTC4002是恒流(liu)充(chong)(chong)電(dian)(dian)控(kong)(kong)制(zhi)(zhi)(zhi)芯(xin)片，因此(ci)，必須使(shi)用(yong)(yong)微(wei)控(kong)(kong)制(zhi)(zhi)(zhi)器控(kong)(kong)制(zhi)(zhi)(zhi)其(qi)充(chong)(chong)電(dian)(dian)使(shi)能(neng)引腳(jiao)(jiao)COMP。當(dang)需要LTC4002輸出充(chong)(chong)電(dian)(dian)脈沖時(shi)，使(shi)控(kong)(kong)制(zhi)(zhi)(zhi)COMP引腳(jiao)(jiao)的端口變(bian)為高阻態，使(shi)COMP引腳(jiao)(jiao)自行(xing)升至360mV以(yi)上時(shi)，便有充(chong)(chong)電(dian)(dian)電(dian)(dian)流(liu)輸出。放(fang)電(dian)(dian)時(shi)，必須將COMP引腳(jiao)(jiao)拉(la)低，使(shi)LTC4002關斷充(chong)(chong)電(dian)(dian)電(dian)(dian)流(liu)。之后，再打開放(fang)電(dian)(dian)電(dian)(dian)路。微(wei)控(kong)(kong)制(zhi)(zhi)(zhi)器選(xuan)用(yong)(yong)PIC16F873，它是一款基(ji)于(yu)Fla

sh的8位微(wei)控制器(qi)。內(nei)部有定時器(qi)、看門狗電路、10位ADC等模塊。

　　微(wei)控(kong)制器(qi)以1s為周期對鎳鎘(ge)電池進行脈沖充放(fang)電。

　　系統軟件設計

　　系統軟件總體設計(ji)

　　充(chong)電(dian)(dian)(dian)單(dan)元(yuan)中的(de)微控(kong)(kong)(kong)制(zhi)(zhi)器(qi)主要(yao)負責充(chong)電(dian)(dian)(dian)過(guo)程(cheng)的(de)控(kong)(kong)(kong)制(zhi)(zhi)和與總控(kong)(kong)(kong)板的(de)通信，程(cheng)序流程(cheng)如圖4所示。充(chong)電(dian)(dian)(dian)單(dan)元(yuan)首(shou)先判斷是(shi)否有電(dian)(dian)(dian)池(chi)(chi)，如果(guo)有電(dian)(dian)(dian)池(chi)(chi)放(fang)入，則判斷充(chong)放(fang)電(dian)(dian)(dian)狀態(tai)，默認(ren)是(shi)充(chong)電(dian)(dian)(dian)狀態(tai)，該狀態(tai)可由(you)總控(kong)(kong)(kong)單(dan)元(yuan)改變。若(ruo)充(chong)電(dian)(dian)(dian)單(dan)元(yuan)處(chu)于(yu)充(chong)電(dian)(dian)(dian)狀態(tai)，則繼(ji)續(xu)判斷電(dian)(dian)(dian)池(chi)(chi)的(de)化學性質(zhi)，針對不同的(de)電(dian)(dian)(dian)池(chi)(chi)采用不同的(de)充(chong)電(dian)(dian)(dian)方式。若(ruo)處(chu)于(yu)放(fang)電(dian)(dian)(dian)狀態(tai)，則對電(dian)(dian)(dian)池(chi)(chi)組進行(xing)放(fang)電(dian)(dian)(dian)，直到電(dian)(dian)(dian)池(chi)(chi)電(dian)(dian)(dian)壓低于(yu)閾值電(dian)(dian)(dian)壓后，轉為充(chong)電(dian)(dian)(dian)狀態(tai)。

　　除(chu)主(zhu)程序外，總控單(dan)元(yuan)與(yu)充(chong)電單(dan)元(yuan)的通(tong)信是在中(zhong)(zhong)斷服務(wu)程序中(zhong)(zhong)實(shi)現的。當充(chong)電單(dan)元(yuan)收到總控單(dan)元(yuan)的指令后，進(jin)入中(zhong)(zhong)斷。若指令是查詢(xun)數(shu)(shu)據指令，則向總控單(dan)元(yuan)發(fa)送需要的數(shu)(shu)據。若是充(chong)電狀態(tai)設置指令，則依據指令設置充(chong)電單(dan)元(yuan)的充(chong)電狀態(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(dian)單元(yuan)可(ke)以通過(guo)HDQ總(zong)線對(dui)智(zhi)能(neng)電(dian)池(chi)進行讀操(cao)作。HDQ16接口協(xie)議是基于指(zhi)(zhi)令(ling)(ling)的(de)(de)協(xie)議。一(yi)個處理(li)器(qi)發(fa)送8位(wei)(wei)(wei)指(zhi)(zhi)令(ling)(ling)碼給智(zhi)能(neng)電(dian)池(chi)，這個8位(wei)(wei)(wei)的(de)(de)指(zhi)(zhi)令(ling)(ling)碼由兩部分組(zu)成(cheng)，7位(wei)(wei)(wei)HDQ16指(zhi)(zhi)令(ling)(ling)碼(位(wei)(wei)(wei)0～6)和1位(wei)(wei)(wei)讀／寫(xie)指(zhi)(zhi)令(ling)(ling)。讀／寫(xie)指(zhi)(zhi)令(ling)(ling)指(zhi)(zhi)示智(zhi)能(neng) 電(dian)池(chi)存儲接下來的(de)(de)16位(wei)(wei)(wei)數據到(dao)一(yi)個指(zhi)(zhi)定的(de)(de)寄存器(qi)，或者從指(zhi)(zhi)定的(de)(de)寄存器(qi)輸出16位(wei)(wei)(wei)數據。在HDQ16里，數據字節(指(zhi)(zhi)令(ling)(ling))或者字(數據)的(de)(de)最不重要(yao)的(de)(de)位(wei)(wei)(wei)會優先傳輸。

　　一個塊的(de)傳(chuan)輸包括三個不同的(de)部(bu)分。第一部(bu)分經由主機或者智能(neng)電(dian)池把(ba)HDQ16引腳(jiao)置(zhi)邏(luo)輯低狀(zhuang)態一個tSTRH：B時間(jian)后開始發(fa)送。接(jie)下來(lai)的(de)部(bu)分是(shi)真正的(de)數據傳(chuan)輸，數據位在tDSU:B時間(jian)間(jian)隔里是(shi)有效的(de)，負邊界用來(lai)開始通信。數據位被保(bao)持(chi)一個tDH:DV時間(jian)間(jian)隔，以便(bian)允(yun)許主機或智能(neng)電(dian)池采樣數據位。

　　在(zai)負邊界開始(shi)通(tong)信后，最后一部(bu)分通(tong)過返回給HDQ16引腳一個邏(luo)(luo)輯高狀(zhuang)態(tai)，至少保(bao)持tSSU:B時(shi)間(jian)(jian)間(jian)(jian)隔(ge)來停止(zhi)傳輸。最后一個邏(luo)(luo)輯高狀(zhuang)態(tai)必(bi)須保(bao)持一個tCYCH:B時(shi)間(jian)(jian)間(jian)(jian)隔(ge)，以便有時(shi)間(jian)(jian)讓塊(kuai)傳輸完(wan)全停止(zhi)。

　　如果發生通(tong)信錯(cuo)誤(e.g.，tCYCB>250μs)，主機(ji)(ji)就發送給智(zhi)(zhi)能(neng)電池(chi)一個BREAK信號，讓其(qi)控制串行接口(kou)。當HDQ16引腳(jiao)在(zai)一個時(shi)間(jian)(jian)間(jian)(jian)隔，或者更長時(shi)間(jian)(jian)里為邏輯低狀態時(shi)，智(zhi)(zhi)能(neng)電池(chi)就會(hui)偵測BREAK。然(ran)后，HDQ16引腳(jiao)回到其(qi)正(zheng)常預(yu)設高邏輯狀態一個tBR時(shi)間(jian)(jian)間(jian)(jian)隔。然(ran)后，智(zhi)(zhi)能(neng)電池(chi)就準(zhun)備從(cong)主機(ji)(ji)那里接收指令。

　　HDQ16引腳是開漏的，需要(yao)一個外部的上(shang)拉電阻。

　　圖(tu)5是用(yong)邏輯分析儀顯示的一次HDQ總線上的通信波形。

　　本文提(ti)出的充(chong)電(dian)(dian)(dian)系統(tong)從(cong)技(ji)術上很好地(di)解決了上述問(wen)題，通過LCD顯(xian)示屏可以(yi)清晰便捷地(di)讀出電(dian)(dian)(dian)源(yuan)的剩余容量(liang)、已(yi)有(you)充(chong)放(fang)電(dian)(dian)(dian)次數(shu)、充(chong)電(dian)(dian)(dian)及(ji)放(fang)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu)、電(dian)(dian)(dian)池(chi)電(dian)(dian)(dian)壓、容量(liang)統(tong)計和電(dian)(dian)(dian)池(chi)特性等重要內(nei)容，并且通過設定，可以(yi)判斷(duan)電(dian)(dian)(dian)源(yuan)是否達到(dao)報廢標準，及(ji)時提(ti)醒操作者(zhe)更新電(dian)(dian)(dian)源(yuan)。為(wei)電(dian)(dian)(dian)源(yuan)維護保養工作提(ti)供明確的參考數(shu)據，降低了對操作人員專業技(ji)術水平的要求，保證了列車(che)尾部電(dian)(dian)(dian)源(yuan)的安全使用。