4A 單片同步降壓型電池充電器 LT3651-4.2，該器(qi)件面向(xiang)單節鋰離子(zi)/聚合物(wu)電(dian)(dian)池應(ying)用。LT3651-4.2 接受高達 32V 的(de)輸入，并具 40V 最大(da)絕對額(e)定值以(yi)(yi)增加系統裕(yu)度。充電(dian)(dian)電(dian)(dian)流可(ke)編程至(zhi)高達 4A，而且是動態可(ke)調節的(de)，而充分集(ji)成的(de)同步電(dian)(dian)源(yuan)電(dian)(dian)路最大(da)限度地降低(di)了(le)(le)(le)功耗并節省了(le)(le)(le)電(dian)(dian)路板空間。用戶可(ke)選定時器(qi)或 C/10 終止無需(xu)外部微(wei)控制器(qi)，簡(jian)化了(le)(le)(le)設計。LT3651-4.2 不(bu)需(xu)要外部高準確度電(dian)(dian)阻器(qi)來設定浮置電(dian)(dian)壓，從而進一步節省了(le)(le)(le)成本和空間。應(ying)用包括工業手持(chi)式(shi)儀表(biao)、12V 至(zhi) 24V 汽(qi)車(che)和重型設備(bei)應(ying)用、臺式(shi)插座充電(dian)(dian)器(qi)以(yi)(yi)及筆記本或平(ping)板電(dian)(dian)腦。

　　LT3651-4.2 的(de)可編程開關頻率 (200kHz 至(zhi) 1MHz) 使設計(ji)師能平(ping)衡解決方案(an)尺寸、功率損耗(hao)和濾波需求。同步工(gong)作實現了高達 90% 的(de)充電(dian)(dian)(dian)(dian)(dian)效(xiao)率。最(zui)終浮(fu)置電(dian)(dian)(dian)(dian)(dian)壓準確度(du)(du)為 ?0.5%，充電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)準確度(du)(du)為 ?7.5%，以及(ji) C/10 檢測準確度(du)(du)為 ?4%。一旦充電(dian)(dian)(dian)(dian)(dian)終止，LT3651-4.2 就自動地進入(ru)低電(dian)(dian)(dian)(dian)(dian)流(liu)備(bei)用(yong)模式，該(gai)模式將輸入(ru)電(dian)(dian)(dian)(dian)(dian)源電(dian)(dian)(dian)(dian)(dian)流(liu)降至(zhi) 80uA。停機(ji)時(shi)，輸入(ru)偏(pian)置電(dian)(dian)(dian)(dian)(dian)流(liu)降至(zhi) 15uA。由于(yu)在(zai)所(suo)有非充電(dian)(dian)(dian)(dian)(dian)周期中僅(jin)從(cong)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)泄漏 <1uA 的(de)電(dian)(dian)(dian)(dian)(dian)流(liu)，所(suo)以 LT3651-4.2 可最(zui)大限度(du)(du)地延(yan)長(chang)電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)壽命。就安(an)全性和自主充電(dian)(dian)(dian)(dian)(dian)控制而(er)言(yan)，該(gai)器件包括(kuo)自動重啟和預處理、一個用(yong)于(yu)溫度(du)(du)合格充電(dian)(dian)(dian)(dian)(dian)的(de)熱敏電(dian)(dian)(dian)(dian)(dian)阻輸入(ru)、可編程輸入(ru)電(dian)(dian)(dian)(dian)(dian)流(liu)限制、壞電(dian)(dian)(dian)(dian)(dian)池(chi)(chi)檢測以及(ji)二進制編碼(ma)的(de)狀(zhuang)態輸出(chu)引腳。

　　LT3651-4.2 采用(yong)扁平 (0.75mm) 36 引腳 5mm x 6mm QFN 封裝，同時(shi)提(ti)供 E 級和(he)I 級版本，保證工作在(zai) -40?C 至(zhi)(zhi) 125?C 溫度范圍。千片(pian)批購價分別為(wei)每片(pian) 4.13 美元(yuan)(yuan)和(he) 4.75 美元(yuan)(yuan)。兩節 8.2V 和(he) 8.4V 版本以及一節 4.1V 版本計劃在(zai)未(wei)來 2 至(zhi)(zhi) 3 個月內推出。

照片說明： 32V、4A 同步單片式單節鋰離子電池充電器