4A 單片同步降壓型電池充電器 LT3651-4.2，該器(qi)(qi)件面向單節鋰離子(zi)/聚(ju)合物電池應(ying)(ying)用(yong)(yong)。LT3651-4.2 接受(shou)高達(da) 32V 的輸入，并具 40V 最(zui)大絕對額定(ding)值(zhi)以增加系統(tong)裕度。充(chong)(chong)電電流可(ke)編程至高達(da) 4A，而且(qie)是動態可(ke)調節的，而充(chong)(chong)分(fen)集成的同步電源電路最(zui)大限度地降(jiang)低了(le)(le)功耗并節省了(le)(le)電路板空(kong)(kong)間。用(yong)(yong)戶可(ke)選定(ding)時器(qi)(qi)或 C/10 終止無需外部微控制(zhi)器(qi)(qi)，簡化(hua)了(le)(le)設計。LT3651-4.2 不需要外部高準確度電阻(zu)器(qi)(qi)來設定(ding)浮置電壓，從而進一步節省了(le)(le)成本(ben)和(he)空(kong)(kong)間。應(ying)(ying)用(yong)(yong)包(bao)括工業(ye)手(shou)持式(shi)儀(yi)表、12V 至 24V 汽車(che)和(he)重(zhong)型設備應(ying)(ying)用(yong)(yong)、臺式(shi)插座充(chong)(chong)電器(qi)(qi)以及筆記(ji)本(ben)或平板電腦(nao)。

　　LT3651-4.2 的(de)(de)可(ke)編程(cheng)開關頻率(lv) (200kHz 至 1MHz) 使設(she)計師能平(ping)衡解決(jue)方案尺寸、功率(lv)損(sun)耗和(he)(he)(he)濾波需求。同步工作實現了高達 90% 的(de)(de)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)效(xiao)率(lv)。最終浮(fu)置(zhi)(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓準確(que)(que)度(du)(du)(du)為(wei) ?0.5%，充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)準確(que)(que)度(du)(du)(du)為(wei) ?7.5%，以(yi)及(ji) C/10 檢測準確(que)(que)度(du)(du)(du)為(wei) ?4%。一旦充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)終止，LT3651-4.2 就自(zi)(zi)動(dong)地(di)進入(ru)低電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)備用(yong)模(mo)式，該(gai)模(mo)式將輸(shu)入(ru)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)源電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)降(jiang)至 80uA。停(ting)機時，輸(shu)入(ru)偏置(zhi)(zhi)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)降(jiang)至 15uA。由(you)于(yu)在所(suo)有非(fei)充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)周期中僅從電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池泄(xie)漏 <1uA 的(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)，所(suo)以(yi) LT3651-4.2 可(ke)最大限度(du)(du)(du)地(di)延(yan)長電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池壽命。就安全性和(he)(he)(he)自(zi)(zi)主充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)控制而言，該(gai)器件(jian)包(bao)括自(zi)(zi)動(dong)重(zhong)啟和(he)(he)(he)預處理(li)、一個(ge)用(yong)于(yu)溫度(du)(du)(du)合(he)格充(chong)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)的(de)(de)熱敏電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)阻輸(shu)入(ru)、可(ke)編程(cheng)輸(shu)入(ru)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)限制、壞電(dian)(dian)(dian)(dian)(dian)(dian)(dian)(dian)池檢測以(yi)及(ji)二(er)進制編碼的(de)(de)狀態輸(shu)出(chu)引(yin)腳。

　　LT3651-4.2 采用扁(bian)平 (0.75mm) 36 引腳 5mm x 6mm QFN 封裝，同時提供 E 級和I 級版本(ben)，保證工作在(zai) -40?C 至 125?C 溫度范(fan)圍(wei)。千(qian)片批(pi)購價分別為每片 4.13 美元(yuan)和 4.75 美元(yuan)。兩節(jie) 8.2V 和 8.4V 版本(ben)以及一節(jie) 4.1V 版本(ben)計劃在(zai)未來 2 至 3 個月內推(tui)出。

照片說明： 32V、4A 同步單片式單節鋰離子電池充電器