4A 單片同步降壓型電池充電器 LT3651-4.2，該器(qi)件(jian)面向單節(jie)(jie)鋰(li)離子/聚合物電(dian)(dian)池應用(yong)。LT3651-4.2 接受高達 32V 的(de)輸(shu)入(ru)，并(bing)具(ju) 40V 最大絕對額定(ding)值以增加系統裕度(du)。充(chong)電(dian)(dian)電(dian)(dian)流可(ke)編程至(zhi)高達 4A，而(er)且是動態可(ke)調節(jie)(jie)的(de)，而(er)充(chong)分集成的(de)同(tong)步(bu)電(dian)(dian)源電(dian)(dian)路(lu)最大限度(du)地(di)降低了功耗(hao)并(bing)節(jie)(jie)省(sheng)了電(dian)(dian)路(lu)板(ban)空間。用(yong)戶可(ke)選定(ding)時器(qi)或 C/10 終(zhong)止無需外部微控制器(qi)，簡化了設計。LT3651-4.2 不(bu)需要外部高準(zhun)確度(du)電(dian)(dian)阻器(qi)來設定(ding)浮置電(dian)(dian)壓，從而(er)進一步(bu)節(jie)(jie)省(sheng)了成本和(he)空間。應用(yong)包括(kuo)工業手持式(shi)儀表、12V 至(zhi) 24V 汽(qi)車和(he)重(zhong)型設備應用(yong)、臺式(shi)插座充(chong)電(dian)(dian)器(qi)以及筆記本或平板(ban)電(dian)(dian)腦。

　　LT3651-4.2 的(de)可(ke)編程(cheng)開關頻率(lv) (200kHz 至 1MHz) 使設計師能平衡解決方案尺寸、功率(lv)損耗和(he)濾波(bo)需求(qiu)。同步工作實(shi)現了(le)高達(da) 90% 的(de)充電(dian)(dian)(dian)(dian)(dian)效率(lv)。最終浮置(zhi)電(dian)(dian)(dian)(dian)(dian)壓準(zhun)確(que)度(du)為(wei)(wei) ?0.5%，充電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流(liu)準(zhun)確(que)度(du)為(wei)(wei) ?7.5%，以及(ji) C/10 檢(jian)測準(zhun)確(que)度(du)為(wei)(wei) ?4%。一(yi)旦充電(dian)(dian)(dian)(dian)(dian)終止，LT3651-4.2 就(jiu)自動(dong)地進入(ru)低(di)電(dian)(dian)(dian)(dian)(dian)流(liu)備用模式，該模式將(jiang)輸(shu)入(ru)電(dian)(dian)(dian)(dian)(dian)源電(dian)(dian)(dian)(dian)(dian)流(liu)降至 80uA。停機時(shi)，輸(shu)入(ru)偏置(zhi)電(dian)(dian)(dian)(dian)(dian)流(liu)降至 15uA。由于(yu)在所有非充電(dian)(dian)(dian)(dian)(dian)周期(qi)中僅(jin)從電(dian)(dian)(dian)(dian)(dian)池(chi)泄漏(lou) <1uA 的(de)電(dian)(dian)(dian)(dian)(dian)流(liu)，所以 LT3651-4.2 可(ke)最大限度(du)地延(yan)長電(dian)(dian)(dian)(dian)(dian)池(chi)壽命。就(jiu)安(an)全性(xing)和(he)自主充電(dian)(dian)(dian)(dian)(dian)控制(zhi)(zhi)而言(yan)，該器件包括自動(dong)重(zhong)啟和(he)預處理、一(yi)個用于(yu)溫度(du)合格(ge)充電(dian)(dian)(dian)(dian)(dian)的(de)熱(re)敏電(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)流(liu)限制(zhi)(zhi)、壞(huai)電(dian)(dian)(dian)(dian)(dian)池(chi)檢(jian)測以及(ji)二進制(zhi)(zhi)編碼的(de)狀態輸(shu)出引腳。

　　LT3651-4.2 采用(yong)扁(bian)平 (0.75mm) 36 引腳 5mm x 6mm QFN 封裝，同(tong)時提供 E 級和(he)(he)I 級版本(ben)，保證(zheng)工作在(zai) -40?C 至(zhi) 125?C 溫度范圍。千(qian)片批購價分別為每(mei)片 4.13 美(mei)元(yuan)和(he)(he) 4.75 美(mei)元(yuan)。兩節 8.2V 和(he)(he) 8.4V 版本(ben)以及一節 4.1V 版本(ben)計劃在(zai)未來 2 至(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