該器件面向單節鋰離子/聚合物電池應用。LT3651-4.2 接受高達 32V 的輸入，并具 40V 最大絕對額定值以增加系統裕度。充電電流可編程至高達 4A，而且是動態可調節的，而充分集成的同步電源電路最大限度地降低了功耗并節省了電路板空間。用戶可選定時器或 C/10 終止無需外部微控制器，簡化了設計。LT3651-4.2 不需要外部高準確度電阻器來設定浮置電壓，從而進一步節省了成本和空間。應用包括工業手持式儀表、12V 至 24V 汽車和重型設備應用、臺式插座充電器以(yi)及筆(bi)記本或(huo)平板電腦。

　　LT3651-4.2 的可編(bian)程開關頻率(lv) (200kHz 至(zhi) 1MHz) 使設計師能平衡解(jie)決方(fang)案(an)尺寸、功率(lv)損耗(hao)和(he)(he)濾波(bo)需求。同步(bu)工(gong)作實現(xian)了高達 90% 的充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)效率(lv)。最(zui)終浮置(zhi)電(dian)(dian)(dian)(dian)(dian)壓準確(que)度為 ±0.5%，充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流準確(que)度為 ±7.5%，以(yi)及(ji) C/10 檢測準確(que)度為 ±4%。一旦(dan)充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)終止，LT3651-4.2 就自動地進(jin)入(ru)(ru)低電(dian)(dian)(dian)(dian)(dian)流備(bei)用(yong)模(mo)式(shi)，該模(mo)式(shi)將輸(shu)(shu)入(ru)(ru)電(dian)(dian)(dian)(dian)(dian)源電(dian)(dian)(dian)(dian)(dian)流降(jiang)至(zhi) 80uA。停機(ji)時，輸(shu)(shu)入(ru)(ru)偏置(zhi)電(dian)(dian)(dian)(dian)(dian)流降(jiang)至(zhi) 15uA。由于在(zai)所有(you)非充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)周期中(zhong)僅從電(dian)(dian)(dian)(dian)(dian)池泄漏(lou) <1uA 的電(dian)(dian)(dian)(dian)(dian)流，所以(yi) LT3651-4.2 可最(zui)大限度地延長電(dian)(dian)(dian)(dian)(dian)池壽命(ming)。就安全性(xing)和(he)(he)自主充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)控制而言，該器件(jian)包(bao)括自動重啟和(he)(he)預處理、一個(ge)用(yong)于溫度合格充(chong)(chong)電(dian)(dian)(dian)(dian)(dian)的熱敏(min)電(dian)(dian)(dian)(dian)(dian)阻輸(shu)(shu)入(ru)(ru)、可編(bian)程輸(shu)(shu)入(ru)(ru)電(dian)(dian)(dian)(dian)(dian)流限制、壞電(dian)(dian)(dian)(dian)(dian)池檢測以(yi)及(ji)二進(jin)制編(bian)碼的狀(zhuang)態(tai)輸(shu)(shu)出引腳(jiao)。

　　LT3651-4.2 采(cai)用扁平(ping) (0.75mm) 36 引腳 5mm x 6mm QFN 封裝，同(tong)時提供 E 級和I 級版(ban)本，保(bao)證工作在(zai) -40°C 至 125°C 溫度范(fan)圍。千片批購價(jia)分別(bie)為(wei)每片 4.13 美(mei)元和 4.75 美(mei)元。兩節 8.2V 和 8.4V 版(ban)本以及一節 4.1V 版(ban)本計劃在(zai)未來(lai) 2 至 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

　　性(xing)能概要：LT3651-4.2

　　寬輸入(ru)電壓(ya)范圍：4.75V 至 32V (40V 絕(jue)對最大額定值)

　　可編(bian)程充電(dian)電(dian)流高達 4A

　　單節鋰離(li)子/聚合物電池充電功能，4.2V 充電電壓(ya)

　　同(tong)步(bu)整流提高充電效(xiao)率

　　用戶(hu)可選終止：C/10 或可編程終止定時器

　　可編程開關頻(pin)率(lv) (200kHz 至 1MHz)

　　可編程輸入電流限制

　　±0.5% 充電電壓準確(que)度

　　±7.5% 充(chong)電電流準(zhun)確度

　　±4% C/10 檢(jian)測準(zhun)確度(du)

　　NTC 電阻器溫度監視器

　　自動再充電

　　自動預處理

　　二進(jin)制編碼集(ji)電極開路充電狀態引(yin)腳

　　具(ju)自動復位(wei)的壞電池檢測

　　扁平 (0.75mm) 5mm x 6mm QFN-36 封(feng)裝