同步降壓型電池充電器
高效率、4A單片同步降壓型電池充電器LT3651-4.2，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、臺式插座充電器以及筆記本或平板電腦。
LT3651-4.2的可編(bian)程開關頻率(lv)(200kHz至(zhi)1MHz)使設計師(shi)能平衡解決方案尺寸、功率(lv)損耗和(he)(he)濾波需求(qiu)。同步工作實現了高達90%的充(chong)(chong)電(dian)(dian)(dian)效率(lv)。最終浮置電(dian)(dian)(dian)壓準確度(du)(du)為?0.5%，充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流準確度(du)(du)為?7.5%，以(yi)及(ji)C/10檢測準確度(du)(du)為?4%。一旦充(chong)(chong)電(dian)(dian)(dian)終止(zhi)，LT3651-4.2就自(zi)動地進入(ru)低(di)電(dian)(dian)(dian)流備用(yong)模式(shi)(shi)，該模式(shi)(shi)將輸入(ru)電(dian)(dian)(dian)源電(dian)(dian)(dian)流降至(zhi)80uA。停機(ji)時，輸入(ru)偏置電(dian)(dian)(dian)流降至(zhi)15uA。由于在所(suo)有非充(chong)(chong)電(dian)(dian)(dian)周期中僅從電(dian)(dian)(dian)池(chi)泄漏<1uA的電(dian)(dian)(dian)流，所(suo)以(yi)LT3651-4.2可最大(da)限度(du)(du)地延長電(dian)(dian)(dian)池(chi)壽命。就安全(quan)性和(he)(he)自(zi)主(zhu)充(chong)(chong)電(dian)(dian)(dian)控(kong)制而言，該器(qi)件包括自(zi)動重啟和(he)(he)預處理、一個用(yong)于溫度(du)(du)合格充(chong)(chong)電(dian)(dian)(dian)的熱敏(min)電(dian)(dian)(dian)阻輸入(ru)、可編(bian)程輸入(ru)電(dian)(dian)(dian)流限制、壞電(dian)(dian)(dian)池(chi)檢測以(yi)及(ji)二進制編(bian)碼的狀態輸出引腳。
LT3651-4.2采(cai)用扁平(ping)(0.75mm)36引腳5mmx6mmQFN封裝，同時提供E級(ji)(ji)和(he)I級(ji)(ji)版(ban)本，保證工作(zuo)在-40?C至(zhi)125?C溫度范圍(wei)。千片(pian)批(pi)購價分別為每片(pian)4.13美元和(he)4.75美元。兩節8.2V和(he)8.4V版(ban)本以及一節4.1V版(ban)本計劃在未來(lai)2至(zhi)3個(ge)月內(nei)推出。
32V、4A同步單片式單節鋰離子電池充電器
性能(neng)概(gai)要：LT3651-4.2
?寬輸(shu)入電壓(ya)范圍(wei)：4.75V至32V(40V絕對最大額定值)
?可編(bian)程充電(dian)電(dian)流高達4A
?單節鋰離子/聚合物電(dian)池充電(dian)功能，4.2V充電(dian)電(dian)壓
?同步整流提高充電(dian)效率
?用戶可選(xuan)終止：C/10或可編程終止定時器
?可編程開關頻(pin)率(200kHz至1MHz)
?可(ke)編程輸(shu)入(ru)電流限(xian)制
??0.5%充(chong)電(dian)(dian)電(dian)(dian)壓(ya)準確度(du)
??7.5%充電電流(liu)準確(que)度
??4%C/10檢測準確度
?NTC電阻器(qi)溫度監(jian)視器(qi)
?自(zi)動再充電
?自動(dong)預(yu)處(chu)理
?二進制編碼集電(dian)(dian)極開路充電(dian)(dian)狀態引腳(jiao)
?具自動(dong)復位的(de)壞電池(chi)檢(jian)測(ce)
?扁(bian)平(0.75mm)5mmx6mmQFN-36封裝