自主式高效率電源管理器、理想二極管控制器和電池充電器LTC4098 該(gai)器(qi)(qi)件(jian)用于由USB供電(dian)(dian)(dian)(dian)的(de)便攜式設備，如媒體(ti)播放(fang)器(qi)(qi)、數(shu)碼(ma)相(xiang)機、PDA、個人(ren)導航器(qi)(qi)和(he)智能電(dian)(dian)(dian)(dian)話。LTC4098的(de)開(kai)關拓(tuo)撲具有(you)電(dian)(dian)(dian)(dian)源(yuan)通路(PowerPath)控(kong)制，可(ke)無縫地(di)管理交流適配器(qi)(qi)或(huo)USB端口(kou)和(he)設備的(de)鋰離子(zi)/聚合(he)物(wu)電(dian)(dian)(dian)(dian)池之(zhi)間的(de)電(dian)(dian)(dian)(dian)源(yuan)流動，同時優先向(xiang)系統負載供電(dian)(dian)(dian)(dian)。就汽車、Firewire或(huo)其它高(gao)(gao)(gao)壓(ya)(ya)應用而言，LTC4098對凌(ling)力(li)爾特公司(si)高(gao)(gao)(gao)達(da)38V工作輸入(60V 瞬(shun)態)的(de)伴隨開(kai)關穩壓(ya)(ya)器(qi)(qi)提(ti)供電(dian)(dian)(dian)(dian)池跟蹤(Bat-Track)控(kong)制，從而最大(da)限(xian)度地(di)提(ti)高(gao)(gao)(gao)了電(dian)(dian)(dian)(dian)池充電(dian)(dian)(dian)(dian)器(qi)(qi)的(de)效率、最大(da)限(xian)度地(di)減少了熱量，并可(ke)以在USB和(he)較(jiao)高(gao)(gao)(gao)壓(ya)(ya)電(dian)(dian)(dian)(dian)源(yuan)之(zhi)間無縫轉換。

　　LTC4098僅需(xu)要(yao)一個外部NFET/電(dian)(dian)阻組合就(jiu)可在USB輸(shu)入(ru)提供高(gao)達66V的過壓(ya)保護(OVP)電(dian)(dian)路(lu)，以(yi)防止意外的高(gao)壓(ya)應用所引起的損壞。

　　LTC4098的(de)“即時(shi)(shi)接通”工(gong)作確保一插上電源(yuan)就向系統(tong)負載供電，甚(shen)至在電池沒電時(shi)(shi)也一樣(yang)。其內置的(de)理想二(er)極管保證(zheng)總是向VOUT提供充(chong)足的(de)功(gong)率，即使LTC4098兩個輸入引腳功(gong)率不充(chong)足也一樣(yang)。該集成電路的(de)理想二(er)極管控(kong)制器(qi)可用來驅動可選(xuan)PFET的(de)柵極，從而將對電池的(de)阻抗降至30mΩ或更低。

　　LTC4098的全功能單節鋰離子/聚合物電池充電器允許負載電(dian)(dian)(dian)(dian)流(liu)超過從USB端口(kou)吸取的(de)電(dian)(dian)(dian)(dian)流(liu)，同(tong)時符合(he)USB負載規范。就快速充(chong)電(dian)(dian)(dian)(dian)而(er)言，該集(ji)成(cheng)(cheng)電(dian)(dian)(dian)(dian)路(lu)的(de)開關輸(shu)入(ru)級(ji)幾(ji)乎將從USB端口(kou)獲(huo)得(de)的(de)所有(you)2.5W功率(lv)都(dou)轉換(huan)成(cheng)(cheng)系統電(dian)(dian)(dian)(dian)流(liu)，從而(er)用(yong)限制(zhi)到500mA的(de)USB端口(kou)實(shi)現了高達700mA的(de)電(dian)(dian)(dian)(dian)流(liu)。用(yong)交(jiao)流(liu)適配器(qi)(qi)供電(dian)(dian)(dian)(dian)時，還有(you)1.5A充(chong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)可(ke)用(yong)。另外，該充(chong)電(dian)(dian)(dian)(dian)器(qi)(qi)具(ju)有(you)熱量限制(zhi)、可(ke)自動(dong)再充(chong)電(dian)(dian)(dian)(dian)、用(yong)自動(dong)充(chong)電(dian)(dian)(dian)(dian)終止(zhi)和固定(ding)持續時間(jian)安全(quan)定(ding)時器(qi)(qi)實(shi)現獨立(li)工(gong)作、能以(yi)低(di)壓涓(juan)流(liu)充(chong)電(dian)(dian)(dian)(dian)、可(ke)檢測壞(huai)電(dian)(dian)(dian)(dian)池并具(ju)有(you)一個熱敏電(dian)(dian)(dian)(dian)阻輸(shu)入(ru)以(yi)實(shi)現溫度合(he)格的(de)充(chong)電(dian)(dian)(dian)(dian)。該集(ji)成(cheng)(cheng)電(dian)(dian)(dian)(dian)路(lu)的(de)其它特點(dian)包(bao)括(kuo)：具(ju)有(you)一個暫(zan)停LDO以(yi)防止(zhi)設備連接到暫(zan)停USB端口(kou)時泄漏電(dian)(dian)(dian)(dian)池電(dian)(dian)(dian)(dian)量。

　　LTC4098采(cai)用超薄(0.55mm)20引腳3mm x 4mm QFN封裝(zhuang)，保證在-40℃至85℃的溫度范圍內工作。以1,000片為單位(wei)批量(liang)購(gou)買，每片價格為2.50美(mei)元(yuan)。

　　LTC4098性能概(gai)要：

　　具電(dian)(dian)池(chi)跟蹤自適應輸出(chu)控(kong)制(zhi)的(de)開關穩壓(ya)器充(chong)分(fen)利用(yong)USB端口提(ti)供的(de)有限功率為(wei)電(dian)(dian)池(chi)充(chong)電(dian)(dian)以及為(wei)應用(yong)提(ti)供電(dian)(dian)源

　　過壓保護(高達66V)防止(zhi)器(qi)件(jian)損(sun)壞

　　電池跟蹤外(wai)部降(jiang)壓(ya)型開關穩壓(ya)器(qi)控制在使(shi)用(yong)汽車、Firewire和其它高(gao)(gao)壓(ya)源(高(gao)(gao)達38V連(lian)續電壓(ya)，60V瞬態)時最大(da)限(xian)度提(ti)高(gao)(gao)效率

　　180mΩ內部理想(xiang)二(er)極管和(he)外(wai)部理想(xiang)二(er)極管控(kong)制器(qi)在輸入功率(lv)受限或不提供時(shi)可無縫地提供低損耗電源通路

　　全功能鋰離子/聚合物電池充電器

　　從(cong)交流(liu)適配器提供(gong)1.5A最(zui)大(da)充電(dian)電(dian)流(liu)，并具熱量限制(zhi)

　　從500mA USB端(duan)口向系統負載提供700mA最大電流

　　轉換控制(zhi)降低開(kai)關EMI

　　超薄(bo)(0.55mm) 20引(yin)線3mm x 4mm QFN封裝