凌力(li)爾特公司 (Linear Technology Corporation) 推出大(da)(da)功(gong)(gong)(gong)(gong)率(lv)(lv)(lv)、I2C 控制(zhi)和高效(xiao)率(lv)(lv)(lv)的(de)(de)電(dian)(dian)源通(tong)路 (PowerPath?) 管(guan)理器(qi)、理想二(er)極管(guan)控制(zhi)器(qi)及磷酸鐵鋰 (LiFePO4) 電(dian)(dian)池(chi)(chi)充電(dian)(dian)器(qi) LTC4156，該器(qi)件適用于單節電(dian)(dian)池(chi)(chi)設(she)備，例如(ru)便攜式醫療和工業設(she)備、備份設(she)備以及其他高功(gong)(gong)(gong)(gong)率(lv)(lv)(lv)密度(du)電(dian)(dian)池(chi)(chi)供電(dian)(dian)應用。該 IC 可(ke)高效(xiao)地(di)(di)從各種(zhong)電(dian)(dian)源傳輸(shu)高達 15W 的(de)(de)功(gong)(gong)(gong)(gong)率(lv)(lv)(lv)，同時最大(da)(da)限(xian)度(du)地(di)(di)降低功(gong)(gong)(gong)(gong)耗(hao)并減輕熱量的(de)(de)限(xian)制(zhi)。LTC4156 的(de)(de)開關電(dian)(dian)源通(tong)路拓撲結構可(ke)無(wu)縫地(di)(di)管(guan)理從兩個(ge)輸(shu)入(ru)源 (例如(ru)：一個(ge)墻(qiang)上適配器(qi)和 USB 端口) 至器(qi)件的(de)(de)可(ke)再(zai)充 LiFePO4 電(dian)(dian)池(chi)(chi)的(de)(de)功(gong)(gong)(gong)(gong)率(lv)(lv)(lv)輸(shu)送，并在輸(shu)入(ru)功(gong)(gong)(gong)(gong)率(lv)(lv)(lv)有限(xian)時優先向系統負載供電(dian)(dian)。

因(yin)為 LTC4156 節省了功率，所以(yi)(yi)該器件允許輸(shu)出(chu)負載電(dian)(dian)(dian)(dian)流(liu)超過輸(shu)入電(dian)(dian)(dian)(dian)源吸取(qu)的(de)電(dian)(dian)(dian)(dian)流(liu)，從(cong)而能最大限度(du)地(di)利用(yong)可用(yong)功率給電(dian)(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian)(dian)，而不(bu)會超出(chu)輸(shu)入電(dian)(dian)(dian)(dian)源供(gong)電(dian)(dian)(dian)(dian)規范(fan)的(de)要求(qiu)。例(li)如，當(dang)從(cong)一個 5V/2A 交(jiao)流(liu)適配(pei)器供(gong)電(dian)(dian)(dian)(dian)時(shi)，該 IC 的(de)開關(guan)穩(wen)壓器高效地(di)將(jiang)可用(yong) 10W的(de) 90% 以(yi)(yi)上(shang)之功率傳送(song)出(chu)去，從(cong)而可提供(gong)高達(da) 2.4A 的(de)充電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流(liu)，并實(shi)現較(jiao)快的(de)充電(dian)(dian)(dian)(dian)速度(du)。與普通開關(guan)電(dian)(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian)(dian)器不(bu)同，LTC4156 的(de)特(te)點是即(ji)時(shi)接通工作，以(yi)(yi)確保即(ji)使電(dian)(dian)(dian)(dian)池(chi)已深度(du)放電(dian)(dian)(dian)(dian)，一插(cha)上(shang)電(dian)(dian)(dian)(dian)源插(cha)頭時(shi)就(jiu)有(you)系(xi)統電(dian)(dian)(dian)(dian)源。該器件支(zhi)持 USB OTG (On-The-Go)，因(yin)此無(wu)需任何額外組件，就(jiu)可以(yi)(yi)反過來向 USB 端口提供(gong)一個 5V 電(dian)(dian)(dian)(dian)源。

通過一個簡單的兩線 I2C 端口，可在電路板上調整很多系統控制參數，包括充電電流、輸入電流 (包括 USB 2.0 和 3.0 兼容設置) 和浮置電壓 (3.45V、3.55V、3.60V 和3.80V)。該通信總線也允許 LTC4156 提供狀態信息，例如電池溫度、輸入電源狀態、充電器狀(zhuang)態和(he)故障狀(zhuang)態信息。

LTC4156 的(de)自(zi)主型全(quan)功能(neng)單節 LiFePO4 電池(chi)充(chong)(chong)(chong)電器能(neng)夠(gou)提供高(gao)達 3.5A 的(de)充(chong)(chong)(chong)電電流和(he) 15 種充(chong)(chong)(chong)電電流設定值。該充(chong)(chong)(chong)電器具(ju)備自(zi)動再充(chong)(chong)(chong)電、失效電池(chi)檢測(ce)、可(ke)編程安全(quan)定時器、熱敏電阻(zu)適宜溫度充(chong)(chong)(chong)電、可(ke)編程充(chong)(chong)(chong)電結束(shu)指示(shi) / 終止、以及可(ke)編程中斷發生(sheng)等功能(neng)。

LTC4156 的雙路(lu)輸入、優先級多路(lu)復用(yong)過(guo)壓(ya)保(bao)護 (OVP) 電(dian)(dian)路(lu)可避免因意外施加(jia)高(gao)電(dian)(dian)壓(ya)而造(zao)成的任(ren)何損壞。其理想(xiang)二極管控(kong)制器(qi)可確保(bao)始終能(neng)夠向 VOUT 提供(gong)(gong)足(zu)夠的功率，即使在輸入功率不足(zu)或缺失的情況下也(ye)不例外。為(wei)最大限度地(di)減(jian)少(shao)當(dang)器(qi)件連接至(zhi)一個暫(zan)(zan)停模式(shi) USB 端口時的漏電(dian)(dian)流，由(you)一個布(bu)設在 VBUS 與(yu) VOUT 之間的 LDO 給應用(yong)提供(gong)(gong)可容(rong)許(xu)的暫(zan)(zan)停模式(shi) USB 電(dian)(dian)流。為(wei)了(le)消除從制造(zao)到銷售(shou)過(guo)程(cheng)中(zhong)的電(dian)(dian)池消耗(hao)，一種“裝運及貯(zhu)存”特性可將已(yi)經(jing)很低的電(dian)(dian)池待機(ji)電(dian)(dian)流減(jian)小至(zhi)接近于零(ling)。LTC4156 為(wei) LTC4155 提供(gong)(gong)了(le)補充，后(hou)者(zhe)擁有針(zhen)對鋰(li)離子 / 鋰(li)聚合物電(dian)(dian)池供(gong)(gong)電(dian)(dian)型系統的相同特性集。

LTC4156 采用扁(bian)平 (0.75mm) 28 引腳(jiao) 4mm x 5mm QFN 封裝(zhuang)，保證在(zai) -40°C 至 125°C 的溫度范圍內工作。千片(pian)(pian)批購價為每片(pian)(pian) 4.07 美元。

照片說明：具(ju) OVP 和 USB OTG 的高效率 I2C 電(dian)源(yuan)管理(li)器及 3.5A LiFePO4 電(dian)池充(chong)電(dian)器

性能概要：LTC4156

?大功率、高效率開關型 LiFePO4 電池充電器能(neng)可提供 3.5A 充電電流

?單片開關穩壓器(qi)可對有限的可用輸入(ru)功率之(zhi)利用進(jin)行優化

?雙輸入過壓保護(hu)控制器

?優先級多路復(fu)用適用于多輸入

?I2C/SMBus 控制以實現最佳(jia)系統性(xing)能(neng)并提供狀態信息(xi)

?在電(dian)池(chi)電(dian)量很低時即時接通工(gong)作

?電池理想二極管控(kong)制器以實現電源管理

?從電(dian)池到 USB 端口提供(gong) USB OTG 供(gong)電(dian)

?全功能磷酸鐵(tie)鋰充電(dian)器具 4 種(zhong)浮置電(dian)壓設置 (3.45V、3.55V、3.60V 和 3.80V)

?用交流(liu)適配器提供 3.5A 最大充電電流(liu)

?支持 USB 2.0 和 USB 3.0 規范

?扁平 (0.75mm) 28 引線 4mm x 5mm QFN 封裝(zhuang)