凌力爾特公司 (Linear Technology Corporation) 推(tui)出大(da)功(gong)率、I2C 控制(zhi)(zhi)和(he)高(gao)效率的(de)(de)電(dian)(dian)(dian)源通路 (PowerPath?) 管理器(qi)(qi)、理想二極管控制(zhi)(zhi)器(qi)(qi)及(ji)磷酸(suan)鐵鋰 (LiFePO4) 電(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)器(qi)(qi) LTC4156，該器(qi)(qi)件適(shi)用于(yu)單節(jie)電(dian)(dian)(dian)池(chi)設備(bei)，例(li)如便攜式醫療(liao)和(he)工業設備(bei)、備(bei)份設備(bei)以(yi)及(ji)其他高(gao)功(gong)率密度(du)電(dian)(dian)(dian)池(chi)供電(dian)(dian)(dian)應用。該 IC 可(ke)高(gao)效地(di)(di)從(cong)各種(zhong)電(dian)(dian)(dian)源傳輸(shu)高(gao)達(da) 15W 的(de)(de)功(gong)率，同時最大(da)限度(du)地(di)(di)降(jiang)低功(gong)耗并減(jian)輕熱量的(de)(de)限制(zhi)(zhi)。LTC4156 的(de)(de)開關電(dian)(dian)(dian)源通路拓撲(pu)結(jie)構可(ke)無縫地(di)(di)管理從(cong)兩個輸(shu)入源 (例(li)如：一個墻上適(shi)配器(qi)(qi)和(he) USB 端口) 至器(qi)(qi)件的(de)(de)可(ke)再充(chong) LiFePO4 電(dian)(dian)(dian)池(chi)的(de)(de)功(gong)率輸(shu)送，并在輸(shu)入功(gong)率有限時優(you)先向系統負載供電(dian)(dian)(dian)。

因為 LTC4156 節省了功(gong)率，所以(yi)該器(qi)件(jian)允(yun)許輸出(chu)負載電(dian)(dian)流超過(guo)輸入電(dian)(dian)源吸取的(de)(de)電(dian)(dian)流，從而(er)能最大限度(du)地利(li)用(yong)可用(yong)功(gong)率給電(dian)(dian)池充電(dian)(dian)，而(er)不會超出(chu)輸入電(dian)(dian)源供(gong)(gong)電(dian)(dian)規范的(de)(de)要求(qiu)。例如，當從一(yi)個 5V/2A 交流適(shi)配器(qi)供(gong)(gong)電(dian)(dian)時，該 IC 的(de)(de)開關穩(wen)壓器(qi)高效(xiao)地將可用(yong) 10W的(de)(de) 90% 以(yi)上(shang)之(zhi)功(gong)率傳送出(chu)去(qu)，從而(er)可提(ti)供(gong)(gong)高達(da) 2.4A 的(de)(de)充電(dian)(dian)電(dian)(dian)流，并實現較快的(de)(de)充電(dian)(dian)速度(du)。與普通(tong)(tong)開關電(dian)(dian)池充電(dian)(dian)器(qi)不同(tong)，LTC4156 的(de)(de)特點是即時接通(tong)(tong)工作(zuo)，以(yi)確(que)保即使(shi)電(dian)(dian)池已深度(du)放電(dian)(dian)，一(yi)插上(shang)電(dian)(dian)源插頭時就(jiu)有系(xi)統電(dian)(dian)源。該器(qi)件(jian)支持 USB OTG (On-The-Go)，因此(ci)無需任何額外(wai)組件(jian)，就(jiu)可以(yi)反過(guo)來(lai)向 USB 端口(kou)提(ti)供(gong)(gong)一(yi)個 5V 電(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)態和故障(zhang)狀(zhuang)態信息。

LTC4156 的自主型全(quan)功(gong)能(neng)單節 LiFePO4 電(dian)(dian)(dian)池(chi)充(chong)(chong)(chong)電(dian)(dian)(dian)器能(neng)夠提(ti)供高(gao)達 3.5A 的充(chong)(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流和 15 種充(chong)(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流設定值。該充(chong)(chong)(chong)電(dian)(dian)(dian)器具備自動再充(chong)(chong)(chong)電(dian)(dian)(dian)、失效電(dian)(dian)(dian)池(chi)檢測(ce)、可編程安全(quan)定時器、熱敏電(dian)(dian)(dian)阻(zu)適宜溫度充(chong)(chong)(chong)電(dian)(dian)(dian)、可編程充(chong)(chong)(chong)電(dian)(dian)(dian)結(jie)束(shu)指(zhi)示 / 終止、以及(ji)可編程中斷發生等功(gong)能(neng)。

LTC4156 的(de)(de)雙路(lu)(lu)(lu)輸入(ru)、優先級(ji)多路(lu)(lu)(lu)復用(yong)過(guo)壓(ya)保(bao)護(hu) (OVP) 電(dian)路(lu)(lu)(lu)可避免因意外(wai)施加高電(dian)壓(ya)而造成(cheng)的(de)(de)任何損壞。其理想二(er)極管控制器(qi)可確保(bao)始終(zhong)能夠向 VOUT 提供(gong)(gong)足(zu)夠的(de)(de)功率，即使在輸入(ru)功率不足(zu)或(huo)缺失的(de)(de)情況(kuang)下也不例外(wai)。為最大(da)限度(du)地減(jian)少當器(qi)件連接至一個暫停模(mo)式 USB 端口時(shi)的(de)(de)漏電(dian)流，由一個布(bu)設在 VBUS 與 VOUT 之間的(de)(de) LDO 給應用(yong)提供(gong)(gong)可容許的(de)(de)暫停模(mo)式 USB 電(dian)流。為了(le)消除從制造到(dao)銷售過(guo)程中(zhong)的(de)(de)電(dian)池消耗，一種“裝運及貯存”特(te)性可將已經很低的(de)(de)電(dian)池待(dai)機電(dian)流減(jian)小至接近于零。LTC4156 為 LTC4155 提供(gong)(gong)了(le)補(bu)充，后(hou)者擁有針(zhen)對鋰離子 / 鋰聚合物電(dian)池供(gong)(gong)電(dian)型系統(tong)的(de)(de)相同特(te)性集。

LTC4156 采用扁平 (0.75mm) 28 引(yin)腳 4mm x 5mm QFN 封裝，保證在 -40°C 至 125°C 的溫(wen)度范圍內工(gong)作。千(qian)片(pian)批(pi)購價為每片(pian) 4.07 美元。

照片說明：具 OVP 和 USB OTG 的高效率 I2C 電(dian)源(yuan)管理器及(ji) 3.5A LiFePO4 電(dian)池(chi)充電(dian)器

性能概要：LTC4156

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

?單(dan)片(pian)開關穩壓器可對有(you)限的可用輸(shu)入功率之利用進行優化(hua)

?雙輸入(ru)過壓保護(hu)控制(zhi)器

?優先級(ji)多路復用(yong)適用(yong)于多輸入

?I2C/SMBus 控(kong)制以實現最佳(jia)系統性(xing)能并(bing)提(ti)供狀態信息

?在電池電量很低(di)時(shi)即時(shi)接(jie)通(tong)工作

?電池理(li)想二極管控制器(qi)以實現電源管理(li)

?從電池到(dao) USB 端(duan)口提供 USB OTG 供電

?全(quan)功(gong)能磷(lin)酸鐵鋰(li)充電器(qi)具 4 種浮置電壓設置 (3.45V、3.55V、3.60V 和 3.80V)

?用(yong)交流適配器提(ti)供 3.5A 最大充(chong)電電流

?支持 USB 2.0 和 USB 3.0 規范

?扁平 (0.75mm) 28 引(yin)線 4mm x 5mm QFN 封裝