凌力爾(er)特公(gong)司(si) (Linear Technology Corporation) 推出(chu)大功率(lv)、I2C 控制和高(gao)效(xiao)率(lv)的電(dian)(dian)源(yuan)通(tong)路 (PowerPath?) 管理(li)(li)器、理(li)(li)想二極管控制器及(ji)磷(lin)酸鐵鋰 (LiFePO4) 電(dian)(dian)池充電(dian)(dian)器 LTC4156，該器件(jian)適(shi)用(yong)于單節電(dian)(dian)池設備，例如便攜式(shi)醫療(liao)和工業設備、備份設備以及(ji)其他(ta)高(gao)功率(lv)密度電(dian)(dian)池供電(dian)(dian)應用(yong)。該 IC 可(ke)高(gao)效(xiao)地從各(ge)種(zhong)電(dian)(dian)源(yuan)傳輸(shu)高(gao)達 15W 的功率(lv)，同(tong)時最大限(xian)度地降低功耗(hao)并減輕熱量的限(xian)制。LTC4156 的開關電(dian)(dian)源(yuan)通(tong)路拓撲(pu)結構可(ke)無縫地管理(li)(li)從兩個輸(shu)入源(yuan) (例如：一(yi)個墻(qiang)上(shang)適(shi)配器和 USB 端口) 至器件(jian)的可(ke)再充 LiFePO4 電(dian)(dian)池的功率(lv)輸(shu)送，并在輸(shu)入功率(lv)有限(xian)時優先向(xiang)系(xi)統負載供電(dian)(dian)。

因(yin)為 LTC4156 節(jie)省了功(gong)(gong)率，所以該(gai)器(qi)件(jian)允許輸(shu)(shu)出負載電(dian)(dian)流超(chao)過輸(shu)(shu)入電(dian)(dian)源吸取的(de)電(dian)(dian)流，從(cong)而(er)能最大限度(du)(du)(du)地利用(yong)可用(yong)功(gong)(gong)率給電(dian)(dian)池充電(dian)(dian)，而(er)不會超(chao)出輸(shu)(shu)入電(dian)(dian)源供(gong)(gong)(gong)電(dian)(dian)規范的(de)要求(qiu)。例如，當從(cong)一(yi)(yi)個(ge)(ge) 5V/2A 交流適配器(qi)供(gong)(gong)(gong)電(dian)(dian)時，該(gai) IC 的(de)開關(guan)穩壓器(qi)高(gao)效地將(jiang)可用(yong) 10W的(de) 90% 以上(shang)之功(gong)(gong)率傳送出去，從(cong)而(er)可提供(gong)(gong)(gong)高(gao)達 2.4A 的(de)充電(dian)(dian)電(dian)(dian)流，并(bing)實(shi)現較(jiao)快(kuai)的(de)充電(dian)(dian)速(su)度(du)(du)(du)。與普(pu)通開關(guan)電(dian)(dian)池充電(dian)(dian)器(qi)不同(tong)，LTC4156 的(de)特點是即(ji)時接通工作，以確保即(ji)使電(dian)(dian)池已深度(du)(du)(du)放電(dian)(dian)，一(yi)(yi)插(cha)上(shang)電(dian)(dian)源插(cha)頭時就有系統電(dian)(dian)源。該(gai)器(qi)件(jian)支(zhi)持 USB OTG (On-The-Go)，因(yin)此無(wu)需任何(he)額外組件(jian)，就可以反過來向 USB 端口提供(gong)(gong)(gong)一(yi)(yi)個(ge)(ge) 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、充電器狀態和故障狀態信息。

LTC4156 的自主型全功(gong)能單節 LiFePO4 電(dian)(dian)(dian)(dian)(dian)池(chi)充電(dian)(dian)(dian)(dian)(dian)器能夠提供高達 3.5A 的充電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流和 15 種充電(dian)(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)(dian)流設定值。該充電(dian)(dian)(dian)(dian)(dian)器具備自動再(zai)充電(dian)(dian)(dian)(dian)(dian)、失效電(dian)(dian)(dian)(dian)(dian)池(chi)檢測、可(ke)(ke)編程安(an)全定時(shi)器、熱敏電(dian)(dian)(dian)(dian)(dian)阻(zu)適宜溫度(du)充電(dian)(dian)(dian)(dian)(dian)、可(ke)(ke)編程充電(dian)(dian)(dian)(dian)(dian)結束指示 / 終止、以(yi)及可(ke)(ke)編程中(zhong)斷發(fa)生等功(gong)能。

LTC4156 的(de)(de)雙路輸(shu)入、優先(xian)級多路復用(yong)過壓保護 (OVP) 電(dian)(dian)(dian)路可(ke)(ke)避免因意外施(shi)加高電(dian)(dian)(dian)壓而造成的(de)(de)任何損壞。其(qi)理(li)想二極管控(kong)制器可(ke)(ke)確保始終(zhong)能夠向(xiang) VOUT 提供足夠的(de)(de)功(gong)率，即使在(zai)輸(shu)入功(gong)率不(bu)足或缺失的(de)(de)情況下也不(bu)例(li)外。為(wei)最(zui)大限度地(di)減少當器件連接(jie)至一個暫停模式 USB 端口時的(de)(de)漏(lou)電(dian)(dian)(dian)流(liu)(liu)(liu)，由一個布設在(zai) VBUS 與 VOUT 之間的(de)(de) LDO 給應用(yong)提供可(ke)(ke)容許的(de)(de)暫停模式 USB 電(dian)(dian)(dian)流(liu)(liu)(liu)。為(wei)了消(xiao)除從制造到銷售(shou)過程(cheng)中的(de)(de)電(dian)(dian)(dian)池(chi)消(xiao)耗，一種“裝運及貯存”特(te)(te)性可(ke)(ke)將已經很低的(de)(de)電(dian)(dian)(dian)池(chi)待機電(dian)(dian)(dian)流(liu)(liu)(liu)減小至接(jie)近于零。LTC4156 為(wei) LTC4155 提供了補充，后者(zhe)擁有針對鋰(li)(li)離子 / 鋰(li)(li)聚合物電(dian)(dian)(dian)池(chi)供電(dian)(dian)(dian)型系統(tong)的(de)(de)相同特(te)(te)性集。

LTC4156 采用扁平 (0.75mm) 28 引腳(jiao) 4mm x 5mm QFN 封裝，保證(zheng)在 -40°C 至 125°C 的溫度(du)范圍(wei)內工作。千片批購價為(wei)每片 4.07 美元(yuan)。

照(zhao)片說明(ming)：具 OVP 和 USB OTG 的高效率 I2C 電源管理器及(ji) 3.5A LiFePO4 電池充(chong)電器

性(xing)能概要：LTC4156

?大功率、高效率開關型 LiFePO4 電池充電器能可提(ti)供 3.5A 充電(dian)電(dian)流(liu)

?單片(pian)開關穩壓(ya)器可對有限的可用輸入功率(lv)之利用進行(xing)優化

?雙輸入過(guo)壓保護(hu)控制器(qi)

?優先級多路復用適用于多輸入

?I2C/SMBus 控制以實現最佳系統性能并(bing)提供狀態信息

?在電池電量很(hen)低時即時接通工(gong)作(zuo)

?電池理想二(er)極管控(kong)制器以(yi)實(shi)現電源管理

?從(cong)電池到 USB 端口(kou)提供(gong) USB OTG 供(gong)電

?全功能(neng)磷(lin)酸鐵鋰充電器具 4 種浮置(zhi)電壓設置(zhi) (3.45V、3.55V、3.60V 和(he) 3.80V)

?用交流適(shi)配(pei)器提(ti)供 3.5A 最大充電電流

?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