1.6A動態電池充電器/電源管理芯片
為移動消費電子產品提供電源管理半導體器件的開發商Analogictech有限公司(納斯達克: AATI)日前宣布,推出一款產品編號為AAT3670的高度集成1.6A動態電池充電器與電源管理芯片。該款高度智能型器件將一個電池充電器、限流(liu)負載開關電(dian)(dian)路(lu)及(ji)控制電(dian)(dian)路(lu)集成于一體,適用于由單(dan)塊(kuai)鋰離子/聚合物(wu)電(dian)(dian)池供電(dian)(dian)的便攜式系統(tong)(tong),并在不損(sun)害電(dian)(dian)池的充電(dian)(dian)壽命周期以(yi)及(ji)無需添(tian)加(jia)外置負載開關的情況下(xia),允許使用者在通過一個AC適配器或(huo)USB端(duan)口(kou)給電(dian)(dian)池充電(dian)(dian)同時,運行他們的系統(tong)(tong)。AAT3670可(ke)向電(dian)(dian)池提供盡(jin)可(ke)能最高的充電(dian)(dian)電(dian)(dian)流(liu),從而能夠讓消費者以(yi)盡(jin)可(ke)能最短的充電(dian)(dian)時間(jian)來完成充電(dian)(dian)。
“便(bian)攜式(shi)系統(tong)設(she)計師想要在系統(tong)運行的(de)同時,保(bao)證電(dian)(dian)池在最(zui)(zui)大的(de)有用(yong)電(dian)(dian)流(liu)下充(chong)電(dian)(dian),他們必須將(jiang)此功(gong)能(neng)特性設(she)法設(she)計進(jin)帶有單立元(yuan)件的(de)系統(tong)內(nei)。”AnalogicTech產品線主管Bill Weiss說。“AAT3670通過連續監控系統(tong)運行當(dang)中的(de)功(gong)率需求,據此自(zi)動(dong)調(diao)節充(chong)電(dian)(dian)電(dian)(dian)流(liu),這樣就為電(dian)(dian)池提供了(le)盡可能(neng)最(zui)(zui)高(gao)的(de)充(chong)電(dian)(dian)電(dian)(dian)流(liu),并因此使電(dian)(dian)池充(chong)電(dian)(dian)時間最(zui)(zui)短化。另(ling)外(wai),它還減少了(le)元(yuan)器件的(de)使用(yong)數量,降低了(le)原料成本(ben)(BOM),并縮(suo)小了(le)印刷電(dian)(dian)路(lu)板(PCB)的(de)尺寸。”
動態供電電源
AAT3670通(tong)過在電(dian)源(yuan)(yuan)、電(dian)池和系(xi)統(tong)之間(jian)同時進行功率的(de)分(fen)配(pei)(pei)管理,可(ke)為系(xi)統(tong)負載提(ti)供動態的(de)供電(dian)電(dian)源(yuan)(yuan)。如果系(xi)統(tong)負載電(dian)流大于來自AC適(shi)配(pei)(pei)器或USB端口可(ke)提(ti)供的(de)輸入電(dian)源(yuan)(yuan)電(dian)流,AAT3670可(ke)以(yi)從(cong)電(dian)池中供應額(e)外所(suo)需。
一個(ge)電(dian)(dian)(dian)壓感應電(dian)(dian)(dian)荷抑制回(hui)路(voltage-sensing charge reducTIon loop)對(dui)AC適(shi)配器和USB的輸(shu)入電(dian)(dian)(dian)壓進行監控,并且根據系(xi)統(tong)負載電(dian)(dian)(dian)流所(suo)需多少,對(dui)電(dian)(dian)(dian)池的充電(dian)(dian)(dian)電(dian)(dian)(dian)流進行阻截,從而自(zi)動防止電(dian)(dian)(dian)壓下跌。此功能僅(jin)通(tong)過自(zi)動調(diao)節(jie)充電(dian)(dian)(dian)電(dian)(dian)(dian)流到某一限(xian)度就能保持輸(shu)入源電(dian)(dian)(dian)壓的完整性,同時還(huan)確保了系(xi)統(tong)的連續運行,并用最短的時間對(dui)電(dian)(dian)(dian)池進行充電(dian)(dian)(dian)。
在重負載狀態下,芯片的內部溫度有可能升高(根據PCB的具體設計情況)。傳統的熱保護電路只是簡單地將熱源關閉。由于AAT3670可向系統提供工作電源,這樣的關閉會被認為是一個故障狀況,所以是不能被允許的。因此,AAT3670內置一個數字熱控回路,它可以測量內部晶圓片的溫度,還可以在晶圓片溫度超出極限值時,降低充電電流。由于不關閉電池充電器,此數字熱控回路會根據一系列的運行狀況,將(jiang)充電(dian)電(dian)流保(bao)持最大。
對使用AC適配器進(jin)行充(chong)(chong)電(dian)(dian)時,AAT3670所提供的電(dian)(dian)池充(chong)(chong)電(dian)(dian)電(dian)(dian)流可(ke)(ke)以調(diao)到1.6A;對使用USB高(gao)電(dian)(dian)壓(ya)充(chong)(chong)電(dian)(dian),可(ke)(ke)調(diao)到0.9A;對使用USB低電(dian)(dian)壓(ya)充(chong)(chong)電(dian)(dian),可(ke)(ke)調(diao)到0.1A。低的“電(dian)(dian)池到系統”(battery-to-system)阻抗可(ke)(ke)以將(jiang)功(gong)耗(hao)和電(dian)(dian)壓(ya)余(yu)量(voltage headroom)保持最小(xiao)。
AAT3670可監控電池在各種故障狀態下的溫度和充電狀況,這些故障包括過電壓、短路和超溫。在故障發生時,充電器能夠自動關閉(bi)以保護充(chong)電(dian)設備、控制系統(tong)和(he)電(dian)池。一個電(dian)池充(chong)電(dian)器的計(ji)時(shi)器同樣可以在超出用戶(hu)所設置的充(chong)電(dian)時(shi)長的情況下終止(zhi)充(chong)電(dian),從而(er)保護了電(dian)池和(he)系統(tong)。兩個狀態監控輸出引(yin)腳(jiao)可通過外接的LED(發光二極管)來指示電(dian)池充(chong)電(dian)狀態。
