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(zai)(zai)開(kai)關電(dian)(dian)(dian)路及控制(zhi)電(dian)(dian)(dian)路集成于一(yi)體,適用于由單塊鋰離子(zi)/聚合物電(dian)(dian)(dian)池(chi)供電(dian)(dian)(dian)的(de)便(bian)攜(xie)式系統,并在不損(sun)害電(dian)(dian)(dian)池(chi)的(de)充(chong)(chong)電(dian)(dian)(dian)壽命周(zhou)期以及無需添加外置(zhi)負載(zai)(zai)開(kai)關的(de)情況下,允許使用者在通過一(yi)個AC適配器(qi)或USB端(duan)口給電(dian)(dian)(dian)池(chi)充(chong)(chong)電(dian)(dian)(dian)同時,運(yun)行(xing)他們的(de)系統。AAT3670可向電(dian)(dian)(dian)池(chi)提供盡可能(neng)最(zui)高的(de)充(chong)(chong)電(dian)(dian)(dian)電(dian)(dian)(dian)流(liu),從而(er)能(neng)夠讓消費者以盡可能(neng)最(zui)短(duan)的(de)充(chong)(chong)電(dian)(dian)(dian)時間來完成充(chong)(chong)電(dian)(dian)(dian)。
“便(bian)攜式系(xi)統(tong)(tong)設(she)(she)計(ji)師(shi)想(xiang)要在系(xi)統(tong)(tong)運(yun)行(xing)的(de)(de)同時(shi),保證電(dian)池在最(zui)大的(de)(de)有(you)用電(dian)流下(xia)充電(dian),他們必須將此功(gong)能特性設(she)(she)法設(she)(she)計(ji)進帶有(you)單立(li)元(yuan)(yuan)件的(de)(de)系(xi)統(tong)(tong)內。”AnalogicTech產品線(xian)主管(guan)Bill Weiss說。“AAT3670通過連續監(jian)控系(xi)統(tong)(tong)運(yun)行(xing)當(dang)中的(de)(de)功(gong)率需求(qiu),據此自動調節(jie)充電(dian)電(dian)流,這樣就為電(dian)池提供了(le)盡可能最(zui)高的(de)(de)充電(dian)電(dian)流,并因此使電(dian)池充電(dian)時(shi)間最(zui)短(duan)化。另外,它還(huan)減少了(le)元(yuan)(yuan)器件的(de)(de)使用數量,降低了(le)原料成本(ben)(BOM),并縮小(xiao)了(le)印刷電(dian)路(lu)板(PCB)的(de)(de)尺寸(cun)。”
動態供電電源
AAT3670通過在電(dian)源(yuan)、電(dian)池(chi)和(he)系統之間同時(shi)進行功率(lv)的分(fen)配管理,可(ke)為系統負載提供(gong)(gong)動態的供(gong)(gong)電(dian)電(dian)源(yuan)。如果系統負載電(dian)流大于來自AC適配器或USB端口可(ke)提供(gong)(gong)的輸入電(dian)源(yuan)電(dian)流,AAT3670可(ke)以從(cong)電(dian)池(chi)中供(gong)(gong)應(ying)額(e)外(wai)所需。
一個電壓感應電荷抑制回路(voltage-sensing charge reducTIon loop)對(dui)AC適配器和(he)USB的(de)(de)輸(shu)入(ru)(ru)電壓進(jin)行(xing)(xing)監控(kong),并(bing)且根據系(xi)(xi)統負載電流所需多少,對(dui)電池的(de)(de)充(chong)電電流進(jin)行(xing)(xing)阻(zu)截,從而自動防止電壓下跌。此功能(neng)僅通過自動調節充(chong)電電流到某(mou)一限度就能(neng)保持輸(shu)入(ru)(ru)源電壓的(de)(de)完整性,同時(shi)還確保了系(xi)(xi)統的(de)(de)連(lian)續運行(xing)(xing),并(bing)用最短(duan)的(de)(de)時(shi)間對(dui)電池進(jin)行(xing)(xing)充(chong)電。
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(shu)字熱控回路(lu)會根據(ju)一(yi)系(xi)列的運行狀況,將充(chong)電(dian)電(dian)流保持最(zui)大。
對(dui)使用(yong)(yong)AC適配(pei)器進(jin)行充(chong)電時,AAT3670所提供的電池充(chong)電電流可(ke)以調到1.6A;對(dui)使用(yong)(yong)USB高(gao)電壓充(chong)電,可(ke)調到0.9A;對(dui)使用(yong)(yong)USB低(di)電壓充(chong)電,可(ke)調到0.1A。低(di)的“電池到系統”(battery-to-system)阻抗可(ke)以將功耗和電壓余量(voltage headroom)保持(chi)最(zui)小。
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(gou)自動關(guan)閉以保(bao)護(hu)充(chong)電(dian)(dian)(dian)設備、控制系(xi)統(tong)和(he)電(dian)(dian)(dian)池(chi)。一個(ge)電(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)器的計(ji)時器同樣(yang)可以在超出用戶所設置(zhi)的充(chong)電(dian)(dian)(dian)時長的情(qing)況下(xia)終止充(chong)電(dian)(dian)(dian),從而(er)保(bao)護(hu)了電(dian)(dian)(dian)池(chi)和(he)系(xi)統(tong)。兩個(ge)狀態監控輸出引腳可通(tong)過外接(jie)的LED(發光二(er)極管)來指示電(dian)(dian)(dian)池(chi)充(chong)電(dian)(dian)(dian)狀態。