我(wo)們都知(zhi)道PD快充要比普通(tong)的(de)充電器(qi)充電速(su)度快上(shang)許多，但是卻很少有人知(zhi)道為什么(me)PD電源適(shi)配器(qi)可(ke)以充的(de)更快，PD電源適(shi)配器(qi)的(de)工(gong)作(zuo)原理是什么(me)，今天小編就用(yong)比較通(tong)俗的(de)方法來告訴大家PD電源適(shi)配器(qi)是如何進行(xing)快充的(de)。

首先當PD電(dian)(dian)源適(shi)(shi)配(pei)器和充(chong)電(dian)(dian)設(she)備(bei)連(lian)接以后。會通過CC線告訴充(chong)電(dian)(dian)設(she)備(bei)，電(dian)(dian)源適(shi)(shi)配(pei)器能夠提供(gong)多(duo)少種電(dian)(dian)壓，以及對應(ying)的電(dian)(dian)流。然后用電(dian)(dian)設(she)備(bei)在了(le)解了(le)PD電(dian)(dian)源適(shi)(shi)配(pei)器的供(gong)電(dian)(dian)能力以后，會從中選擇(ze)一個最合適(shi)(shi)自己的供(gong)電(dian)(dian)方式，并向適(shi)(shi)配(pei)器請(qing)求數據包。這里要注意(yi)，如果PD電(dian)(dian)源適(shi)(shi)配(pei)器無法提供(gong)用電(dian)(dian)設(she)備(bei)支(zhi)持的電(dian)(dian)壓，那(nei)么就無法進(jin)行(xing)PD快充(chong)。所以在選擇(ze)PD電(dian)(dian)源適(shi)(shi)配(pei)器時，支(zhi)持電(dian)(dian)壓檔數越多(duo)越好(hao)。

PD電(dian)(dian)(dian)源適配器(qi)在了解了用電(dian)(dian)(dian)設備(bei)的選擇(ze)以(yi)后，會(hui)評(ping)估(gu)自身(shen)的能力，然后發(fa)送“接(jie)受”的命令，然后進(jin)行(xing)(xing)內部的電(dian)(dian)(dian)壓(ya)變換，并(bing)向用電(dian)(dian)(dian)設備(bei)發(fa)送“電(dian)(dian)(dian)源準備(bei)好”數據(ju)包。接(jie)下來就(jiu)向VBUS施加協商后的新的供電(dian)(dian)(dian)電(dian)(dian)(dian)壓(ya)。如果僅僅是(shi)進(jin)行(xing)(xing)供電(dian)(dian)(dian)的話，那(nei)么PD到(dao)此就(jiu)算完成了任務，這就(jiu)是(shi)所謂的PD握手協議。

這里需要注意的是(shi)只(zhi)有(you)當用電(dian)設備和充(chong)電(dian)器雙方都(dou)支(zhi)持PD協議(yi)時，才(cai)有(you)可能進行(xing)快充(chong)，而(er)且還(huan)需要雙方的電(dian)壓(ya)和電(dian)流能夠匹配成功，現(xian)在，你明白了嗎？