開關電源(yuan)模塊阻(zu)(zu)抗(kang)(kang)是指內部電(dian)(dian)(dian)(dian)阻(zu)(zu)、電(dian)(dian)(dian)(dian)容(rong)(rong)和(he)電(dian)(dian)(dian)(dian)感(gan)組成的電(dian)(dian)(dian)(dian)路(lu)(lu)對交(jiao)(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)起到阻(zu)(zu)礙(ai)作用(yong)。電(dian)(dian)(dian)(dian)阻(zu)(zu)的阻(zu)(zu)抗(kang)(kang)就(jiu)是其(qi)本身，電(dian)(dian)(dian)(dian)容(rong)(rong)電(dian)(dian)(dian)(dian)感(gan)兩者對交(jiao)(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)的阻(zu)(zu)礙(ai)叫電(dian)(dian)(dian)(dian)抗(kang)(kang)。電(dian)(dian)(dian)(dian)容(rong)(rong)在電(dian)(dian)(dian)(dian)路(lu)(lu)中對交(jiao)(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)阻(zu)(zu)礙(ai)叫容(rong)(rong)抗(kang)(kang)，交(jiao)(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)頻(pin)率越大，容(rong)(rong)抗(kang)(kang)越小，有隔直通交(jiao)(jiao)(jiao)的作用(yong)。電(dian)(dian)(dian)(dian)感(gan)在電(dian)(dian)(dian)(dian)路(lu)(lu)中對交(jiao)(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)阻(zu)(zu)礙(ai)叫感(gan)抗(kang)(kang)，交(jiao)(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)頻(pin)率越大，感(gan)抗(kang)(kang)就(jiu)越大，有對交(jiao)(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)通直隔交(jiao)(jiao)(jiao)的作用(yong)，可進行濾波。
　　電(dian)(dian)源模塊內阻(zu)較大會不利于負(fu)載穩壓(ya)電(dian)(dian)路工(gong)作(zuo)，嚴重的(de)(de)(de)負(fu)載電(dian)(dian)流(liu)任何(he)變(bian)化都會導致(zhi)模塊輸(shu)出(chu)的(de)(de)(de)起伏(fu)，起伏(fu)對(dui)(dui)測試的(de)(de)(de)影(ying)響和(he)脈沖與噪聲對(dui)(dui)測試結果(guo)的(de)(de)(de)影(ying)響一樣。當(dang)線電(dian)(dian)壓(ya)或(huo)負(fu)載電(dian)(dian)流(liu)變(bian)化時(shi)(shi)，直流(liu)電(dian)(dian)源模塊的(de)(de)(de)輸(shu)出(chu)電(dian)(dian)壓(ya)會有所起伏(fu)。穩壓(ya)程度(du)由(you)穩壓(ya)電(dian)(dian)路的(de)(de)(de)參數，濾波電(dian)(dian)容(rong)容(rong)量和(he)能(neng)量釋(shi)放的(de)(de)(de)速(su)率所決定，穩定大小(xiao)是空(kong)載或(huo)滿載時(shi)(shi)輸(shu)出(chu)電(dian)(dian)壓(ya)的(de)(de)(de)百分比或(huo)變(bian)化值。
　　瞬態響應或恢(hui)復(fu)時(shi)(shi)間一(yi)般在負(fu)載變(bian)化(hua)10%時(shi)(shi)，常(chang)用(yong)輸(shu)(shu)出偏(pian)離(li)(li)峰(feng)值電(dian)壓(ya)的(de)(de)毫伏(fu)數標定輸(shu)(shu)出偏(pian)離(li)(li)量，用(yong)輸(shu)(shu)出恢(hui)復(fu)到(dao)正常(chang)值所(suo)用(yong)毫伏(fu)數標出恢(hui)復(fu)時(shi)(shi)間。電(dian)源(yuan)模塊瞬態響應和恢(hui)復(fu)時(shi)(shi)間的(de)(de)大(da)(da)小表明輸(shu)(shu)出負(fu)載在突然(ran)變(bian)化(hua)時(shi)(shi)，穩壓(ya)電(dian)路(lu)恢(hui)復(fu)正常(chang)電(dian)壓(ya)能力的(de)(de)大(da)(da)小，一(yi)般是用(yong)當負(fu)載突然(ran)發生變(bian)化(hua)時(shi)(shi)輸(shu)(shu)出的(de)(de)偏(pian)離(li)(li)值或是輸(shu)(shu)出恢(hui)復(fu)到(dao)原(yuan)來(lai)值所(suo)用(yong)的(de)(de)時(shi)(shi)間來(lai)標定。

　　阻(zu)抗(kang)(kang)匹配可以(yi)調整負載(zai)功率和抑制信號(hao)反射(she)，信號(hao)源(yuan)或(huo)傳輸線跟負載(zai)間(jian)達到合(he)適搭(da)配叫做(zuo)阻(zu)抗(kang)(kang)匹配。對于一個純電(dian)(dian)阻(zu)電(dian)(dian)路(lu)或(huo)低頻(pin)電(dian)(dian)路(lu)，電(dian)(dian)容電(dian)(dian)感的電(dian)(dian)抗(kang)(kang)值基本可以(yi)忽略，電(dian)(dian)路(lu)阻(zu)抗(kang)(kang)主(zhu)要來源(yuan)電(dian)(dian)阻(zu)。

　　在高(gao)(gao)頻(pin)領域(yu)中，當信(xin)(xin)號波長和傳輸線長處于(yu)相(xiang)同量級時，反射(she)信(xin)(xin)號易與(yu)原信(xin)(xin)號混疊，而阻(zu)(zu)(zu)抗匹配可以有效減少消除高(gao)(gao)頻(pin)信(xin)(xin)號反射(she)。PCB走(zou)線阻(zu)(zu)(zu)抗主要(yao)來自寄生(sheng)電容、電感、電阻(zu)(zu)(zu)，因素(su)有材料介電常(chang)數(shu)、線寬(kuan)、線厚和焊盤(pan)的厚度等(deng)。高(gao)(gao)頻(pin)領域(yu)中信(xin)(xin)號頻(pin)率(lv)對PCB走(zou)線的阻(zu)(zu)(zu)抗值影(ying)響很大，當數(shu)字信(xin)(xin)號邊沿時間小于(yu)1ns或模擬信(xin)(xin)號頻(pin)率(lv)超過300M就要(yao)考慮阻(zu)(zu)(zu)抗問(wen)題。
　　目前阻(zu)(zu)抗匹(pi)配(pei)的(de)(de)方(fang)法主要有(you)改(gai)變(bian)阻(zu)(zu)抗力(li)或(huo)調整傳輸線兩種。改(gai)變(bian)阻(zu)(zu)抗力(li)是指通過電容(rong)、電感(gan)與負(fu)載(zai)的(de)(de)串聯并聯調整負(fu)載(zai)阻(zu)(zu)抗值(zhi)，達到源和負(fu)載(zai)阻(zu)(zu)抗匹(pi)配(pei)。調整傳輸線是加長源和負(fu)載(zai)間的(de)(de)距離，配(pei)合電容(rong)電感(gan)把阻(zu)(zu)抗力(li)調為零。
　　開關(guan)電(dian)源目標(biao)阻抗(kang)是電(dian)源系統(tong)的(de)瞬態(tai)阻抗(kang)，和一定寬度的(de)頻(pin)段(duan)有(you)關(guan)，在(zai)相同條件下，電(dian)源系統(tong)的(de)頻(pin)率越大(da)，其阻抗(kang)越大(da)。