“多功(gong)能化(hua)”、“小(xiao)型(xing)化(hua)”、“高密度(du)化(hua)”等(deng)(deng)成為(wei)了當今(jin)半(ban)導(dao)體器件(jian)的代表(biao)(biao)關鍵詞，尤(you)其是在汽(qi)車(che)(che)電(dian)(dian)(dian)子(zi)控制系(xi)統應用(yong)中(zhong)，表(biao)(biao)現地(di)淋漓盡致。眾所知周，汽(qi)車(che)(che)電(dian)(dian)(dian)子(zi)系(xi)統中(zhong)的半(ban)導(dao)體器件(jian)極其容易受到(dao)多種(zhong)瞬態(tai)浪(lang)涌(yong)的干擾、威脅。為(wei)此(ci)，汽(qi)車(che)(che)電(dian)(dian)(dian)子(zi)瞬態(tai)浪(lang)涌(yong)防護(hu)方(fang)案(an)設(she)計(ji)，是電(dian)(dian)(dian)子(zi)工程師(shi)必做的功(gong)課之一。TVS二(er)極管廠家東(dong)(dong)沃(wo)(wo)電(dian)(dian)(dian)子(zi)DOWOSEMI在汽(qi)車(che)(che)電(dian)(dian)(dian)子(zi)瞬態(tai)浪(lang)涌(yong)防護(hu)領域有十余年的實(shi)戰經(jing)驗(yan)，經(jing)常有從事車(che)(che)載電(dian)(dian)(dian)子(zi)產品的廠家向東(dong)(dong)沃(wo)(wo)電(dian)(dian)(dian)子(zi)FAE工程師(shi)尋(xun)求幫助，保(bao)護(hu)方(fang)案(an)設(she)計(ji)、電(dian)(dian)(dian)路保(bao)護(hu)元件(jian)選型(xing)、EMC測試(shi)、樣品申請等(deng)(deng)等(deng)(deng)。

從事汽車(che)(che)電(dian)(dian)(dian)(dian)子(zi)EMC的電(dian)(dian)(dian)(dian)子(zi)工(gong)程師都知道，ISO 7637-2和ISO 10605是(shi)汽車(che)(che)電(dian)(dian)(dian)(dian)子(zi)里面電(dian)(dian)(dian)(dian)氣抗擾(rao)度遇到(dao)的最重要標準(zhun)(zhun)體系。ISO 7637-2電(dian)(dian)(dian)(dian)源線瞬態傳導干擾(rao)抗擾(rao)性試驗(yan)，有8種(zhong)脈沖波(bo)形：波(bo)形1、2a、2b、3a、3b、4、5a、5b，在(zai)這八種(zhong)脈沖波(bo)形中，其中5a、5b相對來(lai)說，屬于能量比較大的脈沖，不(bu)但(dan)考驗(yan)了汽車(che)(che)電(dian)(dian)(dian)(dian)子(zi)產品(pin)的抗干擾(rao)能力，而(er)且還檢(jian)驗(yan)了設(she)備元器件的抗破(po)壞性。ISO 10605標準(zhun)(zhun)規定了車(che)(che)輛(liang)電(dian)(dian)(dian)(dian)子(zi)電(dian)(dian)(dian)(dian)氣設(she)備在(zai)裝配(pei)、維修過程中及(ji)駕駛人員在(zai)車(che)(che)內外可能產生的靜(jing)電(dian)(dian)(dian)(dian)放(fang)電(dian)(dian)(dian)(dian)耐受性能的試驗(yan)方法，以(yi)此來(lai)檢(jian)測電(dian)(dian)(dian)(dian)子(zi)電(dian)(dian)(dian)(dian)氣設(she)備在(zai)受到(dao)靜(jing)電(dian)(dian)(dian)(dian)放(fang)電(dian)(dian)(dian)(dian)時能否正常工(gong)作(zuo)。

汽(qi)車(che)電(dian)(dian)子電(dian)(dian)壓分為兩(liang)類，小車(che)電(dian)(dian)壓基本上(shang)都是(shi)(shi)12V的(de)，大(da)(da)車(che)（大(da)(da)巴、卡車(che)等等）一般(ban)都是(shi)(shi)在(zai)24V，當然現(xian)在(zai)的(de)電(dian)(dian)動汽(qi)車(che)也有48V。但是(shi)(shi)，目前市(shi)面上(shang)主(zhu)流的(de)還是(shi)(shi)12V系(xi)(xi)(xi)統(tong)和24V系(xi)(xi)(xi)統(tong)。12V系(xi)(xi)(xi)統(tong)的(de)電(dian)(dian)源芯片(pian)一般(ban)承受40V的(de)電(dian)(dian)壓，過(guo)電(dian)(dian)壓防(fang)浪涌(yong)防(fang)護器件選用24V大(da)(da)功(gong)率TVS瞬態抑制二極管，24V系(xi)(xi)(xi)統(tong)則(ze)選用36V的(de)大(da)(da)功(gong)率TVS二極管。一般(ban)來說，推薦汽(qi)車(che)電(dian)(dian)子客戶選用：

1）12V系統：5.0SMDJ22A、SM5S22A、SM8S24A、SM5S24A、5.0SMDJ24A、5.0SMDJ24CA、SM5S24A、SM6S22A、SM6S24A、SM8T24A、SMCJ24A、SMCJ24CA、SMDJ24A、SMDJ24CA、SM5S24CA；

2）24V系統：SM5S36A、SM5S33A、SM6S36A、SM8S33A、SM6S33A、SM8T33A；

不同的保護需求和測試條件，汽車電子瞬態浪涌保護用TVS二極管型號也不一樣的，具體方案設計、電路保護元件選型可與東沃FAE工程師溝通交流！