為了(le)支持與主機(ji)設備及其(qi)創新功(gong)能進行超高(gao)速通信的(de)(de)(de)現代(dai)需(xu)求，USB接(jie)口(kou)(kou)技術(shu)(shu)由(you)USB1.1、USB 2.0、USB 3.0、USB 3.1、USB 3.2（Gen 1、Gen 2、Gen 2x2）、USB Type-C發展到到如(ru)今超火的(de)(de)(de)USB 4。盡管新版本的(de)(de)(de)USB接(jie)口(kou)(kou)技術(shu)(shu)能夠滿足更高(gao)數據速率和更高(gao)功(gong)率傳輸(shu)水平的(de)(de)(de)需(xu)求，但是(shi)USB 2.0接(jie)口(kou)(kou)技術(shu)(shu)在(zai)眾多(duo)電子(zi)設備中仍然是(shi)非常受(shou)歡迎的(de)(de)(de)。Universal Serial Bus2.0，簡稱USB2.0，中文：通用(yong)串行總線，是(shi)一種應(ying)用(yong)在(zai)計算機(ji)領(ling)域的(de)(de)(de)接(jie)口(kou)(kou)技術(shu)(shu)。USB2.0接(jie)口(kou)(kou)傳輸(shu)速度快（低速1.5Mbps、全(quan)速12Mbps、高(gao)速480Mbps），支持熱插(cha)拔以及連接(jie)多(duo)個設備的(de)(de)(de)特性，在(zai)遙控器，打印機(ji)，相機(ji)，揚聲器，鍵盤(pan)、鼠標等(deng)各類(lei)外部設備中得到了(le)廣(guang)泛(fan)的(de)(de)(de)應(ying)用(yong)。

USB 2.0 接口配(pei)置

從(cong)圖中可知，USB 2.0具有4線(xian)接(jie)口(kou)，其中VBUS 通過電(dian)(dian)(dian)(dian)(dian)(dian)纜從(cong)主(zhu)機(ji)到(dao)連接(jie)的(de)設備提供5V和(he) 500mA電(dian)(dian)(dian)(dian)(dian)(dian)源，D+和(he)D-引腳(jiao)(jiao)(jiao)負責傳輸(shu)差(cha)(cha)分(fen)數據信號。在(zai)正常工(gong)作條(tiao)件下，這些差(cha)(cha)分(fen)線(xian)路上的(de)電(dian)(dian)(dian)(dian)(dian)(dian)壓可以達到(dao)5V。第四個引腳(jiao)(jiao)(jiao)為GND接(jie)地引腳(jiao)(jiao)(jiao)。由(you)于USB2.0設備要(yao)求隨插即(ji)用(yong)、隨拔即(ji)關，那么在(zai)這個熱(re)插拔過程(cheng)中，產生的(de)靜電(dian)(dian)(dian)(dian)(dian)(dian)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)（ESD）會導致電(dian)(dian)(dian)(dian)(dian)(dian)子系統工(gong)作異常，甚至造成USB2.0連接(jie)端口(kou)后級(ji)設備毀(hui)壞。因此，我們必須保護USB 2.0端口(kou)免受靜電(dian)(dian)(dian)(dian)(dian)(dian)放(fang)電(dian)(dian)(dian)(dian)(dian)(dian)（ESD）的(de)威脅(xie)。接(jie)下來，東沃電(dian)(dian)(dian)(dian)(dian)(dian)子技術從(cong)USB2.0單雙接(jie)口(kou)應用(yong)場景來設計靜電(dian)(dian)(dian)(dian)(dian)(dian)ESD保護方案(an)，為USB2.0接(jie)口(kou)的(de)穩定(ding)性和(he)安全性護航。

一、USB2.0單接口靜(jing)電浪涌保護方案

1）USB 2.0單(dan)接口靜電浪涌保護方案用分立式ESD二極管

從方案圖中(zhong)(zhong)可知，USB2.0供電(dian)(dian)(dian)(dian)(dian)端VBUS選(xuan)用(yong)(yong)ESD二(er)極(ji)管DW05DP-S，工作(zuo)電(dian)(dian)(dian)(dian)(dian)壓(ya)為5V、擊(ji)穿(chuan)電(dian)(dian)(dian)(dian)(dian)壓(ya)5.7V、鉗位(wei)(wei)電(dian)(dian)(dian)(dian)(dian)壓(ya)15V、最大(da)浪(lang)涌(yong)峰(feng)值電(dian)(dian)(dian)(dian)(dian)流可達(da)100A、DFN1610-2L封裝。在高速差(cha)分數據線D+和D-靜電(dian)(dian)(dian)(dian)(dian)保(bao)護中(zhong)(zhong)，東沃技術選(xuan)用(yong)(yong)DW05DLC-B-S，工作(zuo)電(dian)(dian)(dian)(dian)(dian)壓(ya)為5V、擊(ji)穿(chuan)電(dian)(dian)(dian)(dian)(dian)壓(ya)6V、鉗位(wei)(wei)電(dian)(dian)(dian)(dian)(dian)壓(ya)18.3V、最大(da)浪(lang)涌(yong)峰(feng)值電(dian)(dian)(dian)(dian)(dian)流可達(da)17A、SOD-323封裝、低結電(dian)(dian)(dian)(dian)(dian)容1pF，確保(bao)傳輸信號完整性，符合IEC 61000-4-2 (ESD) ±30kV（空氣）和 ±30kV（接觸）標準。

2）USB 2.0單接口靜電浪涌(yong)保護方案(an)用(yong)集(ji)成式ESD二極管(guan)

從方案(an)圖中可(ke)知，東沃(wo)電(dian)(dian)(dian)(dian)子技術(shu)推(tui)薦選用(yong)集成式ESD二極管DW05R-E作為靜(jing)電(dian)(dian)(dian)(dian)浪涌防護(hu)。DW05R-E是一款(kuan)可(ke)以同(tong)時(shi)保(bao)護(hu)VBUS和(he)D+/D-引(yin)腳的靜(jing)電(dian)(dian)(dian)(dian)浪涌保(bao)護(hu)器件，工作電(dian)(dian)(dian)(dian)壓為5V、擊(ji)穿電(dian)(dian)(dian)(dian)壓6V、鉗位電(dian)(dian)(dian)(dian)壓16V、最大浪涌峰值電(dian)(dian)(dian)(dian)流可(ke)達6.5A、SOT-143封(feng)裝，符合IEC 61000-4-2 (ESD) ±15kV（空氣）和(he) ±8kV（接觸）標準，具(ju)有0.4pF超低結電(dian)(dian)(dian)(dian)容(rong)，確保(bao)傳(chuan)輸信號完整性，非常適合USB2.0高(gao)速數據傳(chuan)輸。

二、USB2.0雙接口靜電(dian)浪涌(yong)保護方案

在很多應用(yong)場(chang)景中(zhong)，需要配備兩(liang)個(ge)及多個(ge)USB2.0接(jie)口(kou)(kou)，由于(yu)空(kong)(kong)間(jian)受限(xian)，不可能使用(yong)過多的保(bao)護器件。從方案圖中(zhong)可知(zhi)，東(dong)(dong)沃(wo)技術推薦選用(yong)1顆(ke)集成式(shi)ESD二極(ji)管DW05-4RVLC-E和2顆(ke)自恢復(fu)保(bao)險絲DW-NSM050來保(bao)護兩(liang)路(lu)USB2.0接(jie)口(kou)(kou)，提高(gao)設(she)計能力(li)。東(dong)(dong)沃(wo)DW05-4RVLC-E帶4路(lu)I/O數據線保(bao)護，可以同時保(bao)護2路(lu)USB2.0數據口(kou)(kou)，工作電壓為5V、擊穿(chuan)電壓6V、鉗位電壓12V、最(zui)大浪涌峰(feng)值電流(liu)可達(da)4A、其結電容低至0.5pF，保(bao)證高(gao)速信號(hao)的完整傳(chuan)輸；符合IEC 61000-4-2 (ESD) ±20kV（空(kong)(kong)氣）、±12kV（接(jie)觸）標準；采用(yong)SOT-23-6L封裝，節省安裝空(kong)(kong)間(jian)。東(dong)(dong)沃(wo)DW-NSM050在電路(lu)中(zhong)起到(dao)過流(liu)保(bao)護作用(yong)，可承受的最(zui)大工作電流(liu)500mA，耐壓6V，靜(jing)態(tai)電阻最(zui)小0.7Ω。

以上是USB 2.0 接口靜電浪涌保護常用方案，如有特殊需求，歡迎前來探討。浪涌靜電保護方案，找東沃電子，電路防護不迷路！東沃USB 2.0 接口靜電浪涌保護方案中選用到的ESD二極管DW05DP-S、DW05DLC-B-S、DW05R-E、DW05-4RVLC-E和自恢復保險絲DW-NSM050，東沃電子已全面量產、品質穩定、高可靠性、交期迅速、廠家價格、免費樣品、免費EMC測試、免費方案整改設計、免費選型，歡迎廣大新老客戶前來咨詢：137 5773 6996（微信同號）余工