{"id":9606,"date":"2026-07-04T10:33:19","date_gmt":"2026-07-04T10:33:19","guid":{"rendered":"https:\/\/ic-vendor.com\/smbj120a\/"},"modified":"2026-07-04T10:33:19","modified_gmt":"2026-07-04T10:33:19","slug":"smbj120a","status":"publish","type":"post","link":"https:\/\/ic-vendor.com\/zh\/smbj120a\/","title":{"rendered":"SMBJ120A"},"content":{"rendered":"

\u4ea7\u54c1\u6982\u89c8<\/h2>\n

The SMBJ120A is a 600 W surface-mount transient voltage suppressor (TVS) diode in a DO-214AA (SMB) package, designed to protect sensitive electronics from voltage transients induced by lightning and other transient events. With a reverse standoff voltage of 120 V and a maximum clamping voltage of 193 V at 3.1 A peak pulse current, it is suitable for protecting 120 V nominal bus lines and telecom interfaces.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n
Reverse Standoff Voltage (VRWM)<\/td>\n120 V<\/td>\n<\/tr>\n
Breakdown Voltage (VBR)<\/td>\n133 V min \/ 147 V max<\/td>\n<\/tr>\n
Maximum Clamping Voltage (VC)<\/td>\n193 V @ IPP = 3.1 A<\/td>\n<\/tr>\n
Peak Pulse Power (10\/1000 \u00b5s)<\/td>\n600 W<\/td>\n<\/tr>\n
Peak Pulse Current (IPP)<\/td>\n3.1 A<\/td>\n<\/tr>\n
Reverse Leakage (IR)<\/td>\n1 \u00b5A max @ VRWM<\/td>\n<\/tr>\n
\u6781\u6027<\/td>\nUnidirectional<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n-65\u00b0C to 150\u00b0C<\/td>\n<\/tr>\n
\u5305\u88c5<\/td>\nDO-214AA (SMB)<\/td>\n<\/tr>\n
ESD Rating<\/td>\nIEC 61000-4-2: 15 kV Air \/ 8 kV Contact<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • 600 W peak pulse power dissipation at 10\/1000 \u00b5s waveform<\/li>\n
  • Low incremental surge resistance for excellent clamping capability<\/li>\n
  • Fast response time: typically less than 1.0 ps from 0 V to BV min<\/li>\n
  • Glass passivated chip junction for reliable operation<\/li>\n
  • Typical failure mode is short circuit for fail-safe protection<\/li>\n
  • IEC 61000-4-2 ESD protection: 15 kV air, 8 kV contact<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • Telecom line card transient protection<\/li>\n
    • 120 V DC bus protection in industrial power supplies<\/li>\n
    • Automotive 24 V\/48 V system overvoltage protection<\/li>\n
    • Consumer electronics input port ESD\/surge protection<\/li>\n
    • LED lighting driver transient suppression<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The SMBJ120A is a 600 W surface-mount transient voltage suppressor (TVS) diode in a DO-214AA (SMB) package, designed to protect sensitive electronics from voltage transients induced by lightning and other transient events. With a reverse standoff voltage of 120 V and a maximum clamping voltage of 193 V at 3.1 A peak pulse […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[13,44],"tags":[855],"chip_brand":[200],"class_list":["post-9606","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-pressure-sensors","tag-smbj120a","chip_brand-littelfuse"],"acf":{"brief_explanation":"600W unidirectional TVS diode, 120V standoff, 193V clamp, DO-214AA (SMB)","date_code":"","package_case":"DO-214AA (SMB)","in_stock":11312,"datasheet":"https:\/\/www.littelfuse.com\/media\/?fHandle=NTc0Mg==&fType=2&fID=7243.3","price":"$0.42 @ 10+","product_introduction":"The SMBJ120A is a 600 W transient voltage suppressor diode from the Littelfuse SMBJ series, designed for surface-mount applications to protect sensitive electronic equipment from voltage transients induced by lightning and other transient events. The unidirectional device has a reverse standoff voltage of 120 V and clamps transients to a maximum of 193 V at 3.1 A peak pulse current. The glass passivated chip junction ensures reliable operation, while the typical failure mode is a short circuit, providing fail-safe protection. The DO-214AA (SMB) package offers a low-profile surface-mount footprint optimized for board space.","working_principle":"The SMBJ120A operates as a voltage-clamping device: (1) Normal Operation \u2014 below the reverse standoff voltage (120 V), the TVS diode presents a very high impedance (leakage < 1 \u00b5A), effectively invisible to the protected circuit; (2) Transient Event \u2014 when a voltage spike exceeds the breakdown voltage (133\u2013147 V), the device avalanches and conducts heavily, clamping the voltage across its terminals to the maximum clamping voltage (193 V at 3.1 A), thereby diverting surge energy away from the protected load; (3) Recovery \u2014 after the transient subsides, the device returns to its high-impedance state. The unidirectional configuration provides clamping for positive transients and forward diode conduction for negative transients. The 600 W peak pulse power rating at 10\/1000 \u00b5s waveform ensures sufficient energy absorption for typical surge events.","pin_description":"
      Pin<\/th>Function<\/th><\/tr>
      Cathode (band side)<\/td>Positive terminal \u2014 connect toward the protected line<\/td><\/tr>
      Anode<\/td>Negative terminal \u2014 connect toward ground<\/td><\/tr><\/table>","application_scenarios":"
      • Telecom line card protecting SLIC circuits from lightning-induced surges on 120 V tip\/ring lines<\/li>
      • Industrial 120 V DC bus protection against load-dump and switching transients<\/li>
      • Automotive 48 V mild-hybrid bus overvoltage protection with 15 kV ESD rating<\/li>
      • Consumer electronics AC\/DC power adapter output transient suppression<\/li>
      • LED street lighting driver input protection against surge events per IEC 61000-4-5<\/li><\/ul>","alternative_models":"
        Model<\/th>Manufacturer<\/th>Key Difference<\/th><\/tr>
        SMBJ120CA<\/td>Littelfuse<\/td>Bidirectional version for AC signal protection<\/td><\/tr>
        SMAJ120A<\/td>Littelfuse<\/td>400 W version in smaller DO-214AC (SMA) package<\/td><\/tr>
        SMCJ120A<\/td>Littelfuse<\/td>1500 W version in larger DO-214AB (SMC) package<\/td><\/tr>
        P6KE120A<\/td>Various<\/td>600 W through-hole alternative in DO-15 package<\/td><\/tr>
        1.5SMC120A<\/td>STMicroelectronics<\/td>1500 W SMC alternative<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/posts\/9606","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/comments?post=9606"}],"version-history":[{"count":0,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/posts\/9606\/revisions"}],"wp:attachment":[{"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/media?parent=9606"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/categories?post=9606"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/tags?post=9606"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/ic-vendor.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=9606"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}