{"id":6442,"date":"2026-06-16T03:43:39","date_gmt":"2026-06-16T03:43:39","guid":{"rendered":"https:\/\/materialparts.com\/sm712-tct\/"},"modified":"2026-06-16T03:43:39","modified_gmt":"2026-06-16T03:43:39","slug":"sm712-tct","status":"publish","type":"post","link":"https:\/\/materialparts.com\/ar\/sm712-tct\/","title":{"rendered":"SM712.TCT"},"content":{"rendered":"

\u0646\u0638\u0631\u0629 \u0639\u0627\u0645\u0629 \u0639\u0644\u0649 \u0627\u0644\u0645\u0646\u062a\u062c<\/h2>\n

The SM712.TCT from Semtech is a bidirectional TVS diode array specifically designed for RS-485 and RS-422 interface protection. With a working voltage of \u00b112V to match RS-485 common-mode ranges, it provides IEC 61000-4-2 ESD protection up to \u00b130kV contact discharge. The low capacitance of 75pF per channel and low clamping voltage of 16V at 5A ensure signal integrity while protecting transceivers from transient threats.<\/p>\n

\u0627\u0644\u0645\u0648\u0627\u0635\u0641\u0627\u062a \u0627\u0644\u0631\u0626\u064a\u0633\u064a\u0629<\/h2>\n\n\n\n\n\n\n\n\n\n\n
\u0627\u0644\u0642\u0646\u0648\u0627\u062a<\/td>\n2 (bidirectional)<\/td>\n<\/tr>\n
Working Voltage (VRWM)<\/td>\n\u00b112V<\/td>\n<\/tr>\n
Breakdown Voltage (VBR)<\/td>\n14V min<\/td>\n<\/tr>\n
Clamping Voltage (VC)<\/td>\n16V max @ IPP = 5A<\/td>\n<\/tr>\n
Capacitance<\/td>\n75pF per channel<\/td>\n<\/tr>\n
ESD Protection<\/td>\nIEC 61000-4-2: \u00b130kV contact<\/td>\n<\/tr>\n
Leakage Current<\/td>\n1\u00b5A max @ VRWM<\/td>\n<\/tr>\n
\u0627\u0644\u062d\u0632\u0645\u0629<\/td>\nSOT-23 (3.0 x 1.3mm)<\/td>\n<\/tr>\n
\u062f\u0631\u062c\u0629 \u062d\u0631\u0627\u0631\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644<\/td>\n-55 \u062f\u0631\u062c\u0629 \u0645\u0626\u0648\u064a\u0629 \u0625\u0644\u0649 +125 \u062f\u0631\u062c\u0629 \u0645\u0626\u0648\u064a\u0629<\/td>\n<\/tr>\n<\/table>\n

\u0627\u0644\u0645\u064a\u0632\u0627\u062a<\/h2>\n
    \n
  • Bidirectional protection for RS-485\/RS-422 data lines<\/li>\n

\u00b112V working voltage matches RS-485 common-mode range<\/li>\n
  • IEC 61000-4-2 Level 4 ESD protection (\u00b130kV)<\/li>\n
  • Low clamping voltage: 16V at 5A protects transceiver inputs<\/li>\n
  • 75pF per-channel capacitance suitable for RS-485 data rates<\/li>\n
  • Low leakage current: 1\u00b5A max<\/li>\n
  • Compact SOT-23 package for board-edge placement<\/li>\n
  • Also protects against EFT and surge per IEC 61000-4-4\/5<\/li>\n<\/ul>\n

    \u0627\u0644\u062a\u0637\u0628\u064a\u0642\u0627\u062a<\/h2>\n
      \n
    • RS-485 and RS-422 transceiver protection<\/li>\n
    • Industrial communication bus protection<\/li>\n
    • Profibus, Modbus, and DMX512 interfaces<\/li>\n
    • Building automation and HVAC controllers<\/li>\n
    • Motor drive communication ports<\/li>\n
    • Automotive LIN bus protection<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The SM712.TCT from Semtech is a bidirectional TVS diode array specifically designed for RS-485 and RS-422 interface protection. With a working voltage of \u00b112V to match RS-485 common-mode ranges, it provides IEC 61000-4-2 ESD protection up to \u00b130kV contact discharge. The low capacitance of 75pF per channel and low clamping voltage of 16V […]<\/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":[13,20],"tags":[],"chip_brand":[189],"class_list":["post-6442","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-interface-ics","chip_brand-semtech"],"acf":{"brief_explanation":"Bidirectional TVS for RS-485, \u00b112V VRWM, \u00b130kV ESD, 75pF, 16V clamp, SOT-23","date_code":"","package_case":"SOT-23 (3.0 x 1.3 x 1.0mm)","in_stock":6780,"datasheet":"https:\/\/www.semtech.com\/uploads\/documents\/sm712.pdf","price":"$0.18 @ 1ku","product_introduction":"The SM712.TCT is a bidirectional transient voltage suppression (TVS) diode array from Semtech, specifically designed for RS-485 and RS-422 interface protection. The \u00b112V working voltage precisely matches the RS-485 common-mode voltage range of -7V to +12V, allowing the device to protect both the A and B bus lines without interfering with normal signal levels. It provides IEC 61000-4-2 Level 4 ESD protection up to \u00b130kV contact discharge, as well as protection against electrical fast transients (EFT) and surge events. The low clamping voltage of 16V at 5A ensures that the protected transceiver's absolute maximum ratings are not exceeded. The compact SOT-23 package allows placement directly at the connector for maximum effectiveness.","working_principle":"The SM712 contains two bidirectional TVS diode structures, each connected between a protected line (A or B) and ground. Under normal operation, the RS-485 signal on each line swings between the common-mode limits (-7V to +12V). The TVS diodes remain in their high-impedance state with only 1\u00b5A leakage, having no effect on the signal. When a transient event (ESD, EFT, or surge) pushes the line voltage beyond the \u00b112V working voltage, the TVS diode avalanches, shunting the transient current to ground. The bidirectional structure provides equal protection for both positive and negative transients. The low clamping voltage (16V at 5A) limits the voltage seen by the transceiver to a safe level. The 75pF capacitance is low enough to not degrade RS-485 signal quality at standard data rates up to 10Mbps.","pin_description":"
      Pin<\/th>Name<\/th>Description<\/th><\/tr>
      1<\/td>Line 1 (A)<\/td>Protected RS-485 line A (non-inverting)<\/td><\/tr>
      2<\/td>GND<\/td>Ground connection<\/td><\/tr>
      3<\/td>Line 2 (B)<\/td>Protected RS-485 line B (inverting)<\/td><\/tr><\/table>","application_scenarios":"
      • Industrial RS-485 Bus Protection:<\/b> Place the SM712 at the connector where the RS-485 bus enters the PCB. Connect pin 1 to line A and pin 3 to line B, with pin 2 connected to the bus ground or shield. The \u00b112V working voltage accommodates the full RS-485 common-mode range, while the \u00b130kV ESD rating handles cable discharge events common in long industrial cable runs.<\/li>
      • Modbus\/Profibus Port Protection:<\/b> Protect the RS-485 transceiver on Modbus RTU or Profibus DP slave nodes. The low 75pF capacitance does not degrade signal quality at Profibus data rates (up to 12Mbps). Position the SM712 within 10mm of the connector for maximum ESD shunting effectiveness.<\/li>
      • Building Automation Controller:<\/b> Protect HVAC and BACnet controller communication ports. Cable runs in buildings are susceptible to nearby lightning strikes and switching transients. The SM712's surge capability (5A) handles these events, while the SOT-23 package fits on the crowded connector area of multi-port controllers.<\/li><\/ul>","alternative_models":"
        Model<\/th>VRWM<\/th>ESD Rating<\/th>Capacitance<\/th>Key Difference<\/th><\/tr>
        SM712-02HTG<\/td>\u00b112V<\/td>\u00b130kV<\/td>75pF<\/td>Same in SOT-23-6L package<\/td><\/tr>
        TISP4240M3BJR-S<\/td>\u00b112V<\/td>\u00b18kV<\/td>60pF<\/td>Bourns alternative, lower cap<\/td><\/tr>
        PRTR5V0U2X<\/td>5V<\/td>\u00b18kV<\/td>0.9pF<\/td>Nexperia, USB, not RS-485<\/td><\/tr>
        NUP4201MR6<\/td>5V<\/td>\u00b115kV<\/td>4pF<\/td>onsemi, CAN bus protection<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/6442","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/comments?post=6442"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/6442\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/media?parent=6442"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/categories?post=6442"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/tags?post=6442"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/chip_brand?post=6442"}],"curies":[{"name":"\u062f\u0628\u0644\u064a\u0648 \u0628\u064a","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}