{"id":3344,"date":"2026-06-03T04:17:41","date_gmt":"2026-06-03T04:17:41","guid":{"rendered":"https:\/\/materialparts.com\/bd681\/"},"modified":"2026-06-03T04:17:41","modified_gmt":"2026-06-03T04:17:41","slug":"bd681","status":"publish","type":"post","link":"https:\/\/materialparts.com\/ar\/bd681\/","title":{"rendered":"BD681"},"content":{"rendered":"

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

The BD681 from STMicroelectronics is a PNP Darlington power transistor in a SOT-32 (TO-126) package. Rated at -80V VCEO and -4A continuous collector current with a minimum DC current gain (hFE) of 750 at IC=2A. Designed for medium-power switching and amplification in industrial and consumer applications. Complementary pair with BD682 (NPN).<\/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\n
\u0627\u0644\u0642\u0637\u0628\u064a\u0629<\/td>\nPNP Darlington<\/td>\n<\/tr>\n
VCEO<\/td>\n-80V<\/td>\n<\/tr>\n
IC (Continuous)<\/td>\n-4A<\/td>\n<\/tr>\n
IC (Peak)<\/td>\n-6A<\/td>\n<\/tr>\n
hFE (min) @ IC=2A<\/td>\n750<\/td>\n<\/tr>\n
VCE(sat) max<\/td>\n-1.5V @ IC=2A, IB=8mA<\/td>\n<\/tr>\n
VBE(on) max<\/td>\n-1.8V @ IC=3A<\/td>\n<\/tr>\n
\u062a\u0628\u062f\u064a\u062f \u0627\u0644\u0637\u0627\u0642\u0629<\/td>\n40W (TC=25 C)<\/td>\n<\/tr>\n
\u062f\u0631\u062c\u0629 \u062d\u0631\u0627\u0631\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644<\/td>\n-65 to 150 C<\/td>\n<\/tr>\n
\u0627\u0644\u062d\u0632\u0645\u0629<\/td>\nSOT-32 (TO-126)<\/td>\n<\/tr>\n<\/table>\n

\u0627\u0644\u0645\u064a\u0632\u0627\u062a<\/h2>\n
    \n
  • PNP Darlington configuration<\/li>\n
  • High current gain: hFE > 750 at 2A<\/li>\n
  • 80V collector-emitter voltage<\/li>\n
  • 4A continuous, 6A peak current<\/li>\n
  • 40W power dissipation (with heatsink)<\/li>\n
  • Internal base-emitter resistors for stability<\/li>\n
  • Complementary pair with BD682 (NPN)<\/li>\n<\/ul>\n

    \u0627\u0644\u062a\u0637\u0628\u064a\u0642\u0627\u062a<\/h2>\n
      \n
    • Medium-power switching (relays, solenoids, motors)<\/li>\n
    • Audio output amplifiers<\/li>\n
    • Lamp and LED drivers<\/li>\n
    • Power supply regulators<\/li>\n
    • Heater and actuator control<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The BD681 from STMicroelectronics is a PNP Darlington power transistor in a SOT-32 (TO-126) package. Rated at -80V VCEO and -4A continuous collector current with a minimum DC current gain (hFE) of 750 at IC=2A. Designed for medium-power switching and amplification in industrial and consumer applications. Complementary pair with BD682 (NPN). Key Specifications […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[13,56],"tags":[],"chip_brand":[142],"class_list":["post-3344","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-mosfets","chip_brand-st"],"acf":{"brief_explanation":"PNP Darlington, -80V, -4A, hFE>750, SOT-32, complement to BD682","date_code":"","package_case":"SOT-32 \/ TO-126 (5.4 x 6.2 x 2.3 mm, tab=collector)","in_stock":8340,"datasheet":"https:\/\/www.st.com\/resource\/en\/datasheet\/bd681.pdf","price":"$0.52 @ 1ku","product_introduction":"The BD681 from ST is a PNP Darlington power transistor rated at -80V, -4A in SOT-32 (TO-126) package. The Darlington configuration provides hFE > 750 at IC=2A, enabling direct drive from low-current logic. Internal base-emitter resistors ensure thermal stability. Complementary pair with BD682 (NPN). Suitable for medium-power switching, motor control, and audio amplification.","working_principle":"The Darlington configuration cascades two PNP transistors: the first (driver) collector feeds the second (output) base. The combined current gain is the product of both transistor hFE values, yielding >750. Internal base-emitter shunt resistors prevent leakage current from turning on the output transistor and improve switching speed by providing a discharge path for stored base charge. VCE(sat) is higher (~1.5V) than a single transistor due to the two VBE drops.","pin_description":"
      Pin<\/th>Name<\/th>Type<\/th>Function<\/th><\/tr>
      1<\/td>Base<\/td>Input<\/td>Darlington base input<\/td><\/tr>
      2<\/td>Collector<\/td>Output<\/td>Collector (heatsink tab)<\/td><\/tr>
      3<\/td>Emitter<\/td>Output<\/td>Emitter<\/td><\/tr><\/table>","application_scenarios":"
      • Motor H-bridge high-side PNP switch driven directly from MCU GPIO<\/li>
      • Relay and solenoid driver with high gain<\/li>
      • Audio amplifier output stage (complementary with BD682)<\/li>
      • LED\/lamp driver for high-current loads<\/li>
      • Linear voltage regulator pass element<\/li><\/ul>","alternative_models":"
        Manufacturer<\/th>Part Number<\/th>Package<\/th>Notes<\/th><\/tr>
        ST<\/td>BD682<\/td>SOT-32<\/td>NPN complementary Darlington<\/td><\/tr>
        onsemi<\/td>TIP127<\/td>TO-220<\/td>PNP Darlington, -5A, TO-220<\/td><\/tr>
        ST<\/td>BD681G<\/td>SOT-32<\/td>Lead-free variant<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/3344","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=3344"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/3344\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/media?parent=3344"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/categories?post=3344"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/tags?post=3344"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/chip_brand?post=3344"}],"curies":[{"name":"\u062f\u0628\u0644\u064a\u0648 \u0628\u064a","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}