{"id":7159,"date":"2026-06-23T05:52:24","date_gmt":"2026-06-23T05:52:24","guid":{"rendered":"https:\/\/materialparts.com\/l4940d2t5-tr\/"},"modified":"2026-06-23T05:52:24","modified_gmt":"2026-06-23T05:52:24","slug":"l4940d2t5-tr","status":"publish","type":"post","link":"https:\/\/materialparts.com\/ar\/l4940d2t5-tr\/","title":{"rendered":"L4940D2T5-TR"},"content":{"rendered":"

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

The L4940D2T5-TR from STMicroelectronics is a 1.5A low-dropout positive voltage regulator with 5.0V fixed output in a DPAK package. With 0.5V typical dropout at 1.5A, it provides efficient regulation for battery-powered and automotive systems.<\/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
\u062c\u0647\u062f \u0627\u0644\u062e\u0631\u062c<\/td>\n5.0 V (fixed)<\/td>\n<\/tr>\n
\u062a\u064a\u0627\u0631 \u0627\u0644\u0625\u062e\u0631\u0627\u062c<\/td>\n1.5 A<\/td>\n<\/tr>\n
\u062c\u0647\u062f \u0627\u0644\u062a\u0633\u0631\u0628<\/td>\n0.5 V (typical at 1.5A)<\/td>\n<\/tr>\n
\u062c\u0647\u062f \u0627\u0644\u0625\u062f\u062e\u0627\u0644<\/td>\n5.5 V to 25 V<\/td>\n<\/tr>\n
\u062a\u064a\u0627\u0631 \u0627\u0644\u062a\u0647\u062f\u0626\u0629<\/td>\n30 mA (typical at full load)<\/td>\n<\/tr>\n
\u062f\u0631\u062c\u0629 \u062d\u0631\u0627\u0631\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644<\/td>\n-40C to +150C<\/td>\n<\/tr>\n<\/table>\n

\u0627\u0644\u0645\u064a\u0632\u0627\u062a<\/h2>\n
    \n
  • 1.5A output current with 0.5V typical dropout voltage<\/li>\n
  • 5.0V fixed output with 2% initial accuracy<\/li>\n
  • Internal current limiting and thermal shutdown<\/li>\n
  • Reverse battery protection up to -15V<\/td>\n<\/tr>\n

DPAK package for compact thermal design<\/li>\n<\/ul>\n

\u0627\u0644\u062a\u0637\u0628\u064a\u0642\u0627\u062a<\/h2>\n
    \n
  • Automotive ECU 5V regulation from 12V battery<\/li>\n
  • Post-regulation after switching converters<\/li>\n
  • Battery-powered instrumentation 5V supplies<\/li>\n
  • Industrial control logic power<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

    Product Overview The L4940D2T5-TR from STMicroelectronics is a 1.5A low-dropout positive voltage regulator with 5.0V fixed output in a DPAK package. With 0.5V typical dropout at 1.5A, it provides efficient regulation for battery-powered and automotive systems. Key Specifications Output Voltage 5.0 V (fixed) Output Current 1.5 A Dropout Voltage 0.5 V (typical at 1.5A) Input […]<\/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":[13,32],"tags":[],"chip_brand":[142],"class_list":["post-7159","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-low-dropout-regulators-ldo","chip_brand-st"],"acf":{"brief_explanation":"1.5A LDO, 5.0V fixed, 0.5V dropout, DPAK, automotive, thermal shutdown","date_code":"","package_case":"DPAK (6.50 x 5.50 x 2.30 mm)","in_stock":8449,"datasheet":"https:\/\/www.st.com\/resource\/en\/datasheet\/l4940.pdf","price":"$0.85 @ 1ku","product_introduction":"The L4940D2T5-TR from STMicroelectronics is a 1.5A low-dropout positive voltage regulator with a fixed 5.0V output in a DPAK surface-mount package. The device features a PNP pass transistor achieving 0.5V typical dropout voltage at 1.5A output current, significantly lower than standard NPN regulators. The input voltage range extends from 5.5V to 25V, making it suitable for automotive 12V battery systems. The device includes internal current limiting and thermal shutdown protection. Reverse battery protection withstands -15V input without damage. The 2% initial output voltage accuracy ensures reliable logic supply regulation. The DPAK package provides good thermal performance with a low thermal resistance to the PCB copper area. The -40C to +150C operating temperature range supports automotive under-hood applications.","working_principle":"The L4940D2T5-TR uses a PNP pass transistor in a low-dropout configuration. (1) Pass Element: A PNP power transistor allows the input-to-output voltage differential to be as low as 0.5V while maintaining regulation. Unlike NPN regulators that require at least 2V headroom, the PNP topology provides efficient regulation even when VIN is close to VOUT. (2) Error Amplifier: A precision voltage divider and error amplifier compare a fraction of the output voltage to an internal bandgap reference. The error amplifier drives the PNP pass transistor base to maintain the output at 5.0V. (3) Protection: Internal current limiting protects against output short circuits by reducing the pass transistor base drive when the output current exceeds approximately 2.5A. Thermal shutdown disables the output when junction temperature exceeds approximately 150C. (4) Reverse Battery: The PNP transistor structure blocks reverse current flow when the input voltage is negative, protecting the load from reverse battery conditions up to -15V.","pin_description":"
    Pin<\/th>Name<\/th>Type<\/th>Function<\/th><\/tr>
    1<\/td>GND<\/td>Ground<\/td>Ground \/ tab<\/td><\/tr>
    2<\/td>VOUT<\/td>Output<\/td>Regulated 5.0V output<\/td><\/tr>
    3<\/td>VIN<\/td>Input<\/td>Input supply (5.5-25V)<\/td><\/tr><\/table>","application_scenarios":"
    • Automotive ECU 5V regulation from 12V battery with reverse protection<\/li>
    • Post-regulation after switching converters with 0.5V low dropout<\/li>
    • Battery-powered instrumentation 5V supplies in DPAK package<\/li>
    • Industrial control logic power with thermal shutdown protection<\/li><\/ul>","alternative_models":"
      Manufacturer<\/th>Part Number<\/th>Package<\/th>Notes<\/th><\/tr>
      ST<\/td>L4940V5<\/td>TO-220<\/td>Through-hole version<\/td><\/tr>
      TI<\/td>UA78M05CDCYR<\/td>SOT-223<\/td>500mA, higher dropout<\/td><\/tr>
      onsemi<\/td>MC33269DT-5.0G<\/td>DPAK<\/td>800mA LDO, 5V<\/td><\/tr>
      Infineon<\/td>TLE4274DNT<\/td>SOT-223<\/td>200mA, automotive 5V<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/7159","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=7159"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/7159\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/media?parent=7159"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/categories?post=7159"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/tags?post=7159"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/chip_brand?post=7159"}],"curies":[{"name":"\u062f\u0628\u0644\u064a\u0648 \u0628\u064a","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}