{"id":11175,"date":"2026-07-24T14:41:18","date_gmt":"2026-07-24T14:41:18","guid":{"rendered":"https:\/\/ic-vendor.com\/0440004-wra\/"},"modified":"2026-07-24T14:41:18","modified_gmt":"2026-07-24T14:41:18","slug":"0440004-wra","status":"publish","type":"post","link":"https:\/\/ic-vendor.com\/ar\/0440004-wra\/","title":{"rendered":"0440004.WRA"},"content":{"rendered":"

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

The Littelfuse 0440004.WRA is a 4A, 250VAC fast-acting (WR series) nano fuse in a 0603 chip package. Designed for overcurrent protection in space-constrained applications, it provides precise protection with DC cold resistance of approximately 150m\u03a9.<\/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
Rated Current<\/td>\n4 A<\/td>\n<\/tr>\n
Rated Voltage<\/td>\n250 VAC \/ 125 VDC<\/td>\n<\/tr>\n
Breaking Capacity<\/td>\n50A @ 250VAC<\/td>\n<\/tr>\n
Cold Resistance<\/td>\n~150 m\u03a9<\/td>\n<\/tr>\n
Melting I\u00b2t<\/td>\n~2.0 A\u00b2s<\/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
\u0627\u0644\u062d\u0632\u0645\u0629<\/td>\n0603 (1608 Metric)<\/td>\n<\/tr>\n<\/table>\n

\u0627\u0644\u0645\u064a\u0632\u0627\u062a<\/h2>\n
    \n
  • Ultra-small 0603 chip fuse<\/li>\n
  • Fast-acting time-current characteristic<\/li>\n
  • High breaking capacity at 250VAC<\/li>\n
  • Precise 4A current rating<\/li>\n
  • Surface mount, reflow solderable<\/li>\n
  • RoHS compliant<\/li>\n<\/ul>\n

    \u0627\u0644\u062a\u0637\u0628\u064a\u0642\u0627\u062a<\/h2>\n
      \n
    • Consumer electronics overcurrent protection<\/li>\n
    • Battery pack protection<\/li>\n
    • USB port current limiting<\/li>\n
    • Portable device protection<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The Littelfuse 0440004.WRA is a 4A, 250VAC fast-acting (WR series) nano fuse in a 0603 chip package. Designed for overcurrent protection in space-constrained applications, it provides precise protection with DC cold resistance of approximately 150m\u03a9. Key Specifications Rated Current 4 A Rated Voltage 250 VAC \/ 125 VDC Breaking Capacity 50A @ 250VAC […]<\/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":[13,56],"tags":[2447],"chip_brand":[200],"class_list":["post-11175","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-mosfets","tag-0440004-wra","chip_brand-littelfuse"],"acf":{"brief_explanation":"4A 250VAC fast-acting nano fuse, 0603 SMD, -55 to 125C, RoHS","date_code":"","package_case":"0603 (1608 Metric, 1.6x0.8mm)","in_stock":12456,"datasheet":"https:\/\/www.littelfuse.com\/~\/media\/electronics\/datasheets\/fuses\/littelfuse_fuse_044_datasheet.pdf.pdf","price":"","product_introduction":"The 0440004.WRA from Littelfuse is a 4A, 250VAC fast-acting chip fuse from the nanoSMDC 044 series in a 0603 (1608 metric) package. It provides precise overcurrent protection in ultra-compact form, suitable for space-constrained electronics. The fast-acting characteristic opens quickly under overcurrent conditions to protect sensitive downstream circuitry. With 50A breaking capacity at 250VAC and operation from -55\u00b0C to +125\u00b0C, it is suitable for a wide range of consumer and industrial applications.","working_principle":"The 0440004.WRA uses a thin-film fuse element deposited on a ceramic substrate. Under normal operation, current flows through the element with minimal voltage drop. When current exceeds the 4A rating for a sufficient duration (determined by the fast-acting time-current curve), the element heats and melts, creating an open circuit. The I\u00b2t melting integral (~2.0 A\u00b2s) defines the minimum energy required to open the fuse. The fast-acting characteristic provides quick protection for sensitive semiconductor devices.","pin_description":"
      Pin<\/th>Name<\/th>Type<\/th>Description<\/th><\/tr>
      1<\/td>Terminal A<\/td>Passive<\/td>Fuse terminal 1<\/td><\/tr>
      2<\/td>Terminal B<\/td>Passive<\/td>Fuse terminal 2<\/td><\/tr><\/table>","application_scenarios":"
      • Consumer electronics power rail protection<\/li>
      • Battery pack and charging protection<\/li>
      • USB port overcurrent limiting<\/li>
      • Portable and wearable device protection<\/li><\/ul>","alternative_models":"
        Model<\/th>Manufacturer<\/th>Key Difference<\/th><\/tr>
        0440003.WRA<\/td>Littelfuse<\/td>3A lower rating<\/td><\/tr>
        0603L400SLTH<\/td>Littelfuse<\/td>4A, slow-blow alternative<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/posts\/11175","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/comments?post=11175"}],"version-history":[{"count":0,"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/posts\/11175\/revisions"}],"wp:attachment":[{"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/media?parent=11175"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/categories?post=11175"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/tags?post=11175"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/ic-vendor.com\/ar\/wp-json\/wp\/v2\/chip_brand?post=11175"}],"curies":[{"name":"\u062f\u0628\u0644\u064a\u0648 \u0628\u064a","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}