{"id":10281,"date":"2026-07-09T10:06:38","date_gmt":"2026-07-09T10:06:38","guid":{"rendered":"https:\/\/materialparts.com\/bm04b-xass-tflfsn\/"},"modified":"2026-07-09T10:06:38","modified_gmt":"2026-07-09T10:06:38","slug":"bm04b-xass-tflfsn","status":"publish","type":"post","link":"https:\/\/materialparts.com\/zh\/bm04b-xass-tflfsn\/","title":{"rendered":"BM04B-XASS-TF(LF)(SN)"},"content":{"rendered":"

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

The BM04B-XASS-TF(LF)(SN) from JST is a 4-position 2.5mm pitch XA series Shrouded Header with Secure Lock, designed for Top-Entry (Straight) surface-mount applications. Rated at 3A and 250V AC\/DC, this connector provides reliable wire-to-board connectivity in a compact form factor.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
\u5236\u9020\u5546<\/td>\nJST<\/td>\n<\/tr>\n
Series<\/td>\nXA<\/td>\n<\/tr>\n
Pitch<\/td>\n2.5 mm<\/td>\n<\/tr>\n
Number of Positions<\/td>\n4<\/td>\n<\/tr>\n
\u5b89\u88c5\u7c7b\u578b<\/td>\nSMT<\/td>\n<\/tr>\n
Orientation<\/td>\nTop-Entry (Straight)<\/td>\n<\/tr>\n
Current Rating<\/td>\n3A<\/td>\n<\/tr>\n
Voltage Rating<\/td>\n250V AC\/DC<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n-25\u00b0C to +85\u00b0C<\/td>\n<\/tr>\n
Contact Material<\/td>\nCopper Alloy \/ Phosphor Bronze<\/td>\n<\/tr>\n
Contact Plating<\/td>\nTin (Sn)<\/td>\n<\/tr>\n
Insulation Material<\/td>\nNylon (PA) \/ PBT, UL94V-0<\/td>\n<\/tr>\n
RoHS Compliant<\/td>\nYes<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • 2.5mm pitch disconnectable crimp-style connector with secure lock<\/li>\n
  • Top-entry (straight) SMT configuration<\/li>\n
  • 4-position single-row layout<\/li>\n
  • Solder crack preventive PA66 housing<\/li>\n
  • Insertion guide mechanism for easy mating<\/li>\n
  • Polarizing boss for PCB alignment<\/li>\n
  • Flip-type tape and reel packaging (TF)<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • Relay connections<\/li>\n
    • Industrial control wiring<\/li>\n
    • Power supply distribution<\/li>\n
    • Home appliance connections<\/li>\n
    • Office automation equipment<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The BM04B-XASS-TF(LF)(SN) from JST is a 4-position 2.5mm pitch XA series Shrouded Header with Secure Lock, designed for Top-Entry (Straight) surface-mount applications. Rated at 3A and 250V AC\/DC, this connector provides reliable wire-to-board connectivity in a compact form factor. Key Specifications Manufacturer JST Series XA Pitch 2.5 mm Number of Positions 4 Mounting […]<\/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":[66],"tags":[1527],"chip_brand":[243],"class_list":["post-10281","post","type-post","status-publish","format-standard","hentry","category-connectors-interconnect-devices","tag-bm04b-xass-tflfsn","chip_brand-jst"],"acf":{"brief_explanation":"JST XA Series 2.5mm pitch, 4-circuit SMT top-entry shrouded header with secure lock, 3A, 250V, tin-plated, lead-free","date_code":"","package_case":"SMT Header (2.5mm pitch, 4 pos, top-entry, secure lock)","in_stock":8912,"datasheet":"https:\/\/www.jst-mfg.com\/product\/pdf\/eng\/eXA.pdf","price":"","product_introduction":"The BM04B-XASS-TF(LF)(SN) is a 4-position 2.5mm pitch surface-mount top-entry shrouded header from JST's XA connector series. The XA series is designed for relay connections and power applications, featuring a secure locking device that prevents accidental disconnection due to vibration or cable routing. The glass-filled PA66 nylon housing is specifically formulated to prevent solder cracking during thermal cycling, which is a common issue with through-hole and SMT connectors in power applications. The 3A current rating and 250V voltage rating make this connector suitable for both power delivery and signal routing in industrial and consumer equipment.","working_principle":"The BM04B-XASS-TF(LF)(SN) operates as part of the XA connector system. The header features rounded pin contacts made of copper alloy with tin plating (reflow-treated), which provide low insertion force during mating. The secure lock ramp engages with the XAP-04V-1 housing to prevent accidental disconnection. The TF flip-type tape packaging presents the connector with contacts facing upward in the embossed carrier tape, suitable for specific pick-and-place configurations. The glass-filled PA66 housing material has a CTE (coefficient of thermal expansion) that closely matches typical FR-4 PCB material, reducing thermal stress on solder joints during reflow and operational thermal cycling.","pin_description":"
      Pin<\/th>Name<\/th>Type<\/th>Function<\/th><\/tr>
      1<\/td>Circuit 1<\/td>Signal\/Power<\/td>First contact position<\/td><\/tr>
      2<\/td>Circuit 2<\/td>Signal\/Power<\/td>Second contact position<\/td><\/tr>
      3<\/td>Circuit 3<\/td>Signal\/Power<\/td>Third contact position<\/td><\/tr>
      4<\/td>Circuit 4<\/td>Signal\/Power<\/td>Fourth contact position<\/td><\/tr><\/table>","application_scenarios":"
      • Relay Connections:<\/strong> Coil and contact connections for PCB-mounted relays with 2.5mm pitch matching standard relay pin spacing.<\/li>
      • Industrial Control:<\/strong> PLC I\/O module connections with secure lock preventing disconnection in vibrating environments.<\/li>
      • Power Distribution:<\/strong> Board-level power supply connections with 3A per circuit and 250V rating supporting 24V and 48V industrial rails.<\/li>
      • Home Appliances:<\/strong> Control board to power supply wiring in washers, dryers, and HVAC equipment.<\/li><\/ul>","alternative_models":"
        Manufacturer<\/th>Part Number<\/th>Pitch<\/th>Circuits<\/th>Notes<\/th><\/tr>
        JST<\/td>S04B-XASS-1(LF)(SN)<\/td>2.5mm<\/td>4<\/td>Through-hole side-entry variant<\/td><\/tr>
        JST<\/td>BM06B-XASS-TF(LF)(SN)<\/td>2.5mm<\/td>6<\/td>6-circuit version<\/td><\/tr>
        JST<\/td>B04B-PASK-1(LF)(SN)<\/td>2.0mm<\/td>4<\/td>PA series alternative<\/td><\/tr>
        Molex<\/td>39-28-1044<\/td>2.5mm<\/td>4<\/td>KK250 alternative<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/10281","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/comments?post=10281"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/10281\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/media?parent=10281"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/categories?post=10281"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/tags?post=10281"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=10281"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}