{"id":7532,"date":"2026-06-25T07:58:11","date_gmt":"2026-06-25T07:58:11","guid":{"rendered":"https:\/\/materialparts.com\/is281-4\/"},"modified":"2026-06-25T07:58:11","modified_gmt":"2026-06-25T07:58:11","slug":"is281-4","status":"publish","type":"post","link":"https:\/\/materialparts.com\/zh\/is281-4\/","title":{"rendered":"IS281-4"},"content":{"rendered":"

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

The IS281-4 from Isocom Components is a 4-channel transistor output optocoupler in 16-pin PDIP through-hole package. Provides 5000Vrms galvanic isolation for industrial signal coupling.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n
\u6e20\u9053<\/td>\n4<\/td>\n<\/tr>\n
\u9694\u79bb\u7535\u538b<\/td>\n5000 Vrms<\/td>\n<\/tr>\n
CTR (Current Transfer Ratio)<\/td>\n50% to 300% @ IF=5mA<\/td>\n<\/tr>\n
Input Forward Current<\/td>\n60 mA max<\/td>\n<\/tr>\n
Output Collector Current<\/td>\n50 mA max per channel<\/td>\n<\/tr>\n
Output Collector-Emitter Voltage<\/td>\n80V (BVCEO)<\/td>\n<\/tr>\n
Bandwidth<\/td>\nDC to 300 kHz typical<\/td>\n<\/tr>\n
Input-Output Capacitance<\/td>\n0.6 pF typical<\/td>\n<\/tr>\n
\u5305\u88c5<\/td>\n16-Pin PDIP (through-hole)<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n-55 to +100 C<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • 4 isolated channels in a single 16-pin DIP package<\/li>\n
  • 5000Vrms isolation voltage for safety-critical applications<\/li>\n
  • Through-hole PDIP package for easy prototyping and repair<\/li>\n
  • 80V collector-emitter breakdown voltage for 24V industrial logic<\/li>\n
  • Wide CTR range of 50% to 300% for design flexibility<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • Industrial control signal isolation<\/li>\n
    • Power supply feedback loop isolation<\/li>\n
    • Medical equipment patient isolation<\/li>\n
    • Communication interface ground loop elimination<\/li>\n
    • PLC digital I\/O module isolation<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The IS281-4 from Isocom Components is a 4-channel transistor output optocoupler in 16-pin PDIP through-hole package. Provides 5000Vrms galvanic isolation for industrial signal coupling. Key Specifications Channels 4 Isolation Voltage 5000 Vrms CTR (Current Transfer Ratio) 50% to 300% @ IF=5mA Input Forward Current 60 mA max Output Collector Current 50 mA max […]<\/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":[309],"class_list":["post-7532","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-interface-ics","chip_brand-isocom"],"acf":{"brief_explanation":"4-ch optocoupler, 5000Vrms, 16-Pin PDIP through-hole","date_code":"","package_case":"16-Pin PDIP (19.7 x 6.5 x 4.6 mm)","in_stock":1890,"datasheet":"https:\/\/www.isocom.com\/wp-content\/uploads\/2021\/07\/DE93273.pdf","price":"$1.80 @ 1ku","product_introduction":"The IS281-4 from Isocom Components 2004 LTD is a 4-channel transistor output optocoupler in 16-pin PDIP through-hole package. Each channel consists of a GaAs infrared LED optically coupled to a silicon NPN phototransistor, providing 5000Vrms galvanic isolation. The 4-channel configuration simplifies multi-signal isolation in a single IC, and the through-hole PDIP package is ideal for prototyping and repairable assemblies. The CTR ranges from 50% to 300% at 5mA forward current, and the 80V BVCEO supports direct interface with 24V industrial logic. This is the through-hole version of the IS281-4GB (which is the SMD\/tape-and-reel variant).","working_principle":"The IS281-4 operates as a 4-channel optocoupler. (1) Each channel contains a GaAs infrared LED on the input side and a silicon NPN phototransistor on the output side, separated by an optically transparent insulation layer providing 5000Vrms galvanic isolation. When forward current flows through the LED, it emits infrared light detected by the phototransistor base, generating base current that turns on the transistor. (2) The CTR (Current Transfer Ratio) defines the relationship between LED forward current and phototransistor collector current. At IF=5mA, the CTR ranges from 50% to 300%, meaning the collector current can be 2.5mA to 15mA. The wide CTR range accounts for LED aging and temperature variation across the operating range. (3) The 0.6pF input-output capacitance provides excellent common-mode rejection, preventing high-frequency noise from coupling across the isolation barrier. The DC-to-300kHz bandwidth supports digital logic signals and low-frequency analog coupling.","pin_description":"
      Pin<\/th>Name<\/th>Function<\/th><\/tr>
      1<\/td>A1<\/td>Channel 1 LED anode<\/td><\/tr>
      2<\/td>C1<\/td>Channel 1 phototransistor collector<\/td><\/tr>
      3<\/td>E1<\/td>Channel 1 phototransistor emitter<\/td><\/tr>
      4<\/td>A2<\/td>Channel 2 LED anode<\/td><\/tr>
      5<\/td>C2<\/td>Channel 2 phototransistor collector<\/td><\/tr>
      6<\/td>E2<\/td>Channel 2 phototransistor emitter<\/td><\/tr>
      7<\/td>A3<\/td>Channel 3 LED anode<\/td><\/tr>
      8<\/td>C3<\/td>Channel 3 phototransistor collector<\/td><\/tr>
      9<\/td>E3<\/td>Channel 3 phototransistor emitter<\/td><\/tr>
      10<\/td>A4<\/td>Channel 4 LED anode<\/td><\/tr>
      11<\/td>C4<\/td>Channel 4 phototransistor collector<\/td><\/tr>
      12<\/td>E4<\/td>Channel 4 phototransistor emitter<\/td><\/tr>
      13,16<\/td>K1-K4<\/td>LED cathodes<\/td><\/tr><\/table>","application_scenarios":"
      • Industrial control signal isolation for PLC digital I\/O modules<\/li>
      • Power supply feedback loop isolation with 5000Vrms safety rating<\/li>
      • Medical equipment patient isolation for IEC 60601 compliance<\/li>
      • Communication interface ground loop elimination in RS-232\/485<\/li>
      • Multi-channel motor drive logic isolation with 4 channels per IC<\/li><\/ul>","alternative_models":"
        Model<\/th>Manufacturer<\/th>Key Difference<\/th><\/tr>
        IS281-4GB<\/td>Isocom<\/td>SMD \/ tape and reel version<\/td><\/tr>
        TLP281-4<\/td>Toshiba<\/td>4-channel, similar, SOIC-16<\/td><\/tr>
        PC847<\/td>Sharp<\/td>4-channel, DIP-16, similar<\/td><\/tr>
        CNY74-4H<\/td>Vishay<\/td>4-channel, DIP-16, similar<\/td><\/tr>
        LTV-847<\/td>Lite-On<\/td>4-channel, DIP-16, equivalent<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/7532","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=7532"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/7532\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/media?parent=7532"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/categories?post=7532"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/tags?post=7532"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=7532"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}