{"id":7245,"date":"2026-06-23T07:55:46","date_gmt":"2026-06-23T07:55:46","guid":{"rendered":"https:\/\/materialparts.com\/ua78m05idcyr\/"},"modified":"2026-06-23T07:55:46","modified_gmt":"2026-06-23T07:55:46","slug":"ua78m05idcyr","status":"publish","type":"post","link":"https:\/\/materialparts.com\/zh\/ua78m05idcyr\/","title":{"rendered":"UA78M05IDCYR"},"content":{"rendered":"

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

The UA78M05IDCYR from Texas Instruments is a 500mA, 5V fixed-output positive voltage regulator in a TO-252 (DPAK) package. As part of the classic 78M00 series, it provides reliable 5V regulation with internal thermal shutdown and short-circuit protection.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n
Output Voltage<\/td>\n5 V (+\/-4%)<\/td>\n<\/tr>\n
\u8f93\u51fa\u7535\u6d41<\/td>\n500 mA<\/td>\n<\/tr>\n
\u8f93\u5165\u7535\u538b<\/td>\n7 V to 25 V<\/td>\n<\/tr>\n
Dropout Voltage<\/td>\n2 V (typical at 500mA)<\/td>\n<\/tr>\n
Line Regulation<\/td>\n10 mV (typical)<\/td>\n<\/tr>\n
Load Regulation<\/td>\n20 mV (typical)<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n-40C to +125C<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • 5V fixed output at 500mA in surface-mount DPAK package<\/li>\n
  • Internal thermal shutdown protection at 150C typical<\/li>\n
  • Internal short-circuit current limiting for fault protection<\/li>\n
  • Output transistor safe area compensation for reliable operation<\/li>\n
  • No external components required for basic operation<\/li>\n
  • Classic 78M00 series design with decades of proven reliability<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • 5V logic power supply from 9V or 12V input<\/li>\n
    • Microcontroller and digital IC voltage regulation<\/li>\n
    • Industrial control board local 5V regulation<\/li>\n
    • Automotive accessory power supply with thermal protection<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The UA78M05IDCYR from Texas Instruments is a 500mA, 5V fixed-output positive voltage regulator in a TO-252 (DPAK) package. As part of the classic 78M00 series, it provides reliable 5V regulation with internal thermal shutdown and short-circuit protection. Key Specifications Output Voltage 5 V (+\/-4%) Output Current 500 mA Input Voltage 7 V to […]<\/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":[138],"class_list":["post-7245","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-low-dropout-regulators-ldo","chip_brand-ti"],"acf":{"brief_explanation":"500mA 5V LDO, DPAK, thermal shutdown, short-circuit protection, 78M00 series classic","date_code":"","package_case":"TO-252 \/ DPAK (6.50 x 5.50 x 2.30 mm, surface mount, exposed tab)","in_stock":3858,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/ua78m.pdf","price":"$0.35 @ 1ku","product_introduction":"The UA78M05IDCYR from Texas Instruments is a 500mA, 5V fixed-output positive linear voltage regulator in a TO-252 (DPAK) surface-mount package. The device is part of the legendary 78M00 series that has been the workhorse of 5V power regulation for decades. The 500mA output current rating covers the majority of medium-power 5V logic applications, from microcontroller boards to sensor modules. The 2V typical dropout voltage requires a minimum input of 7V to maintain 5V output regulation, making it ideal for 9V battery or 12V supply inputs. Internal protection features include thermal shutdown at approximately 150C junction temperature, which prevents damage from excessive power dissipation, and current limiting with output transistor safe-area compensation, which protects against short-circuit conditions. The device requires no external components for basic operation, although input and output capacitors are recommended for stability and transient response. The DPAK package provides a surface-mount alternative to the classic TO-220, with the exposed tab serving as both the electrical ground connection and the primary thermal path to the PCB copper.","working_principle":"The UA78M05IDCYR uses a series-pass regulator topology with feedback control. (1) Series Pass Element: An internal NPN power transistor is connected between the input and output. The transistor operates in its linear region, dropping the excess input voltage across itself. (2) Voltage Reference: A temperature-compensated bandgap reference generates a stable 5V reference voltage. (3) Error Amplifier: The error amplifier compares a fraction of the output voltage (from the internal resistor divider) with the internal reference. If the output voltage is too low, the error amplifier increases the base drive to the pass transistor, increasing the output voltage. If too high, the drive is reduced. (4) Thermal Shutdown: A temperature sensor monitors the junction temperature. If it exceeds approximately 150C, the pass transistor is turned off, preventing thermal runaway and damage. When the junction cools below the hysteresis threshold, the regulator resumes operation. (5) Current Limit: The current limit circuit senses the output current through a small series resistor. If the current exceeds the limit (typically 750mA), the base drive to the pass transistor is reduced, limiting the current to a safe level.","pin_description":"
      Pin<\/th>Name<\/th>Type<\/th>Function<\/th><\/tr>
      1<\/td>IN<\/td>Power<\/td>Input voltage (7-25V)<\/td><\/tr>
      2<\/td>GND<\/td>Ground<\/td>Ground (tab, thermal contact)<\/td><\/tr>
      3<\/td>OUT<\/td>Output<\/td>Regulated 5V output<\/td><\/tr><\/table>","application_scenarios":"
      • 5V logic power supply from 9V or 12V input at 500mA in DPAK<\/li>
      • Microcontroller and digital IC voltage regulation with thermal protection<\/li>
      • Industrial control board local 5V regulation with proven 78M00 reliability<\/li>
      • Automotive accessory power supply with short-circuit current limiting<\/li><\/ul>","alternative_models":"
        Manufacturer<\/th>Part Number<\/th>Package<\/th>Notes<\/th><\/tr>
        TI<\/td>UA78M05CKCS<\/td>TO-220<\/td>Through-hole version<\/td><\/tr>
        onsemi<\/td>MC78M05ABDTG<\/td>DPAK<\/td>Equivalent, onsemi brand<\/td><\/tr>
        ST<\/td>L78M05ABDT-TR<\/td>DPAK<\/td>Equivalent, ST brand<\/td><\/tr>
        TI<\/td>LM2940T-5.0<\/td>TO-220<\/td>1A, low dropout alternative<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/7245","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=7245"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/7245\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/media?parent=7245"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/categories?post=7245"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/tags?post=7245"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=7245"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}