{"id":6643,"date":"2026-06-18T15:53:51","date_gmt":"2026-06-18T15:53:51","guid":{"rendered":"https:\/\/materialparts.com\/lm7812ct\/"},"modified":"2026-06-18T15:53:51","modified_gmt":"2026-06-18T15:53:51","slug":"lm7812ct","status":"publish","type":"post","link":"https:\/\/materialparts.com\/zh\/lm7812ct\/","title":{"rendered":"LM7812CT"},"content":{"rendered":"

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

The LM7812CT from Texas Instruments is a fixed 12V positive voltage regulator delivering up to 1.5A. Part of the LM78xx series, it provides a stable 12V output from 14.5-35V input with internal thermal and short-circuit protection. Packaged in TO-220.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n\n\n
Output Voltage<\/td>\n12V (fixed)<\/td>\n<\/tr>\n
\u8f93\u51fa\u7535\u6d41<\/td>\n1.5A<\/td>\n<\/tr>\n
\u8f93\u5165\u7535\u538b<\/td>\n14.5V to 35V<\/td>\n<\/tr>\n
Dropout Voltage<\/td>\n2V (typ at 1A)<\/td>\n<\/tr>\n
Line Regulation<\/td>\n0.01%\/V (typ)<\/td>\n<\/tr>\n
Load Regulation<\/td>\n0.3%\/A (typ)<\/td>\n<\/tr>\n
Ripple Rejection<\/td>\n75dB (typ)<\/td>\n<\/tr>\n
\u5305\u88c5<\/td>\nTO-220<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n0 to +125 C<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • Fixed 12V output<\/li>\n
  • 1.5A output current<\/li>\n
  • Internal thermal overload protection<\/li>\n
  • Internal short-circuit current limiting<\/li>\n
  • 75dB ripple rejection<\/li>\n
  • No external components needed<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • 12V power supply for automotive electronics<\/li>\n
    • Relay and solenoid drive regulation<\/li>\n
    • Op-amp dual supply (+\/-12V with LM7912)<\/li>\n
    • Industrial 12V rail regulation<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The LM7812CT from Texas Instruments is a fixed 12V positive voltage regulator delivering up to 1.5A. Part of the LM78xx series, it provides a stable 12V output from 14.5-35V input with internal thermal and short-circuit protection. Packaged in TO-220. Key Specifications Output Voltage 12V (fixed) Output Current 1.5A Input Voltage 14.5V to 35V […]<\/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":[],"class_list":["post-6643","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-low-dropout-regulators-ldo"],"acf":{"brief_explanation":"Fixed 12V linear regulator, 1.5A, 14.5-35V input, TO-220","date_code":"","package_case":"TO-220","in_stock":2931,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/lm7800.pdf","price":"$0.40 @ 1ku","product_introduction":"The LM7812CT from Texas Instruments is a fixed 12V positive voltage regulator from the legendary LM78xx series. It provides a stable 12V output at up to 1.5A from an input voltage of 14.5V to 35V. The 2V dropout requires a minimum input of 14V for proper regulation. The 75dB ripple rejection cleans up noisy input supplies, particularly useful after rectifier bridges in AC-DC power supplies. Internal protection includes thermal shutdown at approximately 150C junction and current limiting at approximately 2.2A. The LM7812 is commonly used in automotive applications (regulating 12V from the car battery\/bus), relay driver power supplies, and as the positive rail of dual +\/-12V op-amp power supplies (paired with the LM7912CT). It is also used as a pre-regulator before lower-voltage LDO regulators.","working_principle":"The LM7812CT uses the same architecture as the LM7805CT: a series NPN pass transistor controlled by an error amplifier that compares a divided version of the output voltage to an internal bandgap reference. The internal resistor divider is set to produce 12V at the output. The NPN pass transistor requires a minimum dropout of approximately 2V (VBE + VCE(sat)). The thermal shutdown monitors die temperature and disables the output above approximately 150C. The current limiting circuit reduces drive when the pass transistor current exceeds approximately 2.2A. Safe-area compensation further reduces current limit as the input-output differential increases. Power dissipation must be managed with a heatsink: at 1A load with 18V input, dissipation is (18-12) x 1 = 6W.","pin_description":"
      Pin<\/th>Name<\/th>Function<\/th><\/tr>
      1<\/td>VIN<\/td>Unregulated input voltage (14.5-35V)<\/td><\/tr>
      2<\/td>GND<\/td>Ground \/ common<\/td><\/tr>
      3<\/td>VOUT<\/td>Regulated 12V output<\/td><\/tr><\/table>","application_scenarios":"
      • 12V automotive electronics power supply with 75dB ripple rejection<\/li>
      • Dual +\/-12V op-amp supply paired with LM7912CT negative regulator<\/li>
      • Relay and solenoid driver 12V rail from 18-24V industrial supply<\/li>
      • Pre-regulator providing stable 12V before lower-voltage LDO regulators<\/li><\/ul>","alternative_models":"
        Model<\/th>Manufacturer<\/th>Key Difference<\/th><\/tr>
        LM7805CT<\/td>TI<\/td>5V output version<\/td><\/tr>
        LM7808CT<\/td>TI<\/td>8V output version<\/td><\/tr>
        LM7912CT<\/td>TI<\/td>-12V complement for dual supplies<\/td><\/tr>
        LM317T<\/td>TI<\/td>Adjustable, can set 12V with resistors<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/6643","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=6643"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/6643\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/media?parent=6643"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/categories?post=6643"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/tags?post=6643"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=6643"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}