{"id":7533,"date":"2026-06-25T07:58:13","date_gmt":"2026-06-25T07:58:13","guid":{"rendered":"https:\/\/materialparts.com\/lm78l12\/"},"modified":"2026-06-25T07:58:13","modified_gmt":"2026-06-25T07:58:13","slug":"lm78l12","status":"publish","type":"post","link":"https:\/\/materialparts.com\/zh\/lm78l12\/","title":{"rendered":"LM78L12"},"content":{"rendered":"

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

The LM78L12 is a classic three-terminal positive voltage regulator providing a fixed 12V output at up to 100mA from a higher unregulated DC input. Available in TO-92, SOIC-8, and other packages from multiple manufacturers.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Output Voltage<\/td>\n12 V (+\/-4% or +\/-2%)<\/td>\n<\/tr>\n
\u8f93\u51fa\u7535\u6d41<\/td>\n100 mA max<\/td>\n<\/tr>\n
\u8f93\u5165\u7535\u538b\u8303\u56f4<\/td>\n14.5V to 35V (for regulation)<\/td>\n<\/tr>\n
Dropout Voltage<\/td>\n2V typical<\/td>\n<\/tr>\n
Line Regulation<\/td>\n150 mV typical<\/td>\n<\/tr>\n
Load Regulation<\/td>\n150 mV typical<\/td>\n<\/tr>\n
\u9759\u6001\u7535\u6d41<\/td>\n3.8 mA typical<\/td>\n<\/tr>\n
Ripple Rejection<\/td>\n40 dB typical<\/td>\n<\/tr>\n
Thermal Shutdown<\/td>\nYes<\/td>\n<\/tr>\n
Short Circuit Protection<\/td>\nYes<\/td>\n<\/tr>\n
\u5305\u88c5<\/td>\nTO-92-3, SOIC-8, DSBGA<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n0 to +125 C (commercial)<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • Simple 3-terminal design requires only 2 external capacitors<\/li>\n
  • Internal thermal shutdown and short-circuit current limiting<\/li>\n
  • Available from multiple manufacturers (TI, ST, onsemi, etc.)<\/li>\n
  • TO-92 through-hole package for easy prototyping<\/li>\n
  • 40dB ripple rejection for adequate noise filtering<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • 12V bias supply for op-amps and comparators<\/li>\n
    • Relay and solenoid driver power supply<\/li>\n
    • Reference voltage generation<\/li>\n
    • Off-line auxiliary supply for small systems<\/li>\n
    • PCB local regulation for noise-sensitive circuits<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The LM78L12 is a classic three-terminal positive voltage regulator providing a fixed 12V output at up to 100mA from a higher unregulated DC input. Available in TO-92, SOIC-8, and other packages from multiple manufacturers. Key Specifications Output Voltage 12 V (+\/-4% or +\/-2%) Output Current 100 mA max Input Voltage Range 14.5V 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-7533","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-low-dropout-regulators-ldo","chip_brand-ti"],"acf":{"brief_explanation":"12V 100mA 3-terminal regulator, TO-92\/SOIC-8","date_code":"","package_case":"TO-92-3 (4.5 x 4.0 x 4.9 mm) \/ SOIC-8","in_stock":9876,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/lm78l.pdf","price":"$0.30 @ 1ku","product_introduction":"The LM78L12 is a widely available three-terminal positive voltage regulator that provides a fixed 12V output at up to 100mA load current. As a member of the LM78Lxx family, it requires only two external capacitors for operation and features internal thermal shutdown and short-circuit current limiting for self-protection. The device operates from an input voltage of 14.5V to 35V and provides +\/-4% output voltage accuracy over the commercial temperature range. Available in TO-92, SOIC-8, and DSBGA packages from multiple manufacturers including TI, STMicroelectronics, and onsemi, making it one of the most ubiquitous voltage regulators in the electronics industry.","working_principle":"The LM78L12 operates as a series linear voltage regulator. (1) A bandgap voltage reference generates a stable 1.25V reference voltage, which is amplified by an internal resistor divider to set the 12V output. The error amplifier compares a fraction of the output voltage (via the internal divider) with the reference, and adjusts the series pass transistor to maintain regulation. (2) The series pass element is a Darlington NPN transistor that drops the excess voltage (VIN - VOUT) across itself. The 2V typical dropout voltage means the minimum input voltage for regulation is 14V. At 100mA load, the pass transistor dissipates (VIN - 12V) x 0.1A as heat. (3) The thermal shutdown circuit monitors the die temperature and disables the output when junction temperature exceeds approximately 150C, protecting the device from damage. The short-circuit current limiter restricts the output current to approximately 200mA during fault conditions, preventing excessive power dissipation.","pin_description":"
      Pin (TO-92)<\/th>Name<\/th>Function<\/th><\/tr>
      1<\/td>OUT<\/td>12V regulated output<\/td><\/tr>
      2<\/td>GND<\/td>Common ground<\/td><\/tr>
      3<\/td>IN<\/td>Unregulated input (14.5-35V)<\/td><\/tr><\/table>","application_scenarios":"
      • 12V bias supply for op-amps, comparators, and analog circuits<\/li>
      • Relay and solenoid driver power supply with 100mA capability<\/li>
      • Reference voltage generation for ADC\/DAC circuits<\/li>
      • Off-line auxiliary supply for small microcontroller systems<\/li>
      • PCB local regulation to isolate noise-sensitive analog circuits from digital supply<\/li><\/ul>","alternative_models":"
        Model<\/th>Manufacturer<\/th>Key Difference<\/th><\/tr>
        LM78L05<\/td>TI\/ST\/onsemi<\/td>5V output, same family<\/td><\/tr>
        LM78L15<\/td>TI\/ST\/onsemi<\/td>15V output, same family<\/td><\/tr>
        LM2931AZ-12<\/td>TI<\/td>12V, LDO, 100mA, TO-92<\/td><\/tr>
        AMS1117-12<\/td>Advanced<\/td>12V, 1A, LDO, SOT-223<\/td><\/tr>
        KA78L12<\/td>KEC\/Fairchild<\/td>12V, 100mA, TO-92, equivalent<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/7533","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=7533"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/7533\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/media?parent=7533"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/categories?post=7533"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/tags?post=7533"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=7533"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}