{"id":8029,"date":"2026-06-28T08:47:49","date_gmt":"2026-06-28T08:47:49","guid":{"rendered":"https:\/\/materialparts.com\/lm337imp-nopb-2\/"},"modified":"2026-06-28T11:43:39","modified_gmt":"2026-06-28T11:43:39","slug":"lm337imp-nopb-2","status":"publish","type":"post","link":"https:\/\/materialparts.com\/es\/lm337imp-nopb-2\/","title":{"rendered":"LM337IMP\/NOPB"},"content":{"rendered":"<h2>LM337IMP\/NOPB Overview<\/h2>\n<p>The LM337IMP\/NOPB is an adjustable negative voltage linear regulator from Texas Instruments with output range of -1.2V to -37V, maximum output current of 1.5A, in a SOT-223 package with 77dB ripple rejection, suitable for dual-rail power supply systems.<\/p>\n<h3>Key Features<\/h3>\n<ul>\n<li>Adjustable output: -1.2V to -37V<\/li>\n<li>Maximum output current: 1.5A<\/li>\n<li>Line regulation: 0.01%\/V<\/li>\n<li>Load regulation: 0.3%<\/li>\n<li>Ripple rejection: 77dB<\/li>\n<li>Built-in thermal shutdown and current limiting<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>LM337IMP\/NOPB Overview The LM337IMP\/NOPB is an adjustable negative voltage linear regulator from Texas Instruments with output range of -1.2V to -37V, maximum output current of 1.5A, in a SOT-223 package with 77dB ripple rejection, suitable for dual-rail power supply systems. Key Features Adjustable output: -1.2V to -37V Maximum output current: 1.5A Line regulation: 0.01%\/V Load [&hellip;]<\/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-8029","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-low-dropout-regulators-ldo","chip_brand-ti"],"acf":{"brief_explanation":"Negative adjustable LDO, -1.2 to -37V, 1A, SOT-223","date_code":"","package_case":"SOT-223 (6.50 x 3.50 x 1.60 mm)","in_stock":7997,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/lm337.pdf","price":"$0.95 @ 1ku","product_introduction":"The LM337IMP\/NOPB is a 1.5 A adjustable negative voltage regulator from Texas Instruments in a SOT-223 surface-mount package, providing output voltage from -1.2 V to -37 V. It complements the LM317 positive regulator for split-rail supply designs. Key features include 0.01 percent per volt line regulation, 0.3 percent load regulation, 77 dB ripple rejection, 1.5 A guaranteed output current, and internal current limiting with thermal shutdown. The device requires only two external resistors to set the output voltage and operates over a -40 C to +125 C junction temperature range.","working_principle":"The LM337IMP\/NOPB uses a floating regulator architecture where the output voltage is set by the ratio of two external resistors (R1 and R2) between the output, adjust, and ground nodes. The ADJ pin draws a small reference current (50 uA typical) that flows through R2, and the regulator maintains 1.25 V between the OUT and ADJ pins. The output voltage equals -1.25 V multiplied by (1 plus R2 divided by R1) minus the ADJ pin current multiplied by R2. An internal bandgap reference and error amplifier compare the output feedback with the reference voltage, driving a series pass transistor to maintain regulation. The current limit circuit protects the pass transistor by limiting output current to approximately 2.2 A under overload conditions. The thermal shutdown disables the output when junction temperature exceeds approximately 170 C, with automatic recovery after cool-down. The 77 dB ripple rejection at 120 Hz can be improved to over 80 dB by adding a 10 uF bypass capacitor from the ADJ pin to ground. A minimum load current of 10 mA must be maintained for proper regulation.","pin_description":"<table><tr><th>Pin<\/th><th>Name<\/th><th>Description<\/th><\/tr><tr><td>1<\/td><td>ADJ<\/td><td>Adjust pin; connect R1 to VOUT and R2 to GND to set output voltage<\/td><\/tr><tr><td>2<\/td><td>VOUT<\/td><td>Regulated negative output voltage; connect output capacitor (1 uF min) to GND<\/td><\/tr><tr><td>3<\/td><td>VIN<\/td><td>Input supply; must be more negative than VOUT by at least VDO (1.5 V typ at 1 A)<\/td><\/tr><tr><td>4<\/td><td>Tab\/VOUT<\/td><td>Thermal tab; electrically connected to VOUT, solder to copper pour for heatsinking<\/td><\/tr><\/table><p>Package: SOT-223-3 (DCY). Dimensions: 6.5 x 3.5 x 1.6 mm. Tab is internally bonded to VOUT and serves as the primary thermal dissipation path.<\/p>","application_scenarios":"<ul><li><strong>Split-Rail Power Supplies<\/strong>: Generating negative supply rails for op-amps and analog circuits from a single unregulated negative source<\/li><li><strong>LCD Bias Generation<\/strong>: Adjustable negative bias voltage for TFT LCD panel VGL and VCOM rails<\/li><li><strong>Audio Amplifier Rails<\/strong>: Symmetric positive\/negative supplies for class-AB and class-A headphone amplifiers<\/li><li><strong>Test Equipment<\/strong>: Variable negative supply for laboratory power supply and source-measure units<\/li><li><strong>Electrochemistry<\/strong>: Controlled negative potential for potentiostat circuits in electrochemical analysis<\/li><\/ul>","alternative_models":"<table><tr><th>Model<\/th><th>Manufacturer<\/th><th>Iout<\/th><th>Vout Range<\/th><th>Package<\/th><th>Notes<\/th><\/tr><tr><td>LM337T\/NOPB<\/td><td>Texas Instruments<\/td><td>1.5 A<\/td><td>-1.2 to -37 V<\/td><td>TO-220<\/td><td>Through-hole version<\/td><\/tr><tr><td>LM137H<\/td><td>Texas Instruments<\/td><td>1.5 A<\/td><td>-1.2 to -37 V<\/td><td>TO-39<\/td><td>Military temp range<\/td><\/tr><tr><td>LT3015<\/td><td>Analog Devices<\/td><td>1.5 A<\/td><td>-1.22 to -37 V<\/td><td>DDPAK-3<\/td><td>Lower noise, higher PSRR<\/td><\/tr><tr><td>LT1175<\/td><td>Analog Devices<\/td><td>500 mA<\/td><td>-1.22 to -30 V<\/td><td>SOIC-8<\/td><td>Lower current, SOIC package<\/td><\/tr><tr><td>NCP4624<\/td><td>onsemi<\/td><td>250 mA<\/td><td>-2.1 to -24 V<\/td><td>SOT-89<\/td><td>Lower current alternative<\/td><\/tr><\/table>\n<p>LM337IMP\/NOPB is a -1.25V to -37V adjustable negative regulator from TI in SOT-223. The LM337T provides the same in TO-220 for through-hole designs. The LM337MPX\/NOPB is the tape-and-reel version. The MC337 is the equivalent from onsemi with identical specifications. For lower current, the LM337LZ provides 100mA in TO-92. The LT1175 from ADI offers lower dropout negative regulation with 500mA in SOIC-8. The TPS7A3001 from TI provides -36V ultralow noise LDO alternative.<\/p>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/posts\/8029","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/comments?post=8029"}],"version-history":[{"count":1,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/posts\/8029\/revisions"}],"predecessor-version":[{"id":8102,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/posts\/8029\/revisions\/8102"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/media?parent=8029"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/categories?post=8029"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/tags?post=8029"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/es\/wp-json\/wp\/v2\/chip_brand?post=8029"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}