{"id":8016,"date":"2026-06-28T08:47:29","date_gmt":"2026-06-28T08:47:29","guid":{"rendered":"https:\/\/materialparts.com\/lm2576sx-adj-nopb-2\/"},"modified":"2026-06-28T11:43:50","modified_gmt":"2026-06-28T11:43:50","slug":"lm2576sx-adj-nopb-2","status":"publish","type":"post","link":"https:\/\/materialparts.com\/ar\/lm2576sx-adj-nopb-2\/","title":{"rendered":"LM2576SX-ADJ\/NOPB"},"content":{"rendered":"<h2>LM2576SX-ADJ\/NOPB Overview<\/h2>\n<p>The LM2576SX-ADJ\/NOPB is a SIMPLE SWITCHER series adjustable step-down DC-DC converter from Texas Instruments, with maximum input voltage of 40V, output current of 3A, in a TO-263-5 package. It integrates frequency compensation and a fixed frequency oscillator, greatly simplifying switching power supply design.<\/p>\n<h3>Key Features<\/h3>\n<ul>\n<li>Input voltage range: 4.5V-40V<\/li>\n<li>Adjustable output voltage: 1.23V-37V<\/li>\n<li>Maximum output current: 3A<\/li>\n<li>Switching frequency: 52kHz<\/li>\n<li>Standby current: 50uA (typical)<\/li>\n<li>Efficiency up to 88%<\/li>\n<li>Built-in thermal shutdown and current limiting<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>LM2576SX-ADJ\/NOPB Overview The LM2576SX-ADJ\/NOPB is a SIMPLE SWITCHER series adjustable step-down DC-DC converter from Texas Instruments, with maximum input voltage of 40V, output current of 3A, in a TO-263-5 package. It integrates frequency compensation and a fixed frequency oscillator, greatly simplifying switching power supply design. Key Features Input voltage range: 4.5V-40V Adjustable output voltage: 1.23V-37V [&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":[31,13],"tags":[],"chip_brand":[138],"class_list":["post-8016","post","type-post","status-publish","format-standard","hentry","category-dc-dc-converters","category-integrated-circuits-ics","chip_brand-ti"],"acf":{"brief_explanation":"3A step-down switching regulator, adjustable, TO-263-5","date_code":"","package_case":"TO-263-5 (10.0 x 8.7 x 4.6 mm)","in_stock":6696,"datasheet":"https:\/\/www.ti.com\/lit\/ds\/symlink\/lm2576.pdf","price":"$1.80 @ 1ku","product_introduction":"The LM2576SX-ADJ\/NOPB is a 3 A adjustable step-down switching voltage regulator from Texas Instruments in a TO-263-5 (D2PAK) surface-mount package, providing output voltage adjustable from 1.23 V to 37 V. Operating from a 4 V to 40 V input at a fixed 52 kHz switching frequency, it requires only four external components (inductor, Schottky diode, input capacitor, output capacitor) plus two feedback resistors. Features include 77 percent typical efficiency, TTL-compatible shutdown with 50 uA standby current, cycle-by-cycle current limiting, and thermal shutdown protection. The output voltage tolerance is plus or minus 4 percent over input line and output load conditions.","working_principle":"The LM2576SX-ADJ\/NOPB uses a fixed-frequency pulse-width modulation (PWM) buck converter topology operating at 52 kHz. The internal NPN Darlington power switch connects the input voltage to the output inductor during the on-time, causing inductor current to ramp up. When the switch turns off, the inductor current freewheels through the external Schottky catch diode, delivering stored energy to the output capacitor and load. The output voltage is sensed through an external resistor divider connected to the feedback (FB) pin, which is compared against the internal 1.23 V reference by the error amplifier. The error amplifier controls the PWM duty cycle to maintain the output at the desired voltage (Vout = 1.23 V x (1 + R2\/R1)). The cycle-by-cycle current limit monitors switch current and terminates the on-time if it exceeds approximately 4.5 A. The ON\/OFF pin allows TTL-level shutdown; pulling it below 1.4 V puts the device in standby mode with 50 uA typical current. Thermal shutdown disables the output switch when the die temperature exceeds approximately 170 C, with automatic recovery after cool-down. The 52 kHz switching frequency is a trade-off between inductor size and switching losses, allowing the use of low-cost standard inductors.","pin_description":"<table><tr><th>Pin<\/th><th>Name<\/th><th>Description<\/th><\/tr><tr><td>1<\/td><td>VIN<\/td><td>Input supply (4 V to 40 V); connect 100 uF electrolytic capacitor to GND<\/td><\/tr><tr><td>2<\/td><td>OUTPUT<\/td><td>Switch output; connect to inductor and Schottky catch diode cathode<\/td><\/tr><tr><td>3<\/td><td>GND<\/td><td>Ground; Tab is internally bonded to GND for thermal dissipation<\/td><\/tr><tr><td>4<\/td><td>FEEDBACK<\/td><td>Output voltage feedback; connect resistor divider from VOUT to set output (Vout = 1.23V x (1+R2\/R1))<\/td><\/tr><tr><td>5<\/td><td>ON\/OFF<\/td><td>Shutdown control; pull below 1.4 V to disable, leave open or pull above 2.4 V for normal operation<\/td><\/tr><tr><td>Tab<\/td><td>GND<\/td><td>Thermal tab; solder to PCB copper pour for heat dissipation<\/td><\/tr><\/table>","application_scenarios":"<ul><li><strong>Adjustable Power Supplies<\/strong>: Lab bench supplies and custom voltage rails from 1.23 V to 37 V with external resistor programming<\/li><li><strong>Automotive Down-Conversion<\/strong>: 12 V or 24 V battery to adjustable logic and analog supply rails<\/li><li><strong>Industrial 24 V to Variable Output<\/strong>: Programmable power for motor drivers, LED strings, and battery chargers<\/li><li><strong>Distributed Power Architecture<\/strong>: Intermediate bus conversion from 48 V or 24 V to point-of-load adjustable voltage<\/li><li><strong>Battery Charging<\/strong>: Adjustable constant-voltage charging stage for lead-acid and Li-ion battery packs<\/li><\/ul>","alternative_models":"<table><tr><th>Model<\/th><th>Manufacturer<\/th><th>Iout<\/th><th>Vin<\/th><th>Vout<\/th><th>Frequency<\/th><th>Package<\/th><\/tr><tr><td>LM2576S-ADJ\/NOPB<\/td><td>Texas Instruments<\/td><td>3 A<\/td><td>4-40 V<\/td><td>1.23-37 V<\/td><td>52 kHz<\/td><td>TO-263<\/td><\/tr><tr><td>LM2596S-ADJ\/NOPB<\/td><td>Texas Instruments<\/td><td>3 A<\/td><td>4-40 V<\/td><td>1.23-37 V<\/td><td>150 kHz<\/td><td>TO-263<\/td><\/tr><tr><td>LM2576HVSX-ADJ<\/td><td>Texas Instruments<\/td><td>3 A<\/td><td>4-60 V<\/td><td>1.23-57 V<\/td><td>52 kHz<\/td><td>TO-263<\/td><\/tr><tr><td>AP1509-K5G-13<\/td><td>BCD Semiconductor<\/td><td>2 A<\/td><td>4.5-40 V<\/td><td>1.23-37 V<\/td><td>150 kHz<\/td><td>SOIC-8<\/td><\/tr><tr><td>LMR33630<\/td><td>Texas Instruments<\/td><td>3 A<\/td><td>3.8-36 V<\/td><td>1.0-24 V<\/td><td>400 kHz<\/td><td>QFN\/HTSSOP<\/td><\/tr><\/table>\n<p>LM2576SX-ADJ\/NOPB is an adjustable 1.23-37V\/3A buck regulator from TI in TO-263-5. The LM2576S-ADJ provides the same in TO-263-5 with slightly different part numbering. The LM2596S-ADJ offers 150kHz switching for smaller inductors. The LMR51430 provides modern 500kHz switching in tiny VQFN. The AP1501A-K5G-13A offers lower-cost 3A adjustable in TO-263-5. The LM2676S-ADJ from TI provides 260kHz switching. For higher voltage, LM5005 provides 80V\/2.5A buck in HTSSOP-20.<\/p>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/8016","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/comments?post=8016"}],"version-history":[{"count":1,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/8016\/revisions"}],"predecessor-version":[{"id":8115,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/posts\/8016\/revisions\/8115"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/media?parent=8016"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/categories?post=8016"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/tags?post=8016"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/ar\/wp-json\/wp\/v2\/chip_brand?post=8016"}],"curies":[{"name":"\u062f\u0628\u0644\u064a\u0648 \u0628\u064a","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}