{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LM4040CEM3X-5.0/NOPB","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"LM4040CEM3X-5.0-NOPB","canonicalUrl":"https://icboms.com/texas-instruments/LM4040CEM3X-5.0-NOPB","factsUrl":"https://icboms.com/api/mcp/products/LM4040CEM3X-5.0%2FNOPB","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments LM4040CEM3X-5.0/NOPB precision shunt voltage reference, fixed 5V output, ±0.5% tolerance, 80 µVrms noise, SOT-23-3 package, -40°C to +125°C.","salesMarkdown":"## Fixed 5V shunt reference for precision bias and ADC rails The Texas Instruments LM4040CEM3X-5.0/NOPB is a precision shunt voltage reference delivering a fixed 5V output with ±0.5% initial tolerance. The shunt topology means it behaves like a two-terminal Zener — no separate supply pin, just a cathode and anode — which simplifies the BOM for generating a stable bias rail from an existing higher-voltage supply. ## Noise floor and temperature drift — the precision story For a 12-bit ADC with a 5V reference, that noise contribution sits well below 1 LSB, so you can skip the external RC filter on the reference input. The temperature coefficient is 100 ppm/°C — a 5V reference drifts 0.5 mV per °C, which adds about 0.01% of full-scale error over a 100°C swing. That is tight enough for most industrial control loops and data acquisition front-ends. ## Shunt current budget and cathode current floor The LM4040CEM3X-5.0/NOPB can sink up to 15 mA of output current while maintaining regulation. The minimum cathode current for stable operation is 83 µA — below that the reference may drop out of regulation. In practice, size the series resistor from the supply rail to deliver between 100 µA and 15 mA through the device, accounting for the load current drawn by the downstream circuit. A 1 kΩ resistor from a 12V rail gives about 7 mA bias, leaving headroom for a 5 mA load. The part comes in a standard SOT-23-3 package (TO-236-3 / SC-59 compatible). The three-pin footprint is the same as a small-signal transistor — anode, cathode, and no-connect (NC). No thermal pad is needed; the shunt reference dissipates power as I_cathode × V_reverse, and the SOT-23-3 copper trace area on a typical 2-layer board handles the thermal load up to 125°C ambient.","metaTitle":"TI LM4040CEM3X-5.0/NOPB Shunt Voltage Reference, 5V ±0.5%","metaDescription":"Texas Instruments LM4040CEM3X-5.0/NOPB precision shunt reference, fixed 5V output, ±0.5% tolerance, SOT-23-3, -40°C to +125°C.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Analog & Data Acquisition"],"specifications":{"Mfr":"Texas Instruments","Series":"-","Package":"Tape & Reel (TR); Cut Tape (CT)","Tolerance":"±0.5%","Output Type":"Fixed","Mounting Type":"Surface Mount","Package / Case":"TO-236-3, SC-59, SOT-23-3","Product Status":"Active","Reference Type":"Shunt","Voltage - Input":"-","lifecycle_stage":"eol_hot","Current - Output":"15 mA","Current - Supply":"-","Current - Cathode":"83 µA","Base Product Number":"LM4040","Noise - 0.1Hz to 10Hz":"-","Noise - 10Hz to 10kHz":"80µVrms","Operating Temperature":"-40°C~125°C(TA)","Supplier Device Package":"SOT-23-3","Temperature Coefficient":"100ppm/°C","Voltage - Output (Min/Fixed)":"5V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.9300","priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/db47fc1a31c797b619d88478be755429.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/LM4040CEM3X-5.0%2FNOPB/alternatives.json"},"ai":{"faq":[{"question":"What is the tolerance of the LM4040CEM3X-5.0/NOPB?","answer":"The LM4040CEM3X-5.0/NOPB has a ±0.5% initial tolerance on the fixed 5V output."},{"question":"Does the LM4040CEM3X-5.0/NOPB come in tape and reel?","answer":"Yes, the LM4040CEM3X-5.0/NOPB is available in Tape & Reel (TR) for automated assembly, as well as Cut Tape (CT) for smaller quantities."},{"question":"What is the closest pin-compatible alternative to the LM4040CEM3X-5.0/NOPB in this family?","answer":"Texas Instruments offers the LM4040 series across multiple voltage options and tolerance grades. The LM4040CEM3-5.0 is the same fixed 5V reference in the same SOT-23-3 package with the same ±0.5% tolerance — the suffix difference (no 'X') indicates a different tape/reel packing option. Both are pin-compatible and functionally identical for the BOM."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/LM4040CEM3X-5.0-NOPB","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/LM4040CEM3X-5.0-NOPB when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T18:03:28.771Z","lastPublished":"2026-07-22T18:03:28.771Z","indexable":true}}