{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LQH43NN122K03L","brand":"Murata Electronics","brandSlug":"murata-electronics","productSlug":"LQH43NN122K03L","canonicalUrl":"https://icboms.com/murata-electronics/LQH43NN122K03L","factsUrl":"https://icboms.com/api/mcp/products/LQH43NN122K03L","rawCanonicalId":null},"summary":{"shortDescription":"Murata Electronics LQH43 series drum core wirewound inductor, 1.2 mH, 45 mA, 30 Ohm DCR, unshielded, 1812 (4532 Metric) surface mount.","salesMarkdown":"## 1.2 mH at 45 mA — the DC bias ceiling The LQH43NN122K03L is a drum core wirewound inductor from Murata's LQH43 series, rated 1.2 mH at 45 mA. That 45 mA is the DC current at which the inductance typically drops by 10% — push beyond it and the ferrite core saturates, collapsing the inductance and turning the part into a resistor. For a 1.2 mH choke in a low-current filter or DC-DC output stage, the 30 Ohm max DCR means the I²R loss at 45 mA is about 60 mW — negligible in most circuits, but the voltage drop across the winding at that current is 1.35 V, so the downstream rail sees that much less headroom. ## Self-resonant frequency and Q factor The self-resonant frequency (SRF) is 1.8 MHz. Above that frequency the inductor behaves capacitively — the inter-winding capacitance dominates. For a filter or resonant circuit, keep the operating frequency at least a decade below 1.8 MHz to stay in the inductive region. The Q factor is 40 at 252 kHz, which is moderate for a wirewound ferrite core; it tells you the ratio of reactance to resistance at that test frequency, so the component's AC loss is about 2.5% of the stored energy per cycle at 252 kHz. ## 1812 footprint, unshielded — layout considerations It is unshielded, so the magnetic field radiates into the surrounding PCB area — keep sensitive traces or other magnetics at least one package width away to avoid coupling.","metaTitle":"Murata LQH43NN122K03L Inductor, 1.2 mH, 45 mA, 1812","metaDescription":"Murata LQH43NN122K03L drum core wirewound inductor, 1.2 mH, 45 mA, 30 Ohm DCR, 1812 package, -40 to +105°C. Active production, sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Inductors & Chokes"],"specifications":{"Mfr":"Murata Electronics","Type":"Drum Core, Wirewound","Series":"LQH43","Package":"Tape & Reel (TR) Cut Tape (CT)","Ratings":"-","Q @ Freq":"40 @ 252kHz","Shielding":"Unshielded","Tolerance":"±10%","Inductance":"1.2 mH","Mounting Type":"Surface Mount","Package / Case":"1812 (4532 Metric)","Product Status":"Active","Material - Core":"Ferrite","lifecycle_stage":"unknown","Size / Dimension":"0.177\\\" L x 0.126\\\" W (4.50mm x 3.20mm)","Base Product Number":"LQH43NN","DC Resistance (DCR)":"30Ohm Max","Current Rating (Amps)":"45 mA","Height - Seated (Max)":"0.110\\\" (2.80mm)","Operating Temperature":"-40°C ~ 105°C","Supplier Device Package":"1812 (4532 Metric)","Frequency - Self Resonant":"1.8MHz","Current - Saturation (Isat)":"-","Inductance Frequency - Test":"1 kHz"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.2818","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/d0d6b1d39c76e30b3c05600906460c39.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the inductance tolerance and test condition?","answer":"The inductance is 1.2 mH with ±10% tolerance, tested at 1 kHz."},{"question":"What package does LQH43NN122K03L use?","answer":"It uses a standard 1812 (4532 Metric) surface-mount package, unshielded drum core wirewound construction."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/murata-electronics/LQH43NN122K03L","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/murata-electronics/LQH43NN122K03L when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:49:49.435Z","lastPublished":"2026-08-11T15:49:49.435Z","indexable":true}}