{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"BCR166W","brand":"Infineon Technologies","brandSlug":"infineon","productSlug":"BCR166W","canonicalUrl":"https://icboms.com/infineon/BCR166W","factsUrl":"https://icboms.com/api/mcp/products/BCR166W","rawCanonicalId":null},"summary":{"shortDescription":"Infineon BCR166W PNP pre-biased transistor, SC-70/SOT-323 package, 50 V Vce, 100 mA Ic, 250 mW, 160 MHz transition frequency, built-in 4.7 kOhm base and 47 kOhm emitter-base resistors.","salesMarkdown":"## Built-in resistors shrink the BOM The BCR166W integrates a 4.7 kOhm resistor in the base leg and a 47 kOhm resistor from emitter to base, so the transistor turns on and off with a single GPIO line — no external biasing network needed. That saves two passives per channel and cuts placement cost on high-count boards. ## Saturation voltage keeps losses low Vce(sat) maxes at 300 mV with 500 µA base drive and 10 mA collector current. For a 5 V logic rail switching a relay coil or LED string, that conduction drop is low enough to skip a heatsink in most ambient conditions. ## Package and footprint fit Board area is minimal — roughly 2.0 x 2.1 mm — so it fits dense layouts in portable or space-constrained designs. Listed as active on the Infineon product status.","metaTitle":"BCR166W PNP Pre-Biased Transistor, 160 MHz, SC-70/SOT-323","metaDescription":"BCR166W PNP pre-biased transistor in SC-70/SOT-323, 50 V, 100 mA, 250 mW, 160 MHz. Active lifecycle.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Discrete Semiconductors"],"specifications":{"Mfr":"Infineon Technologies","Series":"-","Package":"Bulk","Power - Max":"250 mW","Mounting Type":"Surface Mount","Package / Case":"SC-70, SOT-323","Product Status":"Active","Transistor Type":"PNP - Pre-Biased","lifecycle_stage":"eol_hot","Resistor - Base (R1)":"4.7 kOhms","Frequency - Transition":"160 MHz","Supplier Device Package":"PG-SOT323-3-1","Resistor - Emitter Base (R2)":"47 kOhms","Vce Saturation (Max) @ Ib, Ic":"300mV @ 500µA, 10mA","Current - Collector (Ic) (Max)":"100 mA","Current - Collector Cutoff (Max)":"100nA (ICBO)","DC Current Gain (hFE) (Min) @ Ic, Vce":"70 @ 5mA, 5V","Voltage - Collector Emitter Breakdown (Max)":"50 V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/ca565200a229b60fc4827216e2689e26.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the BCR166W used for?","answer":"As a PNP pre-biased transistor with built-in resistors, it is commonly used as a simple digital switch or driver — turning loads on/off from a microcontroller GPIO without external bias components. Typical applications include relay drivers, LED drivers, and interface circuits in consumer, industrial, and automotive electronics."},{"question":"What is the closest pin-compatible alternative to BCR166W in this component family?","answer":"Infineon offers several pre-biased PNP transistors in the same SOT-323 package with different resistor ratios. The BCR166W uses a 4.7 kOhm base resistor and 47 kOhm emitter-base resistor. Parts with the same package but different bias values (e.g., BCR135W with 10 kOhm / 47 kOhm) are not direct drop-in replacements because the on/off threshold changes with the resistor divider."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/infineon/BCR166W","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/infineon/BCR166W when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-17T19:50:00.618Z","lastPublished":"2026-07-17T19:50:00.618Z","indexable":true}}