{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"PCF8574PW","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"PCF8574PW","canonicalUrl":"https://icboms.com/texas-instruments/PCF8574PW","factsUrl":"https://icboms.com/api/mcp/products/PCF8574PW","rawCanonicalId":null},"summary":{"shortDescription":"NXP PCF8574PW, I2C I/O Expander, 8 I/O, 100 kHz, Push-Pull Output, Interrupt, 2.5V-6V, -40°C-85°C, 20-TSSOP.","salesMarkdown":"## What this I2C I/O expander brings to the board The NXP PCF8574PW is an 8-bit I2C I/O expander in a 20-TSSOP package, providing eight bidirectional I/O lines controlled via the I2C bus at up to 100 kHz. It features push-pull outputs, a power-on reset (POR) circuit, and an interrupt output that signals the host when input levels change, reducing the need for constant polling. Output current is rated 1 mA source and 25 mA sink per pin, enough to drive LEDs directly or interface with small relays through a transistor. The 2.5 V to 6 V supply range means the expander can sit on a 3.3 V microcontroller bus without a level shifter, or on a 5 V industrial rail. The 1 mA source / 25 mA sink per pin is asymmetric — typical for I2C expanders — so if you are driving a load that needs more than 1 mA high-side, plan for an external pull-up or a transistor. The sink capability is generous: a single pin can handle a standard LED with a current-limiting resistor, or a small-signal relay coil if you stay within the package total power limit. ## Interrupt output and push-pull drive The interrupt output (INT) is an open-drain line that pulls low when any input pin changes state. In firmware, you connect INT to a GPIO edge-triggered interrupt on the host MCU, eliminating the need to poll the expander at a fixed interval. The push-pull output type on the I/O pins means you do not need external pull-up resistors on the I/O lines themselves — the expander drives them high and low actively, saving two resistors per pin versus an open-drain design. ## 20-TSSOP footprint and assembly The 20-TSSOP body measures 4.40 mm wide with a 0.65 mm pin pitch — a compact surface-mount package that fits on dense PCBs. It is supplied in Tube, so for automated pick-and-place you will need to transfer to a feeder-compatible carrier or order tape-and-reel variants (check the PCF8574PWR suffix).","metaTitle":"PCF8574PW I2C I/O Expander, 8-Bit, 20-TSSOP, 2.5V-6V","metaDescription":"PCF8574PW I2C I/O expander with 8 push-pull I/O, interrupt output, 2.5V-6V supply, -40°C to 85°C, 20-TSSOP. Active, ROHS3.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Interface & Transceivers"],"specifications":{"Mfr":"Texas Instruments","Series":"-","Package":"Tube","Features":"POR","Interface":"I²C","Output Type":"Push-Pull","Mounting Type":"Surface Mount","Number of I/O":"8","Package / Case":"20-TSSOP (0.173\\\", 4.40mm Width)","Product Status":"Active","Clock Frequency":"100 kHz","lifecycle_stage":"eol_hot","Interrupt Output":"Yes","Voltage - Supply":"2.5V ~ 6V","Base Product Number":"PCF8574","Operating Temperature":"-40°C~85°C","Supplier Device Package":"20-TSSOP","Current - Output Source/Sink":"1mA, 25mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$2.3400","priceTiers":[{"qty":1,"price":"$2.34000","currency":"USD"},{"qty":10,"price":"$2.10400","currency":"USD"},{"qty":25,"price":"$1.98480","currency":"USD"},{"qty":100,"price":"$1.69110","currency":"USD"},{"qty":250,"price":"$1.58788","currency":"USD"},{"qty":500,"price":"$1.38940","currency":"USD"},{"qty":1000,"price":"$1.15121","currency":"USD"},{"qty":2500,"price":"$1.12350","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/436451875093ef53a6afca337f2de9b8.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/PCF8574PW/alternatives.json"},"ai":{"faq":[{"question":"Does PCF8574PW have an interrupt output?","answer":"Yes, it has an interrupt output (INT) that signals the host MCU when any input pin changes state, reducing polling overhead."},{"question":"Can PCF8574PW be used with 3.3V?","answer":"Yes, the 2.5 V to 6 V supply range includes 3.3 V, so it works directly on a 3.3 V I2C bus without level shifting."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/PCF8574PW","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/PCF8574PW 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}}