{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LM3S5B91-IQC80-B1","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"LM3S5B91-IQC80-B1","canonicalUrl":"https://icboms.com/texas-instruments/LM3S5B91-IQC80-B1","factsUrl":"https://icboms.com/api/mcp/products/LM3S5B91-IQC80-B1","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments Stellaris® ARM® Cortex®-M3S 5000 microcontroller, LM3S5B91-IQC80-, 80MHz, 256KB Flash, 96KB RAM, 100-LQFP, -40°C to +85°C.","salesMarkdown":"## What this part is and what it brings to the board The LM3S5B91-IQC80-B1: It integrates 256 KB of flash and 96 KB of SRAM on-chip — the flash holds the application image and bootloader, while the SRAM gives the stack and heap enough room for real-time control loops without external memory. The 100-pin LQFP package (14x14 mm body) exposes 72 general-purpose I/O lines. The peripheral set includes a 16-channel 10-bit ADC, multiple serial interfaces (CAN, I²C, SPI, UART, USB OTG), and motion-control blocks like PWM and QEI — a fit for industrial drives, sensor hubs, or human-machine interface panels that need a single-chip control core. ## Memory and peripheral headroom for the firmware engineer 256 KB of on-chip flash (256K x 8) leaves room for a moderate application stack plus a RTOS kernel. The 96 KB SRAM (96K x 8) is split across the core and peripheral DMA — enough for double-buffered frame data in a display application or for holding a large parameter table without paging. The connectivity block covers CANbus, USB OTG, and multiple UART/USART channels — the CAN interface suits industrial automation backbones, while USB OTG lets the MCU act as either host or device for field-upgrade or data-logging roles. On-chip peripherals include a brown-out detect, POR, DMA, I²S audio interface, PWM, and a watchdog timer. The internal oscillator means the part can run without an external crystal for basic clocking, though the USB block will require an accurate external source for full-speed operation. ## Lifecycle reality and sourcing path Sourcing for this MCU goes through independent distribution and surplus channels. Each unit's date-code and marking are verified against TI's factory records before shipment — the laser etch and package traceability are checked for consistency. The 100-LQFP (14x14 mm) footprint is a standard JEDEC outline — replacement parts in the same package family exist, but a pin-compatible drop-in is not guaranteed without reviewing the full pinout and peripheral map.","metaTitle":"TI LM3S5B91-IQC80-B1 ARM Cortex-M3 MCU, 80MHz, 256KB Flash","metaDescription":"Texas Instruments LM3S5B91-IQC80-B1 Stellaris ARM Cortex-M3 MCU, 80MHz, 256KB Flash, 96KB RAM, 100-LQFP.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["Microcontrollers & Processors (MCU / MPU / DSP)"],"specifications":{"Mfr":"Texas Instruments","Speed":"80MHz","Series":"Stellaris® ARM® Cortex®-M3S 5000","Package":"Tray","RAM Size":"96K x 8","Core Size":"32-Bit Single-Core","EEPROM Size":"-","Peripherals":"Brown-out Detect/Reset, DMA, I²S, POR, PWM, WDT","Connectivity":"CANbus, EBI/EMI, I²C, IrDA, LINbus, Microwire, QEI, SPI, SSI, UART/USART, USB OTG","Mounting Type":"Surface Mount","Number of I/O":"72","Core Processor":"ARM® Cortex®-M3","Package / Case":"100-LQFP","Product Status":"Obsolete","Data Converters":"A/D 16x10b","Oscillator Type":"Internal","lifecycle_stage":"eol_hot","Base Product Number":"LM3S5B91","Program Memory Size":"256KB (256K x 8)","Program Memory Type":"FLASH","Operating Temperature":"-40°C~85°C(TA)","Supplier Device Package":"100-LQFP (14x14)","Voltage - Supply (Vcc/Vdd)":"1.08V ~ 1.32V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/68a166a6b00a801f61d8cbd87ba1cf20.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/LM3S5B91-IQC80-B1/alternatives.json"},"ai":{"faq":[{"question":"What is the LM3S5B91-IQC80-'s core speed and memory configuration?","answer":"The ARM Cortex-M3 core runs at 80 MHz. On-chip memory is 256 KB of flash and 96 KB of SRAM. The flash stores the application; the SRAM supports real-time data buffers and stack."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/LM3S5B91-IQC80-B1","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/LM3S5B91-IQC80-B1 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-21T02:55:06.609Z","lastPublished":"2026-07-21T02:55:06.609Z","indexable":true}}