{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LM3S2939-EQC50-A2T","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"LM3S2939-EQC50-A2T","canonicalUrl":"https://icboms.com/texas-instruments/LM3S2939-EQC50-A2T","factsUrl":"https://icboms.com/api/mcp/products/LM3S2939-EQC50-A2T","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments Stellaris ARM Cortex-M3S 2000 32-bit MCU, LM3S2939-EQC50-A2T, 50MHz, 256KB Flash, 64KB RAM, 57 I/O, CANbus/SPI/I2C/UART, 100-LQFP, -40 to 105°C, 2.25-2.75V.","salesMarkdown":"## Stellaris Cortex-M3 with 50 MHz core and 256 KB Flash The LM3S2939-EQC50-A2T: The Flash holds the application firmware plus a bootloader; the 64 KB RAM leaves room for several CAN message buffers, a TCP/IP stack heap, and sensor data arrays without needing external SRAM on the board. ## Peripheral set for industrial connectivity The connectivity block includes CANbus, I²C, SPI, SSI, UART/USART, IrDA, Microwire, and a quadrature encoder interface (QEI). CANbus is the standout for industrial automation — it lets this MCU talk directly to motor drives, I/O blocks, and remote sensors over a two-wire differential bus without an external CAN controller. The QEI input decodes incremental encoder signals for closed-loop motor position feedback. Three 10-bit ADC channels handle basic analog sensing — thermistor temperature, potentiometer position, or current-shunt voltage. The 57 GPIOs map to the 100-LQFP package; about 40 remain after the serial peripherals and ADC are assigned, which is enough for a keypad matrix, status LEDs, and a few discrete control lines. On-chip brown-out detect and POR eliminate the external supervisor IC in many designs. The internal oscillator starts the core without a crystal, though the application note recommends an external 8-16 MHz crystal for CAN timing accuracy — the internal RC tolerance at 50 MHz is tight enough for UART but marginal for CAN bit timing at higher bus speeds. ## Industrial temperature grade and supply rail The -40°C to 105°C operating range qualifies this MCU for engine-bay electronics, outdoor telecom cabinets, and factory-floor controllers that see thermal cycling. The 2.25 V to 2.75 V supply rail means a single 2.5 V LDO powers the core and I/O — no separate 1.8 V rail needed for the Cortex-M3 logic. Texas Instruments has marked the LM3S2939-EQC50-A2T as Obsolete. The Stellaris family was migrated to the Tiva C series, but those parts use a different pinout and peripheral map — a board redesign is required to move to a Tiva or other current Cortex-M4 device. Available through independent distribution channels. No stock-holding claim — this is a per-order procurement line for BOM fills or last-time-buy extensions.","metaTitle":"Texas Instruments LM3S2939-EQC50-A2T ARM Cortex-M3, 50MHz","metaDescription":"Texas Instruments LM3S2939-EQC50-A2T 32-bit ARM Cortex-M3 MCU, 50MHz, 256KB Flash, 64KB RAM, 57 I/O, CANbus/SPI/I2C, 100-LQFP, -40 to 105°C.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["Microcontrollers & Processors (MCU / MPU / DSP)"],"specifications":{"Mfr":"Texas Instruments","Speed":"50MHz","Series":"Stellaris® ARM® Cortex®-M3S 2000","Package":"Tape & Reel (TR)","RAM Size":"64K x 8","Core Size":"32-Bit Single-Core","EEPROM Size":"-","Peripherals":"Brown-out Detect/Reset, POR, PWM, WDT","Connectivity":"CANbus, I²C, IrDA, Microwire, QEI, SPI, SSI, UART/USART","Mounting Type":"Surface Mount","Number of I/O":"57","Core Processor":"ARM® Cortex®-M3","Package / Case":"100-LQFP","Product Status":"Obsolete","Data Converters":"A/D 3x10b","Oscillator Type":"Internal","lifecycle_stage":"eol_hot","Base Product Number":"LM3S2939","Program Memory Size":"256KB (256K x 8)","Program Memory Type":"FLASH","Operating Temperature":"-40°C~105°C(TA)","Supplier Device Package":"100-LQFP (14x14)","Voltage - Supply (Vcc/Vdd)":"2.25V ~ 2.75V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/LM3S2939-EQC50-A2T/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy the LM3S2939-EQC50-A2T?","answer":"Sourced through independent distribution channels against an RFQ. Availability, pricing, and date codes are confirmed at quote time. Submit a request for the quantity you need."},{"question":"What is the closest pin-compatible alternative to the LM3S2939-EQC50-A2T?","answer":"The Tiva C series parts that succeeded Stellaris use a different pinout and peripheral map. A board redesign is required to migrate to a current Cortex-M4 MCU."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/LM3S2939-EQC50-A2T","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/LM3S2939-EQC50-A2T when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-21T02:51:48.352Z","lastPublished":"2026-07-21T02:51:48.352Z","indexable":true}}