Texas Instruments LM3S811-EQN50-C2

Overview

LM3S811-EQN50-C2 from Texas Instruments is a 32-bit ARM Cortex-M3 microcontroller with 64 KB flash, 256-byte EEPROM, and 8 KB SRAM, operating at up to 50 MHz. It integrates UART, I²C, SSI, ADC (8-channel, 10-bit), PWM, analog comparator, and GPIOs-designed for real-time industrial control, motor drive monitoring, and embedded sensor interface applications.

For engineers reviewing the LM3S811-EQN50-C2 datasheet, LM3S811-EQN50-C2 pinout, LM3S811-EQN50-C2 application, or LM3S811-EQN50-C2 equivalent, key selection criteria include its 50 MHz CPU clock, integrated 10-bit ADC with temperature sensor, single UART + dual SSI + I²C interfaces, and QFP-48 package compatibility with legacy Stellaris designs.

Technical Context

The LM3S811-EQN50-C2 implements the ARMv7-M architecture with Thumb-2 instruction set, NVIC supporting 32 interrupt lines, and SysTick timer. Its memory system includes tightly coupled flash with prefetch buffer and SRAM with bit-band aliasing for atomic peripheral register access.

Peripherals are organized into APB buses (APB0 for GPIO, UART, SSI, I²C; APB1 for ADC, PWM, timers). Clocking uses an internal precision oscillator (±1% over temp) plus PLL support for 50 MHz operation, with configurable power modes including sleep, deep-sleep, and hibernate.

Key Specifications

Pinout & Package

LM3S811-EQN50-C2 is housed in a 48-pin LQFP (Leadless Quad Flat Package) with exposed thermal pad, rated for industrial temperature range (–40°C to +85°C) and RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microcontroller applications.

Compared with LM3S811-EQN50-C2, TM4C123GH6PM offers higher compute throughput and USB capability but requires board layout changes; STM32F030F4P6 reduces BOM cost and size but sacrifices EEPROM, ADC resolution, and serial interface flexibility.

Availability

LM3S811-EQN50-C2 is available at Aetrix Electronics and suitable for industrial motor control, smart sensor nodes, human-machine interface panels, and legacy PLC retrofit projects requiring stable component supply and long-lifecycle support.

Supply support for LM3S811-EQN50-C2 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader delivering analog, embedded processing, and wireless technologies with focus on reliability, energy efficiency, and system integration.

The Stellaris LM3S series was designed as TI's first ARM-based microcontroller family targeting cost-sensitive, real-time industrial and automation applications with integrated analog and communication peripherals.

FAQ

What is the maximum operating frequency of the LM3S811-EQN50-C2?

The LM3S811-EQN50-C2 operates at a maximum CPU clock frequency of 50 MHz, achieved using its internal PLL with precision oscillator reference. This speed supports real-time execution of control algorithms and high-throughput peripheral handling without external clock sources. The LM3S811-EQN50-C2 maintains timing compliance across the full industrial temperature range (–40°C to +85°C).

Does the LM3S811-EQN50-C2 include built-in nonvolatile memory beyond flash?

Yes, the LM3S811-EQN50-C2 integrates 256 bytes of EEPROM memory mapped into the address space, enabling reliable storage of calibration data, device IDs, or configuration parameters that persist across power cycles. Unlike flash, this EEPROM supports byte-level erase/write operations without block erasure - a feature directly supported by StellarisWare driver libraries. The LM3S811-EQN50-C2 uses flash-based emulation for this function, ensuring endurance of ≥100,000 write cycles.

Can the LM3S811-EQN50-C2 support simultaneous UART and I²C communication?

Yes, the LM3S811-EQN50-C2 supports concurrent UART and I²C operation: it features one dedicated UART peripheral (UART0) and one I²C master/slave controller (I²C0), each with independent clock domains and interrupt vectors. Firmware can manage both interfaces simultaneously - for example, receiving commands via UART while reading sensor data over I²C. The LM3S811-EQN50-C2's NVIC prioritization ensures deterministic response to either peripheral's interrupts.

What development tools are officially supported for the LM3S811-EQN50-C2?

Texas Instruments officially supports the LM3S811-EQN50-C2 with Keil MDK-ARM, IAR Embedded Workbench, and TI's Code Composer Studio v5.x and earlier. StellarisWare Peripheral Driver Library and evaluation boards like the EK-LM3S811 provide tested BSPs and example projects. Debugging uses JTAG/SWD via LM3S811-EQN50-C2's dedicated TCK/TMS/TDO/TDI pins - no SWD-only mode is available, as the part predates ARM's SWD standard adoption.

Is the LM3S811-EQN50-C2 pin-compatible with other Stellaris LM3S devices?

The LM3S811-EQN50-C2 shares the same 48-pin LQFP package and core pinout (power, reset, JTAG, GPIO banks A–D) with LM3S811 variants such as LM3S811-IQN50-C2 and LM3S811-EQN50-A2, differing only in temperature grade and screening. However, it is not pin-compatible with larger LM3S devices (e.g., LM3S9B92) due to differing peripheral mappings and pin counts. The LM3S811-EQN50-C2 maintains consistent signal assignment across all EQN50 suffix parts.