50 MHz Cortex-M3 with on-chip Ethernet MAC
The LM3S6950-IQC50-A2 is a Stellaris ARM Cortex-M3S 6000 series microcontroller from Texas Instruments, built around a 32-bit ARM Cortex-M3 core clocked at 50 MHz. The 256 KB on-chip Flash and 64 KB RAM give enough room for a real-time OS, TCP/IP stack, and application buffers without external memory. The integrated Ethernet MAC (part of the connectivity block) handles 10/100 Mbit frames directly, which means this MCU can serve as a field controller or gateway node on an industrial network without an external PHY — though the PHY interface is still needed at the board level.
Industrial temperature grade and supply simplicity
The 46 GPIOs in this package count are enough to drive a parallel character LCD, a keypad matrix, and a few status LEDs without external port expanders.
Peripheral set and connectivity mix
Beyond Ethernet, the serial interface suite includes I²C, SPI, SSI, UART/USART, IrDA, and Microwire — covering most sensor buses and actuator links common in industrial control. The Quadrature Encoder Interface (QEI) directly decodes incremental encoder signals for motor position feedback without external logic. On-chip brown-out detect, POR, PWM, and watchdog timer reduce the need for external supervisor ICs. The internal oscillator means a crystal is optional for applications that can tolerate the internal accuracy — saving a board component and a layout trace.
Active lifecycle — sourcing for production and MRO
The base product number LM3S6950 covers the family; the -IQC50-A2 suffix encodes the temperature grade, speed, and package variant. Store the reels in dry storage — the 100-LQFP is moisture-sensitive per JEDEC MSL level 3, so bake before reflow if the floor life is exceeded.