50MHz ARM Cortex-M3 with 256KB Flash — where it fits
The LM3S1969-IQC50-A2: That memory profile suits control-loop firmware with moderate data logging — the flash holds the application image plus a small file system, while the SRAM leaves headroom for the stack and a real-time OS footprint. The 100-LQFP package (14x14 mm) is a hand-solderable fine-pitch QFP — rework is feasible with a hot-air station and a stencil, though the 0.5 mm pitch demands careful alignment.
Fifty-two GPIOs are available, though some share pins with the integrated peripherals: two UART/USART modules, two SPI/SSI ports, I²C, IrDA, a QEI for quadrature encoder inputs, and a Microwire interface. The 8-channel 10-bit ADC samples at the rated speed — enough for reading potentiometers, current-sense resistors, or thermistor dividers in a motor-drive feedback loop. The internal oscillator starts the core without a crystal — useful for a board that must boot before the external clock is stable.
Obsolete — sourcing reality and what replaces it
Texas Instruments has marked the LM3S1969-IQC50-A2 as obsolete. The Stellaris family was migrated to the Tiva C series, but those parts use a different package and peripheral map — a board respin is required for a drop-in replacement. Available through independent surplus and franchised-excess channels. Lot traceability and date codes are confirmed at RFQ. Pricing reflects the spot market for an end-of-life part — quote against your BOM quantity for current availability.