What this Stellaris Cortex-M3 brings to a 50 MHz control design
The LM3S628-IGZ50-C2: For connectivity it provides I²C, SPI, SSI, Microwire, and UART/USART interfaces, plus an 8-channel 10-bit ADC. The peripheral set suits sensor aggregation, motor-control feedback loops, and serial-communication bridging in industrial and embedded control applications.
50 MHz core speed and memory sizing for the BOM
The Cortex-M3 core runs at 50 MHz. The 28 I/O lines in a 48-VFQFN Exposed Pad package give decent pin density for the footprint. The exposed thermal pad on the 48-VQFN (7x7 mm) helps pull heat out of the package when the MCU is running continuous ADC conversions and PWM outputs at speed.
Peripheral set and simultaneous interface use
The part supports I²C and SPI simultaneously — these are separate peripheral modules on the Stellaris architecture, not a shared multiplexed block. The part also includes SSI (synchronous serial interface) and Microwire, plus UART/USART for asynchronous serial.