Cortex-M3 at 50 MHz — on-chip memory and peripheral mix
The LM3S811-IQN50-C2T: On-chip peripherals include a brown-out detect, POR, watchdog timer, and PWM — the BOD and WDT eliminate external supervisor ICs in cost-sensitive control boards. Connectivity interfaces cover I²C, SPI, SSI, Microwire, and UART/USART — the SSI is a synchronous serial interface compatible with National Semiconductor Microwire peripherals, useful for legacy sensor bridges. A 4-channel 10-bit ADC is integrated on the die — for a 10-bit conversion at up to 1 Msps typical of this core, the ADC handles four analog inputs without an external multiplexer. The 32 I/O pins are available in the 48-LQFP package — 48 pins with 32 GPIO leaves 16 pins for power, ground, and dedicated function pins (oscillator, reset, JTAG/SWD).
NRND — sourcing path and design-in constraint
Texas Instruments has designated the LM3S811-IQN50-C2T as NRND (Not Recommended for New Designs) — the part is in its end-of-life transition phase, and TI no longer promotes it for new projects. For new designs, a pin-compatible or functionally equivalent alternative within the Stellaris or Tiva C series should be evaluated — the same 48-LQFP footprint and 3.3V supply rail are common across the family, but the exact peripheral set and memory map vary by derivative.