50 MHz Cortex-M3 with 128 KB flash — what the memory map means for your firmware
The LM3S1607-IQR50-A0T is a Stellaris-series ARM Cortex-M3 MCU from Texas Instruments, clocked at 50 MHz with a single 32-bit core. The 128 KB on-chip flash (128K x 8) and 32 KB SRAM (32K x 8) define the application ceiling — a bare-metal control loop with a moderate RTOS footprint typically leaves 60-70 KB of flash and 15-20 KB of RAM for the application stack after the HAL and scheduler.
NRND — sourcing reality for a part no longer recommended for new designs
Texas Instruments lists the LM3S1607-IQR50-A0T as NRND (Not Recommended for New Designs). This means the part is still available for existing production BOMs but is not qualified for new design starts — the factory will eventually issue an EOL notice with a last-time-buy window. For a production line that already carries this order code, the NRND status is a flag to evaluate a migration path.
Industrial temp grade and peripheral set — where it fits in a control board
The 2.25 V to 2.75 V supply rail means the MCU runs from a 2.5 V rail; the internal oscillator eliminates an external crystal for the core clock. The 8-channel 10-bit ADC samples analog feedback (thermistor, potentiometer, current-sense) without an external converter. On-chip peripherals include brown-out detect, POR, a watchdog timer, PWM outputs, and a DMA controller — the DMA offloads the Cortex-M3 core during high-rate data transfers (e.g., SPI to an external DAC or UART to a display), keeping the CPU free for the control loop.