NRND — what it means for the BOM line
Texas Instruments lists the LM3S2616-IQR50-A0T as NRND (Not Recommended for New Designs). That means this exact order code is still available for existing production builds, but TI will not support it in a new board spin — no guarantee of long-term supply or future PCN coverage. For a repair bench or a production line that already has this MCU in the BOM, the NRND status is a flag to review the next spin.
50 MHz Cortex-M3 with 128 KB flash
The core is an ARM Cortex-M3 running at 50 MHz — enough throughput for a CAN-based motor controller, a multi-axis QEI position loop, or a UART-to-CAN gateway without a second MCU. The 128 KB of on-chip flash and 16 KB of SRAM give the firmware stack room for a RTOS kernel, the protocol stack, and the application state machine. The 2.25 V to 2.75 V supply rail is tighter than a typical 3.3 V MCU — the board needs a dedicated regulator, not a shared 3.3 V rail.
Peripheral set and package
On-chip peripherals include CANbus, I²C, IrDA, QEI (quadrature encoder interface), and multiple UART/USART channels — the QEI is the differentiator here, letting the MCU read an incremental encoder directly without an external counter IC. Brown-out detect, POR, watchdog timer, and PWM are also integrated, reducing the external supervisor and timer count. The six-channel 10-bit ADC covers analog inputs like potentiometers or current-sense resistors without an external converter.