Texas Instruments has marked the LM3S1R21-IQC80-C3 as Obsolete.
80MHz Cortex-M3 with 256KB Flash and 48K RAM
On-chip memory includes 256KB of Flash (256K x 8) and 48K x 8 of SRAM. This memory profile suits control applications with moderate firmware footprints and real-time data buffering, such as industrial I/O nodes or motor-control bridges.
100-LQFP package and board-fit considerations
Housed in a 100-LQFP package with a 14x14 mm body, the LM3S1R21-IQC80-C3 uses a 0.50 mm pitch that demands a 4-layer PCB for reliable fan-out of the inner rows.
The device provides 67 general-purpose I/O lines and a rich peripheral set including EBI/EMI, I²C, IrDA, LINbus, Microwire, SPI, SSI, and UART/USART interfaces. On-chip analog conversion comes from an 8-channel 10-bit ADC. Additional integrated blocks include brown-out detect/reset, DMA, POR, PWM, and a watchdog timer, which together reduce external component count in a control board.
Supply voltage range and power rail design
The core and I/O operate from a supply range of 1.08V to 3.6V. This wide Vcc/Vdd window allows the MCU to be powered from a 3.3V rail common in industrial control systems, or from a lower-voltage rail to reduce dynamic power in battery-backed applications.