Cortex-M3 in a 48-VQFN — board-fit and thermal note
The LM3S102-EGZ20-C2T: The 48-VQFN (7×7 mm) exposed-pad package requires a thermal via array under the pad to keep the junction below 105°C at maximum load — the datasheet's recommended footprint is the starting point for the PCB layout. The internal oscillator eliminates the external crystal for most applications, saving two I/O pins.
18 general-purpose I/O lines multiplex with I²C, SPI, SSI, and UART/USART interfaces. The peripheral set is suited for sensor aggregation (I²C for temperature/humidity, SPI for ADCs) and low-speed actuator control via the on-chip PWM generator. Built-in brown-out detect and power-on reset eliminate the external supervisor IC in cost-sensitive designs. The watchdog timer provides a last-resort recovery path for unattended equipment.
Temperature grade and deployment context
The 105°C ceiling gives margin above the typical 85°C industrial grade.