The STM32L431CCU6TR: ARM Cortex-M4 core runs at 80 MHz with DSP and FPU extensions.
Memory and connectivity — sizing the firmware and the bus
256 KB of Flash is the mid-density option in the STM32L431 line; it holds a full RTOS, a TCP/IP stack, and application code for a sensor hub or a motor-control node without external memory. The 64 KB SRAM leaves room for double-buffered ADC data or a display frame buffer. On the peripheral side, the part brings CAN, QSPI, SAI, and SWPMI alongside the usual I²C, SPI, and UART — the QSPI interface lets you attach a serial NOR Flash for firmware-over-the-air staging, and the SAI provides an I²S audio bus for voice or sound playback.
Package and footprint — what the 48-UFQFPN means for the board
The 48-UFQFPN (7x7 mm) with exposed pad is a compact, low-inductance package.