The STM32F401CCU6: The ARM Cortex-M4 core includes a single-precision FPU. Temperature range is industrial grade at -40°C to 85°C, suitable for outdoor telecom, factory sensors, and automotive cabin-adjacent modules.
USB OTG and peripheral set — what connects where
The USB OTG peripheral is a key differentiator in the 48-pin QFN package — it allows the MCU to act as either a USB host or device, which opens up direct connection to USB flash drives, keyboards, or a debug dongle without an external host controller. The 36 available I/O lines are enough for a small display, keypad, and a handful of sensors, but you will need to multiplex if the design calls for a parallel LCD or more than a few external peripherals. The I²S interface is useful for audio codec connection; the DMA engine can move data between peripherals and memory without CPU intervention, which matters when the core is busy with control loops.
Package and PCB layout — 48-UFQFN exposed pad
Housed in a 48-UFQFN exposed-pad package (supplier device package 48-UFQFPN, 7x7 mm), this is a surface-mount QFN with a central thermal pad.