The STMicroelectronics STM32F411CEY3TR is a 32-bit ARM Cortex-M4 single-core MCU from the STM32F4 series, clocked at 100 MHz with 512 KB of Flash and 128 KB of RAM. It brings USB OTG, 10×12-bit ADC channels, and 36 I/O lines into a 49-WLCSP package measuring 3×3.19 mm — a footprint that fits wearable and sensor-node PCBs where every square millimetre counts.
The 100 MHz core executes a single-cycle multiply-and-accumulate. The 512 KB Flash and 128 KB RAM support a FreeRTOS image with a double-buffered ADC buffer.
USB OTG — host or peripheral on the same pin
49-WLCSP — board area vs assembly yield
The 49-WLCSP (3×3.19 mm) is a wafer-level chip-scale package with no mould compound. It saves board area but demands a controlled solder-paste stencil and reflow profile.