81-WLCSP ARM Cortex-M4 with 1.5 MB Flash — what this package means for the board
It comes in an 81-ball WLCSP (4.04 x 3.95 mm) — a fine-pitch wafer-level chip-scale package that saves board area but demands controlled PCB design rules and reflow profile.
100 MHz Cortex-M4 with DSP and FPU — throughput for signal-chain work
The ARM Cortex-M4 core includes a single-precision FPU and DSP instructions, so the 100 MHz clock actually delivers cycle-efficient FFT, filter, and control-loop math. The 1.5 MB Flash is large enough to hold a full application stack plus an OTA update staging area; the 320 KB SRAM supports moderate frame buffers or multiple communication channels without external memory.
Connectivity and analog peripherals — CAN, USB OTG, dual 12-bit DAC
The 60 I/O count in the WLCSP package is respectable for a compact design — enough for a display, keypad, and sensor bus.
STMicroelectronics lists the STM32F413MHY6TR as Active.