What the 84 MHz Cortex-M4 buys you
The STM32F401RET6TR is an STM32F4-series 32-bit ARM Cortex-M4 MCU running at 84 MHz. That core includes a single-cycle multiply and a hardware FPU — so it handles PID loops, FFTs, or sensor fusion without a separate DSP.
I/O and connectivity for a control board
Fifty GPIOs in a 64-LQFP package leave room for a parallel LCD interface, a keypad matrix, and a handful of sensors. The 16-channel 12-bit ADC covers analog inputs like thermistors or current shunts without an external converter.
ST lists this part as Active.
It is not qualified for under-hood automotive (125°C) or avionics extended-temperature ranges — if your design needs that, look at the STM32F4 automotive-grade variants or the STM32G4 series with AEC-Q100 certification.
Supply range and power management
The built-in brown-out detect and POR eliminate the need for an external supervisor in many designs.