The STM32F051C8T7 is an STMicroelectronics 32-bit MCU built around the ARM Cortex-M0 core, running at 48 MHz from internal oscillator or external clock. The 48-LQFP package (7x7 mm) is a common footprint for rework and inspection; the 39 I/O lines give you room for a parallel LCD or a handful of encoder inputs alongside the usual serial buses.
The supply range spans 2V to 3.6V, so a 3.3V rail is the obvious choice, but a 2.5V or 3.0V rail works too, and a pair of alkaline cells in series can run it down to the low end before the brown-out reset kicks in.
Peripheral set for mixed-signal control
On the analog side you get a 13-channel 12-bit ADC and a single 12-bit DAC — enough for current sensing on a three-phase motor plus one analog output for a setpoint or trim. That covers most industrial sensor and actuator links without an external transceiver for the short-range ones.