64 MHz Cortex-M0+ with 64 KB Flash — what it buys you
The base product number STM32G031 covers a range of Flash and pin-count variants, all on the same STM32G0 platform, which simplifies a future density upgrade if the firmware grows beyond 64 KB.
Package and thermal — the 5x5 mm UFQFN with exposed pad
Housed in a 32-UFQFN with an exposed pad (supplier package 32-UFQFPN, 5x5 mm), this part is a surface-mount device. The 30 I/O lines give enough GPIO for a keypad, a small display, and a few sensor interrupts without needing a port expander.
Peripherals and connectivity — what is on the bus
On the peripheral side, the STM32G031K8U7 includes a 12-bit ADC with 18 channels, a DMA controller, PWM timers, a watchdog, brown-out detect, and POR.